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Re: [GMCnet] Transmission vacuum modulator leaking? [message #326961] Sat, 09 December 2017 23:27 Go to next message
jimk is currently offline  jimk   United States
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Registered: July 2006
Location: Belmont, CA
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Senior Member
There will be evidence there.

On Sat, Dec 9, 2017 at 9:24 PM, Jim Kanomata wrote:

> Just disconnect the Vac hose at the intake and see.
>
>
> On Sat, Dec 9, 2017 at 9:15 PM, Gordon Gibson
> wrote:
>
>> Hello all
>>
>> In the process of putting the coach to bed for winter, a new problem
>> seems to have surfaced. I am getting white smoke (sometimes a lot of it)
>> coming
>> out the tail pipe intermittently. First time I noticed it was after
>> stopping for lunch on a 200 mile drive. Starting back up I had white smoke
>> blowing for longer than I would expect from condensation. It stopped
>> fairly quickly and I did another 100 miles with no reoccurrence. Then
>> yesterday
>> I drove it to the gas station to fill the tanks up - just far enough so
>> that the temp gauge reached its normal operating level. White smoke on
>> starting up, and all the way home.
>>
>> Today I started the coach and had white smoke for the first 5 - 10
>> minutes, then it stopped. I checked fluid levels - coolant level seems
>> normal,
>> but ATF was a bit low. I added a half a quart then started up to measure
>> the level again....and the white smoke really came billowing out.
>>
>> My guess is a leaking diaphragm in the transmission vacuum modulator that
>> is allowing ATF to be sucked into the intake manifold. Does this sound
>> right? The tranny was rebuilt about 8,500 miles ago so the modulator
>> should have been replaced at that time. But the engine seems to be running
>> too
>> smoothly for it to be a cracked head or leaking head gasket. Besides,
>> the coolant level is holding steady. No coolant sludge on the engine oil
>> dipstick either.
>>
>> I know the right thing would be to lift the coach, pull the rubber hose
>> off the modulator and check to see if ATF drips out - but I just have dinky
>> car axle stands and am unwilling to crawl under the coach in my city
>> driveway just supported by the bottle jack. Building ramps is a project
>> for next
>> summer.
>>
>> So if this diagnosis sounds right to the group I will head to a tranny
>> shop Monday morning. Looks to me like the modulator should be very quick to
>> R&R. at a garage with a good floor jack and a pair of good axle stands.
>> They are forecasting 8 inches of snow for Tuesday so I'd really like to get
>> this fixed and the coach put away beforehand....
>> --
>> Gordon Gibson
>> 1976 23" Norris Upfit
>> Montreal West, Quebec, Canada
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
>



--
Jim Kanomata
Applied/GMC, Newark,CA
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1-800-752-7502
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Applied/GMC
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www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Transmission vacuum modulator leaking? [message #326965 is a reply to message #326961] Sun, 10 December 2017 05:18 Go to previous messageGo to next message
GMC.LES is currently offline  GMC.LES   United States
Messages: 505
Registered: April 2014
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Senior Member
If your engine was consuming enough coolant to make white smoke, you would likely detect a sweet odour to the exhaust.

I think you'll be lucky if a trans shop here in Montreal has a modulator in stock. No demand up here due to salt & rust taking out our vintage vehicles prematurely.

I would disconnect the vacuum line at the carb, and verify for presence of fluid. If the problem is related to the modulator, I'd be inclined to leave it disconnected and park the coach as is for the winter, making note that the modulator needs replacement. It will be much nicer to work on the coach in the warmer spring weather.

Les Burt
Montreal
'75 Eleganza 26'


> On Dec 10, 2017, at 12:27 AM, Jim Kanomata wrote:
>
> There will be evidence there.
>
>> On Sat, Dec 9, 2017 at 9:24 PM, Jim Kanomata wrote:
>>
>> Just disconnect the Vac hose at the intake and see.
>>
>>
>> On Sat, Dec 9, 2017 at 9:15 PM, Gordon Gibson
>> wrote:
>>
>>> Hello all
>>>
>>> In the process of putting the coach to bed for winter, a new problem
>>> seems to have surfaced. I am getting white smoke (sometimes a lot of it)
>>> coming
>>> out the tail pipe intermittently. First time I noticed it was after
>>> stopping for lunch on a 200 mile drive. Starting back up I had white smoke
>>> blowing for longer than I would expect from condensation. It stopped
>>> fairly quickly and I did another 100 miles with no reoccurrence. Then
>>> yesterday
>>> I drove it to the gas station to fill the tanks up - just far enough so
>>> that the temp gauge reached its normal operating level. White smoke on
>>> starting up, and all the way home.
>>>
>>> Today I started the coach and had white smoke for the first 5 - 10
>>> minutes, then it stopped. I checked fluid levels - coolant level seems
>>> normal,
>>> but ATF was a bit low. I added a half a quart then started up to measure
>>> the level again....and the white smoke really came billowing out.
>>>
>>> My guess is a leaking diaphragm in the transmission vacuum modulator that
>>> is allowing ATF to be sucked into the intake manifold. Does this sound
>>> right? The tranny was rebuilt about 8,500 miles ago so the modulator
>>> should have been replaced at that time. But the engine seems to be running
>>> too
>>> smoothly for it to be a cracked head or leaking head gasket. Besides,
>>> the coolant level is holding steady. No coolant sludge on the engine oil
>>> dipstick either.
>>>
>>> I know the right thing would be to lift the coach, pull the rubber hose
>>> off the modulator and check to see if ATF drips out - but I just have dinky
>>> car axle stands and am unwilling to crawl under the coach in my city
>>> driveway just supported by the bottle jack. Building ramps is a project
>>> for next
>>> summer.
>>>
>>> So if this diagnosis sounds right to the group I will head to a tranny
>>> shop Monday morning. Looks to me like the modulator should be very quick to
>>> R&R. at a garage with a good floor jack and a pair of good axle stands.
>>> They are forecasting 8 inches of snow for Tuesday so I'd really like to get
>>> this fixed and the coach put away beforehand....
>>> --
>>> Gordon Gibson
>>> 1976 23" Norris Upfit
>>> Montreal West, Quebec, Canada
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>>
>>
>>
>> --
>> Jim Kanomata
>> Applied/GMC, Newark,CA
>> jimk@appliedairfilters.com
>> http://www.appliedgmc.com
>> 1-800-752-7502
>>
>
>
>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

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Re: [GMCnet] Transmission vacuum modulator leaking? [message #326968 is a reply to message #326961] Sun, 10 December 2017 09:15 Go to previous messageGo to next message
gibsongo is currently offline  gibsongo   Canada
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Registered: October 2012
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Senior Member
Thanks for the answers guys. But one more question - If I disconnect the modulator vacuum line from the intake manifold, will the coach still be drivable? It's a fairly short distance to the storage place, but once there, the coach will be moved from time to time And if I do this, I assume that I should be capping the vacuum port on the manifold. Should I also be capping the line to the tranny vacuum modulator?

Gordon Gibson 1976 23" Norris Upfit Montreal West, Quebec, Canada
Re: [GMCnet] Transmission vacuum modulator leaking? [message #326971 is a reply to message #326968] Sun, 10 December 2017 10:15 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
es, drivable in first gear only. W

With vacuum removed the modulator thinks that you have your foot full throttle and it delays shifting to second until you reach some high RPM. Maybe 4500 or 5000 RPM. I have never tried it.

I fail to understand your hesitancy to fix the problem if it is indeed leaking. It is a simple one bolt removal to change it. You can slide under it and remove the bolt and hose. Then pull the modulator out. If you need more room drive up on something with the right front wheel only. I removed one in a parking lot in Nevada one time by simply driving up on a curb in a store parking lot.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Transmission vacuum modulator leaking? [message #326974 is a reply to message #326961] Sun, 10 December 2017 11:18 Go to previous messageGo to next message
gibsongo is currently offline  gibsongo   Canada
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Senior Member
Ken,
I get it, but...first I need to confirm the problem. Then I have to source a modulator. As Les Burt mentioned, that will probably involve getting it shipped from somewhere- most probably the US, which always takes twice as long as one would hope. Just this morning we got several inches of wet white fluffy stuff, and there's another 10 or so on the way on Tuesday. I've changed enough starters and water pumps lying under a car in the snow and slush to find procrastination an appealing course of action.

Also - I thought I read somewhere that the modulator needed to be adjusted by turning an internal set screw a given number of turns then fine tuning form smooth shifts. Is this the case?


Gordon Gibson 1976 23" Norris Upfit Montreal West, Quebec, Canada
Re: [GMCnet] Transmission vacuum modulator leaking? [message #326975 is a reply to message #326974] Sun, 10 December 2017 11:28 Go to previous messageGo to next message
bdub is currently offline  bdub   United States
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Registered: February 2004
Location: Central Texas
Karma: 5
Senior Member

Requires no adjustment.
http://www.buyautopartsonline.ca/catalog-1/itemdetail/acdelco-professional-c
anada/89057789

-----Original Message-----
From: Gmclist On Behalf Of Gordon Gibson
Sent: Sunday, December 10, 2017 11:18 AM

Ken,
I get it, but...first I need to confirm the problem. Then I have to source
a modulator. As Les Burt mentioned, that will probably involve getting it
shipped from somewhere- most probably the US, which always takes twice as
long as one would hope. Just this morning we got several inches of wet white
fluffy stuff, and there's another 10 or so on the way on Tuesday. I've
changed enough starters and water pumps lying under a car in the snow and
slush
to find procrastination an appealing course of action.

Also - I thought I read somewhere that the modulator needed to be adjusted
by turning an internal set screw a given number of turns then fine tuning
form smooth shifts. Is this the case


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bdub
'76 Palm Beach/Central Texas
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Re: [GMCnet] Transmission vacuum modulator leaking? [message #326976 is a reply to message #326975] Sun, 10 December 2017 11:45 Go to previous messageGo to next message
GMC.LES is currently offline  GMC.LES   United States
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Registered: April 2014
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Senior Member
Gordon,
Once you have determined if the modulator is at fault, I suggest you make a few calls first thing Monday morning to see if a local auto parts or trans shop can supply the modulator quickly. The answer to that quest will quickly help you decide whether to procrastinate.

Les Burt
Montreal
'75 Eleganza 26'


> On Dec 10, 2017, at 12:28 PM, Billy Massey wrote:
>
> Requires no adjustment.
> http://www.buyautopartsonline.ca/catalog-1/itemdetail/acdelco-professional-c
> anada/89057789
>
> -----Original Message-----
> From: Gmclist On Behalf Of Gordon Gibson
> Sent: Sunday, December 10, 2017 11:18 AM
>
> Ken,
> I get it, but...first I need to confirm the problem. Then I have to source
> a modulator. As Les Burt mentioned, that will probably involve getting it
> shipped from somewhere- most probably the US, which always takes twice as
> long as one would hope. Just this morning we got several inches of wet white
> fluffy stuff, and there's another 10 or so on the way on Tuesday. I've
> changed enough starters and water pumps lying under a car in the snow and
> slush
> to find procrastination an appealing course of action.
>
> Also - I thought I read somewhere that the modulator needed to be adjusted
> by turning an internal set screw a given number of turns then fine tuning
> form smooth shifts. Is this the case
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

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Re: [GMCnet] Transmission vacuum modulator leaking? [message #326982 is a reply to message #326974] Sun, 10 December 2017 15:55 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
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gibsongo wrote on Sun, 10 December 2017 11:18


Also - I thought I read somewhere that the modulator needed to be adjusted by turning an internal set screw a given number of turns then fine tuning form smooth shifts. Is this the case?


Check this for Vacuum modulator adjustment.

http://www.gmcmhphotos.com/photos/transmission-install/p26806-img-0716.html



Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: [GMCnet] Transmission vacuum modulator leaking? [message #327032 is a reply to message #326961] Mon, 11 December 2017 22:33 Go to previous messageGo to next message
gibsongo is currently offline  gibsongo   Canada
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Registered: October 2012
Location: Montreal West, Quebec, Ca...
Karma: 0
Senior Member
Thanks to all for your helpful comments.

But....(sigh)....looks like the diagnostic for an easy fix is incorrect. I pulled the modulator vacuum hose off the manifold and it was bone dry. Also, disconnecting it made no difference to the white smoke billowing out the exhaust pipe. The final "nail in the coffin" is probably that the low coolant warning light lit up after 15 minutes of idling.

So I guess I have to accept that Prestone is finding its way into the combustion chambers somehow. AAAARGH I guess there is no quick fix and that the problem is either a blown head gasket, or a crack in the block or a cylinder head.


Gordon Gibson 1976 23" Norris Upfit Montreal West, Quebec, Canada
Re: [GMCnet] Transmission vacuum modulator leaking? [message #327034 is a reply to message #327032] Mon, 11 December 2017 23:02 Go to previous messageGo to next message
GMC.LES is currently offline  GMC.LES   United States
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Registered: April 2014
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Senior Member
Gordon,

Since you are certain that it is consuming coolant, you will need to protect the engine from the possibility of coolant sitting in the cylinders and causing rust over the winter storage period.

If procrastination wins, at a minimum, you need to drain the rad and engine block of coolant, and preferably fog the engine to protect the cylinder walls.

Draining just the rad won't totally eliminate the risk of coolant migrating into the cylinders. You need to pull the block drains as well.

Les Burt
Montreal
'75 Eleganza 26'


> On Dec 11, 2017, at 11:33 PM, Gordon Gibson wrote:
>
> Thanks to all for your helpful comments.
>
> But....(sigh)....looks like the diagnostic for an easy fix is incorrect. I pulled the modulator vacuum hose off the manifold and it was bone dry.
> Also, disconnecting it made no difference to the white smoke billowing out the exhaust pipe. The final "nail in the coffin" is probably that the low
> coolant warning light lit up after 15 minutes of idling.
>
> So I guess I have to accept that Prestone is finding its way into the combustion chambers somehow. AAAARGH I guess there is no quick fix and that
> the problem is either a blown head gasket, or a crack in the block or a cylinder head.
> --
> Gordon Gibson
> 1976 23" Norris Upfit
> Montreal West, Quebec, Canada
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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Re: [GMCnet] Transmission vacuum modulator leaking? [message #327035 is a reply to message #327034] Mon, 11 December 2017 23:57 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Registered: January 2004
Location: Hebron, Indiana
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To reinforce the previous posting about antifreeze in the cylinders. I am working on one that has 2.9% antifreeze in the oil. The pistons rings were rusted to he cylinder walls. Looking at it with a borescope (camera) showed just slight traces of rust on the walls right next to the pistons. I removed all plugs and squirted PB Blaster all around the piston tops 3 times in 7 days. It did not help. So I mixed up some Acetone and PSF and filled all cylindesr to the bottom of the spark plug holes and let it soak. I tried several times a week to turn the engine and nothing. Finally after three weeks of soaking and applying air pressure to the cylinders that had valves closed, I got the engine freed up.

My point out of all of this is If there is any chance of getting anti-freeze (and water) in those cylinders, I would make a special effort to soak down the tops of those pistons as much as possible. You could also go through removing plugs and filling cylinders with something like ATF or very thin oil. That is your choice but if it is going to be parked for an extended period of time, put something in it. I do not know if just fogging it is enough.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Transmission vacuum modulator leaking? [message #327042 is a reply to message #326961] Tue, 12 December 2017 10:49 Go to previous messageGo to next message
gibsongo is currently offline  gibsongo   Canada
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Once again, thanks for the helpful comments guys. Given what I think to be the nature of the problem, procrastination has ceased to be an option and I am trying to find a a garage to fix it. My preference would be to bring it back to Borrmann's Garage in Bluevale ON (500 miles away) but that's probably not a wise idea.

My experience is that it's hard to find good garages to work on GMCs. The truck places don't like to work on motorhomes and their preferences go to diesel motors. Garages focused more on cars often don't have service bays big enough and they don't like tying their lifts up for days while searching for parts or having machine work done.


Gordon Gibson 1976 23" Norris Upfit Montreal West, Quebec, Canada
Re: [GMCnet] Transmission vacuum modulator leaking? [message #327043 is a reply to message #327042] Tue, 12 December 2017 11:09 Go to previous messageGo to next message
bdub is currently offline  bdub   United States
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Location: Central Texas
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Would it be advisable to insert some radiator stop leak and head out for
Boremanns at first light? Only slowing down for fuel and fluids.

bdub

On Tue, Dec 12, 2017 at 10:49 AM, Gordon Gibson
wrote:

> Once again, thanks for the helpful comments guys. Given what I think to
> be the nature of the problem, procrastination has ceased to be an option and
> I am trying to find a a garage to fix it. My preference would be to bring
> it back to Borrmann's Garage in Bluevale ON (500 miles away) but that's
> probably not a wise idea.
>
> My experience is that it's hard to find good garages to work on GMCs.
> The truck places don't like to work on motorhomes and their preferences go
> to
> diesel motors. Garages focused more on cars often don't have service bays
> big enough and they don't like tying their lifts up for days while
> searching for parts or having machine work done.
> --
> Gordon Gibson
> 1976 23" Norris Upfit
> Montreal West, Quebec, Canada
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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bdub
'76 Palm Beach/Central Texas
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Re: [GMCnet] Transmission vacuum modulator leaking? [message #327048 is a reply to message #327043] Tue, 12 December 2017 11:39 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Make sure your fluid has harly any Anti Freeze as that will cause the
bearings to lock up. ​

On Tue, Dec 12, 2017 at 9:09 AM, Billy Massey wrote:

> Would it be advisable to insert some radiator stop leak and head out for
> Boremanns at first light? Only slowing down for fuel and fluids.
>
> bdub
>
> On Tue, Dec 12, 2017 at 10:49 AM, Gordon Gibson gordon.gibson@videotron.ca>
> wrote:
>
>> Once again, thanks for the helpful comments guys. Given what I think to
>> be the nature of the problem, procrastination has ceased to be an option
> and
>> I am trying to find a a garage to fix it. My preference would be to
> bring
>> it back to Borrmann's Garage in Bluevale ON (500 miles away) but that's
>> probably not a wise idea.
>>
>> My experience is that it's hard to find good garages to work on GMCs.
>> The truck places don't like to work on motorhomes and their preferences
> go
>> to
>> diesel motors. Garages focused more on cars often don't have service
> bays
>> big enough and they don't like tying their lifts up for days while
>> searching for parts or having machine work done.
>> --
>> Gordon Gibson
>> 1976 23" Norris Upfit
>> Montreal West, Quebec, Canada
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
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> Unsubscribe or Change List Options:
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>



--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
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Question [message #327335 is a reply to message #327048] Wed, 20 December 2017 09:36 Go to previous messageGo to next message
gibsongo is currently offline  gibsongo   Canada
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Hello all,

Once again, thanks for the comments and suggestions. A couple of more questions if I may. I still haven't managed to locate a garage willing to work on my "white smoke problem". Several have indicated that they would be willing to take a look in January when their bread and butter business slows down a little.
Question 1: how long I have before facing serious rust resulting from what is probably a little anti freeze leaking into one or several combustion chambers. Are we talking months here....or weeks....or days? If it's days, I may already be too late.
Question 2: Should I be starting the engine regularly to keep things oiled, or does that worsen the problem since I may be drawing more antifreeze into the combustion chamber(s)?
Question 3: bdub suggested putting in some Bars Leaks and making a run to Bluevale. I'll admit this is a tempting option, but what are the chances of a can of this stuff actually temporarily stopping/slowing the lead enough to drive 500 + miles? And don't I run the risk of permanently gumming up the radiator, heater core and coolant passages in the engine block? i.e. Would this cure possibly be worse than the illness?

Frank from Borrmann's garage has suggested getting a radiator pressure tester kit, pressurizing the system, looking for a pressure drop then pulling spark plugs to see which cylinders are affected. It's supposed to warm up to just a few degrees below freezing on the weekend, so this is how I may be spending the day before Christmas....


Gordon Gibson 1976 23" Norris Upfit Montreal West, Quebec, Canada
Re: [GMCnet] Transmission vacuum modulator leaking? [message #327336 is a reply to message #326961] Wed, 20 December 2017 10:09 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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Senior Member
If you have coolant in the cylinder(s) you're likely looking at taking it apart anyhow. The sooner the better.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell
Re: [GMCnet] Question [message #327338 is a reply to message #327335] Wed, 20 December 2017 11:23 Go to previous messageGo to next message
Kingsley Coach is currently offline  Kingsley Coach   United States
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Gordon

I have a pressure tester you can borrow but there is a catch...I won't be
home until the middle of February. If you aren't in a rush, it's available
to you for shipping costs both ways but knowing Canada Post, that's not
really an attractive deal...

50 years ago I learned you can't find a mechanic in a can BUT I have no
experience with Bars. If the leak is limited to the cylinder (ie head
gasket) you may be all right, but if the antifreeze is in the oil, you will
soon have a boat anchor as the bearings will be toast.

Borrow a leak tester now or wait until I get back. Good luck

Mike currently in NM

On Wed, Dec 20, 2017 at 11:36 AM, Gordon Gibson
wrote:

> Hello all,
>
> Once again, thanks for the comments and suggestions. A couple of more
> questions if I may. I still haven't managed to locate a garage willing to
> work on my "white smoke problem". Several have indicated that they would
> be willing to take a look in January when their bread and butter business
> slows down a little.
> Question 1: how long I have before facing serious rust resulting from what
> is probably a little anti freeze leaking into one or several combustion
> chambers. Are we talking months here....or weeks....or days? If it's
> days, I may already be too late.
> Question 2: Should I be starting the engine regularly to keep things
> oiled, or does that worsen the problem since I may be drawing more
> antifreeze
> into the combustion chamber(s)?
> Question 3: bdub suggested putting in some Bars Leaks and making a run to
> Bluevale. I'll admit this is a tempting option, but what are the chances of
> a can of this stuff actually temporarily stopping/slowing the lead enough
> to drive 500 + miles? And don't I run the risk of permanently gumming up
> the radiator, heater core and coolant passages in the engine block? i.e.
> Would this cure possibly be worse than the illness?
>
> Frank from Borrmann's garage has suggested getting a radiator pressure
> tester kit, pressurizing the system, looking for a pressure drop then
> pulling
> spark plugs to see which cylinders are affected. It's supposed to warm up
> to just a few degrees below freezing on the weekend, so this is how I may
> be spending the day before Christmas....
> --
> Gordon Gibson
> 1976 23" Norris Upfit
> Montreal West, Quebec, Canada
>
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--
Michael Beaton
1977 Kingsley 26-11
1977 Eleganza II 26-3
Antigonish, NS

Life is too short to hold a grudge; slash some tires and call it even !
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Re: Question [message #327371 is a reply to message #327335] Wed, 20 December 2017 20:28 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
gibsongo wrote on Wed, 20 December 2017 10:36
Hello all,

Once again, thanks for the comments and suggestions. A couple of more questions if I may. I still haven't managed to locate a garage willing to work on my "white smoke problem". Several have indicated that they would be willing to take a look in January when their bread and butter business slows down a little.
Question 1: how long I have before facing serious rust resulting from what is probably a little anti freeze leaking into one or several combustion chambers. Are we talking months here....or weeks....or days? If it's days, I may already be too late.
Question 2: Should I be starting the engine regularly to keep things oiled, or does that worsen the problem since I may be drawing more antifreeze into the combustion chamber(s)?
Question 3: bdub suggested putting in some Bars Leaks and making a run to Bluevale. I'll admit this is a tempting option, but what are the chances of a can of this stuff actually temporarily stopping/slowing the lead enough to drive 500 + miles? And don't I run the risk of permanently gumming up the radiator, heater core and coolant passages in the engine block? i.e. Would this cure possibly be worse than the illness?

Frank from Borrmann's garage has suggested getting a radiator pressure tester kit, pressurizing the system, looking for a pressure drop then pulling spark plugs to see which cylinders are affected. It's supposed to warm up to just a few degrees below freezing on the weekend, so this is how I may be spending the day before Christmas....


Gordon,

I have been following your thread and hoping this would get closed, but I guess I have to jump in.....

If you are actually loosing coolant and can't see where and/or the engine is smoking more than you like, there is a even bet that you have an internal coolant leak. Mine was identified by the oil analysis and a doping of Bar's Leaks didn't fix it. So, my engine is coming out this winter.

There are three real good possibilities for such leaks.
A cylinder head gasket is a very common issue. More common in cold climates and even more if the engine is short cycled.
An intake gasket has coolant ports that can leak coolant into the lube oil. Said coolant will (mostly) come out of the lube oil when the engine gets to temperature. That vapor will get sucked into the intake system but the PCV system.
A third that I almost hate to bring up is a cracked cylinder head. Unfortunately, this is not a rare failure in the Olds 455.

What I would do if I were you and you are where it is cold (Quebec is even colder that Michigan) and the engine may not opened up for a while, is "Fog" the engine. Talk to some boat people. This is just an easy way to oil the bores and other bare metal internal parts to prevent corrosion. If you can't manage that, at least pull the plugs and squirt oil in to prevent damage.

And yes, as KenB said, changing out a modulator is simple, but do it when the transmission has just been shut down because it is at the running level of the fluid.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: Question [message #327454 is a reply to message #327371] Sun, 24 December 2017 12:31 Go to previous messageGo to next message
gibsongo is currently offline  gibsongo   Canada
Messages: 116
Registered: October 2012
Location: Montreal West, Quebec, Ca...
Karma: 0
Senior Member
Mike, thanks for the offer but I have to get this taken care of sooner rather than later. So far I haven't gotten any nasty notes through the door, but a visit from the local constabulary informing me of my violation of municipal regulations can't be too far off.... Matt - my guestimate diagnosis matches yours - I missed your string from this summer about the same subject but found it doing a search of this site on cylinder heads. What did you end up doing finally - engine out or just the heads? And what did you end up finding?

I've found a garage with big bays about 40 miles away that will accommodate me, and am booked in on January 3rd. I've got my fingers crossed hoping for a head gasket problem rather than a cracked head. Just in case I've been looking around for "J" heads, but haven't located any so far. Hopefully I won't need them.......

Merry Christmas to you all!


Gordon Gibson 1976 23" Norris Upfit Montreal West, Quebec, Canada
Re: Question [message #327464 is a reply to message #327454] Sun, 24 December 2017 18:56 Go to previous messageGo to previous message
Matt Colie is currently offline  Matt Colie   United States
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
gibsongo wrote on Sun, 24 December 2017 13:31
Mike, thanks for the offer but I have to get this taken care of sooner rather than later. So far I haven't gotten any nasty notes through the door, but a visit from the local constabulary informing me of my violation of municipal regulations can't be too far off.... Matt - my guestimate diagnosis matches yours - I missed your string from this summer about the same subject but found it doing a search of this site on cylinder heads. What did you end up doing finally - engine out or just the heads? And what did you end up finding?

I've found a garage with big bays about 40 miles away that will accommodate me, and am booked in on January 3rd. I've got my fingers crossed hoping for a head gasket problem rather than a cracked head. Just in case I've been looking around for "J" heads, but haven't located any so far. Hopefully I won't need them.......

Merry Christmas to you all!

Gordon,

I don't have mine open yet. There were other demands on my time and after talking to Dave Lenzi I decided to pull the front frame out the front. I have enough room to do that. I could have pulled it out the top. As with a 23, that is not so tough. But the refit of the front dress sounds a whole lot like a "ship in a bottle" that I don't have the patience for. I did manage to acquire access to both a pair of G and a pair of J heads. (They were still bolted to engines. Part of my hold up.) Both of which look good to a visual inspection. (My visual inspections are pretty good, but can't beat magnetic particle.) I am hoping to pull the frame out just after the new year.

Keep us posted..

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
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