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icon1.gif  Engine @ ~100,000 miles, runs good but all original, what to do? [message #332564] Fri, 25 May 2018 18:51 Go to next message
GMC2000   United States
Messages: 193
Registered: March 2018
Location: Georgia
Karma: -3
Senior Member
most all the coaches Ive looked at are approaching 100,000 miles and the engine history is mostly unknown but lets say you get one with 100,000 on the clock that is running great and appears to be bone stock.

what service/maintenance, upgrades, and mods would you do to it right off the bat?

outside of the usual compression test, and from my reading up on these 455s so far:

-double roller Timing chain and sprockets
-remove intake manifold and install block off plates
-remove mechanical fuel pump and install block off plate and carter electric pump (or two)
-remove exhaust manifolds/headers and install remflex gaskets
-replace water pump with new roller bearing one and keep the old one as a known good spare for emergency useage
-replace oil cooler lines with new stainless braided lines
-upgrade to HEI ignition if existing one is mechanical
-replace starter with new and keep old one as a known good spare for emergency usage
-replace all belts, hoses, filters and keep old ones for spares

what else? is a knock sensor and indicator really a must have right away?

I havnt seen much stuff about any carb upgrades or mods except fuel injection and thats not something to do right away. how about adding an O2 sensor or two and a mixture indicator gauge?

or what other engine stuff do you think should be done A.S.A.P.?

oh yeah, lower radiator grille/guard if it hasnt one already. anything else to do before you take off for a +1000mi road trip?
Re: Engine @ ~100,000 miles, runs good but all original, what to do? [message #332565 is a reply to message #332564] Fri, 25 May 2018 19:18 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
Messages: 3005
Registered: August 2004
Location: Spanish Fort, AL
Karma: 9
Senior Member
If your exhaust manifolds are not leaking, do not remove just to install Remflex gaskets. Gasket set is cheap enough and consumes little storage room-just carry set as spare. Easy enough to change almost anywhere. Most time would be spent waiting for the engine to cool down. Generally, on the 455, it is the passenger side that lets go. Read back in the forum, on the cautions on replacing the Remflex.

When you install the intake block-off plate/gasket set (Dick Patterson set), replace the turkey tray with the smaller one from JmK.

Starter is generally easily available from auto parts store. I would not replace a know good one, until it fails. You should remove the cables to the starter and clean the crud off the cable ends and the starter studs. Apply anti-seize when reconnecting the cables. I replaced a good starter when all it needed was a clean ground path.

Replacing the hoses and fan belts is a good idea. Keeping the 'old' ones as spare might be a good idea, especially the belts. JR's oil cooler lines are an excellent replacement. Trash the old ones. You cannot break JR's oil lines. HEI yes.

It's your engine and your comfort zone.

Tom


2012 Phoenix Cruiser model 2552 KA4CSG

[Updated on: Fri, 25 May 2018 19:21]

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Re: Engine @ ~100,000 miles, runs good but all original, what to do? [message #332566 is a reply to message #332564] Fri, 25 May 2018 19:58 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
Senior Member
I would not remove mech pump
E pumps fail like clockwork.
Add a e pump via relay to Aux tank.


John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] Engine @ ~100, 000 miles, runs good but all original, what to do? [message #332569 is a reply to message #332565] Fri, 25 May 2018 20:12 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
Senior Member
Tom,

I'm going to disagree with you; there is no need to reinstall a turkey tray as the block off plates reduce the temperature in the
lifter valley to 173F.

http://www.gmcmhphotos.com/photos/aa-miscellaneous-photos/p63426-intake-manifold-internal-temp.html

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Thomas Phipps
Sent: Friday, May 25, 2018 7:19 PM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Engine @ ~100, 000 miles, runs good but all original, what to do?

If your exhaust manifolds are not leaking, do not remove just to install Remflex gaskets. Gasket set is cheap enough and consumes
little storage room-just carry set as spare. Easy enough to change almost anywhere. Most time would be spent waiting for the engine
to cool down. Generally, on the 455, it is the passenger side that lets go. Read back in the forum, on the cautions on replacing the
Remflex.

When you install the intake block-off plate/gasket set (Dick Patterson set), replace the turkey tray with the smaller one from JmK.

Starter is generally easily available from auto parts store. I would not replace a know good one, until it fails. You should remove
the cables to the starter and clean the crud off the cable ends and the starter studs. Apply anti-seize when reconnecting the
cables.

Replacing the hoses and fan belts is a good idea. Keeping the 'old' ones as spare might be a good idea, especially the belts. JR's
oil cooler lines are an excellent replacement. Trash the old ones. You cannot break JR's oil lines. HEI yes.

It's your engine and your comfort zone.

Tom
--
2012 Phoenix Cruiser model 2552
KA4CSG

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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: Engine @ ~100,000 miles, runs good but all original, what to do? [message #332574 is a reply to message #332564] Fri, 25 May 2018 20:48 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
Noname,

Changing to HEI is only a little of an upgrade. HEI is know for its low reliability. (Some may choose to argue, but GMs warranty does not.)
It is still has points, that is a maintenance issue that can be corrected without having to hammer the air filter housing into submission.

Replace the point set with a Pertronix 1181LS and never look back.
While you are at it, disassemble and lubricate the distributor.

Want more spark?
Get a real CDI. MSD is one of these just not my favorite as I have had two fail.

Other than that, do what you have to do to enjoy your coach.

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: [GMCnet] Engine @ ~100, 000 miles, runs good but all original, what to do? [message #332575 is a reply to message #332564] Fri, 25 May 2018 20:40 Go to previous messageGo to next message
Mike Kelley is currently offline  Mike Kelley   United States
Messages: 467
Registered: February 2017
Karma: -2
Senior Member
Fred:
Throw those old belts and hoses away after you have
acquired a good operational set and a 2nd (spare) set.
A spare set does not cost that much!
And - you don't want a worn/questionable set as your safety net.
Mike/The Corvair a holic

Sent from my iPhone

> On May 25, 2018, at 6:51 PM, Fred wrote:
>
> most all the coaches Ive looked at are approaching 100,000 miles and the engine history is mostly unknown but lets say you get one with 100,000 on the
> clock that is running great and appears to be bone stock.
>
> what service/maintenance, upgrades, and mods would you do to it right off the bat?
>
> outside of the usual compression test, and from my reading up on these 455s so far:
>
> -double roller Timing chain and sprockets
> -remove intake manifold and install block off plates
> -remove mechanical fuel pump and install block off plate and carter electric pump (or two)
> -remove exhaust manifolds/headers and install remflex gaskets
> -replace water pump with new roller bearing one and keep the old one as a known good spare for emergency useage
> -replace oil cooler lines with new stainless braided lines
> -upgrade to HEI ignition if existing one is mechanical
> -replace starter with new and keep old one as a known good spare for emergency usage
> -replace all belts, hoses, filters and keep old ones for spares
>
> what else? is a knock sensor and indicator really a must have right away?
>
> I havnt seen much stuff about any carb upgrades or mods except fuel injection and thats not something to do right away. how about adding an O2 sensor
> or two and a mixture indicator gauge?
>
> or what other engine stuff do you think should be done A.S.A.P.?
>
> oh yeah, lower radiator grille/guard if it hasnt one already. anything else to do before you take off for a +1000mi road trip?
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org

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Re: [GMCnet] Engine @ ~100, 000 miles, runs good but all original, what to do? [message #332579 is a reply to message #332575] Fri, 25 May 2018 20:53 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Just a comment about used water pumps as spares. When pumps are assembled,
they are lubricated with some consideration towards storage before they are
installed. After they have been used, the shaft and seal no longer have
that protection.
I have overhauled engines that took a long time to complete,
installed the old water pump and had them leak. Grrrrrrr. I put them in a
bucket of anti-freeze if I plan on using them over now, in hopes that the
seal won't dry out and leak.
I know, modern seals are not leather like old ones were and that might
change storage facts a bit.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Fri, May 25, 2018, 6:41 PM Mike Kelley wrote:

> Fred:
> Throw those old belts and hoses away after you have
> acquired a good operational set and a 2nd (spare) set.
> A spare set does not cost that much!
> And - you don't want a worn/questionable set as your safety net.
> Mike/The Corvair a holic
>
> Sent from my iPhone
>
>> On May 25, 2018, at 6:51 PM, Fred wrote:
>>
>> most all the coaches Ive looked at are approaching 100,000 miles and the
> engine history is mostly unknown but lets say you get one with 100,000 on
> the
>> clock that is running great and appears to be bone stock.
>>
>> what service/maintenance, upgrades, and mods would you do to it right
> off the bat?
>>
>> outside of the usual compression test, and from my reading up on these
> 455s so far:
>>
>> -double roller Timing chain and sprockets
>> -remove intake manifold and install block off plates
>> -remove mechanical fuel pump and install block off plate and carter
> electric pump (or two)
>> -remove exhaust manifolds/headers and install remflex gaskets
>> -replace water pump with new roller bearing one and keep the old one as
> a known good spare for emergency useage
>> -replace oil cooler lines with new stainless braided lines
>> -upgrade to HEI ignition if existing one is mechanical
>> -replace starter with new and keep old one as a known good spare for
> emergency usage
>> -replace all belts, hoses, filters and keep old ones for spares
>>
>> what else? is a knock sensor and indicator really a must have right away?
>>
>> I havnt seen much stuff about any carb upgrades or mods except fuel
> injection and thats not something to do right away. how about adding an O2
> sensor
>> or two and a mixture indicator gauge?
>>
>> or what other engine stuff do you think should be done A.S.A.P.?
>>
>> oh yeah, lower radiator grille/guard if it hasnt one already. anything
> else to do before you take off for a +1000mi road trip?
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> _______________________________________________
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>
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Re: [GMCnet] Engine @ ~100, 000 miles, runs good but all original, what to do? [message #332580 is a reply to message #332575] Fri, 25 May 2018 20:54 Go to previous messageGo to next message
Bruce Hart is currently offline  Bruce Hart   United States
Messages: 1501
Registered: October 2011
Location: La Grange, Wyoming
Karma: 5
Senior Member
If you have the original starter never give it up as a core. Have it
rebuilt by a professional.
It will last much longer than any remanufactured or new starters of today.

On Fri, May 25, 2018 at 7:40 PM, Mike Kelley wrote:

> Fred:
> Throw those old belts and hoses away after you have
> acquired a good operational set and a 2nd (spare) set.
> A spare set does not cost that much!
> And - you don't want a worn/questionable set as your safety net.
> Mike/The Corvair a holic
>
> Sent from my iPhone
>
>> On May 25, 2018, at 6:51 PM, Fred wrote:
>>
>> most all the coaches Ive looked at are approaching 100,000 miles and the
> engine history is mostly unknown but lets say you get one with 100,000 on
> the
>> clock that is running great and appears to be bone stock.
>>
>> what service/maintenance, upgrades, and mods would you do to it right
> off the bat?
>>
>> outside of the usual compression test, and from my reading up on these
> 455s so far:
>>
>> -double roller Timing chain and sprockets
>> -remove intake manifold and install block off plates
>> -remove mechanical fuel pump and install block off plate and carter
> electric pump (or two)
>> -remove exhaust manifolds/headers and install remflex gaskets
>> -replace water pump with new roller bearing one and keep the old one as
> a known good spare for emergency useage
>> -replace oil cooler lines with new stainless braided lines
>> -upgrade to HEI ignition if existing one is mechanical
>> -replace starter with new and keep old one as a known good spare for
> emergency usage
>> -replace all belts, hoses, filters and keep old ones for spares
>>
>> what else? is a knock sensor and indicator really a must have right away?
>>
>> I havnt seen much stuff about any carb upgrades or mods except fuel
> injection and thats not something to do right away. how about adding an O2
> sensor
>> or two and a mixture indicator gauge?
>>
>> or what other engine stuff do you think should be done A.S.A.P.?
>>
>> oh yeah, lower radiator grille/guard if it hasnt one already. anything
> else to do before you take off for a +1000mi road trip?
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>



--
Bruce Hart
1976 Palm Beach
Milliken, Co
GMC=Got More Class
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Bruce Hart 1976 Palm Beach 1977 28' Kingsley La Grange, Wyoming
Re: [GMCnet] Engine @ ~100, 000 miles, runs good but all original, what to do? [message #332581 is a reply to message #332580] Fri, 25 May 2018 21:20 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

I was advised to preemptively rebuild the engine and transmission on my coach when it hit 100,000 miles. I thought that was a dumb idea at the time, who does that? But when they both failed at 104,500 miles, I wished I had done just that. I got away with rebuilding without having to replace the block (I DID need a new crankshaft and rods), but had to spend money on things I wouldn't have had I taken that advice.

There are lots of exceptions, but the running gear of that era was generally good for not much more than 100,000 miles.

I totally agree with Jim H on the water pump. trying to reuse a used dried up water pump is asking for trouble. You WILL end up doing it again.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: Engine @ ~100,000 miles, runs good but all original, what to do? [message #332582 is a reply to message #332564] Fri, 25 May 2018 21:38 Go to previous messageGo to next message
George Beckman is currently offline  George Beckman   United States
Messages: 1085
Registered: October 2008
Location: Colfax, CA
Karma: 11
Senior Member
GMC2000 wrote on Fri, 25 May 2018 16:51
most all the coaches Ive looked at are approaching 100,000 miles and the engine history is mostly unknown but lets say you get one with 100,000 on the clock that is running great and appears to be bone stock.


Drive it. GM did a great job with their engines. Originals can go 140,000 and still use no oil. Rebuilds- Well, after 10K I would begin to trust it. Block off might not be a bad idea, but every time you open something, you can have trouble. Put a new fuel pump on if it is not fairly new as new gas can eat up the diaphragm. Just my take.


'74 Eleganza, SE, Howell + EBL
Best Wishes,
George
Re: Engine @ ~100,000 miles, runs good but all original, what to do? [message #332583 is a reply to message #332564] Fri, 25 May 2018 21:56 Go to previous messageGo to next message
Tom Lins is currently offline  Tom Lins   United States
Messages: 372
Registered: February 2004
Location: St Augustine, FL
Karma: 1
Senior Member
When we bought our first GMC we went by what someone said to us.
"Inspect and fix the things that will kill you first"
The tires, suspension, steering, bearings, and brakes
Then worry about the things that move you.
I would inspect all those things you mentioned and if anything is sketchy replace it and get rid of the old parts.
If you feel you need a spare buy a new one.
Change the oil and filter and when you get back send out a sample of the oil to be analyzed.

Then you will have an idea what you want to make improvements to.
There are a lot of GMCer's out there willing to lend a hand and advise, your not alone.
It is why we came back to our new GMC.

JMHO







Tom Lins
St Augustine, FL
77 GM Rear Twin, Dry Bath, 455, Aluminum Radiator Quad-Bag Suspension Solar Panel
Manuals on DVD
YOUTUBE Channel: GMC Dealer Training Tapes
http://www.bdub.net/tomlins/
Re: [GMCnet] Engine @ ~100, 000 miles, runs good but all original, what to do? [message #332584 is a reply to message #332582] Fri, 25 May 2018 21:49 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
In my experience, mechanical fuel pumps outlast electric ones, and they
perform consistently throughout their service life. They are susceptible to
alcohol deterioration, however, and when the diaphragm fails, they leak
fuel into the engine sometimes. Worth keeping a watchful eye on though.
They do stop pumping when the engine quits, which is a good thing.
Ask those who have had an underhood fire fed by an electric fuel
pump. Good idea to control them with a relay that opens when the engine
quits.
Jim Hupy

On Fri, May 25, 2018, 7:39 PM George Beckman wrote:

> GMC2000 wrote on Fri, 25 May 2018 16:51
>> most all the coaches Ive looked at are approaching 100,000 miles and the
> engine history is mostly unknown but lets say you get one with 100,000 on
>> the clock that is running great and appears to be bone stock.
>
>
> Drive it. GM did a great job with their engines. Originals can go 140,000
> and still use no oil. Rebuilds- Well, after 10K I would begin to trust it.
> Block off might not be a bad idea, but every time you open something, you
> can have trouble. Put a new fuel pump on if it is not fairly new as new gas
> can eat up the diaphragm. Just my take.
> --
> '74 Eleganza, SE, Howell + EBL
> Best Wishes,
> George
>
> _______________________________________________
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Re: Engine @ ~100,000 miles, runs good but all original, what to do? [message #332587 is a reply to message #332564] Fri, 25 May 2018 22:38 Go to previous messageGo to next message
GMC2000   United States
Messages: 193
Registered: March 2018
Location: Georgia
Karma: -3
Senior Member
I was thinking to replace the exhaust gaskets with known brand ones because that seems to be a very common issue and I'd rather do it at a convenient time and place.

the mechanical fuel pump on the Olds 455 has the same potential as many others (even europeans) to leak fuel into the crankcase. I'd rather have an electric one fail than that to happen even though its very rare. and it seems the e.pumps help eliminate vapor lock situations.

good point about the water pump drying out.. could try to seal it up in a bag with something in it but probably better just to get two new roller pumps and keep one as a back up.


I wouldnt want to do a preemptive rebuild unless something is glaringly not up to the task but I do plan to acquire another 455 at some point to build up from scratch and have on display on a stand and at the ready. someone here had mentioned a while back that a new block casting with improvements has recently become available, that might be worth looking more into someday.

I will definitely "drive it" but before I go too far off into the distance I want to cover all the well known bases but yes, GM engines can go a long time with proper service/maintenance.


Re: [GMCnet] Engine @ ~100, 000 miles, runs good but all original, what to do? [message #332589 is a reply to message #332584] Fri, 25 May 2018 22:45 Go to previous messageGo to next message
GMC2000   United States
Messages: 193
Registered: March 2018
Location: Georgia
Karma: -3
Senior Member
James Hupy wrote on Fri, 25 May 2018 21:49
In my experience, mechanical fuel pumps outlast electric ones, and they
perform consistently throughout their service life. They are susceptible to
alcohol deterioration, however, and when the diaphragm fails, they leak
fuel into the engine sometimes. Worth keeping a watchful eye on though.
They do stop pumping when the engine quits, which is a good thing.
Ask those who have had an underhood fire fed by an electric fuel
pump. Good idea to control them with a relay that opens when the engine
quits.
Jim Hupy



definitely will wire it up right. oil pres relay cut off and engine start position prime lead. another good point there though for sure. e.pumps can be deadly if wired the easy way.
Re: Engine @ ~100,000 miles, runs good but all original, what to do? [message #332593 is a reply to message #332564] Fri, 25 May 2018 23:48 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
Messages: 2126
Registered: July 2004
Location: Minden nevada
Karma: 6
Senior Member
If I purchased a coach that I believed had 100;000 miles on a 455 that was original I would be hesitant to make any long trips even with good oil pressure. For sure the factory timing chain and gears are very loose. My main concern would be the rod bearings . When I bought mine with a bad exhaust valve it had 95,000 on the motor ( in 1987). I kept thinking what if when I pulled the head with the bad valve. So I pulled the motor to ease my mind. Turned out it was a good decision as # 7 and 8 rod bearings were in bad shape and would have left me stranded at some point. In my opinion a 455 should be refreshed if it has 100,000 miles on it even if all you do is replace the bearings and timing gear set.

Roy Keen Minden,NV 76 X Glenbrook
Re: Engine @ ~100,000 miles, runs good but all original, what to do? [message #332595 is a reply to message #332564] Sat, 26 May 2018 09:02 Go to previous messageGo to next message
rjw   United States
Messages: 697
Registered: September 2005
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Senior Member
GMC2000 wrote on Fri, 25 May 2018 19:51
most all the coaches Ive looked at are approaching 100,000 miles and the engine history is mostly unknown but lets say you get one with 100,000 on the clock that is running great and appears to be bone stock.


I bought my GMC in 1998 when it had 119,577 on the odometer. The PO had changed the timing chain at ~80,000 miles. The extensive records I got at the time of the sale showed that not much else had been done to it other than routine maintenance. It had the original water pump. I drove it until 175,547 miles without incident other than replacing the exhaust manifold gaskets 3 times and starter. The first manifold repair was by Cinnabar (Remflex) that barely made it a year, next time by me, again with Remflex with about another year of service and then finally with Dave Lenzi's copper gaskets. Those gaskets have been flawless for going on ~80,000 miles with no leaks (on 2 motors). I have over 53,000 miles on my replacement engine with Dave's gaskets with no leaks.

I decided to replace the engine at 175,547 miles because it started to make a knocking/clicking noise. That noise ended up being caused by a collapsed lifter. It was probably a good thing I did it at that time because I found a leak in the intake manifold that was causing coolant to flow into the oil.

Because of the potential difficulty getting the exhaust manifold fasteners off, I would not want to attempt that sort of R&R on road.


Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com

Roller Cam 455, TBI+EBL, 3.42 FD, 4 Bag, Macerator, Lenzi (brakes, vacuum system, front end stuff), Manny Tranny, vacuum step, Tankless + OEM water heaters.
Re: Engine @ ~100,000 miles, runs good but all original, what to do? [message #332663 is a reply to message #332564] Sun, 27 May 2018 15:31 Go to previous messageGo to next message
GMC2000   United States
Messages: 193
Registered: March 2018
Location: Georgia
Karma: -3
Senior Member
good to know copper gaskets are available. Ive used them on other stuff with good results. I suppose that once you pull the intake off to install the block offs, you would be able to see how much baked oil is in there.

if its alot then surely some of it has broke off and circulated though into the bearings.

what about Mobil-1 oil? I wonder if using it would run the risk of breaking up that crud baked oil in there? might be better off not using it until after installing the block offs an cleaning some of that crap out as carefully as possible?
Re: [GMCnet] Engine @ ~100, 000 miles, runs good but all original, what to do? [message #332664 is a reply to message #332663] Sun, 27 May 2018 16:42 Go to previous messageGo to next message
johnd01 is currently offline  johnd01   United States
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Registered: July 2017
Location: Sacrameot
Karma: -1
Senior Member
Is there any truth to the rumor that Mobil-1 lubed engines leek more oil?

On Sun, May 27, 2018 at 1:31 PM, Fred wrote:

> good to know copper gaskets are available. Ive used them on other stuff
> with good results. I suppose that once you pull the intake off to install
> the
> block offs, you would be able to see how much baked oil is in there.
>
> if its alot then surely some of it has broke off and circulated though
> into the bearings.
>
> what about Mobil-1 oil? I wonder if using it would run the risk of
> breaking up that crud baked oil in there? might be better off not using it
> until
> after installing the block offs an cleaning some of that crap out as
> carefully as possible?
>
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Johnd01 John Phillips Avion A2600 TZE064V101164 Rancho Cordova, CA (Sacramento)
Re: [GMCnet] Engine @ ~100, 000 miles, runs good but all original, what to do? [message #332665 is a reply to message #332664] Sun, 27 May 2018 17:11 Go to previous messageGo to next message
GMC2000   United States
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johnd01 wrote on Sun, 27 May 2018 16:42
Is there any truth to the rumor that Mobil-1 lubed engines leek more oil?



not from my experience. Ive got an '88 truck I bought new and started using Mobil-1 in it after the first 500 miles and it has had nothing else since. it now has over 350,000 on it (SB V8) with no oil leaks and only minor seepage from the front of the oil pan but no drips from it.

I did have the cam seals start leaking in a FIAT Twin-Cam engine that I started using Mobil-1 in when I got it that were not leaking before then but I dont know if it was because the Mobil-1 is slicker or because I was reving it higher and longer than the previous owner but I have heard it will cause leaks to develop in older engines like the FIAT was that have actual rubber seals (real rubber) that has hardened over time.

but thanks for bringing that up, that is something to keep in mind since you cant take the oil pans off or replace rear seals easily in these. might not be worth it. Rotella would be my second choice.

I doubt Mobil-1 would turn into that baked sludge from the exhaust passage in the intake like others do though but that would be one of the first things I addressed.
Re: [GMCnet] Engine @ ~100, 000 miles, runs good but all original, what to do? [message #332666 is a reply to message #332664] Sun, 27 May 2018 17:17 Go to previous messageGo to previous message
Carl S. is currently offline  Carl S.   United States
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My personal opinion on exhaust manifold gaskets is that Dave Lenzi's copper gaskets are the best. I have used them on my coach and never had a failure. The only time I have had to replace them is when I have had to remove the manifolds for some reason. I have heard of Remflex failures from several other people and wondered why they keep using them. If you have headers, different story.

Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
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