Home » Public Forums » GMCnet » [GMCnet] reasons for using oil?
| [GMCnet] reasons for using oil? [message #64461] |
Mon, 16 November 2009 10:27  |
KB
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Registered: September 2009
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Is there a list somewhere of all the reasons our engine is using oil?
Things to check or usual problems that cause this symptom?
We changed the oil right after we bought it, drove it 500 miles from
San Diego to San Jose, and now the oil is *really* low. I'll change
it soon and see exactly how low, but it's not good.
thanks,
Karen
1973 23' Patience Tester
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1975 26'
San Jose, CA
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| Re: [GMCnet] reasons for using oil? [message #64478 is a reply to message #64461] |
Mon, 16 November 2009 12:01  |
fred v
Messages: 999
Registered: April 2006
Location: pensacola, fl.
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there was a very long thread on "oil consumption" just recently. i've been using a qt. every 250 miles on a fairly new engine. i changed valve stem seals, PCV valve, valve cover filter and made sure i wasn't adding too much oil.
the latest thinking is that you may not have motorhome valve covers. the auto ones have a different baffle inside and can cause the engine to suck oil. i'm about to replace mine and see if it makes a difference.
Fred V
'77 Royale RB 455
P'cola, Fl
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| Re: [GMCnet] reasons for using oil? [message #64483 is a reply to message #64461] |
Mon, 16 November 2009 12:24 |
Bob de Kruyff
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
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""We changed the oil right after we bought it, drove it 500 miles from
San Diego to San Jose, and now the oil is *really* low. I'll change
it soon and see exactly how low, but it's not good.""
Karen--what type and viscosity of oil are you using?
Bob de Kruyff
78 Eleganza
Chandler, AZ
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| Re: [GMCnet] reasons for using oil? [message #64495 is a reply to message #64478] |
Mon, 16 November 2009 13:38 |
roy1
Messages: 2126
Registered: July 2004
Location: Minden nevada
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If you think you are sucking oil out of the valve cover I would disconnect the pvc hose where it connects to the carburetor and see if it is dry or dripping oil . If it is dry your problem is elsewhere.
Roy
Roy Keen
Minden,NV
76 X Glenbrook
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| Re: [GMCnet] reasons for using oil? [message #64524 is a reply to message #64461] |
Mon, 16 November 2009 16:13 |
Rick Denney
Messages: 430
Registered: January 2004
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KB writes...
> Is there a list somewhere of all the reasons our engine is using oil?
> Things to check or usual problems that cause this symptom?
> We changed the oil right after we bought it, drove it 500 miles from
> San Diego to San Jose, and now the oil is *really* low. I'll change
> it soon and see exactly how low, but it's not good.
There are several possible causes for oil consumption. They are:
1. Compression blowby. This happens with these engines even in the
best of times.
2. Leaks.
3. Overfilling. This causes the crackshaft to splash in the oil in the
pan, which sprays it up onto the cylinder walls where it exceeds the
ability of the rings to contain it.
4. Positive crankcase ventilation (aka, PCV), when blowby exceeds the
ability of the engine vacuum to suck up the excess, or when the PCV
system isn't configured correctly (as with using the wrong valve
covers or with a malfunctioning PCV valve).
5. Worn valve guides, allows oil to run down into the cylinders, or
(worse) pulls a vacuum on the oiled area under the valve cover.
6. Vacuum leak into the oil gallery.
The maintenance manual, as I recall, specifies normal consumption as
one quart every 1500 miles.
Overfilling is a very common mistake, with many reporting that they
put six quarts in after an oil/filter change and losing a quart within
a few hundred miles. They don't lose oil nearly as much after that.
Solved by only putting in five quarts with a filter change, because
there is already quart trapped in the front recess of the oil pan,
which does not drain during an oil change.
Dipsticks are often mis-calibrated, which makes this problem worse.
The best way to check that is to park on a level spot, drain the oil
and replace the filter, pour in five quarts, run the engine to
distribute the oil, let it settle for a half hour or so, and then read
the dipstick. Wherever the oil is, mark that spot as "full".
Pull your plugs for inspection. If they are light tan, then you aren't
pulling a huge amount of oil through the engine at a single point. A
quart in 500 miles is probably not enough to really foul the plugs. I
had a vacuum leak into the oil gallery that pulled four quarts in 200
miles--and fouled the plug severely.
If the above procedure doesn't reveal the problem, then check for
leaks. Possible leak points include the valve covers, the timing chain
cover, the fuel-pump gasket, the oil pan, the end gaps on the intake
manifold, and the front and rear main seals. The original rear main
seal, for example, is a rope seal that just leaks because it can't
help it. The factory-style rubber seals for the intake manifold end
gaps are dreadful. Also check the elbows on the oil filler tubing. If
the lower one is cracked, oil can leak out of that one pretty easily.
Dick Paterson makes very high quality silicone replacements, as does
Jim Bounds.
Replace your PCV valve as a matter of course.
I use a quart in about 1200-1500 miles, which is considered
acceptable. My engine leaks a little through most gaskets, though I've
solved leaked at the intake end gaps, the timing chain cover, the
fuel-pump gasket, and for the front main seal. My valve covers and oil
pan still leak, and maybe the rear main seal also. My engine has
100,000 miles on it and it has a little blowby, so some oil is getting
pumped out of the breather on occasion--that breather should be the
intake for air being pulled by the PCV system. Fixing all those things
would probably eliminate most consumption as long as I don't overfill
it.
Rick "when it comes to dipsticks: Trust, but verify" Denney
'73 230 Ex-Glacier "Jaws"
Northern Virginia
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| Re: [GMCnet] reasons for using oil? [message #64526 is a reply to message #64461] |
Mon, 16 November 2009 16:21 |
KB
Messages: 1262
Registered: September 2009
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>
> Karen--what type and viscosity of oil are you using?
>
> -- Bob de Kruyff 78 Eleganza
It was Castrol Sythetic blend, though I can't recall what viscosity now.
The selection was limited, so I'd guess 15w-30. 6 quarts with a filter change.
It's not even showing on the dipstick now, so it used a lot.
I'm planning to change the oil again (it was really dirty) and put in Rotella.
Best I could find at Pep Boys today was 15w-40.
This topic has probably been covered before, so hopefully there's a FAQ somewhere I can start with.
Or maybe Steve would like to trade his 26' for my 23'. I think his already has a nice rebuilt engine :-)
Karen
1973 23' Patience Tester
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Karen
1975 26'
San Jose, CA
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| Re: [GMCnet] reasons for using oil? [message #64535 is a reply to message #64526] |
Mon, 16 November 2009 16:54 |
Rick Denney
Messages: 430
Registered: January 2004
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KB writes...
> It was Castrol Sythetic blend, though I can't recall what viscosity now.
> The selection was limited, so I'd guess 15w-30. 6 quarts with a filter change.
> It's not even showing on the dipstick now, so it used a lot.
There's your answer, at least in part. Next time, just put five quarts
in it with the filter change. Mark a new spot on the dipstick if
necessary. The capacity of the system is six quarts, but a quart gets
trapped in the front well of the oil pan. The extra quart will be
blown by the rings in short order.
Rick "noting that the maintenance manual is misleading here" Denney
'73 230 Ex-Glacier "Jaws"
Northern Virginia
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| Re: [GMCnet] reasons for using oil? [message #64618 is a reply to message #64461] |
Tue, 17 November 2009 12:15 |
kingd
Messages: 592
Registered: June 2004
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Karen, if it's off the stick in that few miles, it is using A LOT !!(could be leaking or using). Somehow you need to be able to get under the engine and see if anything looks freshly oiled, also look from above. As been said here many times, with synthetic, if it is "burning" the oil through the engine you may not see smoke out the tail pipe, but if the Rotella you are to use now is NOT synthetic, you may see lots of tail pipe smoke if that's where it's going. As Rick says, experience seems to indicate that you only need 5 quarts with filter unless you can magically drain the front of the pan. As Rick also said, there can be internal leaks that can cause lots of oil consumption but doesn't require a rebuild to fix. GOOD LUCK
Dave King in Toronto (where it was 31F this morning !!!)
DAVE KING
lurker, wannabe
Toronto, Ontario, Canada
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| Re: [GMCnet] reasons for using oil? [message #64622 is a reply to message #64618] |
Tue, 17 November 2009 12:58 |
Bob de Kruyff
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
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BTW--if you are burning that much oil, I would not use synthetic. Synthetic can create some very nasty glass-like deposits if it is burned. Besides, why spend the money for synthetic when it is disappearing that quickly. I don't see where you live, but if it is in a moderate or warmer climate, I would go to a straight 30 wt.
Bob de Kruyff
78 Eleganza
Chandler, AZ
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| Re: [GMCnet] reasons for using oil? [message #64672 is a reply to message #64622] |
Tue, 17 November 2009 18:55 |
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USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
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Bob,
Agreed; with one mod, in Double trouble I have been running Rotella T dino
and burning oil. Unfortunately I have not documented it properly but I do
know it's not serious as the plugs are a nice light tan. I intend to
calibrate the dipstick and switch over to Mobil 1 and see what happens. I
will carefully monitor my consumption and if it is high I'll switch back to
Rotella T dino to avoid the deposits.
I'm doing this because IIRC someone mentioned switching over to synthetic
and when they did their oil consumption dropped significantly.
Regards,
Rob Mueller
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Bob de Kruyff
Sent: Wednesday, 18 November 2009 5:58 AM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] reasons for using oil?
BTW--if you are burning that much oil, I would not use synthetic. Synthetic
can create some very nasty glass-like deposits if it is burned. Besides, why
spend the money for synthetic when it is disappearing that quickly. I don't
see where you live, but if it is in a moderate or warmer climate, I would go
to a straight 30 wt.
--
Bob de Kruyff
78 Eleganza
Chandler, AZ
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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
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| Re: [GMCnet] reasons for using oil? [message #64690 is a reply to message #64672] |
Tue, 17 November 2009 21:01 |
GMC_LES
Messages: 569
Registered: October 2009
Location: Montreal
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Rob,
I have used Mobil 1 in numerous different engines over the years. I have
experienced a noticeable decrease in oil consumption on just about every
engine I put M1 into. Even my garden tractor consumes less oil when I run M1
in it. I don't consider M1 a miracle cure, but if the oil consumption is
within reason with dino oil, I don't mind switching to M1. Like you, if I
see that consumption is still uncomfortably high even with M1, I switch back
to dino at the next oil change. No point pumping the M1 out the exhaust.
By the way, I purchased a gallon of the SFR 100 oil supplement. I asked the
manufacturer what the Zinc content was and they answered with 9550 ppm
straight from the bottle. This makes it easy to estimate how much you need
to add to an oil with a known zinc content. 1 oz per litre gives approx
300ppm increase if I've done my math correctly.
Les Burt
Montreal
-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Rob Mueller
Sent: November 17, 2009 7:55 PM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] reasons for using oil?
Bob,
Agreed; with one mod, in Double trouble I have been running Rotella T dino
and burning oil. Unfortunately I have not documented it properly but I do
know it's not serious as the plugs are a nice light tan. I intend to
calibrate the dipstick and switch over to Mobil 1 and see what happens. I
will carefully monitor my consumption and if it is high I'll switch back to
Rotella T dino to avoid the deposits.
I'm doing this because IIRC someone mentioned switching over to synthetic
and when they did their oil consumption dropped significantly.
Regards,
Rob Mueller
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Bob de Kruyff
Sent: Wednesday, 18 November 2009 5:58 AM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] reasons for using oil?
BTW--if you are burning that much oil, I would not use synthetic. Synthetic
can create some very nasty glass-like deposits if it is burned. Besides, why
spend the money for synthetic when it is disappearing that quickly. I don't
see where you live, but if it is in a moderate or warmer climate, I would go
to a straight 30 wt.
--
Bob de Kruyff
78 Eleganza
Chandler, AZ
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Les Burt
Montreal
1975 Eleganza 26ft
A work in Progress
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| Re: [GMCnet] reasons for using oil? [message #64694 is a reply to message #64690] |
Tue, 17 November 2009 21:17 |
Bob de Kruyff
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
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""Rob,
I have used Mobil 1 in numerous different engines over the years. I have
experienced a noticeable decrease in oil consumption on just about every
engine I put M1 into. Even my garden tractor consumes less oil when I run M1
in it. I don't consider M1 a miracle cure, but if the oil consumption is
within reason with dino oil, I don't mind switching to M1""
Although I'm a big fan of synthetic oil in most applications, on my 403, I have had the best luck by far with running straight 30 w dyno oil. I have no oil consumption even in the tough mountainous terrain in hot climates. However, AZ is a relatively safe place to use a straight viscosity. I've had the same experience with my Onan ironically. Here is a quote from the manual:
RECOMMENDED SAE VISCOSITY
Single grade oils are preferred, however, multigrades
such as SAE IOW-30 or IOW-40 are
also acceptable.
Multiviscosity oils were wide spread in the 70's but GM still recomended a straight viscosity. I know oils have changed a lot, and I'm not a purist by any means, but in my case, the recomended oil works the best by far.
7
Bob de Kruyff
78 Eleganza
Chandler, AZ
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| Re: [GMCnet] reasons for using oil? [message #64695 is a reply to message #64672] |
Tue, 17 November 2009 21:23 |
fred v
Messages: 999
Registered: April 2006
Location: pensacola, fl.
Karma: 0
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| Robert Mueller wrote on Tue, 17 November 2009 18:55 |
Bob,
Agreed; with one mod, in Double trouble I have been running Rotella T dino
and burning oil. Unfortunately I have not documented it properly but I do
know it's not serious as the plugs are a nice light tan. I intend to
calibrate the dipstick and switch over to Mobil 1 and see what happens. I
will carefully monitor my consumption and if it is high I'll switch back to
Rotella T dino to avoid the deposits.
I'm doing this because IIRC someone mentioned switching over to synthetic
and when they did their oil consumption dropped significantly.
Regards,
Rob Mueller
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
|
i tried the switch to Mobil 1 and it didn't change my consumption a bit.
Fred V
'77 Royale RB 455
P'cola, Fl
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| Re: [GMCnet] reasons for using oil? [message #64763 is a reply to message #64461] |
Wed, 18 November 2009 12:16 |
KB
Messages: 1262
Registered: September 2009
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Well, got under there yesterday to change the oil and filter and,
wow, what a mess! Yes, I knew it was dirty before, but I can now
see fresh oil all over the place. Didn't see more than a drip or so on the
cardboard underneath though, so that's a bit odd. I changed the gasket
on the oil cooler extension above the filter -- it looked like it had never been
changed before so was a source of leaks for sure. The old gasket was thin, crumbly, and
mostly gone. But, the worst of it is probably the oil pan gasket which, if I
understand it, is a *real* pain to change. Guess I'll be living with leaks
for a long time... Impossible to say if it's burning oil too.
Time to start buying those 5-gallon buckets of oil!
thanks,
Karen
1973 23' Patience Tester
> From: Dave King <kingd@sympatico.ca>
> Subject: Re: [GMCnet] reasons for using oil?
> To: gmclist@temp.gmcnet.org
> Message-ID: <fc6a.4b02e846@gmc.mybirdfeeder.net>
> Content-Type: text/plain; charset="ISO-8859-15"
>
>
>
> Karen, if it's off the stick in that few miles, it is using A LOT !!(could be leaking or using). Somehow you need to be able to get under the engine and see if anything looks freshly oiled, also look from above. As been said here many times, with synthetic, if it is "burning" the oil through the engine you may not see smoke out the tail pipe, but if the Rotella you are to use now is NOT synthetic, you may see lots of tail pipe smoke if that's where it's going. As Rick says, experience seems to indicate that you only need 5 quarts with filter unless you can magically drain the front of the pan. As Rick also said, there can be internal leaks that can cause lots of oil consumption but doesn't require a rebuild to fix. GOOD LUCK
> Dave King in Toronto (where it was 31F this morning !!!)
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Karen
1975 26'
San Jose, CA
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| Re: [GMCnet] reasons for using oil? [message #64765 is a reply to message #64461] |
Wed, 18 November 2009 12:30 |
fred v
Messages: 999
Registered: April 2006
Location: pensacola, fl.
Karma: 0
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you need to wipe it dry and clean then crank it up and get under there and look for leaks in the oil cooler hoses going up to the rad. they have a way of cracking open after so many years. look for other leak sources with oil pressure up. look at the front and rear crankshaft seals and the filter mount. look at the valve covers. they leak down onto the exhaust manifolds.
the oil pan may just be oil that has dripped or squirted on the pan. you cannot get a tool on the pan bolts on the left side without moving the tranny over.
good luck,
Fred V
'77 Royale RB 455
P'cola, Fl
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| Re: [GMCnet] reasons for using oil? [message #64768 is a reply to message #64763] |
Wed, 18 November 2009 12:46 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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| KB wrote on Wed, 18 November 2009 12:16 |
Well, got under there yesterday to change the oil and filter and,
wow, what a mess! Yes, I knew it was dirty before, but I can now
see fresh oil all over the place. Didn't see more than a drip or so on the
cardboard underneath though, so that's a bit odd. I changed the gasket
on the oil cooler extension above the filter -- it looked like it had never been
changed before so was a source of leaks for sure. The old gasket was thin, crumbly, and
mostly gone. But, the worst of it is probably the oil pan gasket which, if I
understand it, is a *real* pain to change. Guess I'll be living with leaks
for a long time... Impossible to say if it's burning oil too.
Time to start buying those 5-gallon buckets of oil!
thanks,
Karen
1973 23' Patience Tester
|
Wash the engine and trans down. Engine cleaner and water works. Also Simple Green and a water rinse works well. I have also used stoddard solvent or a few cans a brake cleaner.
Once it is clean and you run the engine again, you will be able to see where the leaks are coming from. Odds are that they are not coming from the pan gasket. Almost any leak from other places will eventually end up on the oil pan.
Good luck.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: [GMCnet] reasons for using oil? [message #64792 is a reply to message #64763] |
Wed, 18 November 2009 14:50 |
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Matt Colie
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
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| KB wrote on Wed, 18 November 2009 13:16 |
Well, got under there yesterday to change the oil and filter and, wow, what a mess! Yes, I knew it was dirty before, but I can now see fresh oil all over the place. Didn't see more than a drip or so on the cardboard underneath though, so that's a bit odd. I changed the gasket on the oil cooler extension above the filter -- it looked like it had never been changed before so was a source of leaks for sure. The old gasket was thin, crumbly, and mostly gone. But, the worst of it is probably the oil pan gasket which, if I understand it, is a *real* pain to change. Guess I'll be living with leaks for a long time... Impossible to say if it's burning oil too.
Time to start buying those 5-gallon buckets of oil!
thanks,
Karen
1973 23' Patience Tester
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Karen,
Actually, oil all over and few drip on the floor is common for a leak from a pressure source - like the oil cooler adapter. You may well have fixed your real problem already.
If you think you have a pan gasket leak, while you are under there anyway.... Check the pan bolts.
They are very VERY easy to over tighten, but it is also common for them to lose tension all on their own. (Actually, it is the creep in the assembly that does it.)
So, take a the sockets (7/16 & 1/2) a long extension and a ratchet and go around the pan carefully. Put the extension between two fingers so you can't get too much torque on the fastener and give each a tweak. The spec torque is "not very much" ~10#ft. If you over tighten them, you may crush the gasket and distort the pan edge.
When you think of it, do the same to the valve gear covers.
This is a common problem with engines of this vintage. I've had a few "Fill up the oil and check the gas" cars of my own.
Good Luck
Matt Colie
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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| Re: [GMCnet] reasons for using oil? [message #64807 is a reply to message #64763] |
Wed, 18 November 2009 16:10 |
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Karen,
Was nice to meet you at the rally last weekend. As to your oil leak issues,
been there, done that. Like several folks pointed out, the oil cooler
lines (mine burst),
any adapters/reducers on the oil cooler lines where they go into the
radiator (they loosen up)
and the o-ring between the oil cooler adapter and the block (replace
with one off of an old
oil filter). Loose valve cover bolts.
Terry Taylor
74 ex-Eleganza SE
San Lorenzo, CA
KB wrote:
> Well, got under there yesterday to change the oil and filter and,
> wow, what a mess! Yes, I knew it was dirty before, but I can now
> see fresh oil all over the place. Didn't see more than a drip or so on the
> cardboard underneath though, so that's a bit odd. I changed the gasket
> on the oil cooler extension above the filter -- it looked like it had never been
> changed before so was a source of leaks for sure. The old gasket was thin, crumbly, and
> mostly gone. But, the worst of it is probably the oil pan gasket which, if I
> understand it, is a *real* pain to change. Guess I'll be living with leaks
> for a long time... Impossible to say if it's burning oil too.
> Time to start buying those 5-gallon buckets of oil!
>
> thanks,
> Karen
> 1973 23' Patience Tester
>
>
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Terry Taylor
'74 ex-Eleganza SE
San Lorenzo, CA
http://www.n6mon.org
http://dldesignstore.com
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| Re: [GMCnet] reasons for using oil? [message #64818 is a reply to message #64792] |
Wed, 18 November 2009 17:38 |
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USAussie
Messages: 15912
Registered: July 2007
Location: Sydney, Australia
Karma: 6
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Senior Member |
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Matt,
As I understand it the problem that you run into trying to tighten the pan
bolts is you can't get to the ones above the final drive. If that is
incorrect PLEASE correct me!
Dick Paterson suggested that I clean the area and run a bead of silicone
down the joint. I decided just to bite the bullet and drop the trans and
final drive and replace it.
Since I would have the pan off I decided to install an oil pan with a drain
for the front section like the one that came with my Caddy 500. Got a pan
from Michael Bozardt and had a nut welded on the inside of the pan under the
main bearing cap where it wouldn't get hit by the connecting rods.
I agree that one must be careful not to over tighten the pan bolts as it
deforms the pan! I had to tap quite a few of the areas around the bolt holes
back "down" to flatten the sealing surface.
Bob Drewes suggested that I use an oil pan gasket from a 350 Olds as it has
a metal core and won't deform when tightened.
I didn't check to see if the rear main seal was leaking yet but I will do so
(obviously) before I drop the pan. I checked MM X-7525 Page 6A-61 and noted
that replacing the rear main seal is an "Out of Vehicle Service Operation."
I vaguely remember back in my teenage years changing rope rear main seals in
vehicles by removing all the main bearing caps, dropping the crank enough to
remove the old seal and using a Chinese finger type tool to pull the new one
through.
Queries:
1) has anyone done this?
2) is it a good idea or should I bite the bullet and remove the crank
completely if I have to replace the rear main seal?
Regards,
Rob Mueller
Sydney, Australia
AUS '75 Avion-The Blue Streak TZE365V100428
USA '75 Avion-Double Trouble TZE365V100426
-----Original Message-----
From: gmclist-bounces@temp.gmcnet.org
[mailto:gmclist-bounces@temp.gmcnet.org] On Behalf Of Matt Colie
Sent: Thursday, 19 November 2009 7:50 AM
To: gmclist@temp.gmcnet.org
Subject: Re: [GMCnet] reasons for using oil?
Karen,
Actually, oil all over and few drip on the floor is common for a leak from a
pressure source - like the oil cooler adapter. You may well have fixed your
real problem already.
If you think you have a pan gasket leak, while you are under there
anyway.... Check the pan bolts.
They are very VERY easy to over tighten, but it is also common for them to
lose tension all on their own. (Actually, it is the creep in the assembly
that does it.)
So, take a the sockets (7/16 & 1/2) a long extension and a ratchet and go
around the pan carefully. Put the extension between two fingers so you
can't get too much torque on the fastener and give each a tweak. The spec
torque is "not very much" ~10#ft. If you over tighten them, you may crush
the gasket and distort the pan edge.
When you think of it, do the same to the valve gear covers.
This is a common problem with engines of this vintage. I've had a few "Fill
up the oil and check the gas" cars of my own.
Good Luck
Matt Colie
--
Matt & Mary Colie
'73 Glacier 23 Chaumiere (say show-me-air)
SE Michigan
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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
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