OUCH Bad Oil Analysis

C

corey

New member
Jan 7, 2010
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0
Sent my first sample from the coach to Blackstone.

http://www.gmcmhphotos.com/photos/oil-analysis/p67855-oil-analysis-redacted.html

This analysis is from the first oil fill after purchasing the coach last winter (I changed the oil in March and this is the oil that was put in at
that time). I know that the coach accumulated just a few miles over the course of the last 15 years, and as far as I know the oil that was in there
before march had been in there the whole time. I do NOT know if the PO ever started and ran the coach or if it just sat. Never got to meet PO, coach
was bought at auction yard. I did not bother to pre-oil as the coach had been driven onto and off of the trailer to get to the yard (and I probably
wouldn't have had the wisdom to do that at that time anyways). One note: I found out during that oil change that the dipstick was incorrect. I
estimate around only 2.5 quarts actually came out of the pan/oil filter. The coach was driven a few times to test things before I discovered this,
including on the highway. I was religiously watching the aftermarket oil pressure gauge which was always above 40 at speed and as low as 30 hot idle.
Never saw so much as a blip. Since then, I am putting 5 quarts in during oil change and marking that spot on the dipstick.

Mostly just bumming out, but I do have one question for the group... I did install new stainless oil cooler lines and an oil temp sensor inside the
oil filter adapter (brass piece drilled and tapped into aluminum, obviously cleaned out the adapter before re-installing). Could these high metals be
because of this work?

The coach does seem to use some oil but I'm not 100% sure how much since I did drain some of the oil doing the aforementioned work. And obviously I
can't trust the dipstick. Compression test last winter showed 150 psi all around. Going to do another one this weekend.

Winter is my slow time so I am trying to figure out where I can drive to get 1,000 mi round trip quickly so that I can get another sample ASAP. All
while avoiding as much road salt as possible.
--
Corey P /

Hilliard, OH /
1974 Glacier 26' /
3.70 FD /
ION Wheels
 
So Cory,
Try this, a couple of friends (and I) have done this with positive results. Doesn't always work, depends on how much damage has been done to this
point. You can try flushing the whole system. Go to Walmart or Fleet Farm or some place where you can buy oil cheap. Buy three 5qt pails of
5w30...stuff on sale, and 3 cheap oil filters. (Fram would work for this). Then do 3 quick oil changes. After each change, take the coach out for an
EASY 10mi drive. For the 4th change, put in whatever oil you intend to run with a Wix oil filter, like maybe Valvoline 10w40 synthetic blend
formulated for older engines in the Red bottle. Then drive it 1000 miles and do your next Blackstone test. The three changes with a short easy drive
will flush the system out. Then the next 1000miles will provide you with a relatively accurate look at what kind of wear is taking place in a
relatively clean engine. JWID
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
I did Larry's 3 oil change flush on my newly rebuilt engine.=C2=A0 After my=
first trip with it I thought I had an engine problem so I did the 3 flushe=
s.=C2=A0 That made a significant difference and I now have 9,000 miles on t=
he new engine and it's running great (knock on wood).Definitely give the fl=
ushing a try.Sent from my U.S.Cellular=C2=A9 Smartphone -------- Origina=
l message --------From: Larry via Gmclist Date: 1=
2/18/20 5:12 PM (GMT-06:00) To: gmclist Cc: Larry Subject: Re: [GMCnet] OUCH Bad Oil Analysis So Cory,Try this, a=
couple of friends (and I) have done this with positive results. Doesn't al=
ways work, depends on how much damage has been done to thispoint. You can t=
ry flushing the whole system. Go to Walmart or Fleet Farm or some place whe=
re you can buy oil cheap. Buy three 5qt pails of5w30...stuff on sale, and 3=
cheap oil filters. (Fram would work for this). Then do 3 quick oil changes=
.=C2=A0 After each change, take the coach out for anEASY 10mi drive. For th=
e 4th change, put in whatever oil you intend to run with a Wix oil filter,=
=C2=A0 like maybe Valvoline 10w40 synthetic blendformulated for older engin=
es in the Red bottle. Then drive it 1000 miles and do your next Blackstone =
test. The three changes with a short easy drivewill flush the system out. T=
hen the next 1000miles will provide you with a relatively accurate look at =
what kind of wear is taking place in arelatively clean engine. JWID-- Larry=
=C2=A0 78 Royale w/500 CaddyMenomonie, WI._________________________________=
______________GMCnet mailing listUnsubscribe or Change List Options:http://=
list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Did similar oil change with mine.
Topped up oil, Mobil 1, and kept it full for a 400 mile drive home. Wish I changed oil and filter first.
First two oil change with all the odd leftovers in my garage short trips less than 100 miles.
Amazing all the crap in the filter each change. Looked like the PO added sand with his oil.
Then Mobil 1 changed every 500 miles first year. Now about every 2000 miles. Never had it tested at Blackstone maybe next time.

--
1977 Kingsley 455 as stock as it gets except lots of Ragusa parts
 
No nickel so might not be block wear.
--
1977 Kingsley 455 as stock as it gets except lots of Ragusa parts
 
Did you have a magnet in the oil plug? Cut open the oil filter and lastly how is the hot idle oil pressure?

Going forward; carefully check the air filter for damage and distorted sealing surfaces. If you are using a K+N, well not my first choice.

Watch oil and coolant consumption and use a good filter. Torque intake manifold.

I prefer a Group IV synthetic oil (made from natural gas). You can't undo the past. Keep air and fuel pure, coolant out of the oil. You have
good compression. A little oil consumption from a stored engine is not abnormal.

Watch all and report back.

A plumber once told me there was nothing his talent and my checkbook that couldn't be fixed.
--
1977 Eleganza II
Ogden NY
 
Each time you do a crankcase oil and filter change and put a number of miles on the engine I would cut open the filter and inspect it for traces of
metal in the media.
--
Roy Keen
Minden,NV
76 X Glenbrook
 
Sir, just a side note. The oil change is 6 quarts with a filter.

> Sent my first sample from the coach to Blackstone.
>
> http://www.gmcmhphotos.com/photos/oil-analysis/p67855-oil-analysis-redacted.html
>
> This analysis is from the first oil fill after purchasing the coach last winter (I changed the oil in March and this is the oil that was put in at
> that time). I know that the coach accumulated just a few miles over the course of the last 15 years, and as far as I know the oil that was in there
> before march had been in there the whole time. I do NOT know if the PO ever started and ran the coach or if it just sat. Never got to meet PO, coach
> was bought at auction yard. I did not bother to pre-oil as the coach had been driven onto and off of the trailer to get to the yard (and I probably
> wouldn't have had the wisdom to do that at that time anyways). One note: I found out during that oil change that the dipstick was incorrect. I
> estimate around only 2.5 quarts actually came out of the pan/oil filter. The coach was driven a few times to test things before I discovered this,
> including on the highway. I was religiously watching the aftermarket oil pressure gauge which was always above 40 at speed and as low as 30 hot
> idle. Never saw so much as a blip. Since then, I am putting 5 quarts in during oil change and marking that spot on the dipstick.
>
> Mostly just bumming out, but I do have one question for the group... I did install new stainless oil cooler lines and an oil temp sensor inside
> the oil filter adapter (brass piece drilled and tapped into aluminum, obviously cleaned out the adapter before re-installing). Could these high
> metals be because of this work?
>
> The coach does seem to use some oil but I'm not 100% sure how much since I did drain some of the oil doing the aforementioned work. And obviously
> I can't trust the dipstick. Compression test last winter showed 150 psi all around. Going to do another one this weekend.
>
> Winter is my slow time so I am trying to figure out where I can drive to get 1,000 mi round trip quickly so that I can get another sample ASAP.
> All while avoiding as much road salt as possible.

--
C. Boyd
76 Crestmont
East Tennessee
 
> Sent my first sample from the coach to Blackstone.

Tiz true....but for the three "quick" oil changes and a "easy" 10 mile drive, no need to add that 6th quart. Definitely though...add that 6th quart
for the 1000 mile Blackstone test. JWID
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Well, more bad news... did a compression check and cylinder #4 is about 90 psi, others were all 135-140. Oil squirt into the spark plug hole brought
psi up to 150
--
Corey P /

Hilliard, OH /
1974 Glacier 26' /
3.70 FD /
ION Wheels
 
> Well, more bad news... did a compression check and cylinder #4 is about 90 psi, others were all 135-140. Oil squirt into the spark plug hole
> brought psi up to 150

That doesn't mean the engine isn't driveable. 90psi is not that terrible. Do the oil changes and drive it 1K, and see what happens. JWID
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Try adding a teaspoon of 90 weight oil and retest. Does it go up?

>
> Well, more bad news... did a compression check and cylinder #4 is about 90 psi, others were all 135-140. Oil squirt into the spark plug hole brought
> psi up to 150
> --
> Corey P /
>
> Hilliard, OH /
> 1974 Glacier 26' /
> 3.70 FD /
> ION Wheels
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Oops. I didn’t finish my email. If you added the oil and it went up, then it is likely cylinder/ring related. Try adding a teaspoon of sea foam, Berryman’s B-12 or another fuel system cleaner. Let it soak for a few minutes, replace the it install the compression tester and repeat a few times. The cleaner will soak down through the rings and soften any glaze that may make the ring not seal as well. I have had great success with this method, and it doesn’t cost much to try.

>
> Well, more bad news... did a compression check and cylinder #4 is about 90 psi, others were all 135-140. Oil squirt into the spark plug hole brought
> psi up to 150
> --
> Corey P /
>
> Hilliard, OH /
> 1974 Glacier 26' /
> 3.70 FD /
> ION Wheels
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
I simply can’t get an email through from my phone today. “Let it soak for a few minutes, replace the spark plug or install the compression tester, crank it over a little, and repeat a few times.”
 
Carburated engines present some unique factors that can affect compression test results.
-The quadrajet is known for leaky bottom plugs which can allow fuel to drip into the intake and possibly end up in a cylinder.
-Repeatedly opening and closing throttle during each cylinder test will operate the accelerator pump, dumping raw fuel into the intake and cylinders.
-Cranking with spark plugs removed still draws air through the carb, pulling an amount of fuel out of the carb and downstream into the cylinders.

All these factors can result in fuel-washed cylinder walls that will reduce ring sealing.

Because of the above factors, It is always preferable to perform compression test results on an engine that has just been driven several miles to fully warm it up. This ensures excess fuel has been burned away and lube oils have been distributed as thoroughly as possible on the cylinder walls. This puts the engine closer to normal operating conditions, providing results which are more representative of operational engine health.

Not all engines can be run under the ideal circumstances, so cold compression testing is often done to help diagnosis. The results can be easily mis-interpreted if the other factors are not considered.

I would follow the recommendations to drive it 1000 miles and then re-evaluate engine health.

Les Burt
Montreal
'75 Eleganza 26'

>
> I simply can’t get an email through from my phone today. “Let it soak for a few minutes, replace the spark plug or install the compression tester, crank it over a little, and repeat a few times.”
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
When you have one cylinder that tests low compared to the rest, it is never
a good omen. If compression is nearly restored with squirting oil in
through the spark plug hole, then it is very likely that you have a ring
and piston issue. Metal in the drain oil is all the confirmation that is
necessary. It is time to pull the head on that side and inspect that
cylinder carefully. Lots of causes here. On new engines, it almost always
traces back to sloppy, careless engine assembly. Old ones, wear. In any
event, time for some engine work.
Jim Hupy
Salem, Oregon

On Sat, Dec 19, 2020, 8:08 AM Les Burt via Gmclist
wrote:

> Carburated engines present some unique factors that can affect compression
> test results.
> -The quadrajet is known for leaky bottom plugs which can allow fuel to
> drip into the intake and possibly end up in a cylinder.
> -Repeatedly opening and closing throttle during each cylinder test will
> operate the accelerator pump, dumping raw fuel into the intake and
> cylinders.
> -Cranking with spark plugs removed still draws air through the carb,
> pulling an amount of fuel out of the carb and downstream into the
> cylinders.
>
> All these factors can result in fuel-washed cylinder walls that will
> reduce ring sealing.
>
> Because of the above factors, It is always preferable to perform
> compression test results on an engine that has just been driven several
> miles to fully warm it up. This ensures excess fuel has been burned away
> and lube oils have been distributed as thoroughly as possible on the
> cylinder walls. This puts the engine closer to normal operating conditions,
> providing results which are more representative of operational engine
> health.
>
> Not all engines can be run under the ideal circumstances, so cold
> compression testing is often done to help diagnosis. The results can be
> easily mis-interpreted if the other factors are not considered.
>
> I would follow the recommendations to drive it 1000 miles and then
> re-evaluate engine health.
>
> Les Burt
> Montreal
> '75 Eleganza 26'
>
>
> > On Dec 19, 2020, at 9:17 AM, Dave Stragand via Gmclist <

> >
> > I simply can’t get an email through from my phone today. “Let it soak
> for a few minutes, replace the spark plug or install the compression
> tester, crank it over a little, and repeat a few times.”
> > _______________________________________________
> > 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
>
 
I was able to get into cylinder #4 with a borescope and have a few photos to share. They are all looking in the same general direction - at the
inboard/uphill side of the cylinder (sorry for the crooked camera orientation). All from cylinder #4.

http://www.gmcmhphotos.com/photos/oil-analysis/p67857-12-20-photo-2.html

http://www.gmcmhphotos.com/photos/oil-analysis/p67859-capture21.html

You can see that there are bright lines and are roughly horizontal but not totally parallel with each other. And directly below those bright lines is
a dark pattern on the piston top and cylinder wall.

I have a guess in my mind as to what has happened here but would like to hear everyone else's thoughts.
--
Corey P /

Hilliard, OH /
1974 Glacier 26' /
3.70 FD /
ION Wheels
 
Hmmm. Looks at first glance, to me, like a broken piston ring. So now, how
to proceed. Can't get the piston and rod out with the transmission in
place, or pulling the engine out through the top, so the pan can be
removed. That kinda outlines what needs to happen. Or, do nothing at all,
cross your fingers and hope that broken ring stays put, and just put oil in
it and drive it till something dire happens. It will. But when? $40.00
question.
Jim Hupy
Salem, Oregon

On Sun, Dec 20, 2020, 2:35 PM Corey via Gmclist
wrote:

> I was able to get into cylinder #4 with a borescope and have a few photos
> to share. They are all looking in the same general direction - at the
> inboard/uphill side of the cylinder (sorry for the crooked camera
> orientation). All from cylinder #4.
>
> http://www.gmcmhphotos.com/photos/oil-analysis/p67857-12-20-photo-2.html
>
> http://www.gmcmhphotos.com/photos/oil-analysis/p67859-capture21.html
>
> You can see that there are bright lines and are roughly horizontal but not
> totally parallel with each other. And directly below those bright lines is
> a dark pattern on the piston top and cylinder wall.
>
> I have a guess in my mind as to what has happened here but would like to
> hear everyone else's thoughts.
> --
> Corey P /
>
> Hilliard, OH /
> 1974 Glacier 26' /
> 3.70 FD /
> ION Wheels
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
> Hmmm. Looks at first glance, to me, like a broken piston ring. So now, how to proceed. Can't get the piston and rod out with the transmission in
> place, or pulling the engine out through the top, so the pan can be removed. That kinda outlines what needs to happen. Or, do nothing at all, cross
> your fingers and hope that broken ring stays put, and just put oil in it and drive it till something dire happens. It will. But when? $40.00
> question.
> Jim Hupy

Corey,

I bet if I thought about it real hard I could think of many three times in the last 15 years I did not completely agree with Jim......

Just so you know, that knotch in the piston is the "front" identifier.

The resolution could be better, but let's go with what we have.
Those bright lines could well be where rings rested when the engine was sitting to long "unstored". It takes a lot of piston problem to make
compression that low, but a bad valve will do it in a jiffy. I wish it wasn't #4. That is the side with the A/C pump on it. That can be undone and
hung from the cab floor.
Then you can get the cylinder head cover off and tap on those valves and see if you can get one (probably the exhaust) to seat better.

My engine broke the lands of 120° of piston. A lot of the rings were in the pan. It was burning oil like a 2-stroke, but the compression was still
better than that.

Do you have the mirror attachment so the camera can look back over its shoulder? Because if it is a bad exhaust valve, taking it apart now could save
you a lot of money and work and parts. You can do heads with the clock in place.

Here's my bet....
Pump a bunch of oil into that cylinder. Do another cranking compression. If the number is a bunch better, maybe it is the piston. If, on the other
hand it is not, then it is valve problem. Tapping on the valve can sometimes clear what is on the seat and make it passable again. Sometimes not
too.

Of course now it is cold in Ohio and you can get but if you heat the interior of the coach, but no bets. I can't work with real gloves on, and my
hands get bad below 50°. Keep us informed where you are and what you find. We can offer advice all along the way that can save you grief.

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
 
Matt, he has already done a wet/dry compression check. It came up quite a
bit after the cylinder was oiled. If it had remained unchanged, I would
have suggested bad valve sealing instead of rings.
Yes, pulling that head probably should be done. Yes, that A.C.
compressor is a royal pain in the backside. If it is a high mileage engine,
the heads will need work anyway. Never seen one that could not benefit from
seats, valves and guides. Smogger heads have induction hardened valve
seats, and won't stand for a whole lot of cutting or grinding on. But, you
already already know this. I usually just bite the bullet and replace the
exhaust valve seats, I will only use hardened seats specifically made for
Oldsmobile Engines. If the ones made for big block chevs are used,
sometimes you will hit water on the Oldsmobile. Don't ask me how I found
that out. Spendy lesson learned the hard way.
If that engine sat unused for a long period of time, that ring could
be stuck in the groove, but those marks in the cylinder came from
somewhere. Just my guess at this point.
Jim Hupy
Salem, Oregon

On Sun, Dec 20, 2020, 4:21 PM Matt Colie via Gmclist <

> > Hmmm. Looks at first glance, to me, like a broken piston ring. So now,
> how to proceed. Can't get the piston and rod out with the transmission in
> > place, or pulling the engine out through the top, so the pan can be
> removed. That kinda outlines what needs to happen. Or, do nothing at all,
> cross
> > your fingers and hope that broken ring stays put, and just put oil in it
> and drive it till something dire happens. It will. But when? $40.00
> > question.
> > Jim Hupy
>
> Corey,
>
> I bet if I thought about it real hard I could think of many three times in
> the last 15 years I did not completely agree with Jim......
>
> Just so you know, that knotch in the piston is the "front" identifier.
>
> The resolution could be better, but let's go with what we have.
> Those bright lines could well be where rings rested when the engine was
> sitting to long "unstored". It takes a lot of piston problem to make
> compression that low, but a bad valve will do it in a jiffy. I wish it
> wasn't #4. That is the side with the A/C pump on it. That can be undone
> and
> hung from the cab floor.
> Then you can get the cylinder head cover off and tap on those valves and
> see if you can get one (probably the exhaust) to seat better.
>
> My engine broke the lands of 120° of piston. A lot of the rings were in
> the pan. It was burning oil like a 2-stroke, but the compression was still
> better than that.
>
> Do you have the mirror attachment so the camera can look back over its
> shoulder? Because if it is a bad exhaust valve, taking it apart now could
> save
> you a lot of money and work and parts. You can do heads with the clock in
> place.
>
> Here's my bet....
> Pump a bunch of oil into that cylinder. Do another cranking compression.
> If the number is a bunch better, maybe it is the piston. If, on the other
> hand it is not, then it is valve problem. Tapping on the valve can
> sometimes clear what is on the seat and make it passable again. Sometimes
> not
> too.
>
> Of course now it is cold in Ohio and you can get but if you heat the
> interior of the coach, but no bets. I can't work with real gloves on, and
> my
> hands get bad below 50°. Keep us informed where you are and what you
> find. We can offer advice all along the way that can save you grief.
>
> 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
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
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