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Discussion Starter · #1 ·
Just curious if others have oil burning issues with the GM v6.

My 3.1L has 140k on it and loses 1qt/1,000 miles. I haven't seen any oil drips on the ground so I assume it's burning it although I've never seen it smoke. I use standard 10-30 oil.

What have you guys experienced? Ideas to decrease oil consumption?
 

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Oil consumption not a problem in a tight 2.8 or 3.1. They won't always smoke even if they are burning oil. You Cat. will eventually clog though. Run a compression test.
 

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It is not common but any engine can become an oil burner. Cheap oil makes the problem worse.

I would try the Rotella oil others on this board are using on the 3.5/3.2 oil burners.

Also valve stem seals on the intake can get old and loose and will allow oil to bleed down into the cylinder. Also the intake us under vacuum so a slightly worn guide will allow vacuum so simply suck oil into the intake. If you notice blue smoke on startup its time to investigate those seals.

Just note that badly worn guides will wipe new seals out the first time it runs so you need to check the slop with the springs off. If they check out ok then install new Viton valve stem seals. Buy a set for the exhaust also. They don't come with them stock but adding them improves sealing on the exhaust. You can then ditch the oil control umbrella that is under the exhaust retainer.
 

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Discussion Starter · #4 ·
I'll check the valve seals and slop when I replace the valve covers and do a compression check at the same time. I haven't noticed smoke on start up.

What should the compression psi be?

Thanks for the feedback.
 

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I think I was 2,000 miles over on my last oil change and was still in the OK range... my 3.1 has somewhere around 260k on it. :wink:
 

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Discussion Starter · #7 ·
Ruination said:
I think I was 2,000 miles over on my last oil change and was still in the OK range... my 3.1 has somewhere around 260k on it. :wink:
That's nuts! You have a solid motor. I'll check the compression and go from there.
 

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I have done the valve seal change on two of my troopers. One was even fouling a plug. You could never see any smoke and the plugs looked normal. If you are going under the valve covers do it right the first time.
Replace the valve springs with early 327 springs, install a set of roller rockers and install Pontiac Fiero aluminum valve covers with the silicone seals. Engine will not leak any more, will rev better then new and burn no oil.

John in Marysville
 

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Discussion Starter · #9 ·
I just ordered the Fiero valve covers. Where did you buy the valve springs, roller rockers and silicone seals?

I'll do the plugs, wires, rotor, etc when I do the project. Also, probably change the hoses and water pump.

Any recommendation for water pump? Dealer wants about $200 for one. I don't trust most aftermarket parts but any you guys would recommend?
 

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Do a search for Comp Cams #1414-12 find the best prices.
http://www.summitracing.com/parts/CCA-1414-12/

Geoff Moore (betterthenyou) did a good write up on installing the valve covers.
http://members.shaw.ca/betterthanyoutoo ... covers.htm I used FelPro Gaskets

I buy parts from Ebay, Rockauto, and Autozone depending on the price and how fast I want them. Hardly ever buy parts from the stealership.

If you are going to do a water pump you might as well do a timing chain and dampner.

GM Part Numbers 12363215 â€" Valve Spring
This valve spring is used in the new 3.4-liter engine conversion package
(P/N 12363230) and designed for moderate performance usage.
Manufactured from chrome silicon wire, this spring produces 105 pounds of
seat pressure at an installed height of 1.70" and 296 pounds open pressure
at a height of 1.20".
Technical Note: Use with retainer P/N 12363216 "

These are the springs I ended up using--

1.25" OD early Z28 Lt1 springs. Both Crane and Comp Cams use these springs with there 60* v-6 cam kits. The last two sets of springs I got off Ebay with locks and retainers for $40 each.

All this depends on a good compression test, no use throwing money into a block with warn out rings.

I have 265K miles on the engine now. I put a new timing chain and valve springs and seals on when High oil consumption started at about 140K miles.

Hope this helps
 

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Discussion Starter · #11 ·
That is extremely helpful. Thank you for the valve cover link too (excellent write up Geoff). I'll keep you guys posted when I dig into it in a month or so.

Do the timing chains go bad? I thought it would be a non-issue with a push rod motor.

How much oil where you going through at 140K?
 

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Timing Chains stretch and brake the Dampner that is mounted between the cam and crank. The slack will cause your timing to change with acceleracion and deceleracion.

I was going thru 1/2 quart every 1000 Miles depending on how much time I spent above 3000 RPM.

Look into replacing the distributor O-ring and puting a new coating of dielectric compound on the bottom of the ignition modual in the distributor.

John
 

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Discussion Starter · #13 ·
This is starting to sound like a big project. I'll let you guys know what I find out from the compression check.

I really appreciate your advise John. Thanks.

-Peter
 

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Break it up into two phases. One the valve related items. Two the timing chain, water pump and hose items.
 

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Discussion Starter · #15 ·
Soo.... Finally pulled the plugs and tested the compression. Here are the results:

Rear Pass - Rear Driver
110 - 120
110 - 120
90 - 110

I didn't wet test the rings as I'll replace the motor before doing just the heads. Sure runs good for such low numbers (assuming my gauge is accurate).
 

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I had 180K on my old 2.8 and it used not a drop of oil. But it sure leaked it. I built myself an engine from the ground up from a 3.1 I got from John a year or so ago. I even bought a set of heads from him. He knows what he is talking about. Betterthanyou is what I based my engine from. Solid information. If you can, find a 3.4 and start with that. It is as close to a bolt in you can find that can really run circles around the old 2.8. I pumped up my 3.1 to about a 3.2 and I am happy with that.
Good luck and keep us posted!
Dick
 

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littlegray said:
Soo.... Finally pulled the plugs and tested the compression. Here are the results:

Rear Pass - Rear Driver
110 - 120
110 - 120
90 - 110

I didn't wet test the rings as I'll replace the motor before doing just the heads. Sure runs good for such low numbers (assuming my gauge is accurate).
Was the throttle open and the plugs removed from all other cylinders?
 

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Discussion Starter · #18 ·
I had all the passenger plugs pulled. The driver side had one plug pulled at a time. It was closed throttle. I watched the gauge and kept cranking until the needle stopped moving. How do you recommend doing it?

Yes. I think the 3.4L swap will be the direction I look to go.
 

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Remove all the plugs from the motor and have the person who is cranking the motor over hold the throttle open when you run the test. I would recommend disconnecting the injectors too.

If the starter cannot spin the motor at a proper speed you will not get a good reading.
 

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I didn't have anyone to help me when I did mine, I just rigged up a rubber bungie to the Throttle body to keep the butterflys open. Like betterthanyou said remove all the plugs so its balanced out right and I just pulled the fuel pump fuse so I wasn't dumping fuel at the same time.
 
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