Cracked Head 1991 Saturn

I picked up a beater car and I suspect it has a cracked head. The coolant looks frothy and there is oil getting into the number 1 and 2 cylinders (plugs oily). It is vey little oil, but builds up as it sits. The car stutters at very low load as if compression was zig-zagging up and down. At full throttle it acts quite well with no noticable smoke (no noticable oil in coolant or vice versa).

How hard is it to pull the head and repair it? Is there a common crack point? I know this is a common problem. I'm more interested in knowing if it just a few hours to pull and JB weld the crack. My worry is, that being a Chevy, it is hard to do. It *looks* like a primitive engine, but Chevy has a tendency to put bolts and things at very hard to reach places.

Reply to
Nobody U. Know
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(is this a the LL0 or L24? aka SingleCam or TwinCam)

It is not a Chevy and careful with your "primitive" remarks as that is trolling. No other GM cars use a LL0 or L24. I dont know what engines you've worked on but I have always found GM cars MUCH easier to work on than any other maker out there and old Saturns arent half bad. (The new Ecotecs have are the best)

First off dont go skipping simple diagnostic procedures only to find out "what you thought" wasnt "what was wrong". 91's have not been known to crack.(likely you picked up some ill informed crap by a troll in this group) Do a pressure test on your cooling system. That is by far easier than jumping right into pulling off a head which to me, doesnt sound like it is a problem.

It sounds to me that your "Valve Cover" isnt sealing anymore around the plugs and the oil is shorting out the spark. The frothy coolant you're seeing is likely Ginger Root put in there by Saturn from the factory. If you havent changed your coolant in 2 or more years then you are DUE! Get it done! And be sure to purge the air out of the system.

(Now if you want to see primitive engines look at land rovers crap, or honda with their cap and rotors.)

Reply to
blah blah

I wish my Saturns WERE Chevys. Saturn is owned by GM but is an orphan. Saturn parts are not available from my standard GM parts dealer. I think THIS is why fuel filters and block heaters are over $100 ea from Saturn.

My understanding was that it was 95 and 96 heads that had the casting flaws and resulted in cracks. I concur with blah blah, do the simple stuff first before you go tearing into the head. I doubt that JB weld would be a reliable repair and would be more inclined to find a good used head and have a valve grind and guide repair before installation if required. I suspect that would be cheaper than trying to have the head welded properly.

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private

Reply to
blah blah

The oil is in the cylinder and mixed with gas. It could be rings or really bad valve stem seals. If it easy, I can pull the heads and find out. I'm quite mechanically inclined and this engine is looks easier to work on than my 3000GT/VR4 or DSM.

Reply to
Nobody U. Know

I do believe the first couple of years where only twin cam

Reply to
Jeremiah

Sorry I thought you ment it was getting in the spark plug wells and yeah just about anythings easier than the cars you mentioned. No real need to pull the head off just yet because it doesnt sound like the problem.

Check your plugs wires and coil. You may not be getting good spark.

Clean your throttle body and IAC valve. Also clean your EGR and PCV valve. The pcv is one source of oil consumption. If your rings or valve train was the cause of the oil loss it wouldnt be the cause of it running rough at idle unless it builds up a lot of carbon from it.

Reply to
blah blah

I did the wires and plugs (how I discovered the oil). I talked the guy down to $1k. After seeing the oil, I guess I was smart to talk him down.

As for the idle, it's perfect. It stutters like bad wires under practically no throttle/load. If I punch it, it is smooth. My experience with wires is they start acting up high in the RPMs and move down until they are just bad under any load.

The emmissions test was 153 PPM HC with a limit of 155 PPM (by comparison, the GT had 1 PPM with no cat and two old turbos). That means some oil getting into the combustion, either from a gasket or a crack. I was told the heads were notorious for cracking.

Reply to
Nobody U. Know

It's dual cam. Didn't know they made a single.

Reply to
Nobody U. Know

Wow. The oil indicates a bad cam cover gasket. $1K is about $900 too much.

That's not really the case. The SOHC heads were bad for a couple of years, but in general they're no better or worse than most other motors. Both engines are notorious for oil burning, though - is that possibly the cause of your high HC readings? I really don't know if that high a reading is only caused by head cracks or not. -Rick

Reply to
Rick Murphy

I cant follow this anymore, I got to make sure... Where are you seeing oil? On the plug TIPs or in the spark plug WELLs?

I can ground out wires on my 3800 and run smoothly on 3 cylinders at any rpm range. Different engines = different behaviors. Wires should be check for arcing and amount of resistance. If you have any wire that is over 15k Ohms consider replacing it.

Stop worrying about a crack! Have you cleaned out the throttle body? Have you cleaned or replaced the PCV valve? If not then do the easy things first. Oil consumption on a Saturn usually comes from PCV valve or Piston rings. I've never seen consumption from a "crack" and I've never seen twincam heads crack. Who ever feed you that info doesnt know Saturns well enough.

Reply to
blah blah

I will summarize. I bought a beater for a good price. It supposedly consumes about a quart of oil every month or so. It stutters under a light load, more pronounced when warm. It doesn't idle badly or accelerate jerky. I first suspected an ignition problem, so I changed the wires and plugs. When I pulled two of the plugs on the passenger side, they had oil on the tips and showed oil fouling. The oil was still on the plugs and smelled of gas. The doesn't noticable smoke except a puff in the morning. The coolant is foamy but doesn't appear to have oil in it. The oil doesn't appear to have coolant in it. I suspect there is a crack in the head near the cylinder crown allowing oil to get into the cylinder rather than a gasket problem.

Reply to
Nobody U. Know

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