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So whats wrong with this engine ? HELP !


Chuck T.

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Help me out experts.

I have a 1988 924S with major engine problems what do yall think would fix it?

 

As I was driving down the interstate it started pouring out white and blue smoke from the tail pipe. I pulled over and it had lots of water in the oil (milkshake). I drove it easy the rest of the way to the roll cage shop and it did not smoke. After the cage was done. I towed it home and started taking it apart. There was lots of milkshake in the air box (under the air filter) and all in the intake, it seemed to be coming from the oil separator. I did a compression check and all 4 were 130-135 psi. Engine seemed to run fine. The engine had a new head gasket right before I bought it (head was shaved). I took it all apart tonight and the head gasket looked fine the oil cooler o rings looked pretty bad. head looks fine and the cylinders looked fine ....

 

There was a little bit of oil in the water when I got the car but no worse since this happened.

I have an engine coming from Frank (socal) but it might not be here till Tuesday... Our first race is next weekend and my car is needed to make 5 entries. So should I put a new head gasket and oil cooler o rings in it ? Do I need to have the head shaved agian ? Or should I remove the engine and hope the one from Frank gets here in time so I can work on it 48 hours straight before race weekend? Also the head gasket I removed from the car had "Turbo" on it ... Is that the right head gasket ?

 

Thanks for the help.

Chuck

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Chuck,

 

The engine coming to you has a rebuilt head (valve job, new seals, guides checked/replaced, resurfaced for flat surface but not shaved any more than necessary, pressure tested, bead blasted, etc). The head gasket for turbo and n/a are the same and the engine is coming to you with a new head gasket, cam tower gasket, new low temp thermostat, and the rest of the gaskets in the original package so you can install it when you swap your intake/exhaust etc. New timing belt is installed and while I had the cam tower out, it looks like the lifters were replaced before and look very new.

 

Wait for the motor because I would not throw a motor together to get on the track. It will only frustrate you when it breaks down and take the fun out of being out there. The motor is in the 924S passenger side already just waiting for the shipper. I will call them tomorrow and if it will help, I can even drive the car to their station locally.

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Thanks Frank !

I trust you 100% I just don't know about the shipping company ... If they give me the run around and don't get the engine here on time I will be up the creek. My guys are depending on me to be car #5... Engine sounds great !

 

Chuck

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There was lots of milkshake in the air box (under the air filter) and all in the intake, it seemed to be coming from the oil separator. I did a compression check and all 4 were 130-135 psi. Engine seemed to run fine. The engine had a new head gasket right before I bought it (head was shaved). I took it all apart tonight and the head gasket looked fine the oil cooler o rings looked pretty bad. head looks fine and the cylinders looked fine ....

 

There was a little bit of oil in the water when I got the car but no worse since this happened.

 

Couple things.

 

Oil cooler seals are notrious for leaking and causing mixing. Replace the seals and 90% of the mixing goes away. A few cases mixing can be due to a seal in the head gasket. That is most common with an old head gasket. So cooler seals should fix it.

 

Now shaved head on an 88 motor could be a problem. Max compression limit in the class is 10.5:1. 88 motors with small dish pistons start at 10.2:1. So anything over a minor shave could put you over 10.5

 

So if you run that 88 with shaved head you could be a 10:7 which is not legal and would need at least to run race gas to prevent it from deotonating on track. Put the same head on 9.5:1 engine and you would be fine.

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Joe how are you going to verify if he is at 10.7 or at 10.5? I'd really like to know. That's why the rules were better when we were at 11.0:1. Since there is no easy way to check CR.

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Joe how are you going to verify if he is at 10.7 or at 10.5? I'd really like to know. That's why the rules were better when we were at 11.0:1. Since there is no easy way to check CR.

 

Measure the deck height on the head. That is easy to do with out removing anything and it has a factory spec. I will need to do some math to convert the mm of shave to actual CR increase.

 

Pretty easy really.

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looking at the head I would guess it was shaved just enough to make it flat not a shave like to raise compression ... The compression tester only made 130-135 psi . Is that high ? Weston"s car made 160 psi (1983).

 

chuck

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looking at the head I would guess it was shaved just enough to make it flat not a shave like to raise compression ... The compression tester only made 130-135 psi . Is that high ? Weston"s car made 160 psi (1983).

 

chuck

 

That difference is hot vs cold.

 

Shaving to make flat only removes a small bit of metal maybe .005. Shave to increse compression is quite a bit more close .050 to .060. My guess is you are over 10.2:1, but probably well under 10.5:1. The reason we allow 10:5 is for your case where and 88 motor need to have the head shaved for flatness rather than trying increase compression.

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