What should I do???
Thread Starter
Intermediate
Joined: May 2006
Posts: 25
Likes: 0
From: Laveen AZ
What should I do???
I took my 1988 into the dealership to have them look for an oil leak. they are telling me that 2 of the cylinders are below specs for the pressure test. They say 150psi is what it should be but one cylinder is in the 70s and the other is in the 80s. they are telling me that the leaks are from the valve covers and the lower plenum and don't recomend putting any more $$ into the motor. A shop here in town quoted me $4100.00 and change to replace the motor with a L98 rebuilt to Corvette specs. Chevy doesn't make the L98 anymore. A crate motor would be a 383. What does that mean as far as conversion? i'm really not sure what to do at this point. should i replace the motor or just fix the leaks? if I replace the motor how should I go about doing that?
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
I'm curious what step of the "look for leaks" procedure includes a cylinder compression test. If you trust the dealer, those numbers are cause for concern. How does it run? What do you use the car for? My advice is, 1.) buy yourself a FSM (Factory Service Manual), and 2.) stay away from dealers. If the engine runs acceptably well, YOU can replace the gaskets and fix the leaks for a reasonable amount of money. YOU can do a compression check to verify the dealer's information. Depending on what you want, you can buy engines that cost less than the 383. You can also buy more power, if that is what you want and is within your budget. As a rule of thumb, you can save half, to two thirds, by doing it yourself. Some jobs are all labor. You save the whole thing.
RACE ON!!!
RACE ON!!!
Race Director
Joined: Sep 2003
Posts: 16,835
Likes: 337
From: Database Error Indiana
If nothing else, get a 2nd garage to look at it. If it needs a fresh motor, take some time to decide what you really want. Stock, you can get from Scoggin & Dickey. If you want more, then the choices are only limmited by your $$$$$. Hang around here and do some studying.
[disclaimer: remember, this is the internet, dont believe everything you read]
[disclaimer: remember, this is the internet, dont believe everything you read]
Thread Starter
Intermediate
Joined: May 2006
Posts: 25
Likes: 0
From: Laveen AZ
The dealership shop says the compression is as follows...
1-80psi, 2-100psi, 3-100psi, 4-110psi, 5-91psi, 6-95psi, 7-95psi, 8-75psi.
the car runs strong. It certainly doesn't feel like a car with a bad motor. I took it home and put a 'JET" chip in it that had arrived today just for the fun of it. Turns out the ECM already had a "MOATES" chip in it. Whoever programed it probably didn't know what they were doing because it runs much better now. I'm thinking I should have someone re do the compression check to verify the dealership's story because I have my doubts. I'm not sure how to do a check myself though....
maybe I just need to get the oil leaks fixed by some other shop that won't try to put the screws to me.
1-80psi, 2-100psi, 3-100psi, 4-110psi, 5-91psi, 6-95psi, 7-95psi, 8-75psi.
the car runs strong. It certainly doesn't feel like a car with a bad motor. I took it home and put a 'JET" chip in it that had arrived today just for the fun of it. Turns out the ECM already had a "MOATES" chip in it. Whoever programed it probably didn't know what they were doing because it runs much better now. I'm thinking I should have someone re do the compression check to verify the dealership's story because I have my doubts. I'm not sure how to do a check myself though....
maybe I just need to get the oil leaks fixed by some other shop that won't try to put the screws to me.
Burning Brakes
Joined: Nov 2005
Posts: 848
Likes: 1
From: 1992 LT1 6 speed Cayman Islands
Originally Posted by Instructor 357
The dealership shop says the compression is as follows...
1-80psi, 2-100psi, 3-100psi, 4-110psi, 5-91psi, 6-95psi, 7-95psi, 8-75psi.
the car runs strong. It certainly doesn't feel like a car with a bad motor. I took it home and put a 'JET" chip in it that had arrived today just for the fun of it. Turns out the ECM already had a "MOATES" chip in it. Whoever programed it probably didn't know what they were doing because it runs much better now. I'm thinking I should have someone re do the compression check to verify the dealership's story because I have my doubts. I'm not sure how to do a check myself though....
maybe I just need to get the oil leaks fixed by some other shop that won't try to put the screws to me.
1-80psi, 2-100psi, 3-100psi, 4-110psi, 5-91psi, 6-95psi, 7-95psi, 8-75psi.
the car runs strong. It certainly doesn't feel like a car with a bad motor. I took it home and put a 'JET" chip in it that had arrived today just for the fun of it. Turns out the ECM already had a "MOATES" chip in it. Whoever programed it probably didn't know what they were doing because it runs much better now. I'm thinking I should have someone re do the compression check to verify the dealership's story because I have my doubts. I'm not sure how to do a check myself though....
maybe I just need to get the oil leaks fixed by some other shop that won't try to put the screws to me.
With those numbers your motor should shake and be down on power. The numbers themselves indicate two bad head gaskets but I would chaek the compression myself to make sure they are reporting it correctly. If the car runs fine then replace the valve cover caskets.
If their numbers are correct you could replace the head gaskets yourself with the engine in the car and witgh new intake gaskets and new valvecover gaskets you should also catch the oil leak.
I think the Dealer is trying to talk you into more cost than is necessary, so doublecheck everything they told you.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by Instructor 357
The dealership shop says the compression is as follows...
1-80psi, 2-100psi, 3-100psi, 4-110psi, 5-91psi, 6-95psi, 7-95psi, 8-75psi.
1-80psi, 2-100psi, 3-100psi, 4-110psi, 5-91psi, 6-95psi, 7-95psi, 8-75psi.
Originally Posted by Instructor 357
they are telling me that 2 of the cylinders are below specs for the pressure test. They say 150psi is what it should be but one cylinder is in the 70s and the other is in the 80s.
RACE ON!!!
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Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
I'd have someone redo the test, is it running hot and are there any signs of coolant in the oil? hard for me to believe the numbers are that low if it's running good, both my 350s in my boat have 1600 hours on them and have considerably higher compression (150 range) than that.
What I find really strange here is the location of the 2 cylinders 1 & 8...opposite ends and banks?
How many miles are on your engine?
What I find really strange here is the location of the 2 cylinders 1 & 8...opposite ends and banks?
How many miles are on your engine?
Last edited by rick lambert; Oct 7, 2006 at 02:37 PM.
Thread Starter
Intermediate
Joined: May 2006
Posts: 25
Likes: 0
From: Laveen AZ
I took the car to another mechanic. He said I have "blow by" because my rings are shot. He says if I fix the leaks I'm going to get them back because the oil pressure will soon get the oil past the new gaskets (lower plenum & valve covers) anyway, so don't waste the money. He says get a new engine. He doesn't do engine replacements or re builds so I don't see any reason he would lie.
If I get a crate motor it would have to be a 383. I would like to know how that fits in the car and what needs to be modified to make it work. A remanufactured L98 would seem to be less trouble???
If I get a crate motor it would have to be a 383. I would like to know how that fits in the car and what needs to be modified to make it work. A remanufactured L98 would seem to be less trouble???
Drifting
Joined: Mar 2004
Posts: 1,522
Likes: 0
There are alot of choices out there, it all depends on your goals, what you want out of the car, and your budget.
There are alot of companies that would happily make you a motor to your specs. The only thing that would have to be replaced specifically with a 383 are the fuel injectors, and a good dyno tune. It can start to add up if you want to do new heads, new intake, and a little bit of maintaince along the way, "since your in there".
There are alot of companies that would happily make you a motor to your specs. The only thing that would have to be replaced specifically with a 383 are the fuel injectors, and a good dyno tune. It can start to add up if you want to do new heads, new intake, and a little bit of maintaince along the way, "since your in there".
Race Director
Joined: Dec 2002
Posts: 13,345
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
Originally Posted by Instructor 357
maybe I just need to get the oil leaks fixed by some other shop that won't try to put the screws to me.
You mean there IS such a thing???!!!! 
Originally Posted by Instructor 357
If I get a crate motor it would have to be a 383.
Larry
code5coupe
Last edited by rocco16; Oct 12, 2006 at 01:00 PM.
