My horror story with the 3.1L engine

[Rolm]

I got a great deal on a 97 GT with leather, 3-spoke original rims with almost new tires. The only problem was with the engine there was a miss it started great but there was this miss is if one of the spark plug wires were off.

I proceed to do a compression test on all the cylinders and as I suspected I found 1-cylinder with a 30-psi and all the rest had 150-psi. I thought great there must be a burnt valve. It took me 6 hours to remove the front head off the engine. In inspecting the head everything looked perfect. I then pored transmission fluid in the bad cylinder and in the other 2-good cylinders I left the fluid in the cylinders overnight and in the morning I noticed that in the bad cylinder the fluid had run out and in the good cylinders the fluid was all there.

I figure great I will pull the oil pan off and remove the bad piston and replace the rings and everything would be ok, till I looked under the engine and what a horror story it was almost impossible to remove the oil pan in these dam engines. I think there were like 20-30 items to be removed. I decided I could not do that job. I put the engine back together with new gaskets and I had a small hope that the transmission fluid may have release any sticky rings and with the new gaskets that I may have fixed the problem. I re-tested the compression on the bad cylinder and it was just as bad 30-psi. What a disappointment. I guess I will sell the GT as is. Later

[pcprophet]

well if the fluid has drained away from the bad cylinder then it tells you that its not a bad valve but either the compressions ring or oil rings are worn out and might need replacement. check the dimesions of the cylinder wall with a telescopic gage and measure with a micrometer and test for out of round etc. dont know the exact specs though. you might be able to get away with a oversized piston the compensate for the bigger cylinder.

if that isnt it, then check to see if the oil is a milky substance, if so then you will have a cracked engine block and coolant has mixed with the oil and will need a new one, you can test with a magnet and some iron fillings the iron fillings will enter the crack and fill it up. need a good eye since that crack wont be very noticeable.

dont know what else to add but thats what i could come up with and hopefully give you some ideas and hopefully others with help yah out.

[kamoguy]

If all else fails, a new 3400 would bolt up. Or a used 3400. And rebuilt 3100s are about $600 any more. The new 3400 would be double that, about $1200-$1400.

I got a decent deal on a 97 too this summer, just no leather seats. It just rolled over 110,000 miles, so I'm saving up for the fresh engine and treating it as something I will inevitably have to swap.

[Rolm]

Here in Canada they want $1800.00 ( $1620 US) for a rebuilt 3100. As I said it was to bad I could not remove the oil pan that would have been the cheapest solution.