Burnt valve!

[sdwhite]

Hello all-

 

'95 Cutlass Supreme, 3.1. 200k. Some of you may remember my ongoing saga with this car. Dies at idle, no power, runs extremely rough. Did the regular stuff: plugs, wires, TB clean, lower intake gasket, upper intake gasket. Still ran like crap.

 

So, I broke down and brought it into a shop. The mechanic was a genius...by listening to it trying to start he heard *one* cylinder had no compression. The starter would speed up for the 1/6 of the time it was pushing against nothing. Clever guy.

 

Anyway, he did a compression test on all cylinders and discovered that #5 had no compression with and without oil (naturally, this is the rear head). Head gaskets have been replaced so he belives it's a burnt valve. They want in the neighborhood of $1200-1400 to do the job. Apparently the "no power" symptom is a result of a bad vehicle speed sensor f'ing up the tranny.

 

My question is: do you have to do a complete valve job on both heads or can you just replace the one valve? Keep in mind it's a $400 car with 200k on the ticker.

 

Since I just replaced the upper and lower intake gaskets, can I re-use them? Literally, they have about 10 miles on them.

 

Has anyone tackled this kind of project before? Any suggestions? Is it really worth it?

 

Actually...I wonder if a new head from a junk yard would be cheaper than paying someone to do the valves. Is this an option?

 

Everybody's been a great help in this project...thanks for all the info!

[Guest TurboSedan]

My question is: do you have to do a complete valve job on both heads or can you just replace the one valve? Keep in mind it's a $400 car with 200k on the ticker.

 

you can easily pull a valve out with a cheap valve spring compressor and replace the one valve. well....on a 3.1 MPFI anyway. i'm not sure about the 3100. it takes me less than 1 minute to pull a valve and put it back in. just gotta make sure the valve keepers don't go flying across the garage

 

intake gaskets aren't reuseable.

[Dan94Z34]

i;ve actually done that once, putting permance springs on my 350 when I had it. The garage walls were sheet rocked, and the spring went into the wall. 3.1/2.8 are easy to take apart and due head jobs on them. Even if the head is fucked. You can proabably get a good used one at the bone yard cheep.

[Pabz]

I ran my engine after replacing LIM & Upper, tore it apart again to replace a lifter and used the same gaskets.

 

IMHO if you can get a head from a junker it would be easier/cheaper. Might as well do the headgaskets, dont forget to get exhaust gaskets too!!!

[gp90se]

junkyard head off a low milage car, have it checked to make sure it isnt warpped by a machine shop and throw the sob on the car.

[Brian P]

junkyard head off a low milage car, have it checked to make sure it isnt warpped by a machine shop and throw the sob on the car.

 

^ what he said