I am considering buying a 98 gsr with 106k miles and one of the cylinders has low compression. My guess is a chipped exhaust valve. Should I replace just the broken valve, all the exhaust valves, or all the valves?

I am not looking to do a lot to engine down the line and just want something reliable. Should I replace with oem valves or after market. The after market options seem to be cheaper. I saw the Blox valves online for around 120 for 8 valves. Does anyone have an opinion on brand of valve?

I was also planning on replacing the timing belt, water pump etc.. Is there anything else that should be replaced while the head is off?

I am trying to get an estimate of what this would cost in advance and what is the best router. Thank you in advance for your opinions.

 

Have you adjusted the valves to make sure a bent or chipped valve is the issue? Did you mis-shift and cause a mechanical over-rev? What CEL's did the engine ECU throw? Have you considered a leak-down test?

I would wait until I pulled the head (if you need to) to determine the best course of action.

 

I don't own the car so I don't know if it was over revved. The current owner says it was never over revved FWIW. It throws code 73 misfire cyl. 3 when it is at idle for a while but not when driving. I haven't done a leak down test and it looks like I will have to decide whether or not to buy it without that information.

 

Honestly, adjust the valves and redo the compression test. If the compression is still low, the head has to come off. The money shift (3rd redline to 2nd) is the leading cause of bent exhaust valves.

 

So I did the compression check (aparker is my brother) and the results were

225, 225, 175, 225 for cylinders 1, 2, 3,4 respectively. Do you think that there would be a decrease of 50 psi in one cylinder for just out of adjustment valves???

 

If you want to find out the actual problem, do a leak down test, a compression test will show that theres a problem but not what the problem is

a leak down test can tell you if its a head gasket, intake or exhaust valves, rings or cylinder

 

Yes. A valve that is adjusted too tight will not fully close. If you check the adjustment and it is fine, then you have a leaking valve.

 

I decided to buy the car. The valves didn't require to much adjusting and the compression was still low. The head is now off the car and off to a machine shop tomorrow. I think I will have it worked on at lynns machining. Does anyone have an opinion on this shop or any others in the South Bay Area, CA. Here are some pics of the car and engine.

 

not bad good luck how much?

 

$2800, I think it is a good price. We will see how much the repairs come out to.