1995 diesel compression

[vic]

What compression should the cylinders have? Dealer tells me I need 380lbs He said that is why it is hard starting. Please advise
Thanks Vic.

[damork]

I don't have a service manual near by, but I disagree that 380 psi is too low, or the reason you have hard starting. I had 400 psi across the board at 76k miles on my 6.5 and I had a 6.2 that was lower than what you have at 113k miles. When the 6.2 went over 200k miles, I still got it started below zero without a lot of pain. The key in getting the 6.2 to start good was advancing the timing to clear up white smoke at the start. It never had new glow plugs up to the time I got rid of it as I knew the previous owner too.

Look at timing, injector condition, glow plug relay, glow plugs, water temp sensor, fuel supply to your injector pump, injector pump condition, and fuel quality. There's other things to look at too, but just some ideas to start with.

[cruzer]

According to The Diesel Depot in the advertiser section, it states they sell used engines and the min compression on them is 350psi. Find another dealer. If you give the symptoms, the yr, make, model, miles and anything else that may be enlighten the members, you will probably find the solution here. You can look at past posts also using the "search" function at the top of the page.

[vic]

thanks for the response on my 95 diesel. It has 85,000 miles. It is very hard starting the first time even if the temp is 50 degrees, that is why I took it to the dealer. He first changed injector pump which he said would be covered by GM. Now I get a call saying it still doesn't start very good and he thinks it is a compression problem. He said the minimium is 380 lbs.
The motorhome has been burning a quart of oil every 400/500 miles.
thanks Vic

[cruzer]

That's too much oil IMO. In your other post you said something like a FEW clydrs had 300psi. They should as a rule be within 10% of each other on avg. If you have some cyldrs at 300psi and others at 380psi then there has to be some reason why there is such a difference. I think you need more diagnoses if this is the case. You also need to find out which cyldr has what.