brianp007438
Recruit
- Joined
- Apr 9, 2009
- Messages
- 2
Hello,
I have a 1999 Volvo 4.3GL in my 18.5' Regal. Recently it's been missing/stumbling at high RPM (4200-4600) so I took it to my mechanic. He said he did compression and leak down tests on the motor and told me there was a bad valve somewhere. I told him I'd take it from there and I did.
I did another leak down test (he left me no info) and found the #1 cylinder was leaking about 80% and the other five were holding steady around 2%-8%. I wanted to verify the head was the problem as the mechanic had stated. I charged everything up and felt the carburetor for air - nothing. Then I removed the exhaust elbow, still no air leaking. But at 100psi input, the cylinder wouldn't hold more than 20psi! Now I'm getting real worried, thinking about broken rings and pricing remanufactured engines online. I pulled the head today, praying the whole time for an obviously blown head gasket, a burnt valve, even a crack in the head would've been OK at this point. Problem is, there is nothing visually wrong with the cylinder head, block, piston, head gasket, anything! I don't have a straight-edge but I would be shocked to find an iron head warped that didn't take the gasket with it. I don't know where to go from here except the machine shop.
Also, the motor ran strong and very smooth before all this, only the "missing" at the top end of the RPM band. It wasn't overheating and absolutely never smoked, which is why I still have my fingers crossed for the rings. It did seem to run a little warmer though, around 165-175. That made me suspect low compression/head gasket. It has a 160deg thermostat in it, but it used to run around 140 degrees and even colder at high RPM. Of course I take my dashboard temp gauge with a grain of salt too.
Any information at all would really help - anyone had anything like this before? Thank you in advance,
Brian
I have a 1999 Volvo 4.3GL in my 18.5' Regal. Recently it's been missing/stumbling at high RPM (4200-4600) so I took it to my mechanic. He said he did compression and leak down tests on the motor and told me there was a bad valve somewhere. I told him I'd take it from there and I did.
I did another leak down test (he left me no info) and found the #1 cylinder was leaking about 80% and the other five were holding steady around 2%-8%. I wanted to verify the head was the problem as the mechanic had stated. I charged everything up and felt the carburetor for air - nothing. Then I removed the exhaust elbow, still no air leaking. But at 100psi input, the cylinder wouldn't hold more than 20psi! Now I'm getting real worried, thinking about broken rings and pricing remanufactured engines online. I pulled the head today, praying the whole time for an obviously blown head gasket, a burnt valve, even a crack in the head would've been OK at this point. Problem is, there is nothing visually wrong with the cylinder head, block, piston, head gasket, anything! I don't have a straight-edge but I would be shocked to find an iron head warped that didn't take the gasket with it. I don't know where to go from here except the machine shop.
Also, the motor ran strong and very smooth before all this, only the "missing" at the top end of the RPM band. It wasn't overheating and absolutely never smoked, which is why I still have my fingers crossed for the rings. It did seem to run a little warmer though, around 165-175. That made me suspect low compression/head gasket. It has a 160deg thermostat in it, but it used to run around 140 degrees and even colder at high RPM. Of course I take my dashboard temp gauge with a grain of salt too.
Any information at all would really help - anyone had anything like this before? Thank you in advance,
Brian