I hope someone can help me here, because I am at a complete loss.
I finally decided I've had enough with the water leaks around the heads and decided to go ahead and replace both head gaskets.
Before I proceeded, I checked the timing alignment and noted that the P mark on the crankshaft was perfectly aligned with the pointer and both crankshaft marks were also aligned perfectly.
I removed and cleaned the base of the heads and the block as well, being careful to provide a clean mating surface for the new head gaskets.
The old mulitpiece gaskets were replaced by the single one piece gasket. I was careful to remove liner sealing rings.
So I button it all down, torque the head according to spec. and replace the timing belt. Everthing perfectly aligned as before. Do a compression test and WTH??? 35 psi on cylinder 1 and 2, 120 psi on cylinder 4 60 psi on 5. I stopped there. Where did I go wrong?? Before the replacement all cylinders were between 175 - 190. My first reaction was "You dumbass you messed up the timing", but I rechecked and everything lines up.
The dealer who sold me the head gaskets assured me it is the correct type for the 2.5 V6. Have I missed something?
Any help, ideas or other corresponding idiocy checks would be greatly appreciated. I have no ideal what I have done wrong.
Marco
Head Gasket Replacement Issues!!!
Marco
1985 Alfa 90
1985 Alfa 90
Marco...Make sure they were 2.5l gaskets..
No dont laugh,but I have done the following over the years...
Pinched the efi harness between head and block at the rear...
Pinched an injector plug and harness between head and block.The plug was in the chamber/cylinder.
Check it out,its so easy when your doing it alone...
No dont laugh,but I have done the following over the years...
Pinched the efi harness between head and block at the rear...
Pinched an injector plug and harness between head and block.The plug was in the chamber/cylinder.
Check it out,its so easy when your doing it alone...
Hi Barry,
Yeah,
indeed I though this might be the case as well and I might have expected this for the second head that goes on as it is easier to have this happen, however I was very careful and checking with a light and mirror revealed this not to be the case as the heads look well seated all around.
I could imagine getting one head wrong if I had a gasket seating problem, but both heads??? Not out of the realm of possibility but certainly enough to make me want to put my wrenches down for a while and sit on a chair facing the corner.
Marco
Yeah,
indeed I though this might be the case as well and I might have expected this for the second head that goes on as it is easier to have this happen, however I was very careful and checking with a light and mirror revealed this not to be the case as the heads look well seated all around.
I could imagine getting one head wrong if I had a gasket seating problem, but both heads??? Not out of the realm of possibility but certainly enough to make me want to put my wrenches down for a while and sit on a chair facing the corner.
Marco
Marco
1985 Alfa 90
1985 Alfa 90
Hi Barry,
Mystery solved.
I think this is one for the books.
I called Luigi Amori from Italservice in South Australia and after going through the usual problem checking he asked if I rebuild the heads. I responded that the heads had not been touched. He then suggested that what possibly happened is that dirt or carbon from the exhaust port may have found it's way to the valve seats during handling of the head. As I did not clean the valve seats, I thought this might be plausable.
He suggested to take all the plugs out, fully charge the battery and spin the engine for 10 -15 seconds to try to dislodge anything around the seats. I did this and then did a compression recheck and all values jumped to 120 - 130 psi. Which was still somewhat low. I realized also that when I put the heads back on I cleans the cylinder walls thoroughly, to remove the water and oil that had fallen in during the head removal, so they were bare of oil. I dripped some oil through the plug hole did a compression retest and voila 210 psi!!
Slapped her back together, cranked her over a few times and fired right up. Didn't even have to reset the timing.
I think the moral of the story here is this:
1. Make sure the valve seats are clean and the valves are seating properly even if you are doing a simple head gasket change.
2. squirt a bit of oil on the piston edges before reassembling the heads.
I'm glad this one had a happy ending. I was getting that cold shiver down the back of my spine at the thought of having to take the heads off again.
Cheers,
Marco
Mystery solved.
I think this is one for the books.
I called Luigi Amori from Italservice in South Australia and after going through the usual problem checking he asked if I rebuild the heads. I responded that the heads had not been touched. He then suggested that what possibly happened is that dirt or carbon from the exhaust port may have found it's way to the valve seats during handling of the head. As I did not clean the valve seats, I thought this might be plausable.
He suggested to take all the plugs out, fully charge the battery and spin the engine for 10 -15 seconds to try to dislodge anything around the seats. I did this and then did a compression recheck and all values jumped to 120 - 130 psi. Which was still somewhat low. I realized also that when I put the heads back on I cleans the cylinder walls thoroughly, to remove the water and oil that had fallen in during the head removal, so they were bare of oil. I dripped some oil through the plug hole did a compression retest and voila 210 psi!!
Slapped her back together, cranked her over a few times and fired right up. Didn't even have to reset the timing.
I think the moral of the story here is this:
1. Make sure the valve seats are clean and the valves are seating properly even if you are doing a simple head gasket change.
2. squirt a bit of oil on the piston edges before reassembling the heads.
I'm glad this one had a happy ending. I was getting that cold shiver down the back of my spine at the thought of having to take the heads off again.
Cheers,
Marco
Marco
1985 Alfa 90
1985 Alfa 90
