Compression too high

[ludedude]

So I go the engine back together Did a leak down test and had a small leak around the intake....lost 2 psi in 11 minutes. Fixed that...held 10psi for 10+ minutes :wink:

Installed the engine, and went to do a compression test....starter's not engaging..I must have put something together wrong in there...so out it has to come again....it spins fast, even put a booster/charger on it, no difference....SUCKS!! I was going to do a compression test on the bench, but figured you need the pipe on to get a accurate reading as the pipe actually pushes some air back in does it not?


Anyhow..I pulled it with the pull rope and checked compression....190 psi!! :shock: I was hoping for 160-170...170 is the LIMIT is it not for pump fuel?

Can I put a inner layer (silver one) of a head gasket in as an extra layer and try that? Will it seal properly? What else if not that? I have another head, but it's stock and will likely be in the 140-150 range...I may try that one to see where it's at....

[PilotSniper]

So I go the engine back together Did a leak down test and had a small leak around the intake....lost 2 psi in 11 minutes. Fixed that...held 10psi for 10+ minutes :wink:

Installed the engine, and went to do a compression test....starter's not engaging..I must have put something together wrong in there...so out it has to come again....it spins fast, even put a booster/charger on it, no difference....SUCKS!! I was going to do a compression test on the bench, but figured you need the pipe on to get a accurate reading as the pipe actually pushes some air back in does it not?


Anyhow..I pulled it with the pull rope and checked compression....190 psi!! :shock: I was hoping for 160-170...170 is the LIMIT is it not for pump fuel?

Can I put a inner layer (silver one) of a head gasket in as an extra layer and try that? Will it seal properly? What else if not that? I have another head, but it's stock and will likely be in the 140-150 range...I may try that one to see where it's at....

Wow, bud! Was the head just cut down too much? I remember Moskito telling me that 195psi (the reading on my original head) needed to be run with racing fuel or I would cause a meltdown. That's what happened before I found out what head I actually had, so I believe he was correct. Try the stocker head and see what reading you get. If it's the 140-150psi range, then I believe the head was just cut down too much. Is there anything else that can cause the compression to read this high? Can you test the gauge on the other Pilot you have? Just rambling out loud...

[ludedude]

Yeah I have a few things to try...just need time!!!!

I put the cylinder that was ported by Rick Kirmil (MacDizzy)....OK the whole story.....

I bought a used bottom FROM Nick, I sent it to Rick for him to rebuild the bottom end, and put a new top end on after performing his magic....tirns out the bottom end leaked and had sustained damage when it blew FROM the previous owner..Rick dismantled and supposedly had the bottom end repaired and re-assembled it.

When I got it, I could not get the compression readings I was supposed to get...there were low FROM day 1...in the 125 range....Rick blamed it on my compression gauge and said the engine was fine....a few months later I pressure test it and it leaks like a seave. I can't to this day believe it ran as good as it did :shock:

So this is the cylinder I put on my rebuild (original engine that came with the Pilot). But I put the PCP head on it...maybe the combination was too much...I don't know anymore which head came with the engine Rick did...my spare head the coated just now at Bore-Tech with the PCP head...or the head that's on the engine that just blew...(leaky bottom end) RIck never engraved anything on his work...I'll have to do that so I can tell them apart when they're assembled...

Got that all straight?!?! :wink: :roll: :roll:

So I'll pull the head off the blown one and compare to my spare...to figure out which is Ricks'...it;s been worked a little, but no where near that as the one FROM PCP....

And maybe try both on to see what I get for numbers FROM those 2 heads...then it's time to dismantle the blown one and see if the bottom end can be saved/repaired...

[PilotSniper]

Yeah I have a few things to try...just need time!!!!

I put the cylinder that was ported by Rick Kirmil (MacDizzy)....OK the whole story.....

I bought a used bottom FROM Nick, I sent it to Rick for him to rebuild the bottom end, and put a new top end on after performing his magic....tirns out the bottom end leaked and had sustained damage when it blew FROM the previous owner..Rick dismantled and supposedly had the bottom end repaired and re-assembled it.

When I got it, I could not get the compression readings I was supposed to get...there were low FROM day 1...in the 125 range....Rick blamed it on my compression gauge and said the engine was fine....a few months later I pressure test it and it leaks like a seave. I can't to this day believe it ran as good as it did :shock:

So this is the cylinder I put on my rebuild (original engine that came with the Pilot). But I put the PCP head on it...maybe the combination was too much...I don't know anymore which head came with the engine Rick did...my spare head the coated just now at Bore-Tech with the PCP head...or the head that's on the engine that just blew...(leaky bottom end) RIck never engraved anything on his work...I'll have to do that so I can tell them apart when they're assembled...

Got that all straight?!?! :wink: :roll: :roll:

So I'll pull the head off the blown one and compare to my spare...to figure out which is Ricks'...it;s been worked a little, but no where near that as the one FROM PCP....

And maybe try both on to see what I get for numbers FROM those 2 heads...then it's time to dismantle the blown one and see if the bottom end can be saved/repaired...

Man! What a rollercoaster ride!!! You've got some work ahead of you, eh? :shock:

Scribe the parts, as you've suggested, in ORDER to easily identify them. I agree that this will make life a little easier. After all is completed, you're going to be a triple M! (Master Mechanic Material) :lol:

I wish you the best of luck throughout the ordeal!

By the way, I know this goes without saying, but please post your findings so that I can learn some more about the wonderful world of engine rebuilding.

[ludedude]

I've been uploading my pictures as I take them in the POG gallery, and adding some comments to them as I do so...

I've written a write up of what / how I did it and what I'll do different next time...next time won't be that far away....well at least for tear down...so I'll re-write and UPDATE as I do that one before I look for a publisher :wink: