Sean
07-05-2017, 07:23 PM
Anyways, I won't get into much detail right now - will add more later. I am new to ZHP Mafia, but not new to BMWs. Have a 95 M3 and 88 325 (stroker in 07) that I have had for as long as I can remember. I digress though.
I recently dealt with a hole in a valve on my wagon's 95k young engine (no clue why): http://forum.e46fanatics.com/showthread.php?t=1124176
In order to make the most of a shitty situation, I used that as an excuse to source a ZHP engine and a 6spd trans. I was VERY careful. Drove to Chicago, brought a bunch of tools with me: air compressor, leakdown tester, camera/scope. I inspected my prospected ZHP engine with a fine tooth comb. 160k miles (more than I'd like), but the leakdown passed VERY strongly. Something like 2% loss on each cylinder. Engine seemed well cared for (very clean), no cracked boot, etc. So, I bit the bullet.
Fast forward to getting home, I decided to hook up a battery and "bench" compression test it. In the matter of weeks, I lost compression on cylinders 1, 3 and 5 (ranged from 40-95). This had me at a complete loss. Cylinders 2, 4 and 5 were at 193, 190 and 200 respectively. Did leakdown, found exhaust valves on "bad" cylinders leaking for some reason.
I let it sit as I dealt with other things. The other night I took the valve cover off to ensure no issues. Nothing prevalent. Did another leak down. Now ALL cylinders are leaking during my leakdown testing. W T F?
My only guess is the valves are not closing all the way? Maybe oil in the hydraulic lifters or something?
So, I begin dismantling the head. Got my exhaust cam off tonight and journals 3-6 all have some nasty marks on them! One of the advantages of the ZHP engine is the cam. But, after seeing these journals, I'm really concerned. Is there anything I can do to fix them?
Will post pictures tomorrow.
Discussion commence! ;)
-Sean
I recently dealt with a hole in a valve on my wagon's 95k young engine (no clue why): http://forum.e46fanatics.com/showthread.php?t=1124176
In order to make the most of a shitty situation, I used that as an excuse to source a ZHP engine and a 6spd trans. I was VERY careful. Drove to Chicago, brought a bunch of tools with me: air compressor, leakdown tester, camera/scope. I inspected my prospected ZHP engine with a fine tooth comb. 160k miles (more than I'd like), but the leakdown passed VERY strongly. Something like 2% loss on each cylinder. Engine seemed well cared for (very clean), no cracked boot, etc. So, I bit the bullet.
Fast forward to getting home, I decided to hook up a battery and "bench" compression test it. In the matter of weeks, I lost compression on cylinders 1, 3 and 5 (ranged from 40-95). This had me at a complete loss. Cylinders 2, 4 and 5 were at 193, 190 and 200 respectively. Did leakdown, found exhaust valves on "bad" cylinders leaking for some reason.
I let it sit as I dealt with other things. The other night I took the valve cover off to ensure no issues. Nothing prevalent. Did another leak down. Now ALL cylinders are leaking during my leakdown testing. W T F?
My only guess is the valves are not closing all the way? Maybe oil in the hydraulic lifters or something?
So, I begin dismantling the head. Got my exhaust cam off tonight and journals 3-6 all have some nasty marks on them! One of the advantages of the ZHP engine is the cam. But, after seeing these journals, I'm really concerned. Is there anything I can do to fix them?
Will post pictures tomorrow.
Discussion commence! ;)
-Sean