Because a leakdown test will tell you whether the loss of compression is happening through the head or the block. That's rather the point of the test. Since adding oil to the cylinders increased compression, that suggests the loss of compression is through the rings. A leakdown test will confirm that.Ed Lijewski wrote:I found that using an engine crane to remove and reinstall the head helps in aligning it. And prevents damaging the back section of the timing belt cover.
On removal of yhe head, did you keep and reuse the alignment pins in the corners of the block?
Remove the turbo to throttle body hose and sniff for coolant in that passsge.
I can't see how a leak down test will give any more clarity on why/how coolant serms to be involved in combustion of those cylinders.
YMMV
I'm not sure how much clearer I can be. If you're not following, I'm sorry. TL;DR, nothing about this scenario suggests a head gasket problem. Everything suggests a bottom end problem.Ed Lijewski wrote:Your repeated advocacy for a leak down test doesn't answer the question: How a leak down test will give any more clarity on why/how coolant seems to be involved in combustion in a couple of those cylinders. His engibe could run with those compression numbers. If it wasn't choking on coolant and maybe oil.
YMMV
diozqwin wrote:Lol too many times in the past I've written something that length, with a response "yeah i didn't read that, too long"
Tl:dr -- see compression test results
Collected a bit of data, things are in motion now again to pull the head and do it again, and all things considered - it's about all I can do at this stage aside from a whole rebuild (would much prefer to do that ~2 years down the line). I went to see my local merkur master jimmy, he agrees and thinks the gasket isn't sealing. I did a few things wrong (didn't set the head down very even, used a metal gasket scraper to scrape off the blue gunk, took me a couple attempts to line it up, event still maybe block not clean enough)
Previously it did have white smoke on startup, which is gone since the head came back. The car will run, kinda has very low power, sometimes goes into a chugging train funk at ~500 rpms until it dies or pulls itself out into an either rumbly 1000 or decently smooth 1000 rpm. It'll die just trying to move it around the driveway (unless I keep it at 3000 rpms, even still before it used to have enough to torque for me to inch off the cluth and it would scoot a little)
COMPRESSION TEST RESULTS
First compression tests (dry, warmed up engine)
1: ~80 PSI
2: ~95 PSI
3: ~ 95 PSI
4: ~95 PSI
Second compression tests (dry, cold engine, max #'s)
1: ~90
2: ~110
3: ~105
4: ~110
(this was the only time I had someone help me by cranking it as i watched the gauge, each crank seemed to pump up the gauge about 15 psi rather consistently)
After this, I ran the engine until the smoke came and took notes,
Hard to start, ran steady for 5 minutes
Change of tone 5:30, sounds like a gurgling toilet from oil cap hole
8 less noise -- timing starts to go kinda crazy
9:40 starts to smell
11 at 2000 RPM on its own
11:30 revved down
12:30 smoke from tailpipe, revs back up, shut off car.
Days later, I rented the coolant pressure tester, pumped to 16 psi, only detectable leak was front radiator hose - tightened it
Changed a couple sketchy vacuum lines, (couldn't get pressure to build from pumping a vacuum tester tool). Turned on the engine with the vacuum tester connected into the lines, hovering crazily (not calibrated gauge?) around 12-16.
Car took quite a lot of cranks to start that time, first started at 500 rpms chugging but not dieing
Shut it off started at 1000 after a couple tries
Coolant pressure gauge didn't go up at all while the car ran, i pumped it to 16, didn't notice a change like coolant was leaking any more than before, (engine was basically "cold" though)
Oil puddled on camshaft pulley, as if it came through the middle seal.
MORE COMPRESSION TESTS (the next day)
Spark plugs pulled
Cyl 1: Smells like oil / carbon
Cyl 2: Mostly oil smell
Cyl 3: Oil, subtle coolant smell
Cyl 4: Smells like sooty coolant
Compression test (dry, cold, 10 cranks)
Cyl 1: ~85
Cyl 2: ~100
Cyl 3: ~90
Cyl 4: ~100
Compression test (wet, cold, 10 cranks)
Cyl 1: ~95
Cyl 2: ~110
Cyl 3: ~120
Cyl 4: ~120
Compression test (wet, cold, 12 cranks -- added more oil to cyl 1)
Cyl 1: ~110-115
Cyl 2: ~120
Cyl 3: ~125
Cyl 4: ~120
Compression test ( wet, cold, 20 cranks)
Cyl 1: ~120
Cyl 2: ~120
Cyl 3: ~125
Cyl 4: ~120
So I don't really know what kind of sign to make of the wet compression results, but the plan is to do the head again, this time with a Felpro 1035 gasket, cleaning the block even more, checking it with a metal ruler and a flash light, then copper gasket maker on both sides of the gasket and setting down the head as evenly as possible with a cherry picker.
That's why I'd re do the head/gasket R&R. It ran before; it's got issues now. EOS.In any case, the engine used to run before all of this, and it seems like its choking and clearly burning coolant in one or more cylinders. I'm hoping with a re-done head gasket, it will become drive-able, and I'll have time to find a second block and get it rebuilt.
