96 FJ80 died on startup. No compression in all cylinders... (1 Viewer)

[1972FJ55]

Here's the video of what mine sounded like when starting:

96 FJ80 died on startup. No compression in all cylinders...

I did have some compression in most of the cylinders but it was very low. I was frankly surprised it would actually run.

 

[terrx]

I got the 80 started and running well again. Wanted update with what I found. The short story: there was no problem. Some details below in case anyone is interested. Thanks again everyone for the input. Was much appreciated.

Took the throttle body and valve cover off. The timing chain, tensioner and slipper all looked good and timing marks were right on. Pulled the EFI fuse, and using a new (hopefully better quality) compression tester... cylinders 1-6 showed only 30-30-60-60-65-40 PSI. I bought a leak down tester, and while not exactly sure what it would show, wanted to try it anyway. Cylinders each registered 100% 'loss'. The air was coming out adjacent cylinder plug holes next to the one tested, which seemed weird. Maybe a valve issue?

After adding a little oil to each cylinder and rechecking compression, it improved: 100-60-70-85-115-70. Then a bit more cranking and retesting, it improved again: 125-80-75-80-150-60. At this point I figured there was enough compression to start, and was probably the problem @ZackR and @flintknapper mentioned a few posts back. Perhaps it would resolve once running...

Put it back together with a new valve cover gasket. Remarkably the other hoses including original PHH still looking good. The PCV hose could use to be replaced - unfortunately should've replaced the PCV grommet in the valve cover while it was off, but didn't think of it.

After initial startup and after chugging and coughing out a bunch of smoke it's running nice. Tested compression once more after it was warmed up: 205-210-205-210-210-195. A bit high -- maybe carbon on the pistons or in the chambers?

A couple tips off the top of my head, (in case I refer back to this again):
- Removing the heater valve from firewall makes it much easier to work on #6 spark plug
- No torque wrench needed on the valve cover bolts. A small 1/4 drive socket set works well; just feel for when the gasket is compressed and the actual cover (metal lip) contacts the head. At that point it doesn't take much, not even 1/4 turn, maybe 1/16 of a turn. Also use 4 small dots of RTV black on the timing chain cover where half moons are installed, 2 small dots for each half moon, one at each 'joint'. (before setting the cover down).
- May as well replace the PCV grommet anytime the valve cover is off

 

[ceylonfj40nut]

Check your fuel pump. They have issues when not used for a while. @CenTXFJ60 has had several issues on these pumps.

 

[Kernal]

Glad you got it started. Spark plug tube seals (6) could be replaced along
with the PCV grommet while the valve cover is off.