My 94 FZJ80 idles very low and dies off after warming up. Over the weekend I did the typical replacements oil pump gasket, and FMS, was going to do the dizzy O-ring however after discovering that the oil was coming from the actual inside of the shaft, opted not to. Also replaced all three V Belts as the old ones were old and worn. Everything went back smoothly and she started up just fine however after a couple of minutes being on, the idle started to get very slow and she eventually died. Suspected it to be timing as I might have moved the dizzy somehow, so went on to fix timing with a timing light to just over 3 degrees. Was fine for a few minutes then idle got low again and died. Anyone have any more ideas what it could be?
Bad Idle After Oil Pump and Front Main Seal Replacement (1 Viewer)
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- Thread starter
- #21
That’s the thing, there was a green puddle but no smell of maple syrup unless my nose is that bad. However will be taking pictures of smoke and puddle next start up I do! 145k? Yeah it might be time then just find it weird that it was running so smooth before I did the seals on it then all of a sudden when I turned her back on she’s stuttering and HG might be gone smh
mudgudgeon
Resident galah
If you're sure there was a puddle of coolant from the exhaust, pull spark plugs before you restart it and turn it over by hand.
Coolant in a cylinder can hydraulic lock the engine, and bend rods or crack crank shaft.
If there any sign of coolant in cylinders don't restart it
Do take pics and post.
There is nothing that you did when doing the oil pump seal and front main seal that would have caused a HG failure.
Do the proper diagnostics to determine what's really going on.
Many years ago, another guy bought a LC, was convinced he had a HG problem and tore it apart. He got in way over his head and called me for assistance. He was reading all about the HG failures here and thought he should do it.
Turns out he had a 1991 with the 3FE engine and it rarely has HG failures.
My point is, make sure that the problem really is what you think it is before going off half cocked and tearing apart stuff and costing yourself way more money and time than it needs.
Do the coolant test and pull spark plugs to see if any look steam cleaned. You may not have run it enough for that to be the case.
HG don't fail just sitting in your garage.
- Thread starter
- #25
Got it I mean would messing with the timing when I started it back up cause this? Just very odd to me that it started having problems after I did both seals.
Yeah it’s my weekend car anyway so I definitely don’t want to rush into anything as I don’t need to. I will be doing all of the things you guys mentioned before I tear anything apart or take it to a place.
Screwing up the timing will not necessarily blow the HG. It will make it not run well.
There are extremely rare circumstances that messed up timing could be a cause of HG failure, but on this low HP engine, it's extremely unlikely.
As some have said- verify the coolant "issue" first. It sounds as if you should also verify your timing (if you changed anything during previous work).
Is it possible that you lost some vacuum hose connections last time your were working on it? Vacuum leaks will cause the motor to not run properly.
Keep us posted, and best wishes!
- Thread starter
- #28
If I take out spark plugs and turn it by hand would I be able to see coolant come out or what would be the reason for me to do that other than check if they’re clean. Yeah I figured as so gonna dig in tomorrow n do these basic tests first.
ppc
M Go Blue
Did you disconnect the battery at any point?
ppc
M Go Blue
That is going to reset the ECM and will take a few restarts to relearn things and the rough idle should go away. Just start tracking down where the coolant is leaking.
mudgudgeon
Resident galah
You could potentially see coolant splash/splatter out of a plug hole.
Use a light and check each cylinder while it's at TDC to see if you can see coolant.
It only takes about a teaspoon of water in a cylinder to hydraulic lock an engine
- Thread starter
- #34
Got it will do! Def don’t want to hydro lock it didn’t realize it was that easy thanks! So to reiterate take plugs out, hand crank till each piston is at the top, and check if there’s any water/coolant? If so got it, boss.
mudgudgeon
Resident galah
Yep. Unless you have s borescope cam and can take a peek inside
Humor me, check the condition of your harmonic balancer. When ours went the engine stumbled, idle dropped, oil pressure would drop and then it would return. We went a couple of hundred miles after the mechanic gave it a once over and replaced the oil pressure sensor. After one weird start I open the hood and saw the belts out of line and the movement in the HB.
Probably not your issue, but one worth knocking off of the list.
- Thread starter
- #38
Soooo upon further review today, oil is milky and smells like coolant inside the oil filler cap. Checked spark plugs but they seemed normal, no water, went to start it up after checking n smoke from back, nothing heavy however after a minute or two started smelling the sweet smell went to turn off, let it cool down did oil change and sure enough milky oil light ish brown color.
