Need to replace sump gasket, help!!!

[glennk]

Hi Guy's,

Really need some advice on changing the sump gasket on my 4JB1T 92 MU.

Can you do this without dropping the diff or lifting the engine? really dont want to do either of these unless I really have to. Going to use Silicon Gasket.

Any help appreciated.
Glenn

[Drift]

Mine is silicone on the pan, if you are leaking a bit of oil try nipping up the bolts on the sump pan as they can work loose.
It solved my leak two years ago

[Tbone]

i need to do the same, at least i think i'm looking at the same bit, the seal around the sump pan (where the engine oil drain bolt is?), how did you get access to all the bolts? the bolts that look like they need tightening are directly over the front suspension crossmember and i can't get a socket in there. did you have to undo the four bolts attaching the crossmember? (and if so is it under tension or anything?)

[Drift]

I tightened them with a good old fashioned spanner, I had just enough room to get in there.

[greenwolverine]

Oil Pan Restore
Isuzu Bighorn 1992 UBS 69 3.1 TD
My lower oil pan was leaking out the back side, which is a common problem.
I took it off and found a couple of problems. I tested all the holes in the upper oil pan for stripping, and discovered that some of them were in fact stripped.
On the pan itself, the rim had previously been stuffed with silicone gasket maker and over-tightened so that belling had happened at the bolt holes.
First job was to provide a solution to the stripped threads. The stripping was really only at two of the holes, so I cemented in some threaded stubs with J&B weld and let that set for 24 hrs.
Next, the pan had to be trued up. I took my wife’s kitchen cutting board made of glass and put some 200 grit paper on it. You might try some finer paper but that’s all I had. You don’t want anyone to know you did this.
Anchoring the sandpaper with one hand and pulling away the pan while pushing it down with the other, I slowly worked off all the proud areas until the pan rim came up nice and flat and true.
I also bought some new bolts with wider flanges so that my thinned down bolt holes weren’t going to bell that easily again.
In between I had been constantly cleaning up the flange surface on the car with brake cleaner and mopping up drips.
Final step was to put a bead of Loctite 518 anaerobic gasket maker on the pan rim. In the manual it shows how to put the bead on the inside of the two ridges. I suppose one could put a bead on both inside and out but I decided to put this stuff to the test and did a single 3mm wide bead.
It has held beautifully on my trans pan for months.
A while back I had bought the spray can of Loctite Activator even though I did not use it on my transmission pan job. I thought that at the oil pan there is more pressure and less finicky machinery to damage so I sprayed some onto the upper oil pan flange surface (They don’t tell you how much, but I sprayed it on quite liberally). If your spray can is unused, it takes about 15 seconds before the real greenish stuff comes out.
Without any more fuss I pushed on the pan and finger-tightened all the bolts. Then in a star pattern I fixed them to a very light hand-tightness. For the life of me I couldn’t find the specs for the lower oil pan bolts. In the FSM Vol 2 page 255 it talks about oil pan bolts going all the way up to 19Nm, but going by the part illustrated there, they are talking about the upper oil pan. I have decided that no small bolt going onto aluminum parts on the engine should be tightened to more than 9 (e.g. the timing belt cover bolts).
I let everything set for another 24 hours. No more oil leaks.
*Tip for removing Loctite 518 that has hardened.
Use paint stripper from Home Depot. It will take the paint of the pan but that’s no real train smash. From all I’ve read, the anaerobic stuff is better than silicone, because it remains liquid on the inside, and whatever residue mixes with the engine fluid will eventually be flushed out. No hardened bits of silicone getting into where it shouldn’t.

[peatpatrick]

I came across this thread and just wanted to add a bit of info. I have an early 90s 4jb1t that I've transplanted into my American trooper. I've had a messy oil leak for a long while coming from the upper oil pan (not the lower one strangely) and I was able to remove it without taking off the transmission. There a 4 horizontal bolts at the back of the oil pan that are shared with the transmission you'll need to remove, and two vertical 12mm bolt that are accessible through some holes opening downwards where the oil pan and the transmission meet.
I bought an oil pan one piece gasket online that seems really high quality but I don't think I'm' going to use it. When I finally got the pan off I realized it was sealed up with the orange silicone liquid gasket except for two semi-circle gasket at either end to accommodate the main shaft. I think these have shrank a little and thats where my leaks have been coming from. My plan is clean everything up and re-use the gaskets but add some silicone on them this time. My understanding is that these are hard to find anymore. wish me luck!
Pete