rear main seal on 3fe, not a factory size? help?

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so i got a dealer gasket kit to rebuild my 3fe.

1991 fj80. no big deal. problem number one, the oil pan gasket looked like it was glued together by a 3 year old. it had 1mm gaps in the glue joints. so i made them give me a new one of those.

then i thought the rear main seal was the wrong one because it was too big on the i/d by a good 10mm. the seal i pulled out was an "lyo" part number 105929. which yields almost no google results. turns out it doesn't matter anyway because even that was the wrong one. which looks like the reason it was leaking.

the dimensions of the seal i took out are 105mm id x 120mm od x 11m depth. looks like the toyota part is 110mm id x 120mm od x 11mm depth.

however the crank seal itself is only 100 mm. was this thing machined down at some point and now i have to look for some obscure seal? if so, do i look for one that is exactly 100 mm? or do i need to find one smaller so it holds a sealing surface?
 

cruiserdan

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There is only one possible 3FE rear main seal, 90311-99005. It is used in both FJ62 and FJ80.

My Mickey-Mouse plastic ruler puts the ID at ~103mm.


What is the part number or your overhaul set?

problem number one, the oil pan gasket looked like it was glued together by a 3 year old. it had 1mm gaps in the glue joints.

I have never seen this with a factory gasket....I smell an aftermarket part.

Does the oil pan-side of the gasket have one red stripe on one side and two red stripes on the opposite side near the back end?
 
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There is only one possible 3FE rear main seal, 90311-99005. It is used in both FJ62 and FJ80.

My Mickey-Mouse plastic ruler puts the ID at ~103mm.


What is the part number or your overhaul set?



I have never seen this with a factory gasket....I smell an aftermarket part.

Does the oil pan-side of the gasket have one red stripe on one side and two red stripes on the opposite side near the back end?

it has one skinny red stripe, and one fatter smeared stripe in that location.

uploading some photos of the oil seal. its the correct part no. but it looks like someone machined down the crank from 105mm to 100 mm.

the dimensions for the correct seal are 105x120x11mm. what i need is 100x120x11mm now.
 
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in this picture, (sorry about the graininess) you can see the face of the crank and then in the middle you can see the lip of what i am guessing was the original diameter of the crank end.
2011-06-11 09.02.28.jpeg
 
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this is the "lyo" seal i took out. obviously aftermarket.

this gap is just as big with the toyota replacement. i am now beginning to believe that i have the "correct" gasket, but someone, somehow machined this crank end down.

when you mike the seal, it should be about where it deforms and pushes against the metal framework of the seal. which is 105mm. the 103mm should be the inner lip of the seal so it maintains constant contact.
2011-06-11 08.57.02.jpeg
 

cruiserdan

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Very interesting on the pan gasket, That is a new one on me (the poor assembly, that is). The red marks indicate the gasket is for a 3FE so that matches up.

The part number for the kit is correct for a 3FE.

I just pulled a 2F rear main off the shelf and the ID of that seal (by the above-mentioned precision device) is ~98mm.

It sounds like you have a 2F crank?
 
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the dealership has a 2f seal. so i am going down to pick it up and see if it fits.

yes, this motor was clearly "gotten into" because all the freeze plugs say "doorman" and are put in with orange rtv. which also leads me to believe it was not done to factory spec in any way. :lol:

which again is probably why my head gasket failed....
 
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not sure which part number it is, but the 2f seal fits. well, it will fit. its hard to get in there, which is how it should be. all the sizes line up correctly. and the good news is that it was only $68 with tax... :crybaby:
 
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yes, it is the 99001. and it fits perfectly. so is it common to stick a 2f crank in a 3fe?
 
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that is really weird. i see that the 2f has a longer stroke, but it would seem that the rods and pistons would have to be different too?
 

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