harmonic balancer question

[kojak70]

I have tried to search for this but am not geting the answer i need. I have a 1985 258 engine i am rebuilding to go in my 1989 yj. It has the 4.2 also. My 89 is equipped with the serpentine belt system. the 85 engine has the v belt hb. i think that the serpentine belt hb is the same as the 4.0 hb.?? if that is true then i need to take 10mm off the snout like you all do for stroker setups. I need to know if this is the case. is the 1989 serpentine belt hb the same as 4.0 hb and ttaking 10mm off the snout of my 1985 4.2 crank will make this work for my serpintine belt accessories. thanks for any info or direction in this matter. Happy Jeeping

[467076rcolton]

I don't know if this helps. but my crank is out of an 87-90 4.2, which is the years that they had the 2 inch snout. and I am running it in a 95 4.0 block with a serpentine belt and I didn't trim anything off and everything lines up great

[604rail_king]

If you machine 10mm off the crank snout, you will need to have the key way hole remachined.

Using a 10mm spacer goes between the hb and the hb bolt to keep the jb from walking.

[IH 392]

If you machine 10mm off the crank snout, you will need to have the key way hole remachined.

Why?, just grind off the ittybit that sticks out, no need to add more expense,

[604rail_king]

For my crank, taking 10mm off the snout would remove half the keyway pocket. Meaning your key way won't fit. Take a quick look again at your crank to see

[IH 392]

For my crank, taking 10mm off the snout would remove half the keyway pocket. Meaning your key way won't fit. Take a quick look again at your crank to see

Here's the modified snout with and without the key in it, maybe a 1/8"?



And here's the chunk I took off less the 1/8" wide cut off tool.


I don't have a problem with it??