Halp! Engine Crank Pulley & V belt to Serp conversion.

**Grimace** · 12th November 2013, 08:27 AM

My scenario. I have a 4.6 block with a 3.5 v belt front cover configuration that uses some 3.9 pulleys/ancillaries.

Last night I was stripping the front end to replace the 3.5 v belt front cover with a second 3.9 v belt front cover as the 3.5 front had a crack at base around the Distributor driven oil pump gears and had been leaking since it went in.

I was on a roll, but discovered something odd that was seemingly never picked up when the engine was assembled.
The crank pulley was floating on the crank, it had almost an inch of movement (in and out).
At first I thought the crank pulley bolt had come loose but when I cleaned it all up removed it and replaced and checked I was presented with this;

And this is the bolt and spacer that was holding this all together;

So put simply the 4.6 crank nose is too long???
I can not believe the crank nose and key as well as the pulley have survived this.

If any one can shed some light on how I can rectify this dilemma it would be much appreciated.
Please also keep in mind that I have a complete serpentine belt front end that I can utilise if it will solve the issue? I would actually prefer to swap it all back to serp belt, but so far have not been able to find the info on what is and is not required.

**bee utey** · 12th November 2013, 08:41 AM

All 4.6 conversions to distributor style front covers need a spacer ring on the front of the crank to allow for the extra crankshaft length. A suitable piece of steel pipe could be machined up, or a segment of an old front pulley. Shame on your engine builder for not knowing this!

Example:

Crank Spacer 4.0 & 4.6 - The Wedge Shop

**peter51** · 12th November 2013, 08:47 AM

That harmonic balancer is incorrect. It looks like it has a tapered bore. The one on my p38 does not look like that. The bolt and washer are correct.

**Grimace** · 12th November 2013, 09:22 AM

Originally Posted by bee utey

All 4.6 conversions to distributor style front covers need a spacer ring on the front of the crank to allow for the extra crankshaft length. A suitable piece of steel pipe could be machined up, or a segment of an old front pulley. Shame on your engine builder for not knowing this!

Example:

Crank Spacer 4.0 & 4.6 - The Wedge Shop

Thanks bee utey, It has been suggested that this will be the simplest solution.
As for the engine builder, not sure about the first time around, but I have only myself to blame for this as I bolted that pulley on when I installed the 4.6 to the Rangie.

Originally Posted by peter51

That harmonic balancer is incorrect. It looks like it has a tapered bore. The one on my p38 does not look like that. The bolt and washer are correct.

It's a 3.9 v belt pulley and balancer from a 1990 range rover hence the difference in appearance. Hopefully that is not an issue as I just want it back together for Coffs trip in a couple of weeks.

Been so lucky not to have any damage!!!

**Grimace** · 12th November 2013, 09:36 AM

Looking at this a little bit more, I assume the spacer has the keyway groove?
Cant see any in that image from the wedge shop?

If you look at my first post the image clearly show the keyway also protrudes past the pulley, so any spacer is going to need to be keyed to suit?

IGNORE THE ABOVE!
I just realised the keyway does not protrude past the end face of the pulley. So that spacer or any simple non keyed spacer will work.

**PLR** · 12th November 2013, 10:30 AM

G`day

if you have an old crankshaft timing gear you can cut the teeth off it so`s it fits inside the balancer , it`s what ours has had for at least 15 years without problem or if you don`t like that idea you can use the gear less the teeth dia for your measurements .

The bought spaces don`t have keyways .

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