85 2wd C&C Dump 4x4 Conversion

[bp17oang]

Gary was looking into this before he decided to go with a polygroove front dress.

Perhaps he has some numbers for the front crank pulleys?

I have been using mine with a single belt and it's been fine with a Load Response Control regulator.

Okay. I have two options if I'm going to run one. I can run it directly off the crank pulley which would be the pulleys closest to the engine or I can run it up around the water pump also. You see any disadvantage or advantage to doing it one way or the other?

[ArdWrknTrk]

Okay. I have two options if I'm going to run one. I can run it directly off the crank pulley which would be the pulleys closest to the engine or I can run it up around the water pump also. You see any disadvantage or advantage to doing it one way or the other?

I can only say that my truck (with a 3 sheave crank pulley) has the belt around only the rearmost and the alternator.

I think this is good because it gives more wrap, and therefore more belt traction.

My water and power steering pumps are driven by a matched pair of belts from the front most pair of sheaves.

But I don't know how your pulleys align, or what is driven off the forth sheave of the crank.

[Gary Lewis]

I can only say that my truck (with a 3 sheave crank pulley) has the belt around only the rearmost and the alternator.

I think this is good because it gives more wrap, and therefore more belt traction.

My water and power steering pumps are driven by a matched pair of belts from the front most pair of sheaves.

But I don't know how your pulleys align, or what is driven off the forth sheave of the crank.

I agree - use the arrangement with the most wrap.

As for the pulleys to use, I found a pulley from another engine, Windsor I think, that had two matched sheaves the right size. I might be able to come up with the part numbers on it if you want.

As for the alternator, I ordered a pulley that was supposed to have two sheaves the same size, but it didn't as one was smaller than it was supposed to be. So I enlarged that sheave on the lathe.

I've not run that combo yet 'cause it is for Dad's truck, but if I had to do it over again I'd go with one belt.

[ArdWrknTrk]

I agree - use the arrangement with the most wrap.

As for the pulleys to use, I found a pulley from another engine, Windsor I think, that had two matched sheaves the right size. I might be able to come up with the part numbers on it if you want.

As for the alternator, I ordered a pulley that was supposed to have two sheaves the same size, but it didn't as one was smaller than it was supposed to be. So I enlarged that sheave on the lathe.

I've not run that combo yet 'cause it is for Dad's truck, but if I had to do it over again I'd go with one belt.

Gary, all the dual sheave pulleys that came on these trucks used a smaller belt to drive the AIR pump(s).

I'm not sure if both were the same size on the L&L pulley I sent you, but there are 17mm bore pulleys available with same size sheaves.

But you might need a lathe to get the offset correct, so it lines up with the crank.

That is one disadvantage of the 3G. Its shaft is short because there is no external fan, and it was always intended for a deeply dished polygroove belt pulley.

Remember, with stock alternator mounts the alternator belt is closest to the engine.

You don't want to move the fan, power steering and AC forward just to accommodate an alternator.

You don't want a backspaced crank pulley that will cover the harmonic balancer, and it's timing marks.

[ArdWrknTrk]

Gary, all the dual sheave pulleys that came on these trucks used a smaller belt to drive the AIR pump(s).

I'm not sure if both were the same size on the L&L pulley I sent you, but there are 17mm bore pulleys available with same size sheaves.

But you might need a lathe to get the offset correct, so it lines up with the crank.

That is one disadvantage of the 3G. Its shaft is short because there is no external fan, and it was always intended for a deeply dished polygroove belt pulley.

Remember, with stock alternator mounts the alternator belt is closest to the engine.

You don't want to move the fan, power steering and AC forward just to accommodate an alternator.

You don't want a backspaced crank pulley that will cover the harmonic balancer, and it's timing marks.

I also think the larger diameter L&L pulley would drop the ratio enough that belt chirp at starting would be eliminated.

(I'm pretty sure this is what Bill did with his 3G.).

[bp17oang]

I also think the larger diameter L&L pulley would drop the ratio enough that belt chirp at starting would be eliminated.

(I'm pretty sure this is what Bill did with his 3G.).

[Gary Lewis]

Gary, all the dual sheave pulleys that came on these trucks used a smaller belt to drive the AIR pump(s).

I'm not sure if both were the same size on the L&L pulley I sent you, but there are 17mm bore pulleys available with same size sheaves.

But you might need a lathe to get the offset correct, so it lines up with the crank.

That is one disadvantage of the 3G. Its shaft is short because there is no external fan, and it was always intended for a deeply dished polygroove belt pulley.

Remember, with stock alternator mounts the alternator belt is closest to the engine.

You don't want to move the fan, power steering and AC forward just to accommodate an alternator.

You don't want a backspaced crank pulley that will cover the harmonic balancer, and it's timing marks.

Jim - The pulley I used was off a much earlier engine, IIRC, before the AIR pump. And it took a lot of searching to find it.

I'll check the L&L pulley tomorrow to see what the belt sizes are.

[ArdWrknTrk]

Now you see why the wider (8.25") mounting is a better fit for the bracket.

It allows the fatter (148mm) body of the 130A 3G to clear the bracket, and then the adjuster bolt sets in the middle of the J shaped slot.

Often the 3G without a LRC regulator will chirp or squeal on startup, until the belt has a moment to gain traction.

If your truck doesn't do that then it's good!

You'd need to put a real load on the electrical system to pull down the alternator enough to slip a single belt (around 105A, from what I saw on Ryan's video)

The Taurus/Lincoln fans can hit 80A inrush when they kick on high.

I am not familiar with the sheaves set up on the fan pulley like yours has.

Mine only has two there.

[kramttocs]

Now you see why the wider (8.25") mounting is a better fit for the bracket.

It allows the fatter (148mm) body of the 130A 3G to clear the bracket, and then the adjuster bolt sets in the middle of the J shaped slot.

Often the 3G without a LRC regulator will chirp or squeal on startup, until the belt has a moment to gain traction.

If your truck doesn't do that then it's good!

You'd need to put a real load on the electrical system to pull down the alternator enough to slip a single belt (around 105A, from what I saw on Ryan's video)

The Taurus/Lincoln fans can hit 80A inrush when they kick on high.

I am not familiar with the sheaves set up on the fan pulley like yours has.

Mine only has two there.

The L&L sure looks like the two are the same just visually with the one mostly obstructed by the belt.

I agree that you shouldn't need two belts in the normal usage scenario. Kind of a shame the outer (A/C) crank groove is smaller though in case one did want to run two.

[ArdWrknTrk]

The L&L sure looks like the two are the same just visually with the one mostly obstructed by the belt.

I agree that you shouldn't need two belts in the normal usage scenario. Kind of a shame the outer (A/C) crank groove is smaller though in case one did want to run two.

Outer groove is for the thermactor air injection reaction pump(s).

They are jackbelted off the alternator.