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240 High-Amp Alternator Belt Idler Pulley Project

I agree that swapping to a 7/9 layout is relatively easy. An added benefit is that the alternator gets relocated to the cold side of the engine.

Ok, then how about I just like doing things the hard way?

I have the bracket now in steel. 1/4 inch plate. had a local shop with CNC plasma cut it. Not the prettiest and not as accurate as I had asked for. Damned hillbillies. But it'll serve its purpose for proof of concept or not.
Dave
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I agree that swapping to a 7/9 layout is relatively easy. An added benefit is that the alternator gets relocated to the cold side of the engine.

Biggest benefit in my view: also more room for turbo stuff.

I hated it when my stereo went into undervoltage protect mode because the alternator was barely hanging on for dear life in traffic during a hot day.
 
Biggest benefit in my view: also more room for turbo stuff.

I hated it when my stereo went into undervoltage protect mode because the alternator was barely hanging on for dear life in traffic during a hot day.

You're preaching to the choir.

Anyway, my temperature related voltage drop has been cured by the new Mechman.
Now it's zero change in voltage output. 14.7v all day.
Dave
 
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I'm running a DR44 based Mechman as well.

Can you or anyone else school me more on the alternator these Mechmans are based on? Ok, DR44? So it's a GM or Delco unit? Anyone know what cars the DR44 were/are used on?

Mechman was tight-lipped on any of this and what they did to make it fit the Volvo. Were there actual modifications done to the case? It's hard to tell.
Dave
 
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OT: I always thought the double belt was due to the mechanical fan.

7/9's ran the fan/water pump off a single belt. The only disadvantage I see to that system is that if one is cruising along the highway and the power steering belt breaks, there's not going to be an indication that the water pump is no longer spinning. At least with the stock 240 system in the event that both alternator belts are shed, at least the alternator light will come on and hopefully get noticed before the engine overheats.
 
I believe it was a custom case for our engines. The DR44's came on stuff like the Tahoe's, Suburban's, that kinda thing. Eric (badvolvo) should have more details.
 
Wouldnt your idler pulley create premature belt fatigue from being tensioned on the "outside" of the belt? In all my years of working on cars, I've never seen a v belt tensioned on the outside. Was taught many years ago v belts should never be tension that way due to the very reason i mentioned.
 
Wouldnt your idler pulley create premature belt fatigue from being tensioned on the "outside" of the belt? In all my years of working on cars, I've never seen a v belt tensioned on the outside. Was taught many years ago v belts should never be tension that way due to the very reason i mentioned.

All of these things here are things that I was thinking. :nod:
 
Dave when I come over saturday we can take my alternator off and compare or just look at it. Its sits damn near on top and to the right. Its the stock unit from a chevy 5.3L
 
Wouldnt your idler pulley create premature belt fatigue from being tensioned on the "outside" of the belt? In all my years of working on cars, I've never seen a v belt tensioned on the outside. Was taught many years ago v belts should never be tension that way due to the very reason i mentioned.

So maybe a belt doesn't last as long? Currently I'm getting a few thousands miles before they need attention because of the slipping, requiring more tension, more wear, and more slipping, and so on. So I can make keep making the tension even tighter and replace belts more often or try something unconventional.

I've read a LOT about this subject and there is only opinions on back-side idlers. No facts. Opinions say it'll last fewer miles, but will do better if using a more flexible cog style belt, which I am.

So assuming this installation is a success and if it then lasts my entire trip to Calif and back in September, then I'll be ahead. But I'll bring an extra set of belts just in case.

Did a test fit and now making some adjustments. I already have a few small design changes documented that will increase adjustability.

Right now I think I want to re-clock the case on my alternator 90 degrees. That plug at the top sits at 12 o'clock and is getting a bit close to my turbo diaphragm. Has anyone done that to an alternator like this? I've never taken one like this apart before.
Dave
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BTW, those spacers are 1.5 inches long. I think I forgot to mention that. Bought them from Grainger.
Dave
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Easy? No. But I agree it could be a better setup. Better to have the alternator on the non-exhaust side.
Parts needed from my imagination: New mounting bracket for alternator and AC. New PS bracket to mount PS on exhaust side. New PS pump. New PS hoses. Introduce a PS reservoir where there isn't one in my car now.
Anything else?

Still, is there anyone who can say for certain there will be NO BELT SLIPPAGE with a 740 single belt using a monster alternator pushing millions of amps?

For now, I'm moving forward with this. If it works like I expect, maybe it'll help a few others in a similar situation instead of suggesting they rearrange all their accessories.

my 84 has a 740 style setup. the only change you have to make is grabbing a longer return line for the reservoir and just make the high pressure line. i used the HP line that came on the car and got some nasty good hoseclamps. been a few years with no problems. or you can have a shop make the line, and that still pretty cheap.

the bracket on that side is the same for the pump and alternator. the long bolt drops out and you move them around. coming from a guy who never cares for his car mechanically, ive had zero belt slip since then. 740 routing wraps the belt really nicely on the pulley.

that said, the new tensioner setup here is super sick, and id have definently considered it way back when.
 
I have reclocked the old Bosch style, no issues, dunno about yous though. You mentioned it being a Mechman? That front case half is much different than mine...
 
I have reclocked the old Bosch style, no issues, dunno about yous though. You mentioned it being a Mechman? That front case half is much different than mine...

Yeah, I took a few old Bosch alternators apart years ago for powder coating. Those were pretty easy. Newer style alternators like this are foreign to me. Hopefully no surprises like springs and ball bearings exploding all over the room when I open it.
 
I have reclocked the old Bosch style, no issues, dunno about yous though. You mentioned it being a Mechman? That front case half is much different than mine...

That looks like a custom cnc case. The stock gm case doesn't look as blingy
 
That looks like a custom cnc case. The stock gm case doesn't look as blingy

Yeah, Mechman bling version. Reclocking completed. Was much was easier than I thought. Easier than I recall the Bosch being too. Maybe more progress tomorrow.
 
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Gotcha. My Mechman is just the normal cast case.

Good to know it's easy to reclock if needed. I'm on the hunt for an alternator for the Dodge, might see if I can source a DR44 and adapt it over...
 
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