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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
So, the late cross-flow thermo housing with air pump mounting lug showed up, and I did a quick clearance study.

The profile of the cantilever portion of the front mount, as cut to accommodate the vertical flow thermo housing, also accommodates the cross flow housing that lacks the air pump mounting lug (first four pics). Both housings are available from APT, if not Moss.

The reliefs for the thermo housing and the corner of the valve cover take just a few moments with a half-round file. You use the flat side to make the corner--which is also the fulcrum--nice and sharp to mate with the edge of the head. You also have to round the lower edge of the vertical face of the angle iron just slightly to accommodate the slight flare next to where the temp sender goes.

The third style housing, with the air pump lug, would take too much material removal from the angle iron for my taste.

Much easier is to just use a flat bar (oriented vertically) on the aft side of the housing's air pump lug (to the right here) in place of the angle iron, with the inboard end of the bar again resting against the side of the head to transfer force there and prevent it from pivoting around the axis formed by the air pump bolt.

As you can see, one could either use a spacer (I sourced some on Amazon, Home Depot, and elsewhere) to bolt the tensioner's upper mounting ear to the bar--which would run just aft/right of the front surface of the angle iron in this photo--or use a short piece of bar to attach the tensioner's ear to the forward side of the housing's air pump lug (to the left). Simple.

Or... easier still would be to ditch the housing with the lug and go with the cross-flow model sans the lug. They're not very expensive new at APT and available used, too.

Joel



Edited 2 time(s). Last edit at 2018-01-08 09:24 AM by Yankeedriver.


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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
A weekend off! Sheer luxury, as they say...

So, finally got to the serpentine belt routing, tensioner and idler pulleys, and alternator adjustment--sorted!

The first photo shows the belt routing--with the twine around the flat, front part of the crank pulley, similar to how it runs on the serpentine version I'll put on mañana.

The idler pulley is simplicity itself: you just put some 3/8"-24 threaded rod in place of the original belt tensioning bolt, add a couple of cheap spacers from Amazon, put washers and nylock nuts front and back... and voila. Alignment is simple by adding washers or shimming the alternator--but it all lined up perfectly 'as is.'

The alternator is unbelievably easy. Just take one of the longer thermostat housing, dual-thread pitch studs from Moss, et al. (which cost .89 cents) and use it to replace the bolt that used to go through the engine plate into the block, then add two 5/16" spacers of the sort that are used in spring-lowering kits (these may be from mine before I bought lowered springs), and simply use the OEM adjustment strap.

Why keep an adjustment strap? Because this allows you to 'pre-load' the belt, so that the auto-tensioner can be fine-tuned. Works great to dial in just the amount of belt-deflection that you want the spring-loaded tensioner to provide. Also, of course, you get to reuse the OEM strap. This stuff is just straight bolt-on, based on parts you can get on the internet for just a few bucks.

The Avalanche belt tensioner? It simply attaches to the alternator pivot bolt, then you just drill a hole in the front of the angle iron, add another of the 3/8" spacers from Amazon (they come in a pack of just the right amount to do this conversion) and a big nut or some washers over more of the 3/8"-24 threaded rod with nylock nuts. Presto.

And how about R&Ring the belt? Without a doubt, the easier setup on any car I've worked on. The tensioner is right on top, directly in front of you when you open the bonnet (last photo).

Tomorrow, I'll finish the front mount--which is just more of the 3" steel Home Depot plate used for the rear mount, scalloped to go around the blower's snout, and bolted up. If I have time, I'll lift the engine a bit and swap out the crank pulleys, and dart to the auto parts store for the serpentine belt. As posted earlier in this thread, this conversion uses a readily available Dayco belt that costs <$20.

Joel



Edited 1 time(s). Last edit at 2018-01-13 05:49 PM by Yankeedriver.


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mster50 Silver Member Mike Sterling/A
Zanesville, OH, USA   USA
1980 MG MGB
In reply to # 3661330 by Yankeedriver A weekend off! Sheer luxury, as they say...

So, finally got to the serpentine belt routing, tensioner and idler pulleys, and alternator adjustment--sorted!

The first photo shows the belt routing--with the twine around the flat, front part of the crank pulley, similar to how it runs on the serpentine version I'll put on mañana.

The idler pulley is simplicity itself: you just put some 3/8"-24 threaded rod in place of the original belt tensioning bolt, add a couple of cheap spacers from Amazon, put washers and nylock nuts front and back... and voila. Alignment is simple by adding washers or shimming the alternator--but it all lined up perfectly 'as is.'

The alternator is unbelievably easy. Just take one of the longer thermostat housing, dual-thread pitch studs from Moss, et al. (which cost .89 cents) and use it to replace the bolt that used to go through the engine plate into the block, then add two 5/16" spacers of the sort that are used in spring-lowering kits (these may be from mine before I bought lowered springs), and simply use the OEM adjustment strap.

Why keep an adjustment strap? Because this allows you to 'pre-load' the belt, so that the auto-tensioner can be fine-tuned. Works great to dial in just the amount of belt-deflection that you want the spring-loaded tensioner to provide. Also, of course, you get to reuse the OEM strap. This stuff is just straight bolt-on, based on parts you can get on the internet for just a few bucks.

The Avalanche belt tensioner? It simply attaches to the alternator pivot bolt, then you just drill a hole in the front of the angle iron, add another of the 3/8" spacers from Amazon (they come in a pack of just the right amount to do this conversion) and a big nut or some washers over more of the 3/8"-24 threaded rod with nylock nuts. Presto.

And how about R&Ring the belt? Without a doubt, the easier setup on any car I've worked on. The tensioner is right on top, directly in front of you when you open the bonnet (last photo).

Tomorrow, I'll finish the front mount--which is just more of the 3" steel Home Depot plate used for the rear mount, scalloped to go around the blower's snout, and bolted up. If I have time, I'll lift the engine a bit and swap out the crank pulleys, and dart to the auto parts store for the serpentine belt. As posted earlier in this thread, this conversion uses a readily available Dayco belt that costs <$20.

Joel

Is that enough contact area to run the alternator? I am not saying is isn't, I have just always seen more.

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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3661339 by mster50
In reply to # 3661330 by Yankeedriver A weekend off! Sheer luxury, as they say...

So, finally got to the serpentine belt routing, tensioner and idler pulleys, and alternator adjustment--sorted!

The first photo shows the belt routing--with the twine around the flat, front part of the crank pulley, similar to how it runs on the serpentine version I'll put on mañana.

The idler pulley is simplicity itself: you just put some 3/8"-24 threaded rod in place of the original belt tensioning bolt, add a couple of cheap spacers from Amazon, put washers and nylock nuts front and back... and voila. Alignment is simple by adding washers or shimming the alternator--but it all lined up perfectly 'as is.'

The alternator is unbelievably easy. Just take one of the longer thermostat housing, dual-thread pitch studs from Moss, et al. (which cost .89 cents) and use it to replace the bolt that used to go through the engine plate into the block, then add two 5/16" spacers of the sort that are used in spring-lowering kits (these may be from mine before I bought lowered springs), and simply use the OEM adjustment strap.

Why keep an adjustment strap? Because this allows you to 'pre-load' the belt, so that the auto-tensioner can be fine-tuned. Works great to dial in just the amount of belt-deflection that you want the spring-loaded tensioner to provide. Also, of course, you get to reuse the OEM strap. This stuff is just straight bolt-on, based on parts you can get on the internet for just a few bucks.

The Avalanche belt tensioner? It simply attaches to the alternator pivot bolt, then you just drill a hole in the front of the angle iron, add another of the 3/8" spacers from Amazon (they come in a pack of just the right amount to do this conversion) and a big nut or some washers over more of the 3/8"-24 threaded rod with nylock nuts. Presto.

And how about R&Ring the belt? Without a doubt, the easier setup on any car I've worked on. The tensioner is right on top, directly in front of you when you open the bonnet (last photo).

Tomorrow, I'll finish the front mount--which is just more of the 3" steel Home Depot plate used for the rear mount, scalloped to go around the blower's snout, and bolted up. If I have time, I'll lift the engine a bit and swap out the crank pulleys, and dart to the auto parts store for the serpentine belt. As posted earlier in this thread, this conversion uses a readily available Dayco belt that costs <$20.

Joel

Is that enough contact area to run the alternator? I am not saying is isn't, I have just always seen more.

Hi, Mike.

Yes, it should be fine. However, the neat thing about this setup is, if you want to wrap the belt around the alternator pulley some more, all you have to do is use the alternator adjustment strap to lift the alternator. You can also just add a little 2" tab/extension--rather than putting the all-thread through the angle iron itself--to move the tensioner anti-clockwise and thus into the belt more, effectively wrapping it further around the alternator pulley.

Joel


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mster50 Silver Member Mike Sterling/A
Zanesville, OH, USA   USA
1980 MG MGB
Good enough. I can't wait to see it in final form and running.

Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3661350 by mster50 Good enough. I can't wait to see it in final form and running.

You bet--me, too!

You know, Mike, I just realized an alternative, based on your observation. If I move the lower tensioner's mounting bolt up using a little tab--rather than lowering the upper one--and change the belt-routing so as to pass the belt over the idler and under the (lowered) alternator before heading up to the blower, the tensioner would then depress the belt running between the blower and water pump. I might get better wrap-around on the alternator that way--but still am well within the lengths of belts available.

Lemme ponder that tonight, and I may run another twine routing study tomorrow, and let's see what's what. It'll be fine either way, but this might give me a bit more wrap.

Joel


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pinkyponk Avatar
pinkyponk Gold Member Adrian Page
Berwick, NS, Canada   CAN
I would be extremely surprised if your alternator operates properly with that little wrap. I would try to get the tensioner on the "slack side" of the crank pulley. (that long run)

Nice to see you making such good progress. thumbs up

Adrian



Home built Eaton M62 Supercharger with 9psi boost, "stock" high ratio rocker arms, 8:1 compression, Piper 270 cam, ported head, matched manifolds, CB Performance computerized ignition.

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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3661387 by pinkyponk I would be extremely surprised if your alternator operates properly with that little wrap. I would try to get the tensioner on the "slack side" of the crank pulley. (that long run)

Nice to see you making such good progress. thumbs up

Adrian

Hi, Adrian.

Minimum required with a serpentine belt is 1/4 of the pulley (I uploaded lots of diagrams in an earlier post), and I agree it may be a little shy of that right now. I can achieve that by adding the tab I mentioned earlier, which tips the tensioner down into the run more.

However, I ran a string study just now for the alternate belt routing I mentioned to Mike... and I realize that doing so may enable an even simpler tensioner configuration that would also result in greater wrap. I may fiddle with that tomorrow.

Joel


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Denis Avatar
Denis Denis Hill
Bearii, Nth Victoria, Australia   AUS
Joel you have your tensioner on the tight side of the belt. A spring loaded tensioner wont work properly there. Slack will build up after the crank pulley in a boost situation and thats where the tensioner should be. If with your setup you cant put the tensioner on the slack side you may need to run a fixed tension adjuster. The way you have it the pull on the belt will actually unload the tensioner causing more slack and probably derail. You may be able to fit the tensioner at the slack side of the belt almost at the blower as a next best. Not trying to pick its just I have come across these problems before. Denis



68 B roadster, Daffodil yellow, supercharger, Burgess SC head, SC cam, Mikuni HSR 48 carburetor and engine built for supercharging.

73 BGT V8 conversion starting with a bare shell. Built the engine early in 2016 with high comp pistons and a few other nice bits. Started on the body late 2016 and found Its a lot of work and expense starting from scratch. Did the work myself, mechanical, body. paint etc all except the interior trim.
Finished and going well, great to drive and quick. Future mods, maybe an increase in gearing but not for a while.

Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3661493 by Denis Joel you have your tensioner on the tight side of the belt. A spring loaded tensioner wont work properly there. Slack will build up after the crank pulley in a boost situation and thats where the tensioner should be. If with your setup you cant put the tensioner on the slack side you may need to run a fixed tension adjuster. The way you have it the pull on the belt will actually unload the tensioner causing more slack and probably derail. You may be able to fit the tensioner at the slack side of the belt almost at the blower as a next best. Not trying to pick its just I have come across these problems before. Denis

Denis,

Thanks for the input. I am not too worried about derailing; I am concerned about slippage, though. As I've said, I'm going to try the alternate routing which I expect should solve both concerns.

Joel


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trevorwj Avatar
trevorwj Trevor Jessie
Louisville, KY, USA   USA
Slack belt over a long span with vibration and air currents .. you could very well have tracking issues. It may be time to step back and punt.



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refisk Avatar
refisk Rick Fisk
Frankenmuth, MI, USA   USA
Are serpentine belts with ribs on both sides available? Will the alternator work properly if you turn it anticlockwise?

EDIT: Did a little searching and found the answer is yes and yes. Double sided belts are readily available and an alternator can run in either direction. The only caveat is that the fan on the alternator must be re-oriented correctly to cool the alternator. You would have to remove the idler wheel and relocate the tensioner Joel, but running the belt under the alternator pulley would provide a much larger pulley contact area.



Edited 2 time(s). Last edit at 2018-01-14 10:01 AM by refisk.

mster50 Silver Member Mike Sterling/A
Zanesville, OH, USA   USA
1980 MG MGB
Doesn't the engine turn clockwise looking from the front? The belt would pull tight from the crank to the hardest turning accessary, I would think that would be the blower, and be slack and bounce from there, the blower, back to the crank. I think the tensioner needs to be on the long length between crank and blower. That would reduce whip in the belt on that long length.

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Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3661635 by mster50 Doesn't the engine turn clockwise looking from the front? The belt would pull tight from the crank to the hardest turning accessary, I would think that would be the blower, and be slack and bounce from there, the blower, back to the crank. I think the tensioner needs to be on the long length between crank and blower. That would reduce whip in the belt on that long length.

Yes, Mike, that's what people are concerned with.

Joel


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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3661615 by refisk Are serpentine belts with ribs on both sides available? Will the alternator work properly if you turn it anticlockwise?

EDIT: Did a little searching and found the answer is yes and yes. Double sided belts are readily available and an alternator can run in either direction. The only caveat is that the fan on the alternator must be re-oriented correctly to cool the alternator. You would have to remove the idler wheel and relocate the tensioner Joel, but running the belt under the alternator pulley would provide a much larger pulley contact area.



In reply to # 3661615 by refisk Are serpentine belts with ribs on both sides available? Will the alternator work properly if you turn it anticlockwise?

Good morning, Rick.

Now, that is a helpful suggestion - thank you!

First of all, I agree there is no problem with running an alternator the opposite direction; it generates the same current either way. As for a reverse fan, so the diodes don't overheat, Corvairs are one of the few production cars I'm aware of that ran the alternator in reverse, but their pulley and fan are one piece and used an old V-belt.

However, one could just recurve the fan blades--probably not hard to do with a ball peen, drift or piece of rebar, and a vise. I had forgotten all about that option, which I remember being done on hot rods in the service station I grew up working in. I have also seen it done on old farm irrigation pumps, generators, etc. Thanks for sparking the old memory!

Second, it appears you're right that Dayco, Gates, and Continental (and possibly others?) make double/dual-sided serpentine belts. I'm having a little trouble finding them in Dayco's search-by-dimension online feature, but I'll figure that out. The lengths available may be more limited than the regular belts.

As for the idler, it may be useful to take up extra length if all I find are longer belts. The 'reverse alternator' routing would go: crank to blower; blower down to and under alternator; up to H2O pump; down around idler; then back to crank. Or, if the extra length weren't needed, straight from H2O pump to crank.

Cool. Let me fiddle with this a bit...

*Edit: however, the narrowest I can find is 5 ribs, so I'd have to have the crank pulley I designed made up, after all. However, it'd be cheaper than Moss's 4-rib version anyway. So, perhaps not a bad thing.

Joel



Edited 1 time(s). Last edit at 2018-01-14 11:07 AM by Yankeedriver.


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