Serpentine Belt / Pulley Conversion?

lookforjoe

True Classic
EDIT: Parts used as of 12/28/14

See This Post

1) Volvo 5" OD ZF PS pump 6 rib pulley (Rob found this - Dorman 300-551
2) Machine stock crank pulley to fit inside
3) Sanden 508 Serpentine Clutch
4) Gates 36322 idler pulley (x2) (EDIT: for lower idler only)
5) 1989 Toyota Corolla/ Geo Prizm Water pump pulley - redrilled for Fiat 3 bolt, cut down to 5 rib section of pulley.
6) custom idler & tensioner mounts, using stock Alt & AC brackets as base.
7) Denso, Bosch or GM 335-1068 6 rib serpentine alternator pulley
8) Gates K050523 serpentine belt (52 7/8")

revised (smaller) 3.25" w/p pulley required belt change. Using Gates K050530 now, and 2" upper idler pulley (T40284, 9128738, ATB2207) instead of Delco 36322

Conti 5 PK1345 (CRP K050530)

EDIT: Changed to a Contitech 5 PK1355, the Gates belt was too noisy.

This post has link for Gates catalog (revised Aug2014)

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Wondering if anyone has considered/ pursued this idea.

I did search, but came up empty on anything Fiat related.

Since I have the motor & everything out, now would be the time to explore the possibility :)

Everything I have is Volvo 6-rib style, which maybe a tad heavy for the X1/9.....

I would LOVE to get rid of this mess:

X19-Serp00063.jpg
 
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Keep looking. Someone posted about this in the past year

but for some reason I cannot find that post. So there is a discussion. He posted this picture which I stupidly did not assign an author to.


Anybody remember this?

I think we all agreed that a serpentine belt system would be one of the best things that could ever happen. So much of working on the X is about dealing with these horrible belts, especially on AC cars.
 
Nice!

Wrong style WP for AC cars - but probably could be re-drilled for the AC version? Having the 60-2 wheel would be a nice addition for flexibility with EMS options.

GTTurbo is going to get me some pics of the Punto setup, I'm cheap, if I can use stock parts, I'd rather keep the cost down - if it's practical to do so.
 
GTTurbo is looking into this for me.

I started looking online for 4-rib pulleys - Nissan & Mazda both used them in the mid - late '90's, so maybe some of their stuff could be converted... EDIT: also PT Cruiser
 
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Found a 7 rib serpentine clutch for the Sanden 4508/SD5H14 (thanks LarryC for the info)

Got a 6 rib Denso Alternator pulley coming. Couldn't find a 4 rib Denso. Need pulley that can be modded for the WP, maybe Miata. GTTurbo can get the crank pulley.

Not sure if the rib offset varies as rib # increases - is 4 rib spacing same as 6, 7 rib? I don't know. I can check when the alt pulley arrives.
 
Wow. If you can pull this off in a replicatable package

it will be a great step forward for X-kind. A serpentine belt system would be one mod that even I could go for. What arrangement are you thinking about for a tensioner? Presumably it would need to fit between the water pump and the alternator (?).
 
I would expect the belt manufacturers would have that info buried on their web sites.

Back in the day of paper parts catalogs, this info would be in the "Buyer's Guide" section in the back :)
 
I would shoot for between the alt/WP/AC, so that the belt is wrapped around the alt & WP pulleys as much as possible. I'll work up some legal pad drawings soon.
 
I'll have to see if the service station I sometimes work for has paper catalogs for Dayco or Conti belts - I'll need to figure out what length is going to be required.
 
Design of the bracket to hold it all in alignment

should be fun. The WP and crank are pretty much set. The AC compressor is well-mounted. It seems like the main bracket will be the alternator-tensioner. Something that ties between the AC bracket and the alternator adjustment bracket attachment point would seem like the obvious points of reference.
 
The plan will be to use an auto-tensioner, if possible. Space may not permit. Nissan uses a 4-rib idler pulley, so that could be made to work.

I want the tensioner in between the WP & alt, pushing downward to maximize belt coverage on the WP & Alt pulleys.

This pic is of my Volvo setup - you get the idea as far as % of pulley coverage

XRB5245TBeltRouting2.jpg


Alternate version, closer to older (-98) setup that used an idler in addition. You can see that the crank & AC coverage is not as good, this is the type of thing I want to avoid.

IMG_8288.jpg


So, the plan would be to get similar pulley coverage with the belt routing, preferably with just a tensioner.

I bought a used Miata WP pulley off ebay dimensions are:

OD 5.5"/140 MM, Depth is 26 MM, Center hole is 16 MM, The three mounting holes are 22 MM off center. I'll redrill/space whatever to make it fit offset-wise. It's slightly larger than the AC version, but smaller I believe than the non-AC version.

X19-Serp00074.png


Stock AC WP pulley (Non-AC is 4.5" OD - thank you Thomas * Midwest Bayless)

Approx 4"/101mm OD
IMG_3355_zps0602fcf1.jpg


Approx 1"/24mm depth
IMG_3356_zps9dd877f8.jpg


EDIT (12/18): I think I was looking at a pic I took off the crank pulley when considering the miata WP pulley - this is more than like 1.5" OD larger - I believe than will hit the snail mount, never mind the lower rotating speed..

Sanden (SD5H14) serp clutch will look just like this:

X19Serp00073.png


Complete compressors are not much over $125, but just the clutch assy. can be had for $50, so I'm going that route. Nothing wrong with my compressor, and I don't want to evacuate the system again.
 
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I was fooling around with the belt routing

and it looks like it will be tough to get more than 90 degrees of belt wrap on some of the pulleys. It seems like an idler needs to be in there somewhere. This is just a rough sketch, but shows some of the areas that need resolution.
 
What we need is a pic of the motor with ancillaries mounted - the relationship/spacing is different than your illustration - alt is more inline with WP, and slightly inboard of AC, and WP is further to the right - I believe - which changes how much coverage the WP would see with the tensioner set in that vicinity. Once I get my block into the basement I can start the mockup with alt & WP. AC I will have to gauge- that's still attached to the vehicle.

EDIT: I cannibalized the Punto pic that GTTurbo found for me -

X19Serp00071.jpg


something along those lines, I think
 
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Waiting on WP pulley...

Looking at other options besides the Punto crank pulley, which seems to be very heavy, from comments earlier. Audi/VW use a pressed steel pulley with damper...

X19-Serp00079.png


which butts up against the gear thus:

X19Serp00076.png


So, if the OD, offset & bore are within reason, I may try modding the stock pulley to use as a hub for one of these. Our crank gear is too small OD to drill & install studs for a direct bolt on. Partly depends on shipped cost of Punto pulley. Waiting for some dimensions.

EDIT: OD is 5.6"/142.73, so almost 1" larger OD -

Maybe a Toyota pulley: Listed as 5" OD, 2" depth. Need the ID. I could machine down the back to drop the offset. There are 4 rib single pulley variants, but the ID is almost 6".

X19Serp00075.png


EDIT: The TDS-1ZZFE s 6 rib pulley is 5.4" OD, 2" depth. - would need to machine off the hub down to approx 1/4" or so. Depends on bore size. EDIT: Bore is 25mm, so I should be able to have it re-machined, and a new keyway cut.

X19Serp00060.jpg


Stock Crank Split Pulley (AC)

Shoulder/Bore 40mm/30mm - about 70mm hub if the pulley area is machined off...

X19-Serp00015.jpg


OD approx 4.75-875"/120-124mm
X19-Serp00013.jpg


Depth approx 1.375"/35mm
X19-Serp00014.jpg
 
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These are interesting options

I would have thought that there was something in the Volvo parts bin that was an obvious choice!
Thinking further about the routing of the belt: I have examined a number of serp systems and 1/3 coverage seems to be a standard minimum belt wrap for some larger pulleys. That seems to work for the compressor and even the water pump. Even some power steering pimps on large vehicles use a 25 percent wrap. But with an idler you could get at least 30 percent on most of the pulleys. Something like this using a late model belt layout as a template.

The obvious engineering issue would be the space. But maybe just possible.
 
Volvo pulleys are all 6 rib, and larger.

Yes - option 1 is the direction I would prefer - not much space in there as it is.

Found a Geo Prism/Toyota Corolla WP pulley that may work also - it's small OD - just waiting to get some specific measurements.

EDIT: 4.25" OD, 1.125" ID. Just (hopefully) have to cut off the inner narrow seep section.

X19Serp00077.png


X19-Serp00078.png


GGTurbo is also trying to get me a Fiat WP pulley/cut off shaft, crank pulley and tensioner. Price shipped will have to be a determining factor...

The Miata pulley has the same bolt hole offset - the center could easily be enlarged, but the OD is just too large

IMG_3405_zps87d2f8e7.jpg
 
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