Alternator / Water Pump Belt Specifications?

nigelmercier

nigelmercier

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Live in Kent, boat in Canary Islands
www.bavariayacht.info
My Volvo Penta MD22P-B has a non-standard alternator, but still uses the existing belt: Part: 966912 9.5mm x 975mm

Alternator-Belt_zps3225fc15.png~original


I want to find similar profile belts (preferably Gates) in different lengths, but nobody seems to give this info.

Any ideas?
 
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Nigel

I went to a motor factors in the US they sold me Continental AVX10x975 for a few dollars. Half a mm wider but seems to work fine.
 
These people have been very helpful http://www.viamoto.co.uk/proddetail.php?prod=Gates+V+Belt+-+Fan+Belt+-+6219MC+10mm+x+975mm

You can get various flavours of Gates cogged, long life, extra long life etc. They even do 9.5mm in the extra life versions. You need to keep paging through until you find the right ones but I'm sure that the cheapest 10 x 975 would work.

It's helpful that Volvo use the La measurement for external circumference. I recently replaced the belts on my Yanmars with Gates cogged (MC) belts but Yanmar only quote Li measurements, i.e. internal circumference, so conversion from La to Li is needed. In the end I converted 13 x 925Li into 13 x 1000La which makes them a bit easier to fit when new as the original Yanmars were stinkers!

Richard
 
coopec said:
Are these belts for your Bavaria 47?
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Yes. Initially I want a longer one to move the alternator away from the engine by a few cm. I'm making a turnbuckle adjuster, and it would be better if it could be a bit longer.

Long-term, I'm hoping I can swap the belts, so the 24V alternator and water pump share a belt, and the 12V alternator is alone on a belt: this will give less friction on that belt and a more complete wrap on the pulleys.

Doing the latter depends on whether the bracket that the 12V alternator is mounted on is adjustable fore and aft. From my photographs it looks like it is, but not on the drawing on Marine Parts Europe.
 
nigelmercier said:
Long-term, I'm hoping I can swap the belts, so the 24V alternator and water pump share a belt, and the 12V alternator is alone on a belt: this will give less friction on that belt and a more complete wrap on the pulleys.
.
Click to expand...

I have a Perkins 4-108 and intend installing a 60A 24V and a 120A 12V alternators (Toyota Coaster). I am concerned about the wrap so I thought I would use a serpentine belt (multi "V"). What are yours and OP thoughts?

Can I use automotive air conditioner clutches to switch the alternators "on"and "off"? I figure running both alternators charging flat batteries would take about 8HP
 
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Look for 'Gates Green Line' belts, hard wearing, pre stretched. Been using them for years, replaced originals as they failed and never replaced a Gates.

No connection, just a very happy clint.

Good luck and fair winds. :)
 
I haven't ruled out installing a layshaft to run the alternators as well as a 100L/minute Jabsco pump which I could use as an emergency bilge pump
 
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nigelmercier said:
Thank you. Their catalogue has belt dimensions, which is what I was asking about.
I would love to fit serpentine belts, but have you seen the price of the conversion kits!
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nigelmercier said:
Unfortunately Electromaax don't seem to do a kit for my engine (MD22P-B) and even if they did, what about the alternator pulley? Are these all a standard size?

I'm tempted to see if I can modify a set of pulleys from a car-breaker, especially as I have the added complication of a belt to a second (24V) alternator on the other side. Has anyone tried this?
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Nigel

I'm sure the pulleys would not be a problem at all. You would be able to buy suitable multi "v" pulleys off the shelf and if they didn't fit you could have machined to fit. (not a big deal). The pulley would cost around $A30
(Budget on $A30 for Serpentine belts to fit)

I am using alternators off a Toyota coaster bus but they are in fact Nippondenso alternators. I'm sure I could buy serpentine pulleys to fit Nippondenso alternators.View attachment 41372

Nippondenso Alternators are used by Yanmar Marine (for example) and those alternators look almost identical to my alternators and they use multi-grooved pulleys. Maybe they would fit?

Tensioner pulley are probably around $A40.

Now for the more difficult part. I will have to make up a mounting plate (6mm?) to rigidly fix the alternators as well as the tensioner pulley to. The pulleys on the alternators and tensioner will have to be exactly in-line with the pulley (that may have to be machined) on the crankshaft. The plate would bolt on to the motor where the original mounting points were for the the motor's accessories and a third mounting point could perhaps be an engine mount.

I'm sure it will be a lot easier if I start by making up a ply pattern with all the spacers (to ensure correct alignment.)

Hopefully there are some mechanics posting who could comment on this post
 
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Maybe I don't need to install an automotive air conditioner clutch!! Does anyone know about these?

Multi-V belt kit with freewheel alternator pulley - SKF.com
www.skf.com/au/.../cars/.../multi-v-belt...alternator-pulley/index.html‎
Despite its size, the freewheel alternator pulley plays a vital role in your engine. It absorbs the potentially damaging torque as well as reduces noise and belt ...
 
Nigel

You wouldn't have much trouble finding suitable serpentine pulleys

8 Groove Serpentine Alternator Pulleys
store.alternatorparts.com › ... › Pulleys and Clutch Pulleys‎
Results 1 - 10 of 10 - 8-Groove Alternator Pulley For: Delco 21SI, 25SI, 26SI, 30SI Series Alternators. Used On: Ford Truck, May fit other alternators. Dimensions:


I see what you mean when you say the conversion kits are out of the question

http://www.outbackmarine.com.au/shop/Alternator-Pulley-Conversion-Kits.714
 
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