Where can I get a 250mm PK7 Pulley?

[Biggles]

I need to get a PK7 pulley or one made that will ideally fit on a Fenner 2012 collett.

 

I did wonder if a different Fenner pulley could be faced off and re-cut with a PK7 profile.

 

Anyone?????

[adrianh]

Hello

Try Transmission Developments in Poole, +44(0)1202 675555 http://www.transdev.co.uk/pages/belts/poly_v/pv_checklist.pdf

The correct name for this type of drive is polyvee belt, they list/manufacture belts and pullies of all types.

You probaly need cast iron for a long life.

A PK7 seems odd, the norm would be PK6 or PK8

 

I obtained a fairly large one from a nissan micra at a breakers yard and adapted this. I run an engineering company so this was easy for me!

 

Come back if you are stuck

[adrianh]

Just another thought on your pulley, if you use a taperlock to mount/drive the pulley you will not get it to run true

This will be a problem if you are mounting something this large, on an engine, to run at a high speed.

Either have it bored and key-wayed when it is manufactured and use a retaining plate/bolt on the end of the shaft, oor, if you have no keyway, use a multi bolt clamp ring from ''Ringfeder' or similar, leaving a good location in the bore tokeep the pulley true.

[Timleech]

Just another thought on your pulley, if you use a taperlock to mount/drive the pulley you will not get it to run true

This will be a problem if you are mounting something this large, on an engine, to run at a high speed.

Either have it bored and key-wayed when it is manufactured and use a retaining plate/bolt on the end of the shaft, oor, if you have no keyway, use a multi bolt clamp ring from ''Ringfeder' or similar, leaving a good location in the bore tokeep the pulley true.

 

If it's to go on that (Deutz) crank that you showed us in a pic, why not get it made to match the existing fitting?

Inertia is another potential issue for some engines, best to keep it as light as possible. If you look at the pic I posted of mine, you'll see that it's bored out to minimise the mass/inertia.

 

I have an alternator which came with a K7 pulley, I worked out that would be OK for my present system but went for 8 rib because belts are a bit easier to find (and nothing wrong with a bit of overcapacity).

 

If you're stuck I could make you one, but probably easier if you find someone closer to home.

 

Tim

Edited April 5, 2013 by Timleech

[Biggles]

Hello

Try Transmission Developments in Poole, +44(0)1202 675555 http://www.transdev.co.uk/pages/belts/poly_v/pv_checklist.pdf

The correct name for this type of drive is polyvee belt, they list/manufacture belts and pullies of all types.

You probaly need cast iron for a long life.

A PK7 seems odd, the norm would be PK6 or PK8

 

I obtained a fairly large one from a nissan micra at a breakers yard and adapted this. I run an engineering company so this was easy for me!

 

Come back if you are stuck

 

How big was the Micra one?

 

If it's to go on that (Deutz) crank that you showed us in a pic, why not get it made to match the existing fitting?

Inertia is another potential issue for some engines, best to keep it as light as possible. If you look at the pic I posted of mine, you'll see that it's bored out to minimise the mass/inertia.

 

I have an alternator which came with a K7 pulley, I worked out that would be OK for my present system but went for 8 rib because belts are a bit easier to find (and nothing wrong with a bit of overcapacity).

 

If you're stuck I could make you one, but probably easier if you find someone closer to home.

 

Tim

 

Hello Tim

 

Yes it it the same. I didn't realise that Automotive pulleys are a different profile to standard power transmission profiles. I was really supprised top fin Fenner didn't have this off the shelf.

 

I will use the existing pulley but will have it modified. I already have a design for this using the Fenner taper lock hub. I did wonder if a different Fenner pulley could have the groves turned off and a new profile cut in to match the PK7. Or if you can make one can you PM me contact details.

[dmr]

Just another thought on your pulley, if you use a taperlock to mount/drive the pulley you will not get it to run true

This will be a problem if you are mounting something this large, on an engine, to run at a high speed.

Either have it bored and key-wayed when it is manufactured and use a retaining plate/bolt on the end of the shaft, oor, if you have no keyway, use a multi bolt clamp ring from ''Ringfeder' or similar, leaving a good location in the bore tokeep the pulley true.

 

Weve got a big one running on a taperlock on our JD3, 330mm or thereabouts.

I think this is the standard Beta installation.

Its been on and off a few times and I have had no problems with it not running true.

Only rev to about 1200rpm.

Used to use some very big ones at work too.

What is the issue with taperlock....is there anything I should be keeping an eye on????

 

.........Dave

[system 4-50]

I love this stuff. I understood the word "the".

[dmr]

I love this stuff. I understood the word "the".

 

But if you did take the time and effort to learn this stuff it would eventually make sense.

Now if we started talking about signature solutions, leverage, and flexible platforms then you would be in trouble because no amount of study will ever reveal what they mean!

 

...........Dave

[BEngo]

But if you did take the time and effort to learn this stuff it would eventually make sense.

Now if we started talking about signature solutions, leverage, and flexible platforms then you would be in trouble because no amount of study will ever reveal what they mean!

 

...........Dave

 

But they all seem to involve taking a helicopter view and thinking out of the box in a blue sky situation at the bleeding edge of the envelope.

N

Edited April 5, 2013 by BEngo

[Grace and Favour]

But they all seem to involve taking a helicopter view and thinking out of the box in a blue sky situation at the bleeding edge of the envelope.

N

 

My envelope has a bleeding edge where I received a paper cut from it this morning

[Biggles]

But they all seem to involve taking a helicopter view and thinking out of the box in a blue sky situation at the bleeding edge of the envelope.

N

 

Funny you mention helicopter. I have trouble with a drive gear on my helicopter as well.

[magnetman]

I just got a quote from Eriks for a 200mm dia PK6 pulley for a 30mm keyed shaft.

 

approx £105- all in

 

I noted that when using a large reduction (over 3:1) with a poly vee belt you can in fact use a flat pulley because the increased wrap will mean the grooves would not be needed.

 

I have bought a 200mm diameter brake drum for a toyota Corolla which I reckon I can adapt to fit the mounting bolts on the flywheel.its solid cast iron and has a flat edge wider than required for the belt. £10.26 from eurocarparts.

 

you could run a pk6 belt on a pk7 pulley as the grooves are the same.

 

what size alternator pulley is it? 250mm drive with a small alt pulley could cause problems you might need an idler specially if the alt is a high output variety.

[Biggles]

The small pulley is 52mm and I have decided the big one should be 235mm. This will give me exactly what I am looking for right across the rev range without overspeeding the alternator.