Pulley advice

[NigelDenham]

Hello everyone, my 1600tp has an aftermarket alloy degree’d pulley which I discovered is the smaller diameter. I’ve obtained a later and larger ‘D’ steel pulley. However the alloy one has a polished outer to the stub which goes into a seal in the case. The steel one has a larger diameter “thread” (which I guess is to throw any stray oil back the way it came?). This won’t fit into the seal currently in place……..any comments/ideas?

 

[K@rlos]

Any pics?

 

[NigelDenham]

Any pics?

Hi, sorry, they didn’t load the first time. Hopefully ok now..
by the way, took your recommendation and got an 8 dowel recon std weight flywheel from stateside tuning. Bolted it on today. I’ll update how it feels compared to the lightened one I had when I finally get it back on the road

 

[purpledog07]

Not sure, but from memory i dont recall a seal that the pulley centre goes inside. The thread type groove is to push the oil back into the engine and help it breathe.
Anyone feel free to correct me as its been a while since i worked on these bits.
Some of the popular vendors used to sell a "Sand seal pulley" often used on Bahas and other beach buggys, does anyone know if this had a seal around the pulley to stop dirt ingress?

 

[K@rlos]

Hi, sorry, they didn’t load the first time. Hopefully ok now..
by the way, took your recommendation and got an 8 dowel recon std weight flywheel from stateside tuning. Bolted it on today. I’ll update how it feels compared to the lightened one I had when I finally get it back on the road

That’s ok, from your description and pics it. looks like youve got what they call a sand seal pulley which was designed for desert cars to prevent sand getting pulled into the engine via that oil screw on the standard style pulley (all part of the crank case ventilation system) the case is machined to accept that seal but some rebuilders use it as a way of getting round a worn/damaged case. Your only real option is to look for a decent full size ‘sand seal’ pulley.

Flywheel will definitely be an improvement too

 

[Moseley]

Has your case got a slip-in sand seal added to it? If so, you can carefully remove these, and as long as the case isn’t damaged, an original pulley can then be fitted. I have done the same, the hardest part was removing all the sealant used to hold the sand seal in place without bits dropping into the case!

Photo of behind the pulley would be useful to confirm.

 

[NigelDenham]

Has your case got a slip-in sand seal added to it? If so, you can carefully remove these, and as long as the case isn’t damaged, an original pulley can then be fitted. I have done the same, the hardest part was removing all the sealant used to hold the sand seal in place without bits dropping into the case!

Photo of behind the pulley would be useful to confirm.

Looks like the case hasn’t been machined but an insert has been used, so yeah, maybe I could lever it out. There is also a spacer behind the seal as in the kits I’ve seen online.
so was the sealant used between case and insert?

 

[NigelDenham]

So sounds like I’ve got a sand seal pulley. Could make sense as the engine was built by Kingfisher Kustoms who seem to specialise in buggy’s and off roaders? Everything fitted was more suited to those than a bus I think.
now where do I get a large size pulley for a sand seal?

 

[NigelDenham]

Just looked on their site, looks like this was what’s fitted

https://www.kingfisherkustoms.co.uk/shop/bottom-pulley-with-holes-and-sand-seal/

 

[purpledog07]

What size belt do you have on that?

 

[purpledog07]

The link doesn't mention it's an undersize pulley.

 

[NigelDenham]

The link doesn't mention it's an undersize pulley.

Not really undersize, just the earlier spec on the smaller motors. The guy I got it from had both std pulleys, one from a 1600 and the other he said from a 1300. From what I’ve seen all these aftermarket pulleys seem to be suitable “for all type 1 engines 1200-1600”. The steel ‘D’ pulley is definitely larger diameter. I believe the oem pulleys are 170mm or 178mm (D type) ?

 

[NigelDenham]

I suppose I could machine the steel pulley down to match. I would imagine that’s what the originators of the idea did

 

[purpledog07]

If you have a lathe and the right tooling and skills then it's probably the best option if you want to keep the seal in place. I bet they are a bugger to get out.

 

[purpledog07]

Scat make an alloy pulley at 5 5/8" and another at 6 3/4". The bigger uses same belt as OG on bus type 1 1600tp "AD" engine. What size is yours?

 

[NigelDenham]

Scat make an alloy pulley at 5 5/8" and another at 6 3/4". The bigger uses same belt as OG on bus type 1 1600tp "AD" engine. What size is yours?

The oem pulleys are listed as 6 3/4” or 7”. I’ve just seen CB performance equaliser pulleys in both sizes - expensive though.
I would think the 5 5/8” scat would be a power pulley, that’s really small.
looking at the sand seal kits, it doesn’t look like the cases have to be machined, so maybe I could get the insert out. I think I’ll give kingfisher a call to see what they might have fitted. If not I’ll look at machining the steel original or just stick with the alloy pulley that was on it.

 

[NigelDenham]

If you have a lathe and the right tooling and skills then it's probably the best option if you want to keep the seal in place. I bet they are a bugger to get out.

Yes , I have access to a friends machine shop….used to be a toolmaker

 

[purpledog07]

Belt length will tell you if you would gain anything by changing. Most sand seal kits look pretty much standard stock size. Increasing the pulley size may improve economy slightly but the % really is minimal.

 

[NigelDenham]

Belt length will tell you if you would gain anything by changing. Most sand seal kits look pretty much standard stock size. Increasing the pulley size may improve economy slightly but the % really is minimal.

the belt that was on it is 11.3mm x 912mm- running an alternator.
the main reason I want the larger pulley is for cooling. It had no thermostat and flaps fitted either, so it was taking ages for the oil to warm up properly and then at 60mph I felt it was getting a little hot, which seems to be the reason VW switched to the larger 7” D pulley. There seem to be so many running these aftermarket pulleys (6 3/4”) maybe it’s not an issue.
I’m reinstating the flaps and ‘stat

 

[67panel]

If the case has been line bored it can make the pully opening to large to work well with standard pully and a sand seal repair is only option so proceed with caution