Mutts Nuts Oversize PV O Rings

[urbantangleweed]

I bought a set of Dave's oversize PV O rings from him recently as the engine I'm building is (like many) exhibiting a little wear in the powervalve tunnels.

He said they need "a good push to get them in, but once in, the bushes won't move or chatter" and he was right, a very good push indeed, but once in, they hold the bushes nice and firmly.

Dave advised to use rubber grease or molyslip but I went with silicone grease as I usually do when fitting PV's.

Anyway, if you've got apparent wear in your PV tunnels, I highly recommend you try a set of these, they're, well, the Mutts Nuts! 

[muttsnuts]

Thanks Roger, I've just finished making a jig so I can now machine the PV barrels so that "oversize" bush housings can be fitted (which I make) and then fit stock size bushes in them, they work a treat

I've got a good few updates to do on the website, this being one of them, but `I'll pop a message on here in due course of all of the new services I offer and prices..... can't move in my workshop for machines and stuff now though !

[urbantangleweed]

Sleeving the PV tunnels (which if I understand correctly is effectively what you will do) is a great idea Dave, I've often looked at them and thought it must be quite possible to machine them and insert an interference fit piece of aluminium tube to eliminate the wear and provide a new surface for the bushes/O rings to sit in.

I look forward to seeing the updated website with all your new stuff added.

[muttsnuts]

Apr 19, 2024 7:04:12 GMT 1 urbantangleweed said:

Sleeving the PV tunnels (which if I understand correctly is effectively what you will do) is a great idea Dave, I've often looked at them and thought it must be quite possible to machine them and insert an interference fit piece of aluminium tube to eliminate the wear and provide a new surface for the bushes/O rings to sit in.

I look forward to seeing the updated website with all your new stuff added.

Hi Roger, no I don't sleeve them, that's what other people have done in the past but it makes the barrels really weak and I've seen a good few crack the exhaust port casting off.

What I do is just machine enough out of the bush housing so that it cleans up, then make an oversize bush housing to fit the new size, then fit the standard size inner phospur bronze bush in side it

[midlifecrisisrd]

Back in the day Stan would machine them and fit a sleeve, had to get it done

Certainly not a lot of meat to get space for a sleeve

Steve

[muttsnuts]

Apr 19, 2024 20:26:56 GMT 1 midlifecrisisrd said:

Back in the day Stan would machine them and fit a sleeve, had to get it done

Certainly not a lot of meat to get space for a sleeve

Steve

yeah, thats why I decided doing what I am doing is better, more faffing, but a better repair and certainly stronger for the barrel