Oil filter set ups... !

[King Rat]

Consternation in the camp.
1988 paralever 80.

XT35 filter came out - so an XT35 filter went back in. There was a shim and a white O ring that came off when I removed the filter... so I put the shim and O ring back in. It worked before, it should work again.

BUT, on the airhead page of Faecesbook... the Yanks are having a dizzy fit about it saying if it has a white o ring, it shouldn't have the shim... filter has fixed rubber ends, not loose ones. There is plenty of 'give' in the rubber ends, there is a gasket on the engine - cover face, so again, more 'give' in the system. Will the shim really make that much difference? Everything has sealed up fine, no oil leaks, oil pressure builds rapidly, since the change the light has gone out immediately. I haven't had the chance to go anywhere, of course, just fired it up in the shed.

Gurus to the fore please... does it matter whether you use a bendy or fixed filter, provided it is the same length? I thought the bedny ones were just for the oil cooler jobbies and simply to make worming it through all the scaffolding easier and not for any internal cavity differences.

 

[clutchspring]

I'm no boxer expert but I to have a 1988 paralever ,when I first changed oil & filter mine was fitted with the exact same as yours ie white Oring, shim,gasget on blanking plate & none bendy filter .never had any problems in the two times I've used this method in 4,000 miles.
Same as you I just put back in what came out with new parts. Some people reckon the shim can cut in to the O ring. I'm shore some guru will be along shortly to confirm right or wrong.��

 

[B Murr]

I think you're right about the bendy, for worming past the oil cooler plumbing or crash bars/frame. My understanding on shim is that it prevents o ring from getting cut and that if you have too much of a recess you can add more.

 

[mikeyboy]

The shim is there to prevent the o ring being forced into the gap between the oil filter tube and the crankcase by oil pressure.if this happens it will dump oil pressure straight into the sump.
Leave it out at your own peril
The yanks call it the $2000 shim

 

[warmshed]

Was this not changed on the later engines 1985 onwards. I believe they finished the end of the tube so it no
longer needs the shim, but no loss if you do use one.

 

[King Rat]

The shim is there to prevent the o ring being forced into the gap between the oil filter tube and the crankcase by oil pressure.if this happens it will dump oil pressure straight into the sump.
Leave it out at your own peril
The yanks call it the $2000 shim

Thank you very much.
I'm glad I put it back together as I found it then - and didn't follow the advice from some of the Yanks! They do try to make a simple thing difficult for some reason.

 

[B Murr]

Was changing gear oil yesterday and a printed version of this article on the o ring issues fell out of my manual. So largaider.com also has a nice few articles on airhead issues but also this one on the o ring. http://largiader.com/tech/filters/canister.html

 

[(RIP) Bin Ridin]

That is a great article, thanks for the link. Great diagram and explanation....