So I permanantly blocked my oil filter bypass

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ME 109
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Re: So I permanantly blocked my oil filter bypass

Post by ME 109 »

Claude, I'm willing to lose the cooler if pressure is an issue.

The Israel motoren distance ring for the remote filter is an interesting setup. I'd like to see the business end of the 'adapter' where it joins the engine case, and see whether it still utilises the oe bypass, or whether the new forward mounted remote filter provides the pressure bypass?

Any oil hoses made would be properly done with correct fittings. It may still be possible to use at least one of the oe cooler lines for the job, if the hose and pipe diametres are suitable.
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robert
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Re: So I permanantly blocked my oil filter bypass

Post by robert »

If oil pressure is an issue there are other coolers up to task. http://www.batinc.net/coolers.htm
These are tested at 170 psi. Should be enough. There may be other sources more accesable to you.
ME 109
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Re: So I permanantly blocked my oil filter bypass

Post by ME 109 »

Thanks Rob, they're good looking units and plenty of sizes. Although a functioning cooler is best practice, I've got away without it working other than manually, for 25 years. When I remember to put the long bolt in for summer, etc.
My remote filter concept using the thermostat will remove the thermostat function, so a tap would be needed for hot/cold weather diversion to the cooler, at least twice a year. There are a few possibilities for plumbing.

I've been having a close look at my thermostat, because it happens to be on my desk under the light. :geek:
I took the thermostat off the bike mainly to check the white oring. It was where it should be, which is good as I've given it some redline with the bypass blocked. I'll check the paper filter for any breaches when I drag it out.

As part of a thorough investigation :geek: into a remote spin on filter, I've studied the thermostat and believe it to be a viable candidate for providing the inlet and outlet for the remote filter. The piston inside the thermostat is needed because it is what separates the oil flow through the thermostat. The piston would need be fixed/held in position with the ports fully open. The orifice sizes throughout the thermostat are mostly equivalent to the size of the drain tube out of the oil filter cavity. I think that means there's no issue with the thermostat taking full oil flow?

The slight clearance of the piston to the the thermostat body may need an appropriate sealant in the right place to prevent oil short cutting the filter. It may not matter either, path of least resistance and all.

If there needs to be oil pressure relief prior to the remote oil filter, that could be done with a bypass valve between the two oil lines. But that's the whole point of the bypass inside the spin on filter, as Wobbly's been pointing out.

Benefit of using the thermostat? I've got it, and should be able to use it without damaging mods.

Now I need the non thermostat cover to look at. :mrgreen:
One thought with this cover is whether banjo bolts will take the full oil flow, because they're made for partial flow.
I'm not sure if there's room for elbows to come off this cover, and not foul the header.
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SteveD
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Re: So I permanantly blocked my oil filter bypass

Post by SteveD »

Sump clearance will be an issue with the spacer/screw in filter. Jeff knows that too. Image
Cheers, Steve
Victoria, S.E.Oz.


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George Ryals
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Re: So I permanantly blocked my oil filter bypass

Post by George Ryals »

Just leave out the thermostat and make a heavy leather cover with a few snaps for the cooler .
The main restriction of oil flow is the main bearing clearances. Since they restrict the flow enough to create a back pressure in the 60 lb range with hot oil, I don't think your remote filter/thermostat system will be a problem in that regard.
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ME 109
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Re: So I permanantly blocked my oil filter bypass

Post by ME 109 »

The thermostat 'function' has to go, in order to use the thermostat body as a permanent two way oil flow setup.
So the cooler air cover would be needed as you suggest George, or some extra plumbing and a tap.

The centre tube in the oil filter cavity extends sufficiently into the thermostat body, including the notched ends.
I've found there is no diversion of oil flow due to the notches. In a functioning cold thermostat, all oil flow goes through the upper section of the thermostat.
If anything, the centre tube fit into the thermostat body is a little loose, and the tube could be remade to achieve a closer tolerance fit to greatly reduce the chance of unfiltered oil leaking past at that point.
The 'loose' fit doesn't matter with a 'normal' thermostat because all the oil is filtered, before it reaches the thermostat.

The 4mm hole in the non thermostat cover would need to be filled, if it's used with a remote filter.

Onwards.
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grant81rs
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Re: So I permanantly blocked my oil filter bypass

Post by grant81rs »

Flames Jeff, that's whats needed mate, that will fix it :)
Cheers, Grant
Gippsland - Australia

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Wobbly
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Re: So I permanantly blocked my oil filter bypass

Post by Wobbly »

Thumbing through the local BMWs for sale in Atlanta today on CraigsList and came across an 80's RT with the oil filter set up as we had discussed. It uses a spin-on filter from a K-bike, and the filter seems to be in series with the cooler.

CraigsList # 6695464717

The filter is remoted to the RH side of the fairing, in place of the RH dual horn. Only one clear photo provided, and it's tiny.

Image

The bike has 70K miles and the owner is some kind of BMW mechanic and has owned the bike for 20 years. Guy's name is Les at (678) 521-6208. You could ask for details and more photos.
After 20 years as a professional bike mechanic and 30 years as an engineer I know just enough to be dangerous !
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Zombie Master
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Re: So I permanantly blocked my oil filter bypass

Post by Zombie Master »

R90SS! What have you wrought!
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ME 109
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Re: So I permanantly blocked my oil filter bypass

Post by ME 109 »

Thanks Wobbly, that's about where I'd mount it. I had a look at the add and didn't see much oil plumbing. He may not even have the cooler plumbed in?

At least I know the bike can run at sustained high revs with the blocked bypass. Clean filter of course.
The need for a remote filter is now to purely allow for easy oil filter change, as well as that nice little bypass function for cold starts.

I agree with gspd that the cooler doesn't want to see full flow or full pressure. I think the cooler feeds need to be an offshoot and return, from the 'filtered oil' return pipe. That theory needs some working out tho.
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