Sump filter on singles

[Keith.owen]

Hi,
Does anyone have any thoughts on this?

I am a bit concerned by the fact that the filter is bolted to the bottom of the crank case, particularly since practically everywhere else where casting are concerned studs are used; this in particular since the filter is removed for cleaning /servicing and needs doing up tight to stop the bolts unthreading. Would it be worthwhile to fit studs and then blots with split washers?

Thanks,

keith

[john.mitchell]

I have done it on a single and a twin. Both because the bolts stripped so I had to retap and use double diameter studs. On the perennially wet sumping twin, I have brazed a nut inside the filter so that the excess oil can be removed by undoing a bolt rather than taking the filter off.

[Keith.owen]

Hi John,
I think I'll fit studs when I remove the filter for the 200 mile oil change.

Keith

[nevhunter]

They are a problem that rocks etc damage the protruding threads and the stud winds out, when you remove the nut Studs can be sealed better than bolts. I have never had a problem with any coming out but if you are worried drill the heads and lock wire them as aircraft do or make a double hole tab washer for the end bolts.( Closer together) Nev

[Keith.owen]

Hi Nev,
Not sure about what you mean by 'studs can be sealed better than bolts'?

Keith

[jj.palmer]

Sump cover repair & mod.pdf

(93.59 KiB) Downloaded 173 times

Hi
I also had the same problem with the sump threads, they were either stripped or very worn I therefore decided to use helicoil inserts and collered bolts as per the sketch. I have always found that sealing studs to be more difficult as the oil leaks down the thread clearance that is between the stud and the nut.
To stiffen the sump cover, which is quite thin I made a stiffening plate to go all the way around the cover also as seen in the sketch.
If you are not to far away Keith I have the equipment to fit you helicoil inserts, it only takes a few minutes.
Regards
John Palmer

[Keith.owen]

Hi John,
It is very kind of you to offer. Fortunately, it hasn't come to having to repair the threads yet - but I am thinking ahead as it were!!

You modification to stiffen the sump filter plate looks interesting; I'm sure mine is dribbling (and always did) so it looks like this could offer a solution!!

I live in Bramley, Hampshire bye the way!!

Keith

[jj.palmer]

Keith
I am quite a way from yourself, Denby Village, Derbyshire, but helicoil inserts kits are quite inexpensive to purchase and they will last you a life time. I purchase mine from Cromwell Tools who have branches all over the UK, you will find them on the internet, price is approx. £25 to £30.
Make sure the stiffening plate is flat or at least the convex side is uppermost to the sump face.
I carried out the mod some time ago and I have had not one drop of oil leak from the sump.

Regards
John

[nevhunter]

Keith, the problem is the threads are through drilled and oil can leak around the threads and has to seal under the head of the bolt by things like a copper washer. A stud can be sealed with things like locktite. Nev

[jj.palmer]

Keith
As an afterthought if you do go down the route of helicoil inserts and you have not done any before have a practice before you attempt the bike. When I first started doing them I practiced on a piece of hard wood "oak" as I had not got a suitable piece of aluminium at the time.
Regards
John