Oil Filter assemly

[Fergy65allan]

Urgently need help to find correct oil filter assembly for 1961 G5 Matchless. A picture would be great

regards Fergy65allan

[JimFitz]

Shown in this picture with part numbers http://archives.jampot.dk/book/Workshop ... manual.jpg You can use the enlarge function to see it more clearly.

Regards

Jim

[Ozmadman]

You will need all those part numbers on there if you have nothing at all make sure you use the filter part number listed there with an L suffix as the 350 has a long filter and the 250 a sort filter, should be about 6 and a 1/2" long I think, you swill also need the shorter spring with the longer filter . Here are pics of both set ups

[clanger9]

Just a minor correction, Paul: post-1963, the 250s also used the longer oil filter. Confusingly this also has p/n 042061 (!)

Club spares says the longer 6 1/2" 042061L is for "post 1961 Lightweights". I'm not sure how correct that information is. I think that filter wasn't fitted to 250s until 1963. The filter on my 1966 250 is the same as the upper one in Paul's photos i.e. the longer one.

There's another gauze-type oil filter for Lightweights p/n 042845, but that one is different and I don't think you can get them any more.

Ah, the joys of random Lightweight part numbers...

[Ozmadman]

Just a minor correction, Paul: post-1963, the 250s also used the longer oil filter. Confusingly this also has p/n 042061 (!)

Club spares says the longer 6 1/2" 042061L is for "post 1961 Lightweights". I'm not sure how correct that information is. I think that filter wasn't fitted to 250s until 1963. The filter on my 1966 250 is the same as the upper one in Paul's photos i.e. the longer one.

There's another gauze-type oil filter for Lightweights p/n 042845, but that one is different and I don't think you can get them any more.

Ah, the joys of random Lightweight part numbers...

All confusing but mine (350) is April 1960 and had the original gauze type (pic below)in it. I had a hell of a job getting it out (ended using a large "easy out" which wrecked the allen key hole) as the thread on the cap is must be damaged even though I can't really see much wrong with it visually) This is a long filter. I ended up using all the later stuff using the long felt type. If I can sort the thread out on the original type I would like to use that again

[clanger9]

Yep, I think the longer filter was fitted to the 350s before they fitted it to the 250s. I don't know exactly when, though.

It's also not clear if the longer filter can be retro-fitted. On the one hand, my manual says that the longer filter was introduced along with other (fairly major) changes to the oil system, including a longer stroke oil pump. On the other hand, it also says the longer filter is "particularly beneficial for the 350 engine" (or words to that effect), which suggests that it's a good idea to retro-fit it.

Clear as mud!

[Ozmadman]

Think I had better read the manual as I had no idea there were any mods to the oil/pump system. As far as I can tell there are only one two holes down that oil filter tunnel in the crankcase, 1 right down at the bottom to allow oil through the filter and another nearer the exit in the side of the tunnel for the oil return . All I can presume is the one in the side is in a different position to allow for the long and short filters. Also, at first I was under the impression that the spring allowed for some kind of oil flow should the filter get blocked but in hindsight and considering the almost complete lack of oil pressure these engines create , the spring is just there to keep the filter in position as it is really strong and compressed to its limit when the cap is screwed down so there is no room for movement.

[clanger9]

There's no mention of changes in the engine section of my manual (which is where any sane person would look). However, at the back (p.103) under the title "1963/64 250cc Models", it says this:

IMG_1086.jpg

[Ozmadman]

Thanks, I think the larger crank pin is the one used as standard on the 350 and apparently the flywheels were not circular but had a more triangular profile (check the engine exploded view picture) but I and others I have spoken with have never seen one like it. Also found this.... oil pump specs covering the two different types