G5 CRANKCASE BREATHER OIL LOSS

Information relating to the Matchless G5 or AJS Model 8 350cc Lightweight
Member
User avatar
Posts: 2614
Joined: Wed Dec 14, 2011 1:02 am
Location: ESSEX UK

Re: G5 CRANKCASE BREATHER OIL LOSS

Postby Ozmadman » Sun Jun 02, 2019 10:42 pm

clanger9 wrote:Ah, I just had another thought: you mentioned you've changed the felt oil filter to the earlier mesh type.
However, the later engines have a longer filter to cope with the higher oil pump output. I'm not sure if you can/should mix the early mesh filter with the later crankcase. I guess the early filter it could limit the return flow. Just a thought...
IMG_0215.jpg


Before you dismantle it, I'd double-check it has the correct filter for your crankcases.


The mesh filter for a 350 (as was on mine originally) is the same combined length as the long felt filter/spring assembly.
You do not have the required permissions to view the files attached to this post.
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed

Member
User avatar
Posts: 943
Joined: Sat Jun 20, 2015 8:38 am
Location: Chester, UK

Re: G5 CRANKCASE BREATHER OIL LOSS

Postby clanger9 » Mon Jun 03, 2019 6:56 am

Hi Paul, that's helpful. Did they use the short felt filter at some point, then switch to the longer felt filter?
The mesh filter in your pic looks like it should flow pretty well...
1966 AJS Model 14 250 CSR "cafe racer"
1993 Ducati 750SS

Member
User avatar
Posts: 342
Joined: Sun Mar 18, 2018 12:02 pm
Location: Bristol UK

Re: G5 CRANKCASE BREATHER OIL LOSS

Postby Martin.S » Mon Jun 03, 2019 8:16 am

It does have a very fine brass mesh inside - well mine does any how.

Member
User avatar
Posts: 2614
Joined: Wed Dec 14, 2011 1:02 am
Location: ESSEX UK

Re: G5 CRANKCASE BREATHER OIL LOSS

Postby Ozmadman » Mon Jun 03, 2019 10:08 am

clanger9 wrote:Hi Paul, that's helpful. Did they use the short felt filter at some point, then switch to the longer felt filter?
The mesh filter in your pic looks like it should flow pretty well...
not sure. I changed to the long felt set up as I had a heck of a job getting the mesh one out and had to cut a slot in the cap as the allen key hold was rounded off. When I tried to put it back it would only screw in a few turns then seize up!! and despite many attempts it just wouldn't go and I didn't want to chance damaging the threads in the casing. I would still like to use the original filter and have examined the thread closely but really cant see why it won't screw in. It needs someone better than me to have a look or run a die down it or even weld on a later cap... any ideas?

Thanks Paul
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed

Member
User avatar
Posts: 2649
Joined: Mon Jan 01, 1990 12:00 am
Location: HAMPSHIRE UK

Re: G5 CRANKCASE BREATHER OIL LOSS

Postby ajscomboman » Mon Jun 03, 2019 11:55 am

Ozmadman wrote:
clanger9 wrote:Hi Paul, that's helpful. Did they use the short felt filter at some point, then switch to the longer felt filter?
The mesh filter in your pic looks like it should flow pretty well...
not sure. I changed to the long felt set up as I had a heck of a job getting the mesh one out and had to cut a slot in the cap as the allen key hold was rounded off. When I tried to put it back it would only screw in a few turns then seize up!! and despite many attempts it just wouldn't go and I didn't want to chance damaging the threads in the casing. I would still like to use the original filter and have examined the thread closely but really cant see why it won't screw in. It needs someone better than me to have a look or run a die down it or even weld on a later cap... any ideas?

Thanks Paul


The parts service has some new replacement caps Paul. They're part of some unfinished filters that Andrew Engineering commissioned. We're not planning on making any but will sell the cap to owners who have damaged items, such as yourself. You'll need to find a local company who can silver solder it on (without damaging the chrome) and also remove your old one. Contact me before making any further enquiries as the part is not listed or on the stock shelf, I'll have to sort it out with the staff in advance. Rob

Member
Posts: 1610
Joined: Mon Mar 24, 2014 5:44 pm
Location: Aberdeenshire

Re: G5 CRANKCASE BREATHER OIL LOSS

Postby Mick D » Mon Jun 03, 2019 12:37 pm

Ozmadman wrote: It needs someone better than me to have a look or run a die down it or even weld on a later cap... any ideas?


Hi

Not suggesting I'm any better than you but sometimes a second pair of eyes can help - do you have any good photos of the cap and threads?

Regards Mick

Member
User avatar
Posts: 342
Joined: Sun Mar 18, 2018 12:02 pm
Location: Bristol UK

Re: G5 CRANKCASE BREATHER OIL LOSS

Postby Martin.S » Mon Jun 03, 2019 8:37 pm

I managed to pull the mesh filter off my cap

Mesh Filter.jpg
You do not have the required permissions to view the files attached to this post.
Last edited by Martin.S on Tue Jun 04, 2019 7:09 am, edited 1 time in total.

Member
User avatar
Posts: 2614
Joined: Wed Dec 14, 2011 1:02 am
Location: ESSEX UK

Re: G5 CRANKCASE BREATHER OIL LOSS

Postby Ozmadman » Mon Jun 03, 2019 11:39 pm

Mick D wrote:
Ozmadman wrote: It needs someone better than me to have a look or run a die down it or even weld on a later cap... any ideas?


Hi

Not suggesting I'm any better than you but sometimes a second pair of eyes can help - do you have any good photos of the cap and threads?

Regards Mick
I will fish it out and try to get some close up shots
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed

Previous

Return to G5 / Model 8

Who is online

Users browsing this forum: No registered users and 2 guests