Oil filter spring length

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
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Richard Hyatt
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Joined: Sun Jan 27, 2019 8:52 pm
Location: Dorset

Oil filter spring length

Post by Richard Hyatt »

Can anyone help with the spring length please.
Our filter is about 5 and 1/2" long but it's a real fight to screw the cap into its thread.
I know the long filter (how long is the long filter please) needs the shorter spring , but just nice to know lengths please.

All this is due to a scavenging problem , without the filter pumps nicely back to the tank , but with the filter in it slows the delivery down dramatically.

We have utterly washed it out and compressed air etc , but I'm wondering if the spring pressure is so strong that it's deforming the filter and bunging things up
cbranni
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Re: Oil filter spring length

Post by cbranni »

I will check lengths tomorrow Richard.

Colin
only dead fish go with the flow
Richard Hyatt
Posts: 113
Joined: Sun Jan 27, 2019 8:52 pm
Location: Dorset

Re: Oil filter spring length

Post by Richard Hyatt »

Thank you
cbranni
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Joined: Sat Oct 09, 2010 9:17 pm
Location: ABERTAWE UK

Re: Oil filter spring length

Post by cbranni »

Right, I have looked in my "lightweight oil" box of bits and can find no springs, they were there but I may have used them for something else. I can only remember one length of spring and that was about 25 to 30mm long.

The filter you have is the short one 142mm the long ones are 163, the filter tunnel is 180 deep so your spring should be about 45 to 50mm long, all the spring does is push the filter down onto an O ring at the bottom of the tunnel which forces the returning oil through the centre of the filter.

Have you checked the tunnel is clear and 180 deep?, below are some photos of the lightweight oil filters from 1958 to 62 the other is 62 on.

Image

Image

This photo I sent to a member a few years ago with the correct spring as I said it looks about 25mm long so yours should be 45 to 50mm

Image

Sorry I was unable to confirm the length of spring you need, but club spares have long filter and spring in stock.

Colin
only dead fish go with the flow
Richard Hyatt
Posts: 113
Joined: Sun Jan 27, 2019 8:52 pm
Location: Dorset

Re: Oil filter spring length

Post by Richard Hyatt »

many thanks Colin

for your considerable trouble and all the info here

well get there in the end , this bike seems to fight us every turn we make !!!!!
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Ozmadman
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Location: ESSEX UK

Re: Oil filter spring length

Post by Ozmadman »

Interesting Colin about the O ring, I don't have that on mine . It isn't shown on the exploded engine diagram but it is mentioned it the older book where it lists the original complete gauze filter. Is it just an o ring as I have hundreds of them in different sizes that I am sure I can utilize.. cheers
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
Richard Hyatt
Posts: 113
Joined: Sun Jan 27, 2019 8:52 pm
Location: Dorset

Re: Oil filter spring length

Post by Richard Hyatt »

As I have the shorter filter , I'm now unsure about my spring length and gauge that I have being correct -I feel that it's way to heavy a gauge looking at yours.
I think the best way forward to have the right combination is a new long filter and its correct spring .
Both of which are available from the club spares
cbranni
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Joined: Sat Oct 09, 2010 9:17 pm
Location: ABERTAWE UK

Re: Oil filter spring length

Post by cbranni »

That sounds a sensible way to go Richard, you then know that part of the system is correct.

Hi Paul, hope you are well, there needs to be a seal at the bottom of the tunnel to force the oil up the middle of the filter then through the filter and back to tank, the seal is listed in spares 58 to 62 and in spares 62 on but not shown in any spares drawing.

The club spares list 042061 filter which is the short one and 042061L which is the long one they also list 042845 which is the original one piece filter but I think that is an error.

It is just an O ring if my memory serves me right, held in place with bit of grease while you push the filter down the tunnel.

Colin
only dead fish go with the flow
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Ozmadman
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Joined: Wed Dec 14, 2011 1:02 am
Location: ESSEX UK

Re: Oil filter spring length

Post by Ozmadman »

Hi Colin, Yes I am well thank you... Better take my filter out and put an o ring down there then!! I have the long filter and short spring but I still have the original gauze one which I would like to use. It was a hell of a job to get out when I first got the bike and I had to cut a slot in the cap as the allen key hole was destroyed. When trying to put it back it would seize up after he first few threads. I have examined the thread on the original filter and cannot see why this is so I ended up using the replacement felt filter parts with a new cap which screws in fine.
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
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