Jump to content

JPM fuel filter vent plugs


frangar

Featured Posts

I'm after 2 fuel filter vent plugs for the JPM duplex filter set up...part no 10-2-89 which seem hard to get. If no one has any it looks like I might be getting some made. They seem to have an odd coarse thread which might just be Whitworth but doesnt seem to quite match my Whitworth thread gauge. They look too coarse to be BSP to my eye. 

 

Ive attached some pictures to see if anyone has any ideas....maybe @steamraiser2?

 

As can be seen the heads are pretty much rounded off hence the need to replace...they just fit a 15mm ring spanner wedged on but that is of course far from ideal.

 

IMG_7864.JPG.769aa60669c47cd5fd1e6921b369b316.JPGIMG_7863.JPG.7240b14268d0d97c224e4819a4e79fd8.JPGimage.jpeg.62610eab7938e28ef20fa432628a2340.jpeg

Edited by frangar
Link to comment
Share on other sites

32 minutes ago, David Mack said:

At 10.39mm it's not Whitworth or BSP, unless it's some non-standard intermediate size.

What is the thread pitch?

 

 

It looks closest to  14 TPI which I think is 7/16" BSW but the diameter measurement is slightly under according to the specs ive found online as you say...but that could just be tolerance I guess. The head of the bolt has a slight chamfer on it too to mate with the top of the filter housing to make a seal but I guess an O ring or fibre/copper washer would also work

 

Here's a pic of my Whitworth thread gauge on it

IMG_7874.jpg.05e9e2fdb22ec56795cd1872cfb34f8c.jpg

Link to comment
Share on other sites

Judging by the way the thread gauge doesn't quite fit I would say slightly less than 14tpi.

 

The thread looks in good condition. If its just the head that is mauled could you file it down to a smaller hexagon (or even square) size to get a good fit to a smaller spanner?

 

Edited by David Mack
  • Greenie 1
Link to comment
Share on other sites

Just now, David Mack said:

Judgiing by the way the thread gauge doesn't quite fit I would say slightly less than 14tpi.

 

The thread looks in good condition. If its just the head that is mauled could you file it down to a smaller hexagon (or even square) size to get a good fit to a smaller spanner?

 

It might come to that as they seem a very odd size...I was hoping it might be easier for a simple replacement!....or get a small batch knocked up to sort me and maybe help others.

 

1 minute ago, Tracy D'arth said:

Could you braze a nut on top to give you a new hex?

Thats another idea I guess if I cant easily source a replacement. 

 

Ive read on one website that the same part number was used on some Lister CS filter housings but again drew a blank finding the actual part anywhere

Link to comment
Share on other sites

It will probably be a metric thread, despite it being on a JP.  Most diesel stuff was originated by Robert Bosch, in Germany and licence produced ( or just copied during WW1) by  CAV et al,  so it was specced in mm.  Fuel injection  pipe is 6mm OD, 2mm bore, the nuts are 19mm with a metric internal thread etc....

 

N

Link to comment
Share on other sites

5 minutes ago, BEngo said:

It will probably be a metric thread, despite it being on a JP.  Most diesel stuff was originated by Robert Bosch, in Germany and licence produced ( or just copied during WW1) by  CAV et al,  so it was specced in mm.  Fuel injection  pipe is 6mm OD, 2mm bore, the nuts are 19mm with a metric internal thread etc....

 

N

i think the duplex filter housing is a Lister engineered part. The rest of the fixings are Whitworth eg the bolts that hold the cover plates for the elements on. Its a pity the manual doesn't list the fixing size for this part as it does some.

Link to comment
Share on other sites

15 minutes ago, Tracy D'arth said:

Could you braze a nut on top to give you a new hex?

 

That would solve the hexagon but the OP says there is a taper at the base of the hexagon section but to me it looks as if there is also a flat that looks as if it has "mushroomed" to form a sharp disk like protrusion. I suspect that bit needs machining and then refitting with something like a Dowty washer.

Link to comment
Share on other sites

I did buy a couple some years ago but can't remember where from. It may have been Sleeman but more likely from Stationary engine parts - they have a mass of files showing stock not listed and was most likely from there. Damned things still didn't seal without resorting to ptfe!

Link to comment
Share on other sites

2 hours ago, frangar said:

i think the duplex filter housing is a Lister engineered part. The rest of the fixings are Whitworth eg the bolts that hold the cover plates for the elements on. Its a pity the manual doesn't list the fixing size for this part as it does some.

I still think this might be a metric thread.  Banjo bolts and bleed screws are common fuel items, so since it is not whitworth  and is  the wrong pitch for  nearby BSP  (G) threads it is  worth  checking imho.

 

Do you have a gauge for 60 deg thread angle?  It does not look to be a 55 deg thread ( ww, bsf, brass)   against your thread gauge, but that is only looking on a phone, and with a pitch that does not match.   Can you put just the end tooth of the gauge onto the thread to see if it matches 55 or not?

 

Also,  2mm pitch is 13.8 tpi, pretty close to the 14 of the not quite right gauge.

 

N

Link to comment
Share on other sites

55 minutes ago, BWM said:

I did buy a couple some years ago but can't remember where from. It may have been Sleeman but more likely from Stationary engine parts - they have a mass of files showing stock not listed and was most likely from there. Damned things still didn't seal without resorting to ptfe!

I’ve tried SEP…but alas no stock of them. I might zip an email to S & H but last I heard they had sold off all their “old stock”…most of which I brought I think! 

53 minutes ago, BEngo said:

I still think this might be a metric thread.  Banjo bolts and bleed screws are common fuel items, so since it is not whitworth  and is  the wrong pitch for  nearby BSP  (G) threads it is  worth  checking imho.

 

Do you have a gauge for 60 deg thread angle?  It does not look to be a 55 deg thread ( ww, bsf, brass)   against your thread gauge, but that is only looking on a phone, and with a pitch that does not match.   Can you put just the end tooth of the gauge onto the thread to see if it matches 55 or not?

 

Also,  2mm pitch is 13.8 tpi, pretty close to the 14 of the not quite right gauge.

 

N

I will have a play but it’s going to be the end of next week now as work is calling. 

Link to comment
Share on other sites

On 06/05/2022 at 11:16, frangar said:

I'm after 2 fuel filter vent plugs for the JPM duplex filter set up...part no 10-2-89 which seem hard to get. If no one has any it looks like I might be getting some made. They seem to have an odd coarse thread which might just be Whitworth but doesnt seem to quite match my Whitworth thread gauge. They look too coarse to be BSP to my eye. 

 

Ive attached some pictures to see if anyone has any ideas....maybe @steamraiser2?

 

As can be seen the heads are pretty much rounded off hence the need to replace...they just fit a 15mm ring spanner wedged on but that is of course far from ideal.

 

IMG_7864.JPG.769aa60669c47cd5fd1e6921b369b316.JPGIMG_7863.JPG.7240b14268d0d97c224e4819a4e79fd8.JPGimage.jpeg.62610eab7938e28ef20fa432628a2340.jpeg

 

On 06/05/2022 at 11:16, frangar said:

I'm after 2 fuel filter vent plugs for the JPM duplex filter set up...part no 10-2-89 which seem hard to get. If no one has any it looks like I might be getting some made. They seem to have an odd coarse thread which might just be Whitworth but doesnt seem to quite match my Whitworth thread gauge. They look too coarse to be BSP to my eye. 

 

Ive attached some pictures to see if anyone has any ideas....maybe @steamraiser2?

 

As can be seen the heads are pretty much rounded off hence the need to replace...they just fit a 15mm ring spanner wedged on but that is of course far from ideal.

 

IMG_7864.JPG.769aa60669c47cd5fd1e6921b369b316.JPGIMG_7863.JPG.7240b14268d0d97c224e4819a4e79fd8.JPGimage.jpeg.62610eab7938e28ef20fa432628a2340.jpeg

 

On 06/05/2022 at 11:16, frangar said:

I'm after 2 fuel filter vent plugs for the JPM duplex filter set up...part no 10-2-89 which seem hard to get. If no one has any it looks like I might be getting some made. They seem to have an odd coarse thread which might just be Whitworth but doesnt seem to quite match my Whitworth thread gauge. They look too coarse to be BSP to my eye. 

 

Ive attached some pictures to see if anyone has any ideas....maybe @steamraiser2?

 

As can be seen the heads are pretty much rounded off hence the need to replace...they just fit a 15mm ring spanner wedged on but that is of course far from ideal.

 

IMG_7864.JPG.769aa60669c47cd5fd1e6921b369b316.JPGIMG_7863.JPG.7240b14268d0d97c224e4819a4e79fd8.JPGimage.jpeg.62610eab7938e28ef20fa432628a2340.jpeg

 

On 06/05/2022 at 11:16, frangar said:

I'm after 2 fuel filter vent plugs for the JPM duplex filter set up...part no 10-2-89 which seem hard to get. If no one has any it looks like I might be getting some made. They seem to have an odd coarse thread which might just be Whitworth but doesnt seem to quite match my Whitworth thread gauge. They look too coarse to be BSP to my eye. 

 

Ive attached some pictures to see if anyone has any ideas....maybe @steamraiser2?

 

As can be seen the heads are pretty much rounded off hence the need to replace...they just fit a 15mm ring spanner wedged on but that is of course far from ideal.

 

IMG_7864.JPG.769aa60669c47cd5fd1e6921b369b316.JPGIMG_7863.JPG.7240b14268d0d97c224e4819a4e79fd8.JPGimage.jpeg.62610eab7938e28ef20fa432628a2340.jpeg

Could you not file the heads down so that a smaller spanner or socket would fit?  As an aside, I may have a complete duplex unit in my lockup if you're interested. I'll need to check.

Link to comment
Share on other sites

Its not generally known ,but CAV and Bosch had a partnership from 1929 to 1938 called CAV-Bosch Ltd to make all the Bosch fuel and electrical stuff in England.......Bosch had lost everything during WW1 ,so it was thought wise to dissolve the partnership in 1938 when war looked likely.....Lucas bought CAV in 1927 .........................forgot to mention ,the plug is 11x2 ,with a taper seat ...no seal  washers or rings.

Edited by john.k
Link to comment
Share on other sites

8 hours ago, monkeyhanger said:

 

 

 

Could you not file the heads down so that a smaller spanner or socket would fit?  As an aside, I may have a complete duplex unit in my lockup if you're interested. I'll need to check.

I might end up getting the file out! Thanks for the offer but I’ve got a complete NOS one squirrelled away but seems daft to salvage just the vent plugs from it….I shall see if I can get some made first. I might use the ones off my new filter as a pattern tho. 

4 hours ago, john.k said:

...forgot to mention ,the plug is 11x2 ,with a taper seat ...no seal  washers or rings.

11 x 2??? 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.