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Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Fri Nov 23, 2012 10:49 pm
by Lewisd
Due to a fuel leak on my carb (The cork jet seals being the culprit) I decided to finally replace them but after removing the jet assembly I found that my Lower jet bearing and Jet adjusting nut are seized together and after attempting multiple methods I can't seem to get them to budge. Has anyone got any tips?

cheers,

Re: Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Fri Nov 23, 2012 11:10 pm
by mike.perry
What carb have you got?

Re: Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Fri Nov 23, 2012 11:19 pm
by bmcecosse
With the cork seals -it's an early H 1 or H 2. Can only suggest applying some heat - a good soak in boiling water perhaps? Failing that - more drastic heating may be necessary.....

Re: Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Fri Nov 23, 2012 11:33 pm
by Lewisd
It's a H2 and I've had a go with boiling water but still no luck :(
I was thinking that possibly freezing followed by boiling water might be my best bet if not, I'll resort to a blow torch and some brute force :/
Cheers,

Re: Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Fri Nov 23, 2012 11:39 pm
by bmcecosse
With freezing - the brass bits may break -take care........ Gentle use of hot air paint stripper - or perhaps a gas torch...... Can you get one part gripped in a vice, and then use a socket on the other ? And of course - a good overnight soaking in Plus Gas or similar (NOT WD 40...) may help.

Re: Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Fri Nov 23, 2012 11:43 pm
by mike.perry
With a diagram in front of you so that you can see where everything fits as you strip it down, remove the pivot pins and the choke lever from the jet.
Remove the suction chamber, piston and needle so that they do not get damaged
Pull the jet out of the carb and the assembly should come apart and you should be able to separate the two nuts before re assembling and testing each component as you go.
A smear of oil on the threads and the outside of the jet should help
Force will only damage the parts

Re: Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Fri Nov 23, 2012 11:46 pm
by Lewisd
Already taken it apart and replaced the seals which has cured the leak but I'm still running too rich due to not being able to adjust the mixture (turing the mixture nut just cause the lower bearing to spin)
cheers,

Re: Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Sat Nov 24, 2012 12:20 am
by mike.perry
I rebuilt an H1 a couple of months ago and as well as the SU Reference Catalogue I had a spare carb stripped down so that I could work out where all the parts went.
The jet sealing nut (j) needs to be screwed tight into the bottom bearing (f), the spring (k) fits between the bottom bearing and the adjusting nut (l).
If the jet assembly still turns after pinching it up a bit tighter, grip it with a spanner whilst you turn the mixture nut until the mixture nut moves freely

Re: Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Sat Nov 24, 2012 10:51 am
by Lewisd
Thanks for the advice.
I will have to have a look tomorrow, Just been looking to see how much a replacement would be if I had no luck or ended up destroying the bolt :oops:
The best I've found is this: http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 1180318019
but obviously thats for the HS2 which I presume would not fit so does anyone know of somewhere I can get one for my H2?
Cheers,

Re: Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Sat Nov 24, 2012 11:21 am
by mogbob
Lewis
Try Burlen.... http://www.burlen.co.uk.They have a very good Technical Helpdesk manned by guys who really know their stuff.
( A satified customer , I used them to buy rebuild kits for a Morris Minor carb and a 1936 Morris Eight Tourer carb).
Bob

Re: Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Sat Nov 24, 2012 12:15 pm
by mike.perry
Burlens will supply service parts for H series carbs, and whilst you are ordering also buy the SU Reference Catalogue, Workshop Manual and Needle Profile Charts

Re: Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Sat Nov 24, 2012 1:21 pm
by Lewisd
Just about to call Burlens but wanted to be able to quote my serial number if needed. Bit of a stupid question but where about on the carb will my serial number be (Its really dirty in my engine bay so perhaps it's just covered in crap :o )
Thanks,

EDIT: found my part number (AUC 6010) apparently from an MG and never used on minors but I've found the correct kit here:
http://www.sucarb.co.uk/ProductDetail.a ... =&Id=24606
Thanks for the advice will get these ordered and hopefully get my carb set up properly :D

Re: Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Sat Nov 24, 2012 4:55 pm
by mogbob
Lewis
Since 1952 the carb Spec number was put on a metal aluminium tag ( triangular ) usually underneath one of the float chamber
screws.What chance, after half a century, of it still being there ?
As Roy has mentioned it's either an H1 type ( up to 1956 according to the SU Reference Catalogue ) and H2 type ( 1957 up to 1959 ).Change to HS2 in 1960/70.
If you check out the Carb sundries kit CSK 001 ( for H type carbs ) it will show you pictures and the part numbers ndividually.
You can then order just what you need.Their Helpline is very helpful if you get stuck.They translate " you know the thin bendy bit of metal, with an offset whats'it" into part numbers !!
Bob

Re: Lower Jet Bearing and Jet Adjusting Nut Stuck!

Posted: Sat Nov 24, 2012 7:42 pm
by bmcecosse
All you need to do is free off the threads! Use plus gas/heat/vinegar/and clamping one part in a vice and turning the other. It's just stuck - it will free off.