Fuel Pump Seepage

[Neil Clark]

I've a recurring seepage from the input pipe side of the fuel pump that I thought was fixed but can't seem to eliminate and it's getting worse now that the car is running.    If I buy a new tube nut and olive (TL7 and 060176) is that likely to solve it?  Or should I get the whole inlet connector assembly AHA5535?  And if I fit AHA5535 to the pump, which is the 1964 original, am I just as likely to need a new pump as well because the thread might be worn out?  During the dismantling etc I found that the copper pipe on the inlet side was bent, possibly when the front left wheel was forced back and up in the crash.  I simply straightened the copper pipe near the pump while connected using my hands when putting it all back together and possibly did force it a bit. 

Every time I buy a small part it's costing almost as much as the part in postage etc and I don't have any parts lying around to keep experimenting.

[Colin Lindsay]

Whether or not you need the entire short pipe assembly depends on the condition of your existing pipe; if it's damaged then it won't seal. Similarly with the pump; if the threads into the body are stripped then you might be able to save them by retapping and sometimes even just a new nut works wonders. Take the pump and pipe off and inspect. If it was me I'd go for the new pipe section, new olive and new nut but then when it arrives take the nut off the pipe and test that against the pump threads, just finger tight, to gauge what sort of hold the threads have. It's not gorilla-tight but it does need to be fuel tight. Ultimately leaking fuel isn't something you want round the engine bay so it needs done properly. Pricey maybe but worth it for peace of mind.

[Neil Clark]

Thanks Colin

[Peter Truman]

On the Vitesse I removed the pipe and olive then soldered the olive onto the pipe as the olive had crimped the pipe but wasn’t sealed.

The soldered olive sealed the connection

[Nigel Clark]

Sometimes a couple of turns of PTFE plumbers tape around the olive will help it to seal.

Nigel

[Colin Lindsay]

Not the dreaded PTFE!! I mentioned using it, in the Diff drain plug thread, and had to run for cover....

[Nigel Clark]

5 minutes ago, Colin Lindsay said:

Not the dreaded PTFE!! I mentioned using it, in the Diff drain plug thread, and had to run for cover....

Haha! But it does work.

[Peter Truman]

Which ptfe colour white, pink but I can’t remember where which goes

[Neil Clark]

1 hour ago, Peter Truman said:

On the Vitesse I removed the pipe and olive then soldered the olive onto the pipe as the olive had crimped the pipe but wasn’t sealed.

The soldered olive sealed the connection

But you haven't seen my soldering!

[68vitesse]

I fitted a small o ring on the pipe, pump side of the olive, no trouble since.

Regards

Paul.

[NonMember]

As this is the input side, there's really very little pressure there, so PTFE tape, O-ring, solder the olive, or similar should all be adequate. Unless, of course, your stub pipe is cracked, in which case you need to replace it, as Colin said. They're not usually too propblematic to do, as the brass doesn't generally weld itself to the alloy or corrode straight through it, like some other metals might.

[Neil Clark]

I hope to get some time on Saturday.

[daverclasper]

I have used Blue Hylermar on low pressure connections. Talked to the company and they don't advertise a petrol resistant, though they had done some tests and it implied it could well be?

[Mjit]

On 05/10/2022 at 11:50, Colin Lindsay said:

Not the dreaded PTFE!! I mentioned using it, in the Diff drain plug thread, and had to run for cover....

You should see how people react when someone suggests using it on brake pipe connections!

Had to use some recently while fitting a Chris Witor Wilwood brake upgrade to my big saloon and while googling if it was OK or found one thread where someone savaged another poster for saying "In X case it's fine.", really going for it and how wrong and stupid the previous poster was.  And that would have been fine if it wasn't for the fact they were replying to a post where "X" was "NPT connections" and didn't include "like the Wilwood caliper/brake pipe adaptor connection, in fact here's a link to the Wilwood PDF saying you should ALWAYS use PTFE tape on those connections.".

Always fun when some Internet expert manages to not read the psot they are replying to and so end up saying a major brake manufacturer is wrong about how to use their own products

[Colin Lindsay]

I just couldn't get my head round how plumbers use it to seal threads, but here's ( on a gearbox drain plug) it's a thread lubricant and not a sealer so won't seal minute pits in worn threads.

[Neil Clark]

New nut and olive to the carb seems to have fixed it.

[Stratton Jimmer]

On 05/10/2022 at 13:47, 68vitesse said:

I fitted a small o ring on the pipe, pump side of the olive,

I found one of these on the GT6 which had been fitted by a PO. It does effectively seal the union so I renewed it when I reassembled the pipe / pump joint.

[Clive]

On 06/10/2022 at 12:22, Colin Lindsay said:

I just couldn't get my head round how plumbers use it to seal threads, but here's ( on a gearbox drain plug) it's a thread lubricant and not a sealer so won't seal minute pits in worn threads.

hemp and boss white (which seems to be a fine clay mixed with some sort of oil?)

[68vitesse]

3 hours ago, clive said:

hemp and boss white (which seems to be a fine clay mixed with some sort of oil?)

Try Loctite 55 a more modern alternative.

Regards

Paul 

[Mjit]

On 06/10/2022 at 12:22, Colin Lindsay said:

I just couldn't get my head round how plumbers use it to seal threads, but here's ( on a gearbox drain plug) it's a thread lubricant and not a sealer so won't seal minute pits in worn threads.

Isn't it more a case that everyone uses it as a thread lubricant, just often incorrectly called a sealent - a bit like the 'shock absorbers' in your suspension actually being the springs, not the dampers?

PTFE, or if you prefer trade names Teflon, is just 'smooth and slippy' so lets you tighten a thread more for the same force.  And the tighter the joint's done up the less likely it is to leak/the more likely you'll be able to get past the damaged threads and seal on some clean ones.