V8S petrol tank sender unit

[nawarne]

Help!
Anyone out there got any tips on this?
I've got a slight weep (of petrol) from the sender unit joint on my tank.
I've tried a new gasket/rubber seal - then used 'Hylomar' and now using a German gasket cement called 'Dichstoff' (?) that sets hard.
This last product has reduced the weep from a 'wetness' to a 'dampness'!!! But leaking it is as you still get a whiff of petrol from the wheel arch area.
Anyone with any bright ideas?

[kentishS2]

nawarne said:

Help! Anyone out there got any tips on this? I've got a slight weep (of petrol) from the sender unit joint on my tank. I've tried a new gasket/rubber seal - then used 'Hylomar' and now using a German gasket cement called 'Dichstoff' (?) that sets hard. This last product has reduced the weep from a 'wetness' to a 'dampness'!!! But leaking it is as you still get a whiff of petrol from the wheel arch area. Anyone with any bright ideas?

Hi,

I have the same problem and I used a tank leak sealer repair paste to coat the new sender with and it still weeps. I'm going to cover the whole thing with glass fibre resin soon and hopefully seal it in. It'll be a bit awkward to remove if the sender ever goes again but I'll cross that bridge when I come to it.

[kentishS2]

What is your sender like Nick, is it the one with the screws, or the fixing ring?

Did you use a cork seal or a thick neoprene rubber type?

I found the rubber one was much better and was supplied by the TVR dealer when I bought the new sender unit. But it still leaked!

[WildfireS3]

I replaced mine (ring type) with a rubber seal. Rubber, not neoprene though. No leaks.

[kentishS2]

WildfireS3 said:

I replaced mine (ring type) with a rubber seal. Rubber, not neoprene though. No leaks.

Unlikely to be rubber, the petrol will attack it but it certainly looks like ordinary rubber. I think we probably have the same type, a thick rubber type ring.

My tank has been bodged at some point (probably to stop a leak with a cork gasket). Somebody has fitted screws in the flange of the sender unit instead of using the bayonet ring and the proper rubber type seal. The tank isn't perfectly flat around the hole now and it seems very difficult to achieve a good seal. I can't reinstate the original fitment now because fuel will pour out the holes that a previous owner made to mount it with the screws. Long term, I'll need a new tank but it'll have to wait a while.

[WildfireS3]

If I have to replace mine any time soon, it will have to be a new tank. Someone bent all the flanges on the tank.

[kentishS2]

WildfireS3 said:

If I have to replace mine any time soon, it will have to be a new tank. Someone bent all the flanges on the tank.

Mines been butchered too and I may need a new tank but I may take all mine out and fibreglass around the hole, flat it by sanding carefully and then try and fit a new sender, gasket and locking ring. It's worth a try!

If you do need a new tank, I know a place that makes alloy tanks and myself and Mike V8Smith are going to approach them for a bulk purchase (if we both need one). So, if you fancy joining the numbers for a bit more discount.....

[nawarne]

Guys,
Mine is the type with a neoprene gasket - mounts on the tank flange then the nylon bodied sender unit with these two bits retained by a locking ring that bears down on the sender body and squeezes the joint by a sloping profile on the lock ring.
I guess I could try a new lock ring - maybe the sloping faces have become worn.
Looks like it is not an unheard of problem!!
Thanks for the replies.

[WildfireS3]

I went with New seal and Lock ring. Some people say fitting with 2 seals is good, but I had enough problems with 1!!

KEvin let me know if/when/how much the tank will be. If I still have the car I could well be interested.

[nawarne]

All.
got it sorted at last! I did buy another lock ring and gasket from David Geralds. However, when I was fitting these I noticed that the lock ring tapered face was not 'engaging' with the lowest rolled over tab on the flange on the tank.
A bit of judicious tapping with a centre pop/punch pushed the tabto the centre of the 'hole'. Re-assembled with the German gasket cement and its been bone dry for the last 2 weeks.(Keeping fingers crossed!!!)
I was a bit nervous using steel on steel around the tank in case of sparks. I used a copper mallet to whack the punch though.
Nick

[HarryW]

nawarne said:

All. ...I was a bit nervous using steel on steel around the tank in case of sparks. I used a copper mallet to whack the punch though. Nick

Not as nervous as me when you showed me the leak at Thorney Island in the summer mid fag . I wouldn't have thought you could have described it as a weep then, more like a river . I assume the blue-tack I gave you on the day didn't work then .
Glad its sorted now though.

Harry

[nawarne]

HarryW said:

nawarne said: All. ...I was a bit nervous using steel on steel around the tank in case of sparks. I used a copper mallet to whack the punch though. Nick Not as nervous as me when you showed me the leak at Thorney Island in the summer mid fag . I wouldn't have thought you could have described it as a weep then, more like a river . I assume the blue-tack I gave you on the day didn't work then . Glad its sorted now though. Harry

Harry,
Yeah - was a river then - but this Geerman (scouse accent!) gasket jizz did start to address the problem - if applied in large enough quantity!
However, as mentioned, its amazing how the Mk.1 eyeball can solve a lot of problems!