Sealing threads

[Stemar]

I lost my engine last season at a time when I really didn't want to, so I'm fitting twin fuel filters on Jissel, using spin-on filters and 4 taps, so I can run on one filter, but if it clogs, I can switch to the other filter and even change the clogged one while the engine's running.

The filter carriers have 1/4"BSP threads and my fuel taps will screw straight in, but if I just screw them in, the levers are at the backand I'd rather like them at the front, for obvious reasons. Can I use teflon tape and leave them not quite tight, or is there a better way of doing it?

Other parts of the assembly will be screwed down tight, so the taps wouldn't work loose.

 

[pete]

If you have enough thread can you fit slim locking nuts on the thread and lock the tap where you want it with that ?.
Pete

 

[VicS]

You do not say if the threads are tapered or parallel. If tapered extra thicknesses of tape may be the only option but it would be a bit dodgy If parallel then they have to be tightened aginst a joint washer in which case the answer is a thicker washer.

The locking nut idea is not appropriate in either case IMHo as in the former you will need the extra layers of tape anyway and in the latter they won't seal the joint.

 

[alan006]

I've never had much luck with tape for sealing fuel lines. There is a product called Red Hawk which works for petrol or diesel and you smear a little on the joint. A good plumbers merchant should be able to get it for you.
Good luck.

 

[VicS]

[ QUOTE ]
tape for sealing fuel lines

[/ QUOTE ] In fact tape may not be a good idea if there is any risk that little bits of tape could come free and find their way into the injectors!

IMHO thse joints should have parallel threads and tighten onto sealing washers. Annealed copper?

 

[alan006]

I agree that sealing washers are better than tape. Diesel is amazing stuff for weeping through if there is the slightest fault in a joint.

 

[radio]

PTFE tape gets broken down by diesel over a period of time and is not really the best sealant. Suggest you look at a locktite product, these can be a bit costly but are fuel resistant, hydraulic sealer was very good but some others may be better for your application.

 

[sparkie]

Rocol do a liquid PTFE which is supposed to be very good, and enables parallel threads to be sealed without screwing in to the end, but not sure whether it's fuel proof. Have a look at their website, sorry can't do clever links like some folk!

Sparkie

 

[Stemar]

Thanks all - sealant it is, then!

 

[hollandd]

rocol oil seal from plumbers merchants (we use it on fuel lines for oil boilers fueled with kerosene