I just installed my extra tank in the box. I put a shut off valve and filter in line so there are a lot of fittings. I have tightened everything just short of breaking or stripping them and I just can't stop the very minor seeping. I used teflon tape on the threads (maybe that is my problem) and tested it with a minimal amount of fuel in the tank. Yesterday I filled it to the top and I guess the increased pressure is causing the seeping. What should I use to stop that. Is there any kind of thread lock or plumbers putty that would work with diesel fuel.
thanks for any replies.

 

To begin with there is a special type of teflon tape for diesel fuel. I had some seepage on a couple of auxiliary tank installs that I did and using the proper type of teflon tape for fuel. There is a liquid form of teflon on the market that I used to cure the problem, it comes in a small white bottle and runs a little under $20.00 here in Nova Scotia.
Take you fittings apart and clean them with brake cleaner, apply a coating of the liquid teflon and tighen, you don't have to over tighten.
That should cure your leaks.

 

Make sure that your fittings you used are the same that are in the tank: ie, Iron pipe, tapered pipe thread, etc. Some of the pipe fittings fit together, but not great. Ive had similar problems. Where is it leaking exactly?

 

I used the tapered pipe fittings on mine with the standard teflon tape and no leaks. Like asked above, are you sure your fittings are the same threads?

 

Thanks for the replies. I will double check the fittings and look for the liquid teflon. I relied on the supplier to give me the right stuff and that may have been a mistake. Thanks a lot for the info.

 

loctite makes a diesel safe thread sealer, cant remember the part number though...(545? maybe)

I bought some high temp loctite sealer at napa, and so far seems fine on my fuel pressure gauge fittings...

 

I think all my fittings are the same. I got them all at the same time from the same source. The one exception is that the in line fuel filter has 1' inlet/outlet and is iron which reduces for the brass 3/8" hose. I am going to get some proper tape or sealant and redo it. I don't know what to do about the iron to brass reduction though. How important is it to not mix different types of metal? (I probably started to use it to soon however with three refineries having their diesel process shut down and a major shortage I was trying to build up a emergency supply on hand)
Thanks.

 

I don't think you'd have any problem with the brass and and iron fittings.