I have a weeping connection where my needle valve goes into a Tee.  Is there something I can put on the treads to seal that?  It is just enough that if it sits for anytime I have to bump the starter to prime the system?  I have tightened it down as much as I'd like, anymore and something will give.

is the fitting tapered?  

 

I would not recommend putting anything on the threads to someone else, but I have been known to use some yellow thread tape sparenly 

 

The above is not solid advise and I would not do it on someone elses truck.

I use this on just about all my npt fittings, especially after the fuel filter.

it is expensive, but a little goes a long way and it believe it is the safest option for this if you need a thread sealant. I always try to give it 24hrs to cure and it's always worked well :-)

Thank you very much.  Is it pretty common to find?

Unfortunately, no. At least it wasn't for me. I had to order it off amazon. You may be able to find it if you have a good hardware store though. I thought my fastenal would have it because they have a lot of loctite products, but even they would have had to order it and it was way more $ that way than to just order from amazon.

Edited September 9, 20168 yr by leathermaneod

The only thing to keep in mind if you are looking locally is make sure the sealant is rated for diesel use. The regular white thread sealant tape will get eaten up by the fuel. That's why the yellow stuff must be used.

37 minutes ago, Ilikeoldfords said:

The only thing to keep in mind if you are looking locally is make sure the sealant is rated for diesel use. The regular white thread sealant tape will get eaten up by the fuel. That's why the yellow stuff must be used.

what is the yellow stuff?

I think the yellow is diesel rated. It's just a yellow colored thread tape. That's why I use the 545 though. Safe for diesel if I'm not mistaken. Actually, I think Eric at Vulcan even said he uses it. Don't quote me on that, but I believe he and I had a discussion about it. Just look up the specs if your concerned. 

 

Well this is odd, I can't seem to find anything saying the 545 is specifically diesel rated. Though I could have swore Eric said he uses it a lot. Maybe call and ask him if you want? It's for hydraulic and pneumatic applications with high solvent resistance though. It also specifically says it has no fillers or anything to clog small valves or screens so it should be safe for use downstream of the fuel filter anyway. I certainly have no complaints of it on my truck. 

 

http://www.na.henkel-adhesives.com/adhesives/product-search-1554.htm?nodeid=8797921968129

 

http://na.henkel-adhesives.com/product-search-1554.htm?nodeid=8797960011777

 

http://www.akd-tools.gr/xmsAssets/File/TDS/LOCTITE/loctite_545.PDF

 

some reading on it. I still can't seem to find anything that says it's specifically rated for diesel though I could have swore I did before when I decided to use it. Maybe I'm just blind ATM lol you could also look into loctite 542 and see if you can find anything that says it is diesel rated.

 

 

Edited September 9, 20168 yr by leathermaneod

Eric definitely uses it, I've chatted with him about this several times. Fass recommends against using a liquid thread sealant and to use the thread tape. I prefer the liquid type and since Eric gave it such a huge endorsement I got some as well. My local fastenal had it on stock. 

7 minutes ago, notlimah said:

Eric definitely uses it, I've chatted with him about this several times. Fass recommends against using a liquid thread sealant and to use the thread tape. I prefer the liquid type and since Eric gave it such a huge endorsement I got some as well. My local fastenal had it on stock. 

That's what I thought! I don't see why FASS would recommend against it....we are both talking about 545 for sure right? Not some other number?

 

 

all of this said, Richard at GDP told me he uses PTFE white pipe dope and I do have that on the fittings of my fuel boss (that was before I learned about the 545). I don't see an issue using those other sealants (pipe dope or thread tape) before the filter. Not so safe after it, though I have a little loctite 567 I think it is(white goopy stuff), at my fp gauge isolator(again before I knew better). Never had any problems though. Maybe sometime I should take it apart and redo it?

Edited September 9, 20168 yr by leathermaneod

You can use this thread sealer also.

http://www.oreillyauto.com/site/c/detail/PER0/80631.oap?ck=Search_80631_5005221_2902&keyword=80631

I'm sure you could redo it @leathermaneod but if it's holding pressure and not leaking I wouldn't. We're definitely talking about the same stuff! I have a big 50ml bottle of it and I only got it at the recommendation of Eric.