Forespar straight threads????

[scherzoja]

Why does Forespar use straight threads on the plumbing parts like their MF 810 Water Strainer and the Marelon tailpipes and hose connectors? Even with teflon tape, rector seal, or Loctite 592, I can't get those fittings to stay put.

My MF 810 has one straight hose barb and one 90 degree elbow hose barb. Often when I bump the hoses (or push it out of the way to get at something) while in the engine compartment, those fittings turn and start to leak. I have to remove them rewrap tape, then retighten. I finally used an o-ring and just screwed the fitting all the way in until they hit the o-ring, but that puts the elbow at a slightly wrong angle.

I wish there were enough thickness in the housing so I could just retap for the next size tapered threads, then use tapered thread fittings. With tapered fittings, I can vary the amount of teflon tap so the threads bind up at the correct angle for the hose to connect without strain.

What is the advantage straight threads over tapered threads on this strainer?

[Manateeman]

Yes. Some of the pipe to hose adaptors are just that, straight thread...we have a lot of valves and pipe to hose adaptors for sale in the forum classified.
The manatee crew.

[stormalong]

Most marine fittings are NPS (national pipe straight). Don't use teflon tape, use caulk. 3M 4200 or 5200. Turn it to the position you want and leave it for a couple of days. Won't turn again.

[scherzoja]

Originally Posted by stormalong

. . . 3M 4200 or 5200. Turn it to the position you want and leave it for a couple of days. . . ..

Thanks.

That was Forespar's advice also, "just use some polyurethane sealant."