I drilled and tapped 1/4" npt hole in my cam cover for new pcv system. I have a 1/4" npt to barb screwed in, which will feed to air filter box for breathing in air to the crankcase (this is similar to Dave’s setup)
Problem I have - the cam cover is only 5mm thick, and for clearance with timing chain pulley, i cut the male npt threads to about 5-6mm so its almost flush on the inside. But there is not enough depth for npt taper threads to catch, so it screws in all the way. I can get it nice and tight like this, but i want to put something on the threads to keep it from ever vibrating out, and of course seal well.
I was told blue loctite won’t work on npt threads?
I was told to just use a lot of teflon tape?
I don’t want to use something like JB weld, don’t want it so permanent.
Is there something else i can use? Or should i just put a lock washer on it? Or copper washer?
Of course, nut on other side is out of the question.
The flow of air will be going into this hole. It is providing the inlet for crankcase air. Intake manifold vacuum will be pulling on opposite cam cover.
I can tilt the rubber elbow up so any splash will drain back, when there is no vacuum on crankcase. I may try old fashioned valve cover breather filter so its at atmospheric pressure at full throttle.
I will be measuring, but I’m hoping for 1-2 psi vacuum on crankcase.
I expect more from you. You’ve seen all episodes of the “Friends” tv series, hence you should have more experience with thread types and its applications. The ultra-flow-monster that you’ve installed would be a good for submarine’s diesel cam cover. I assume you’ve got megaPascals of pressure iside your engine - hence NPT thread as a weapon of choice. Just make sure your dip stict wont fly through the back of your head when checking oil level… Just saying.
9/16 UNF has the same pitch, different thread form and is slightly bigger than your ‘ultimate’ choice NPT. Depending on how you’ve “threaded” it so far - it should go in with slight resistance or will require 9/16 UNF tapping. If you don’t have tap (Master of Half-Measures badge) or don’t want to have swarf inside the engine - use 9/16 bolt with some kind of cutting liquid first, them put the adapter in.
…and Greg,
Just don’t… You know what I mean - just ask… Same goes for any PCP rifle that you may have…
Teflon will work just fine Greg.
It will seal without having to tighten the hell out of it and will give some resistance to the threads.
And if you are still worried, I would go with Janusz’s idea.