thread sealer on pick up tube?

Do you guys use thread sealer or lock tite on pick up tube threads? 400 block.

I have used gasket shellac

There is a slight taper on the threads so you don't need any sealer.

BS !! ALL pipe threads are tapered - but if you look at any joint done by a pro - gas, water or oil, they use a thread sealant.

The sealant ensures a good seal when you have to back off the fitting for alignment and it also ensures the fitting will stay put.

Go with the sealant. There is a product on the market now called "Pipe Goop". Its clear, will solidify somewhat and is easy to remove if the joint ever has to come apart. Its way less messy than the white pipe sealant.

I use high temp liquid teflon on mine, seems to work good for me

I use liquid teflon pipe dope, sparingly, not dripping

NOT All pipe threads are tapered. There is a standard for straight pipe threads, NPS. I believe the oil pickup tube is NPS.

I ran into this pipe thread overseas. It seems to be more common over there. Sealing a straight thread pipe involves using sealer or something like hemp, turning the pipe into the fitting, then locking it down with a jam nut. This jam nut is supposed to put tension on the joint and get the threads to push against each other, creating a mechanical seal.

http://www.regalcuttingtools.com/products/taps/pipe-taps/straight-pipe-taps/nps-straight-pipe-taps

I would recommend Loctite 567 or 545. They both seal at higher temperatures, 300 and 400F and can be taken apart with hand tools.

R.

ok, thanks guys. I will get some thread sealer then.

The pickup tube is tapered.

Pipe threads that are tapered seal themselves so no pipe SEALER is required on them.

However, pipe lubricant , such as teflon, is required to achieve the recommended torque to seal the pipe. Teflon and other thread lubricants will not seal but will allow proper torque compared to bare threads.

A sealer would be used in straight threads, such as header bolts open to a water jacket, that have no taper and require a sealant to keep them from leaking.

I do have a roll of Teflon tape in the tool box. Guess I'm all set. Thanks

I wouldn't use that. Not to be a naysayer but the risk of that getting into the oiling system is too great for me. I would use liquid teflon or nothing.

NO!

Never used anything, never will.

Indian Head gasket shellac

What did the factory use? They built more engines than we will, and they warrantied them! LOL

Next time I build an engine to factory specs, I'll consider that, but I don't have the budget to replace engines like the factory does.

The factory original pick-up tubes that I have, and had in the past are not tapered, they are straight pipe thread. After market pick-ups seem to be tapered. The threads in the blocks are tapered pipe thread. The threads are designed to seal without sealer but need to have lubricant/sealer to help assure good joint make-up.

I'm wondering why its called "Teflon pipe sealant" instead of "Teflon pipe lubricant".

It can't really go anywhere once the pan is on but you don't want to be sucking air in the threads so I use a little dab of sealer. I use a low strength Loctite blue to do the job but there are probably a bunch of things that will work.

My bad, sealer needed

Its called NPT national pipe thread taper. It is designed to have an interference fit. If it didnt you would bottom out the threads when it was tightened. I have been in engineering for over 35 years. I have seen many motors where there is pipe dope or teflon stuck in the oil pump!!

https://en.wikipedia.org/wiki/National_pipe_thread

ok, I have lock tite thread sealer, gasket shellac as well as blue lock tite on the shelf. looks like I'm good.

That's because the donkey that put it on there put too much on and went right to the end of the threads.

I use red Loctite.

Correct, the factory tubes and the MP replacements are straight pipe thread (measure it for yourself) but the block threads are tapered so there is enough interference fit to allow the pipe to tighten without using a jam nut.

Since a NPT combo is often known to leak, a straight/tapered combo is likely to leak also so a sealer seems prudent.

I suspect that the reason that did the straight into taper is to allow greater adjust-ability at getting the PU in the right orientation without busting the block. You can see that only the first two or so threads are wedged into the thread root in the block.

I learned something new today

I use to get flamed for stating this in past posts. I guess people finally pulled out their calipers.

I think some of you are a little confused, look at the definition of NPT. The taper is actually in the thread angle itself. Its not that the pipe (or hole) gets smaller on the end.The different thread angle is what causes the interference. This would agree with what john said above.
This is from the engineering tool box website.
the angle between the taper and the center axis of the pipe is 1o 47' 24'' (1.7899o)
truncation of roots and crests are flat
60o thread angle
pitch is measured in threads per inch

I'm not confused at all.

I use red loctite too. Maybe it's not needed, but it has never caused a problem for me.

I'm leaning towards the blue loc tite.

the above statement[s] are true. however, for example, a 1/4-18npt thread can be taped using a 7/16" drill for a through hole and get acceptable results. but you will get superior results using a 27/64" drill and a 1/4npt TAPERED reamer, which as the description implies, DOES make a tapered hole. this method is better because it can be used with or without sealer, and assists the 60* thread angle in doing it's job as designed. the practice of using straight through holes was started as a cost saving manufacturing move when it was discovered acceptable [usable] results could be obtained using a non tapered hole for most applications requiring pipe threads. in the above example, the 7/16" drill size is also the required size for a 1/4-18nps[coupling] thread, allowing use of just a common drill without a reamer operation for both types of pipe threads. i also own several common sizes of taper gages used to ensure the proper hole TAPER is obtained before tapping a tapered pipe thread. these gages have a very pronounced [obvious] taper that can be easily seen by the eye. i used this method daily for 42+ years as a machinist tapping 1/8 through 4"npt threads in natural gas metering devices. upon the advent of cnc machining, the tapered reamer was made obsolete in the smaller [1" or less] sizes as it was very easy to bore a tapered hole of the required dimension needed for the larger sizes, and this hole taper was a mandated check for quality purposes.

and if you show one of the younger CNC machinist today a tapered pipe reamer, they look at you and ask what the heck is that for and I tell them back when I was younger doing aerospace machining that was the only acceptable way to thread tapered pipe threads, especially in cast iron and as far as thread sealer,,never seen a plumber yet that didn't use it.