Brass into plastic threads leaking?

[pdub]

Red's intercooler reservoir "tank" is leaking at the brass elbow on the side of it. I thought and said I had it fixed but that ain't so. I've messed with this thing until I'm about ready to cry about it.



I've messed with it to the point where I ordered a new tank from Vortech through Summit. It's on back order from Vortech, maybe ships in a month, and we all know maybe. So I might as well keep messing with this one before I run out of time (Arkansas race at the end of April).

This is brass screwed into gas can plastic and there are lateral vibration forces on it. All we've gathered from research is that brass into plastic is a bad idea according to plumbers. Patrick said it would be okay to use teflon tape on the threads when I asked, which I tried. The water/antifreeze/dye solution in the system dissolves the teflon tape. I suspect it's the UV dye I put in there, that stuff for sure won't wash off of your hands, not ever.

To poll the troops here, what to try next? Before I mess it up permanently. I'm thinking silicone sealant in a squeeze tube. Unit suggested Flex Shot. I/we have no clue. Did I ever say I love Bangshift? If I didn't, I meant to.

Love and thanks,
pdub

[Beagle]

Somewhere on that tank, it may have a recycling symbol like PP or HDPE or PET or PVC or some number in a triangle. It's important to know which one it is if you are going to try a bonding agent (glue) of sorts or try to weld it up. Yes, plastic... you can use the same material it is made of to build it up and re-tap it. You could also consider the same material for the elbow and bond that junk together chemically or mechanically.

Just for background, if that is High Density Polyethylene, there really isn't a glue that will bond it. Heat will allow it to stick to itself and silicone caulk will stick sort of but any stress at all and the silicone will separate.

The other thought I had was use PTFE tape for Gas pipes, the yellow roll. Some are solvent rated.

[squirrel]

The first thing I do when I have a problem with a part, is to carefully disassemble it, then clean and inspect the parts.

It's real easy to crack a plastic fitting by tightening a tapered pipe thread fitting too tight.

[pdub]

Thanks guys, that's the sort of stuff I needed to know. The elbow is "from" the intercooler. There's a straight fitting on the bottom of the tank that goes to the suction on the pump. While I had it apart I put teflon tape on those threads and it's not leaking, never has. I suspect it's in a much more casual setting than the elbow which is hanging on the side and subject to lateral and rotational stress with that hose on it.

I just came home with some silicone sealant and some Flex Shot. THEN I read the fine print, it says not to use the silicone on brass or hard-to-glue plastics.

We're busied up this morning so later this afternoon I'll take it off of the car and take it apart and make note of the recycle symbol and post a better photo. I should have done that before I asked y'all what to think. squirrel, it's not a tapered fitting or at least what I'd call a tapered fitting.

Thanks again guys, more evidence to present later today.

[SuperBuickGuy]

let me do some digging. I put a brass valve on a water jug.... I had the same issues, there is an epoxy that will set that forever. Otherwise, buy an aluminum tank that fits the space... I wouldn't use plastic twice....

[DanStokes]

Here's what I'd try: Assuming you can reach inside the bottle (looks like you can if that round thing is a screw-on cap I'm seeing) buy yourself a bulkhead fitting at your local Parker or Swageloc store. Looks like you'll want it to end up with a 1/4" female pipe thread. The bulkhead fitting will have an O-ring that will seal to the bottle but yu'll have to get a nut started inside the bottle which I think You can do. Snug it up then thread your elbow into the bulkhead w/teflon tape or pipe dope. When you snug up the elbow hold the bulkhead so it doesn't spin. Real fittings from Parker or similar are several steps up from imported hardware store stuff so don't cheap out on this.

Dan

[squirrel]

. squirrel, it's not a tapered fitting or at least what I'd call a tapered fitting.

If it's not a tapered fitting, then you should not need to use any sealer on it. If it has a washer or O ring to seal it, there may be a defect in the plastic or brass, or in the washer or O ring. If it does not have a washer or O ring, then it's probably a tapered thread.

Take it apart, take clear pictures of both pieces, so we can see what you're working on. What you say, doesn't add up.

[pdub]

The other thought I had was use PTFE tape for Gas pipes, the yellow roll. Some are solvent rated.

This looks like Plan A Try #1, thanks to Beags. Fortunately we live just a mile from Home Depot:



I'm all for trying this and having it not work as opposed to smearing some goop on there and waiting a week for it to dry and then seeing that it doesn't work. Meantime, I'll get it offa there later today and post photos. Wow, you guys are GREAT but I knew that already.

[pdub]

buy an aluminum tank that fits the space... I wouldn't use plastic twice....

Neither would I. I saw a fabricated aluminum one yesterday that I might could make fit (imagine me trying to actually fabricate mounts) but it was back ordered for about 6 months. I'll get the photos up and like squirrel said y'all can see what we're working on.

[SuperBuickGuy]

Neither would I. I saw a fabricated aluminum one yesterday that I might could make fit (imagine me trying to actually fabricate mounts) but it was back ordered for about 6 months. I'll get the photos up and like squirrel said y'all can see what we're working on.

I bought a plasma table in the thought of making my own parts.... truth be told, pretty much anything I might make is usually about the cost of material. I strongly suspect that someone makes a tank for your car out of aluminum ....

https://www.steeda.com/mustang-coolant-tanks

https://www.steeda.com/moroso-63530-mustang-supercharger-tank

and if Moroso makes it, guaranteed with a bit more searching, you'll find a chinese knockoff...

[silver_bullet]

Pdub, another idea: when you remove the fitting(s) try to find o-rings that clear the threads, but, seat on the shoulder of the fitting... when you place the fitting back in the tank, the o-ring may seal between the shoulder of the fitting and the tank...

http://www.useloctite.com/downloads/187533_loctite_guide_book_updated.pdf

maybe the above website may help as well....Be sure to check out the last page, they have a toll free number you can call for tech assistance...

[pdub]

SBG as I post this I haven't cruised your links yet, thank you Sir ahead of time. Here we go:


Pic 3, a look inside as best as I could photo it. Dan, I'm having trouble picturing your inside/outside bulkhead solution with this protruding mound on the inside, which is where the threads for the elbow fitting are cut. But I'm having trouble picturing your solution by your description.



The offending leaky elbow removed:

[pdub]

Thank you Patrick, I'll look at that too.

[DanStokes]

The offending leaky elbow removed:

Pdub - That's a NPT - National Pipe Thread. That means tapered pipe.

Dan

[pdub]

Pdub - That's a NPT - National Pipe Thread. That means tapered pipe.

Dan

Cool. I guess? Oh and I forgot, Beags there's not a recycle code on this thing anywhere, not a single where.