Heater control valve and spigot install

[2wrench]

So do I put any kind of sealant on the heater valve
spigot that screws into the head?

How about sealant between the valve where it screws onto
the spigot?

Recommendations?

Thanks,

 

[Guest]

I always use a little Teflon tape, making sure that you don't overdo it and get some down into the block. One wrap is enough.

 

[RonMacPherson]

Like he said Teflon tape, or the Permatex pipe sealant.

 

[PeterK]

You can also get teflon pipe sealer in a tube (vs. tape).

 

[Brosky]

Do both threads with either, but as Bill said, keep it out of the system.

 

[Aldwyn]

I have found that a couple of wraps of white plumbers tape isn't enough on mine, and it leaks anyway. Your mileage may vary!

 

[PeterK]

Unlike a hex bolt that has parallel threads, pipe threads are tapered. And this taper is what makes the seal.

As you tighten the pipe it moves higher up the (slightly larger in diameter)thread. A little pipe tape or pipe dope (the paste variety of sealer), seals between the irregularities of the threads and the threaded hole. Tighten more and the seal is tighter. So for leaks, just tighten a little bit more and they should stop.

If using tape, wrap in the opposide direction of the thread (usually anti-clockwise.) Otherwise as you tighten the pipe fitting, the tape just twists out of the threads instead of into them.

 

[martx-5]

If using tape, wrap in the opposide direction of the thread (usually anti-clockwise.) Otherwise as you tighten the pipe fitting, the tape just twists out of the threads instead of into them.

Good point. It's always something I have to think about when wrapping threads with the teflon tape. It's sort of counter-intuitive to wrap anti-clockwise.

 

[Inheritr6]

This discussion was perfect timing for me. I just ordered a new heater valve, adaptor, and hoses for my heater. As you can see the PO (my uncle) “modified” the heating system. I actually thought that was stock for quite some time.

 

[Guest]

Actually, that is not a bad fix. The darn aftermarket valves tend to bread (I've lost 2) and the heater control cables break as well. TRF has them on backorder because most of the latest ones they sold were inferior, by their own admission. Trying a new manufacturer.

 

[PeterK]

Looks like yours has a flush-out port with a hose fitting. I think these were provided by the anti-freeze mfgrs to flush the system with a garden hose. My 4A came with a Prestone port.

 

[Inheritr6]

Looks like yours has a flush-out port with a hose fitting. I think these were provided by the anti-freeze mfgrs to flush the system with a garden hose. My 4A came with a Prestone port.

Ahhhhh, I was wondering what that was. I was going to flush my system this weekend, so would you actually hook the hose up to that fitting?

 

[poolboy]

Looks like PeterK is off line right now. So I'll answer. Yes. That's the fitting for flushing that we talked about last night.

 

[poolboy]

I should add that when you unscrew the cap on that fitting, you will probably find male threads on the part still in the heater hose. In my kit there is yet another part, an adaptor/backflow preventor, that leaves you with female threads to hook your garden hose to.

 

[Aldwyn]

Unlike a hex bolt that has parallel threads, pipe threads are tapered. And this taper is what makes the seal.

As you tighten the pipe it moves higher up the (slightly larger in diameter)thread. A little pipe tape or pipe dope (the paste variety of sealer), seals between the irregularities of the threads and the threaded hole. Tighten more and the seal is tighter. So for leaks, just tighten a little bit more and they should stop.

If using tape, wrap in the opposide direction of the thread (usually anti-clockwise.) Otherwise as you tighten the pipe fitting, the tape just twists out of the threads instead of into them.

Mine is tight... 10 grunt tight, at least!

But, you have a point with the tape direction. Never thought of that! I will give that a shot! Thanks!

 

[Geo Hahn]

...I was going to flush my system this weekend, so would you actually hook the hose up to that fitting?

Think about the pressure your cooling systems sees (7 lbs or whatever your rad cap is). Your local water pressure could easily be somewhere in the 65 - 100 lbs range.

This is why you need the adaptor (in addition to the fact that you are presented with male-to-male fittings which is still illegal in some states).

I think the adaptor has some sort of openings and a flappy thing (technical term) to stop backflow and give excessive pressure a way to get out.

 

[Brosky]

Believe George!!!

I have seen heater cores and radiators split wide open at city water pressure. You cannot believe what a mess that will make of your interior in a NY minute with 30+ years of accumulated crud hitting your rugs at 80lbs psi.

 

[poolboy]

You may have to adjust the volume of water at the hose bibb. I like to see a 2 or 3 inch column of water rising out of the radiator fill hole when you back flush the cooling system.
And if you have a radiator shroud, you might want to remove it because the sludge will probably get all over it and it will need cleaning.

 

[TR3driver]

I have seen heater cores and radiators split wide open at city water pressure.

The outlet was just flowing a little bit, but I didn't realize the core was so badly clogged that the inlet was seeing full line pressure ... until it split open.

 

[Inheritr6]

Thanks guys, those are all very good tips. I definitely dont want to mess up my pretty new interior and I just painted my radiator shroud so I’ll be sure to take that off.