Hose Fit Thermostat

[bobpo1]

I'm about to re-install the in-hose thermostat in my '30 Model A. I know the first time I put it in, it was obviously backwards because I got a lot of back pressure and seepage from under the hose fittings.

Can anyone set me on the proper path here? I know it sounds stupid, but I actually don't remember which I had it in before. It's been out since a heart attack a year or so ago. I also have an in-hose temperature gauge.

Thanks in advance

 

[CarlG]

The "pointy end" goes toward the radiator. Should be as close to the head as possible. The temp probe would go between the t'stat and the head.

 

[AL in NY]

bobpo1: glad to see you're back and feeling better. The thermostat should be placed it the upper radiator hose as close to engine as possible. I would drill a couple of 1/8" holes in it to allow of some water circulation while the engine is warming up. Also, the spring side of the thermostat should face the engine. I would put your temperature gauge in the water neck below the thermostat. With your present in hose temperature gauge, it will most likely be above the thermostat and won't register until the thermostat opens.

 

[bobpo1]

Thanks you guys, makes life so much more pleasant with you folks around. Carl G, I like the "pointy end" reference, that's what some of us old timers need once in a while. Some times things get a little too techinical in this new world. AL, thanks again for your clarification. Tomorrow, I will replace it. I've heard from someone else that there should be some relief holes in the thremo also. I'll do that too.

 

[Quigley1930]

My thermostat has two holes now. Does it need more?

Sewall Tyler

 

[hardtimes]

I'm about to re-install the in-hose thermostat in my '30 Model A. I know the first time I put it in, it was obviously backwards because I got a lot of back pressure and seepage from under the hose fittings.

Can anyone set me on the proper path here? I know it sounds stupid, but I actually don't remember which I had it in before. It's been out since a heart attack a year or so ago. I also have an in-hose temperature gauge.

Thanks in advance

Hey bob,
It is good to hear that you have your heart condition under control...enough to do some repairs on your A thermostat !
Well, my A had a 'heart attack', about six months ago. Hm, first thing that I did, in teardown, was to take the top radiator hose off and remove the thermostat..that you refer to. Hope your stat doesn't have legs , like mine did , as it ran off somewhere in the garage and I haven't found it yet !
I put my 16 yr old wiener dog on to hunting it down, but that didn't work either..bummer. BTW...you using 160 or 180 stat ?

 

[tbirdtbird]

you can put the stat anywhere you want but it will always work its way up to the top of the hose

 

[Mitch//pa]

i cut a lower hose which fits the I.D. of the upper, it holds the stat from moving

 

[A-Jay]

Mitch, others, how much lower hose are you slipping in the upper hose ? are you using a clamp on the stat ? I was running a 160 stat, I had put a second clamp on the stat body at the bottom of the hose. When I removed upper hose to move radiator to remove water pump I found the stat had moved to the top of the hose. What is the problem with the stat sitting at the top other than all the water in the upper hose would need to heat to 160 or 180 before opening. Is the pressure in the hose a issue ? thanks A-Jay

 

[MikeK]

Down and dirty, not as fancy as Mitch//pa and some other guys, I just use a third hose clamp to keep it at the bottom of the hose.

If you look at the 'stat with the short sleeve sold by the vendors, the design is kinda dumb. They put the metal sleeve on the sensor side, holding it up at least an inch from the neck on the head. The metal sleeve should be added on the output (radiator) side. That would permit getting the sensor an inch lower, all the way down into the cast neck.

 

[Tom Wesenberg]

i cut a lower hose which fits the I.D. of the upper, it holds the stat from moving

That's what I did 10 years ago and it worked fine. It did make the top hose very stiff and harder to remove, so when I started having coolant problems due to all the rust flakes, I removed the inner hose and cut off a plastic barbed fitting to hold the thermostat in place. This works equally well and also does not require the third hose clamp.

As Tbird said, if the thermostat isn't held tight, it will work it's way to the top of the hose. I had it happen once on a friend's car. I thought the sleeve on his thermostat had a tight fit in the hose and a hose clamp wouldn't be needed over the stat. I was wrong. After a few miles the stat was at the top.

I also drill two 1/8" holes to allow circulation to warm the stat.

I forgot to add the picture. The nylon sock inside the hose was a filter I tried to trap the rust flakes. It was a failed idea because it filled up and tore loose, then blocked some of the tubes causing the coolant to go out the overflow. I now have a brass screen filter. but won't get a chance to try it until the snow melts.

 

[Mitch//pa]

i cut approx about 1" wide and no need for an unsightly clamp on the outside
as tom mentioned drill some holes

 

[steve s]

My thermostat has two holes now. Does it need more?

Sewall Tyler

Two 1/8" holes are plenty. Of course, they will slow down the warm up time. Modern cars have a bypass that recirculates the coolant thru the motor rather than sending it on to the radiator. Earlier threads showed how some guys have rigged such a deal for a Model A, but it's quite a project.

 

[Quigley1930]

Thank you Steve.

Sewall Tyler

 

[bobpo1]

Thanks again fellas. This keeps gettin' better all the time.

Just built a new Trunk for the coupe and have my first car show May 3rd. Can't wait.

Now if we could just get rid of this snow.......

 

[bobpo1]

Well, I did it right this time and it works like a charm.. Imagine that.

Thanks again fellas.

 

[BILL WILLIAMSON]

If yo' thermo has a sleeve on it, jist poke it in the upper end of the upper hose, HEAT & WATER goes up. Don't need NO extra holes, whin you fire up, COLD, jist rev-er up & look in the filler, you'll be AMAZED at how much flow there is! Some from the tiny vent hole & sum from the valve, which is NOT a perfect seal & also, from the water flow, helping "push" the valve open! KEEP IT SIMPLE & DON'T OVER-ENGINEER IT! OH! & modern thermostats RARELY ever fail.---Bill W.