Thermostat lodged in water outlet neck - help fix..

[mcintyrederek]

Hi,
350 engine with GM stock iron Qjet intake.  Had to replace the water neck, as I call it, because the old one cracked.  Went to O-Reilly's and got one made of aluminum with two threaded ports in it with plugs.  Looked good to me..  Bought a new gasket as well of course, and while I was at it, a new 180 stat.

It seemed funny to me because the thermostat itself would fit entirely into the opening of the water neck piece.  I wondered as I put it on how the thermostat isn't going to get "sucked up" into the water neck.  Well, it did..

The Qjet iron intake has a machined groove that the t-stat sits in.  Obviously that machined groove is only about a 1/16" recessed groove which keep the stat from dropping into the intake.  The water neck doesn't have such..  Like I said, the opening of the water neck is the SAME SIZE as the diameter of the thermostat.

I put the thermostat in FIRST and then put the gasket in ON TOP of the thermostat, then bolted the water neck down to the intake.  I assumed that possibly the gasket would hold the thermostat in place, and it did for several weeks, until I guess the paper got soft.  So now by taking the radiator hose off and looking into the neck with a flash light, I can see it lodged in there a few inches up and turned sideways.

Do I have the wrong water neck?  I took it back to the parts store and they said all their GM water necks look like this.  I would have checked my old one but threw it away.. of course..  Where can I get a water neck that is a hair smaller than the diameter of the thermostat so it doesn't get sucked up the pipe again?  This has happened twice..  Your thoughts please.

Mack.

[80Chevy4x4]

Ok maybe the thermostat was boxed wrong...it should not fit totally into the water outlet....i would take it back to the parts store and compare to one of the chrome water outlets if they have any...also you can ask them to double check it with another one since companies do make mistakes....in all the years i have had chevy's i have never had that happen.

[enaberif]

Thermostat should sit on the inner ledge. If there is no ledge then your intake is fubarred or crusted up.

Pics would help more.

[bd]

...The Qjet iron intake has a machined groove that the t-stat sits in.  ...I put the thermostat in FIRST and then put the gasket in ON TOP of the thermostat, then bolted the water neck down to the intake.  ...Your thoughts please.

You assembled it correctly.  If the thermostat was of the correct diameter to properly fill the concentric recess in the intake manifold, then the parts store gave you the wrong water outlet - regardless of what their catalog shows - regardless of what the counterman thinks.  The water outlet physically "cages" the thermostat in the recess of the intake manifold to retain it firmly in place.  The gasket is there only to seal against leaks.

[werewolfx13]

I'm going to assume it was a cast aluminum murray water neck...murray plain brown or plain white box parts are COMMONLY misboxed. As in so common, the parts store can order 10 of them, if you're lucky, 5-7 will have the right part in them...1 or two of the ones that dont, will be an empty box with nothing in it at all. What part number did you get? If you can give me a couple days, I'll get one of my stat housings from my shop and take it to work and compare an original to a couple of them, and see if I can find an alternative for you.

[mcintyrederek]

OK..  The thermostat is correct because it sits in a stock GM iron intake.. no problem.  Apparently the water neck is incorrect.  It's a plain aluminum deal like mentioned.  The thermostat sitting in the intake manifold isn't the problem.  It's the water neck is large enough that the thermostat gets sucked into it.  Weather is supposed to be better tomorrow for me here in NC.  I'll pull it apart and take some pics.  I know now I need a different water neck.  I'll post the pics just for reference in case someone else has the same problem. 

While we're at it..  My after market temp gauge is screwed into the head between cylinders 3 and 5..  I'm going to take it that the proper place to measure temperature is right out of the intake just before it goes into the radiator.  Correct?  Should temps be reading slightly cooler measuring at the head itself?

Mack.

[werewolfx13]

The proper location is in the head. Your factory gauge sender is correct.

Did you figure out what part number the housing is? It will be on the box or on the invoice. If nothing else, have the store re-print the invoice you bought it under, as it should be saved under your phone number, assuming they did their job. Alternatively, you may PM me your number, and I'll look it up at work tomorrow. Also, what year truck is this on?

[Stewart G Griffin]

The other thing about the chrome water necks is that they tend to leak based on my, and other's experiences.

Suggest getting one from GM.

[mcintyrederek]

This is on an '86 C10 that originally came with a 4.3 but now has a Goodwrench 350 in it..  The stock iron intake came off an '85 Monte Carlo..  So when I asked for the new water neck outlet, the '85 Monte Carlo was the car I used since the only variant would be the intake.  I figured pretty much all SBC engines with a stock iron intake would use the same outlet.

Mack.

[mcintyrederek]

I had no idea there were two different sizes of water outlets.  I did, indeed, have the wrong size.  See pics.  What is the larger outlet made for?  Is there a larger thermostat size and if so, what does it go in?

Mack..

[HAULIN IT]

I think I'd call that poor aftermarket development. What would be the odds of the inside of that being the same size as the thermostat? Someone who knew nothing about the "workings of" said: "How big does this inside need to be?" & another guy said: "Here, this goes here from what Sui told me...I don't know. It has something to do with a vehicle engine...I'm not sure what it does"

And there is the end result. My Thoughts, Lorne

[LTZ C20]

I think I'd call that poor aftermarket development. What would be the odds of the inside of that being the same size as the thermostat? Someone who knew nothing about the "workings of" said: "How big does this inside need to be?" & another guy said: "Here, this goes here from what Sui told me...I don't know. It has something to do with a vehicle engine...I'm not sure what it does"

And there is the end result. My Thoughts, Lorne

This is probably the best explanation I have heard in a while, hit the nail on the head. It's just crappy product development.

[mcintyrederek]

Well I'm glad I have someone else to share that opinion with.  I'll know next time, which will probably never happen, to take a caliper or at least the old thermostat with me to the parts counter.

Mack.

[werewolfx13]

That larger opening is a stock size for something i've looked up, because the measurement stands out in my head, but I cant remember what its for. Part boxed wrong and your counterman either didnt have one to check, didnt want to take the time to check, or was unlucky enough to get multiple mis-boxed parts of the same part #. Thats not as uncommon as one would think out of Murray.

[Irish_Alley]

i see a difference in the CA emission thermostat housing as the CA are smaller. CA=1.9375 Federal emissions=2.125