help with this POS

[jimmmie '79 Cheyenne]

Got my temp guage working and noticed it's running hot now (little over 1/2 on the guage). It's also puke'n water out the filler with the cap off. It's got a new radiator, w pump, and t-stat (all less than 2 years). I removed the t-stat and the water flows as it should and the temp guage shows about a 1/4. Put back in a new t-stat, (180) after testing it to be sure it was good, and it started puke'n again. I don't think it would be the heads / gaskets or it would be puke'n with the t-stat out. I've read about burping the radiator. Think this is it ??? or is there something else my fried mind is missing. Yea, I am putting the t-stat right - that crossed my mind to. Oh...my ride is not really a pos, if it was I would not have kept it for 27 years...5 years longer than my 1st wife. One or the other had to go...know what I mean?

[jimmmie '79 Cheyenne]

Got my temp guage working and noticed it's running hot now (little over 1/2 on the guage). It's also puke'n water out the filler with the cap off. It's got a new radiator, w pump, and t-stat (all less than 2 years). I removed the t-stat and the water flows as it should and the temp guage shows about a 1/4. Put back in a new t-stat, (180) after testing it to be sure it was good, and it started puke'n again. I don't think it would be the heads / gaskets or it would be puke'n with the t-stat out. I've read about burping the radiator. Think this is it ??? or is there something else my fried mind is missing. Yea, I am putting the t-stat right - that crossed my mind to. Oh...my ride is not really a pos, if it was I would not have kept it for 27 years...5 years longer than my 1st wife. One or the other had to go...know what I mean?

[piecesparts]

Is the T/stat opening all of the way? Try putting another in.

[Bishops Trucks]

Air Bubble? You didn't by chance get a reverse flow waterpump did ya?

[jimmmie '79 Cheyenne]

Reverse flow water pump ??? Never have heard of such a beast. Tell me about it

[piecesparts]

That is a water pump for a later model Chevy engine. This would be an engine that has the serpentine belts, rather than the V-belts like the 62 through87 trucks. On these motors the water pump and the fan rotates in the opposite direction as the ones on our older 350 motors, due to the belt going in the opposite direction.

[hotrodhomi]

it should puke water when you take off the cap, its pressurizes as it heats up. THats what the overflow bottle is for. Are you sure you have a problem?

[MidnightBlues]

hotrodhomi is right. Leave the cap on. Also the perfect working temp for the engine is a little over 1/2 of the gauge (if the gauge is good).
So I think nothing's wrong with your engine.

[Karl Hoh]

Originally Posted by MidnightBlues

hotrodhomi is right. Leave the cap on. Also the perfect working temp for the engine is a little over 1/2 of the gauge (if the gauge is good).
So I think nothing's wrong with your engine.

With everything correct, a 195 t-stat will run 200-205. On the coolant recovery system it will transfer coolant to the overflow bottle when it heats up. Then when it cools down it will suck coolant out of the bottle back into the rad. The rad must be completly full ( right up to the neck ) for this to work properly.

[jimmmie '79 Cheyenne]

Didn't work on it tonite...had to work on my POS computer which I just got back up. Probably wait for Sat. to get back on the truck. Starting it cold with the cap off - it starts puke'n as the needle approaches the 1/2 way mark. The level goes down about 4 inches or so and then pukes. this repeats over and over. The gauge in the past has always read just a little over the 1/4 mark, even when going up the mountains with the ac on (with a 195 stat). It does have a new sending unit now and a different gauge - maybe 1/2 will be the new norm for it. If I can get the radiator to quit puke'n and stay at a constant level I can check the temp with a meat thermometer. Wish me luck ...

[MidnightBlues]

The ONLY way to stop the puking is to stop the engine, Then you can measure the temp of the coolant. But you can also measure the radiator itself. Should be the same temp as the coolant.

[Slonaker]

Originally Posted by jimmmie '79 Cheyenne

The gauge in the past has always read just a little over the 1/4 mark, even when going up the mountains with the ac on (with a 195 stat). It does have a new sending unit now and a different gauge - maybe 1/2 will be the new norm for it.

Are you sure you have the right gauge/sender combination? When I did my engine swap, I used a sending unit for an older ('79 in my '86) pickup because my old one didn't fit the block. It said I was overheating after just a couple of minutes of running. I got an adapter to make the old unit work on the new block, and now everything is fine.

Just a thought...

Slonaker

[jimmmie '79 Cheyenne]

Could be the sender...got it at napa and I've read that they carry two different ones, one for the idiot light and one for a gauge. I don't remember if they asked me if I had gauges or not. Before I discovered my gauge was bad I changed the sending unit. Still have it so I may stick it back in this weekend when I put the t-stat back in. Thanks for the reminder...later