Gauge problem or overheating?

[tgshep67]

I have a '65 with a 350 crate motor, haven't had it too long. Whenever I drive it the H20 temp maxes out in just a few minutes, but the car does not seem to be overheating. Anybody have any ideas whether this could be a gauge problem or some sort of compatability problem between this motor and the original gauge? Oh, and I already checked the fluid level It's good!

 

[Ken Anderson]

Probably an incorrect sender.

 

[youwish2bme]

You can get a correct sender from Auto Zone.. TU5 about 8 bucks.. Don't use any thread tape or anything just screw it in to the intake.. Dave..

 

[Ken Anderson]

Actually, Corvette Central & all the other major catalogue companies now stock the correct Delco sender for about 20 bucks.

 

[tgshep67]

Thanks!

Thanks for the info! I will try it out. So great to have all the wisdom out there from other owners! Thanks again!

 

[JohnZ]

Whether you get the Wells TU-5 or the "correctly calibrated" reproduction (which are not, based on the feedback I have so far), borrow or buy an I.R. gun and "shoot" the upper radiator hose just above the thermostat housing and compare that reading vs. the gauge reading at the same time so you know what the gauge is really telling you.

What kind of radiator do you have?

 

[Ken Anderson]

Whether you get the Wells TU-5 or the "correctly calibrated" reproduction (which are not, based on the feedback I have so far), borrow or buy an I.R. gun and "shoot" the upper radiator hose just above the thermostat housing and compare that reading vs. the gauge reading at the same time so you know what the gauge is really telling you.

What kind of radiator do you have?

Have you tried one?

 

[BarryK]

Have you tried one?

I have.
My original sender went out on me last summer and I replaced it with the Wells TU5 unit. It works but reads approx 12-15 degrees hotter than the original sender unit.

 

[Ken Anderson]

No, the new GM resto part.

 

[BarryK]

oops, sorry, I misunderstood.
Nevermind........

 

[JohnZ]

Have you tried one?

Ken, I haven't personally, but two of my Chapter members have, and both still showed 10*-15* hotter than my actual I.R. gun-measured temperature - about the same as the Wells TU-5 and the Standard ST-6 replacements (and the GM #153321 replacements manufactured after 1970) usually show. I now have a Standard ST-6 in my '67, and it's dead nuts accurate - probably dumb luck.

 

[magicv8]

I bagged my original sender and installed a TU5 - it reads about 3-5degrees higher than the original. The IR gun said the original was dead accurate.

 

[Bob Willis]

Crate Motor......What did you use for a water pump ?


Bob

 

[JIMSR]

Same problem

Just my 2cents I had the same problem with my 63 long story short took out thermostat to check it found out it was'nt opening all the way replaced with 160 new one and put and after market temp gage ( from walmart) big spender took car out Sunday temp stayed at 190 in traffic happy camper.
JIM

 

[tgshep67]

Jim--
How did you check the thermostat for opening all the way?
(I know, very rookie question, but we all have to start somewhere)

 

[tgshep67]

Crate Motor......What did you use for a water pump ?


Bob

Bob--
Not sure, I bought it with the engine and all installed. I am just starting to get brave enough to poke around under the hood. I have full documentation so I could probably find out easy enough. Will let you know if I can find the info.

 

[Bob Willis]

Bob--
Not sure, I bought it with the engine and all installed. I am just starting to get brave enough to poke around under the hood. I have full documentation so I could probably find out easy enough. Will let you know if I can find the info.

If you have a newer crate engine in the car ,the water pump may be turning backwards. Newer pumps are driven off of the back of the serpentine belt which makes the pump spin the opposite direction to the older V belt diven pumps. I've seen alot of street rodders chase that one and replace every thing from thermostats to head gaskets.

If the pump came with the engine maybe it's that simple.

Just a thought.
Bob

 

[tgshep67]

Doesn't sound like something easy to fix...

 

[Bob Willis]

Doesn't sound like something easy to fix...

It's not a big deal to change the pump, " if " , that's what is wrong.

The impeller is just turning the wrong way to pump water very well. Then again maybe it's something else, but I would check it before you spent alot of money buying stuff you may not need.

Good luck.

Bob
http://members.kos.net/willisb/

 

[magicv8]

Jim--
How did you check the thermostat for opening all the way?
(I know, very rookie question, but we all have to start somewhere)

I check them by dropping them in a pot of boiling water on the kitchen stove. I try to run the test while my wife is out shopping.:L