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Old School 327 running hot

Just a thought - it was mentioned earlier that the water pump is supposed to be a long nose / standard rotation impeller design for this application but it might be worth verifying that the vanes are correct; would not be the first time a part was sold incorrectly or mislabeled…
Might help explain the initial variance in temp per side.
Just a thought?
 
tarussell said:
Just a thought - it was mentioned earlier that the water pump is supposed to be a long nose / standard rotation impeller design for this application but it might be worth verifying that the vanes are correct; would not be the first time a part was sold incorrectly or mislabeled…
Might help explain the initial variance in temp per side.
Just a thought?
Click to expand...

I had the same thought, if they bought the pump for a serpentine, but this particular serpentine setup uses std rotation, it could be the wrong pump. However, I would think you would see that in the water flow check he did...?
 
I'd say it's a coolant flow issue. If it's heating up that fast sitting there idling it's not flowing much coolant. Sounds like when it's driving it is flowing a bit since it doesn't immediately cook itself like with a stuck closed thermostat. Could be wrong parts or junk in the cooling system passages.
 
The accessory drive was ordered as a kit with the water pump, p/s pump and compressor. He did give a copy of the receipt and confirmed with CVF that the pump was the correct one for the application.

That’s not to say the wrong pump got tossed in the kit or if the impeller is loose on the shaft and not 100% driven.

Having witnessed somebody who put a standard rotation pump on a stock serpentine drive engine would get hot and stay hot to the point of boiling over quickly.

This one gets up to temp fast but maintains idling. It’s not boiling over fast, nor will it boil over just idling.

We have a Caddy on the rack right now getting an alignment that will finish after lunch and the schedule is open for us to run the tests on the Elky.
 
Well, that was frustrating. I’ll cut to the chase and say this, the engine is building heat quickly enough to open the t-stat inside of 5 minutes. By 20 minutes in the temp on the gauge is creeping up to 220.

Side to side temps checking on the heads were close to each other so I’ll stop focusing on that.

The bright aluminum radiator with its reflective surface throws off the gun readings. But if we read on the hoses leading in we have about a 25 degree drop from the inlet to outlet.

As the temp increased it hit the set temp for the fans and kicked on at 160. During the rest of the test the fans never cycled off. Engine temp crept higher as we went. You can feel the fans moving a good amount of air, driver side is pushing hotter air out of it than the passenger side fan. Though the passenger side of the radiator is cold to the touch on the core.

Shooting the header tubes showed no crazy outlier per side or side to side.

Confirmed values on the intake where both temps sensors are and the values were right on to each other.

Still after 20-25 minutes it was pushing north of 220 on the cluster that proved to be fairly accurate. We shut it off at that point.

We are waiting for the owner to call us back but we want to pull the water pump.

Then we got curious. Started looking at the casting and stamping numbers. Uh-oh, we got a new problem. Casting number is a 3970010 which *could be* for a 1968 327 OR a 1969-1979 350. Prefix on the stamping is TAA which comes back to a 1971 350 out of a truck or van.

That little tidbit may throw the whole 327 overbore theory out the window. But it proves more shady crap that we can’t trust anything that was told to our guy because they fed him some bs. The fact the stamping numbers were still easy to read proved the block wasn’t decked.

We are leaning towards the lack of flow. Though we don’t know if the customer is going to tell the shop that did this to stuff it up their ass and get him what he wanted.

I’m annoyed I didn’t look at the numbers first because I trusted what we were being told as the truth.

Figured why I was out there I’d at least give a visual of the patient. IMG_6169.jpeg
IMG_6170.jpeg
 
I wish GM would have just stamped the engine block like Chrysler did, one look through the fender well and it was obvious what you had…..

This is why I never trust shops to touch anything anymore. Probably sold his 327 to someone and built him an old 350 out of the junkyard with the block all full of shit.
 
To that point, I’m sure there were a lot of “327” engines that were overheating, but they were 350s

Remember, those of you, during the time period after 327s were no longer made, you weren’t cool if you had a 350.

Every engine that left any machine shop was a 327…

Based strictly on empirical data, just people who have told me their engine was a 327 would account for all 110% of all 327s ever built
 
It could still be a 327, 68 was a large journal same as 350, crank rods and pistons, you get a 327. The 68 also used the long water pump and large balancer.
Defiantly sounds like a flow condition, and the water pump is suspect. System holds pressure?
 
Bent77 said:
To that point, I’m sure there were a lot of “327” engines that were overheating, but they were 350s

Remember, those of you, during the time period after 327s were no longer made, you weren’t cool if you had a 350.

Every engine that left any machine shop was a 327…

Based strictly on empirical data, just people who have told me their engine was a 327 would account for all 110% of all 327s ever built
Click to expand...
And usually it was stated that it was a “Vette 327”.
 
Bent77 said:
To that point, I’m sure there were a lot of “327” engines that were overheating, but they were 350s

Remember, those of you, during the time period after 327s were no longer made, you weren’t cool if you had a 350.

Every engine that left any machine shop was a 327…

Based strictly on empirical data, just people who have told me their engine was a 327 would account for all 110% of all 327s ever built
Click to expand...
same phenomena with 66 396 SS Chevelle everyone has one yet only just under 6k were made ?
 
Wes Harden said:
It could still be a 327, 68 was a large journal same as 350, crank rods and pistons, you get a 327. The 68 also used the long water pump and large balancer.
Defiantly sounds like a flow condition, and the water pump is suspect. System holds pressure?
Click to expand...
So the car is a '66

Maybe I read it wrong, but that the original 327 is what was dropped off at the shop
It may be that the engine was changed before this owner, and it isn't

It may be that a 307 crank went into a garbage 350 block, and it's still a "327"
All of those were cast cranks
 
Wes Harden said:
same phenomena with 66 396 SS Chevelle everyone has one yet only just under 6k were made ?
Click to expand...
All of this is part of what I was mentioning earlier. This is like internet lore. While it could be plausible that the 327 blocks overheat, they would have to be borderline from the plant to be that sensitive to an overbore

Never mind every "327" that was rebuilt was not done so back to stock configuration in a stock application.
Oh no, most were higher compression and in some tiny car with a midget and a soda can for a radiator, but it was the blocks fault that all of them overheated.
Then go into used water pumps, 13psi caps, and no glycol. There's little proof of an actual scientific method confirming the block was the problem
Or not some smutz in it
 
I had 2 real 327, 1 small journal and 1 large both were in Chevy II with factory radiators and fixed 4 blade fans, never had overheating issue.
 
Sorta like when you hear someone say "that thing got a cam in it"

Well its a V8 and its running so Id say yes.....

Back on topic......its hard to believe that running at almost 220 degrees the radiator would have a cool spot? Back to flow again. Heating up in 5 minutes makes it seem as though its almost not flowing water at all......that serpentine setup is definitely turning the right way right?
 
ZooMad75 said:
......The bright aluminum radiator with its reflective surface throws off the gun readings. But if we read on the hoses leading in we have about a 25 degree drop from the inlet to outlet.

As the temp increased it hit the set temp for the fans and kicked on at 160. During the rest of the test the fans never cycled off. Engine temp crept higher as we went. You can feel the fans moving a good amount of air, driver side is pushing hotter air out of it than the passenger side fan. Though the passenger side of the radiator is cold to the touch on the core.
Click to expand...
Nice car!

It seems as if the passenger side of the radiator is cold to the touch, it's not getting that coolant into the engine fast enough to cool it down. So either the pump is bad or there is some sort of restriction somewhere.

Chevy305 said:
I'm along for the ride now :popcorn:

Does this fancy pulley system have an under drive or is it stock pulley sizes?
Click to expand...
Based on the pictures it has to be this....

www.cvfracing.com

Black Chevy Small Block Serpentine Conversion - AC & Power Steering, Long Water Pump

Upgrade your engine with the Black Chevy Small Block Serpentine Conversion - AC & Power Steering, Long Water Pump from CVF Racing. Built for performance, precision fit, and classic style.
www.cvfracing.com www.cvfracing.com
 
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