still running warm

Anders,

In your pic, the water pump pulley appears to be larger in diameter than the crank pulley.

If that is true, then the water pump will turn slower (not faster) that the crankshaft, which will slow the coolant flow.

John

They have the same diameter 5.5

The engine needs a way to circulate coolant when the thermostat is closed, i.e. when starting the engine cold. To disable that would be ill-advised in my opinion.

Compared to older "warm-up" designs that bypass the radiator full time, the Cleveland warm-up system is a very good one. It circulates more coolant during warm-up, and yet no coolant bypasses the radiator when the engine reaches operating temp.

If your Pantera is having over-heating issues, make sure the cooling system has no air, and increase coolant flow at low rpm (smaller pump pulley, Flow Kooler pump, etc).

-G

Flow Kooler X2

To answer your question, SF, if blocked, the engine will take longer to warm up to a stable temperature- but it will eventually reach the same temp either way. That's why early-on, it was thought this made the engine run cooler.

The only advantages to blocking off the coolant bypass is -A- one less place for a water leak, and -B- if blocked off, you can run any type of thermostat, not just the special 351-C assembly. Incidentally, it's better to cap both spigots rather than routing one into the other. The lower spigot is useless in a Pantera since it restricts the adjustment of the alternator during belt changes. I pull it out & use a Loc-tited or JB-Welded freeze plug in the hole.

If the extra spigot's in good shape, keep it around. Those sheet-metal parts rust out and break so it can later be used in the upper position. If you tap the unused boss for a pipe plug, be careful. It's possible to split the pump casting if a pipe fitting is overtightened there. The crack can be TIG-welded if you're lucky. You throw away the pump if you're not....

quote:

still running warm

what's the steady operating temp?

What temp are you running?

+1, what is the gauge reading?

quote:

+1, what is the gauge reading?

What temp gauge sender are you using? Stock from a Pantera?

What temp gauge are you using? Stock Veglia? 230 or 260 range? Aftermarket, and if so, matching sender?

But really, no one has determined WHY you are posing this question.

What observations, other than probably a high temp gauge reading, can you share on the cooling system?

Boiling out the overflow tank on shut down?

Funny noises from behind the firewall?

Point is, we really don't know what you are concerned about or trying to correct.

Details, please .......

Veglia stock gauge and sender. Cooling temp shows the same temp at the gauge and on the computer.

The question is to those how are running clevor or has experience of if the bypass should be used or not and if this will "improve" cooling temp.

Thanks for your ideas
Anders

quote:

Cooling temp shows the same temp at the gauge and on the computer.

And WHAT does it show?

I am still trying to determine IF your engine has a cooling issue at all.

You apparently think there is, but WHAT issues/problems/symptoms are you having?

It is a 408 clevor Fontana 11:1 soon 2000 km, efi solid flat cam .630 lift.
Running between 176 - 194F on high way(today it was 60F out door temp). Stock radiator electric puller fans no air in the cooling system Weiand water pump 160F thermostat. In stop and go traffic it reach 226F. When in idle it seems to not cooling, the temp still rising?!
Anders

quote:

Originally posted by SF:
It is a 408 clevor Fontana 11:1 soon 2000 km, efi solid flat cam .630 lift.
Running between 176 - 194F on high way(today it was 60F out door temp). Stock radiator electric puller fans no air in the cooling system Weiand water pump 160F thermostat. In stop and go traffic it reach 226F. When in idle it seems to not cooling, the temp still rising?!
Anders

First off, 226F in stop and go traffic is excellent. If you were at about 245f then start to get nervous.

Just pressure test the cooling system to verify that it holds 16psi. Check the caps also. You need a pressure tester kit for this.

Your cruising temperatures are actually too low. They should be at just over 212. The 160 thermostat for you is probably too low.

You might want to try the 182 and see it you have a higher cruising temp.

You really need to know what your oil temp is doing in all of this. That temperature MUST GET over 212F in order to boil out the water moisture in the oil.

A GOOD oil temp for normal operation would be something like 220F.

If your oil is too cool, it will cause premature wear on the engine. All the clearances for the bearings, etc, were calculated on the engine operating at the "normal" temperatures. Too cool is BAD. 220F oil is about normal. A little cool actually for that many cubic inches though.

It is possible that your car will not get water temps any higher than what you are showing now at cruising.

That is going to be a function of the cooling capacity of your system. It is telling me that it has a huge cooling system capacity.

I don't think you have an UNDER cooling issue at all. You may be OVER cooling because you expect the operating temps to be lower than you are showing.

That is overreaction to reality.

I would run a oil cooler, cheap insurance and you can buy a on the block unit that sandwiches between the filter and the block use a sender unit with a 180 degree trigger point on sending the oil to the cooler. You will have stabilized water temperature.

quote:

Originally posted by SF:
It is a 408 clevor Fontana 11:1 soon 2000 km, efi solid flat cam .630 lift.
Running between 176 - 194F on high way(today it was 60F out door temp). Stock radiator electric puller fans no air in the cooling system Weiand water pump 160F thermostat. In stop and go traffic it reach 226F. When in idle it seems to not cooling, the temp still rising?!
Anders

It is equipped with an oil cooler and the teperature at yhe gauge shows 230-240F, it has a thermostat- The cooling system is reroted. From water outlet/thermostatic house direct to the radiator. From radiator to the water pump. From the tube between pump an radiator is a pipe welded where a hose is conected to an expansion tank. When I have been using other engines it has never lost any coolant or boiling.

Long ago when the engine and car was stock it sounded like it was making pop corn
Anders

Does the PME remote thermostat with the bypass installed still require a 351c thermostat? How does the bypass shut off once the thermostat is open? If it doesn't, too much coolant will still bypass the radiator and your temp will continue to rise in stop and go traffic. If you are testing the system anyway, try removing the bypass. I've worked on an early PB Pantera with the water restrictor plate plugged running a standard 180 thermostat so there is no bypass and it seems to run well in traffic with a stable temperature running around 180-185 in 85 degree weather. It takes a little longer to warm up so just mind your engine temperature before driving it hard.

I don't like the 1:1 ratio pulleys. The idle flow rate may me okay for a front engined car where the radiator is close but not on a Pantera. But, this is my opinion since there is two schools of thought about coolant flow rate.

Good luck with your troubleshooting.

quote:

Originally posted by LIV1S:
Does the PME remote thermostat with the bypass installed still require a 351c thermostat? How does the bypass shut off once the thermostat is open? If it doesn't, too much coolant will still bypass the radiator and your temp will continue to rise in stop and go traffic. If you are testing the system anyway, try removing the bypass. I've worked on an early PB Pantera with the water restrictor plate plugged running a standard 180 thermostat so there is no bypass and it seems to run well in traffic with a stable temperature running around 180-185 in 85 degree weather. It takes a little longer to warm up so just mind your engine temperature before driving it hard.

I don't like the 1:1 ratio pulleys. The idle flow rate may me okay for a front engined car where the radiator is close but not on a Pantera. But, this is my opinion since there is two schools of thought about coolant flow rate.

The PME house is an "open space", there ix no bypass blocking and it does not reuire a Cleveland thermostat. You could be right, if it continuing feed the pump/engine with hot water. I will test and block the bypass
Good luck with your troubleshooting.

Follow up!

Problem solved (knock on...)

Bad soldered baffle caused bypassing in the tank.

New core, tanks and a good solded baffle.

Running for 2 years now, still good.

Thank you all for good advices!

thanks for the update.

Do you have the original long baffle that separated into front/back or the short baffle that gives upper/lower separation? I have wondered about the effectiveness of a baffle brazed to the tank and just “close” to the core’s tube sheet.

Radiator is the the later one, upper/lower, as mounted from spring -73-