Any experience on aftermarket water pumps?

[OZZY Stewie]

My temp problem is different. Every Saturday it’s cars and coffee, so off we go on an 8 kilometre run to our meeting place.
On the way the engine temp is 170-175. After sitting for roughly 2 hours drinking coffee and talking crap we head home and the engine temp is 140-150 same distance, no hills, no AC and doing 60 kilometres per hour.
Any ideas?
Stewie in OZ

[sseebart]

My temp problem is different. Every Saturday it’s cars and coffee, so off we go on an 8 kilometre run to our meeting place.
On the way the engine temp is 170-175. After sitting for roughly 2 hours drinking coffee and talking crap we head home and the engine temp is 140-150 same distance, no hills, no AC and doing 60 kilometres per hour.
Any ideas?
Stewie in OZ

Strong winds in your locale?

Aside from that, I can only guess that the thermostat doesn't fully open on the drive out, but does during the sit time, which means better flow through the system on the drive back.

~Steve

[dgalietti]

Hi Lee

I see you are a fellow vegas tbird owner. Let me know if you ever need anything!

-David

[Lee Craner]

At the suggestion of jtschug, I purchased an Edelbrock 8805 high volume water pump (and a Milodon 180 degree high volume thermostat). No it didn't cure my running hot at highway speeds, but it did delay it somewhat.

As jtschug mentioned, it takes a bit of modification to get it to fit. I though I'd share my experience.

First, the power steering bracket needed to be ground down just a bit. You can't see it in this picture, but it's right behind the bolt. It was so slight of an interference that I probably could have just forced the issue.

Second, the alternator bracket interfered in two places. The first place is shown here, shown in silver.

At first I started to modify the pump, but decided that too much material would have to be removed, so I modified the bracket by removing a substantial amount of the 1/4" steel plate.

Finally, I removed some of the water pump's casting to finally fit the alternator bracket.

The water pump does work well, but as I mentioned, it still hasn't resolved my hot running engine in the summer heat. So it back to troubleshooting.

[jtschug]

What mix of water to antifreeze are you running in your coolant? Up here in the north we do 50/50 but in hot locations like Vegas you can probably run 75% water and 25% antifreeze. This will improve the heat capacity of the coolant and may help you on the highway when the engine is producing a lot of heat.

Another thing to check is the air to fuel ratio. If you are running more lean, that will cause the engine to make more heat.

[Lee Craner]

Thanks for the ideas, but I believe I'm with/ahead of you. I'm running 60/40 antifreeze/water.

When I received the car last year, it was running about 12:1 air/fuel ratio and spitting a lot of carbon out of the tail pipes. I have it at about 13.5:1 now. No more black soot, but also no change in the running hot.

That said, please keep these suggestions coming.

[Privateer]

I may have missed it - what fan are you running? If it is a clutch type I have seen them be worn where they would "slip" when trying to spin faster (to much air resistance). The clutch part was worn or the fluid partly gone from laying it down instead of keeping it vertical when removed. This caused overheating when driving but not idling. Also does your model have the piece on the underside of the hood to help seal to the radiator? How are the side seals to keep the airflow going through the radiator?
Just some thoughts since you've seem to pretty much eliminate other common issues.

[Phobos]

By all means, im no expert at this.
Just analyzing what seems to be the issue here.

If a car temps up at low speed/idle, it leads to conclusion that the air is not cooling the fluid enough due to low speed.

At high speed, the air cannot be the problem, since the air is flowing rapidly, and the radiator should dispositiv of the excess engine heat easily. The problem must be the transfer of heat to the radiator from the engine, right?

If the engine is rebuilt with clear channels for the coolant, and the waterpump/thermostat is new (and installed correctly- Heard of cases when is was mounted backwards) my next concern would be the radiator not working as it should.

[jtschug]

Just to clarify, when you say 60/40 Antifreeze to water, you mean 60% water, right? Would you consider going up to 75% water?

[jtschug]

Air can be a problem at highway speed even if it isn't a problem at low speed.

At a stop, the engine is idling and making less heat so the system can maintain temperature with less cooling air. The fan provides all the airflow at a stop. Shrouds and seals that prevent the air being sucked by the fan from bypassing the radiator help at a stop.

At highway speed the fan is almost irrelevant (unless the fan is mounted backwards). The engine is making more heat, so it needs more cooling air which is mostly provided by the wind blowing in from the grill. At highway speed the fan shroud actually gets in the way of cooling airflow. Also electric "pusher" fans mounted to the front of the radiator restrict airflow at highway speed which is why you almost never see these on a car from the factory.

Check to make sure there is nothing impeding the flow of air from the grill into the radiator. Also check that there are side seals between the radiator and the body preventing air from "going around" and bypassing the radiator. One trick we used when designing cars when we had a high speed cooling issue was to mount a 1" air dam just below the radiator. You could make one of these pretty easily out of a rigid piece of plastic, and the lower condenser brackets have two holes that provide a nice place to attach it. This creates a high pressure zone in front of the radiator during high speed driving that pushes more air through the radiator passages. Put almost any new car up on a lift and you will see most of them have one (until a parking block rips it off :-)

[jtschug]

As a side note, when I was designing cooling systems for new cars and we had a high speed cooling issue, we started with cardboard and duct tape and we build all kinds of ducts and seals to make sure air coming through the grill had to pass through the radiator. If those made the overheating problem go away, then we would take things away one at a time until we had the minimal thing that still worked, then we designed a duct, seal, and dam package that mimicked the remaining cardboard and duct tape.

[Lee Craner]

Thanks for the hints. I do have the rubber seals on either side of the radiator, but I'll play with the dam idea this weekend.

[Lee Craner]

In my earlier posts, below, I stated that my '65 had issues running hot at speed, but ran fine at idle. After replacing the radiator, putting in a new high capacity water pump and thermostat it still had an issue during our typical hot Las Vegas summers.

Thanks to jtschug and his post, https://www.vintagethunderbirdclub.net/ ... 41#p115741 I can report the issue is now resolved (though his post was last January, I had to wait until our weather heated up to confirm the solution). I simply moved the distributor vacuum advance from the port on the Holley carburetor to manifold. Running hot issue resolved! Thank you jtschug.

[jtschug]

I am glad it is solved. It is always nice to hear when something actually fixed it.