Engine temp rises when I get to cruise speed

[jrvariel48]

Originally Posted by Tinker

Being this is a rebuilt motor. Why would it clogged? I'm sure casting sand was addressed. The only change is the radiator?


I don't know......


I'd suspect the very nice brassworks rad doesn't flow to all the mods you have made. Not really designed for a blower and high flow pumps maybe. I think of them as great solid originals.


One size doesn't fit all. Certainly when you are pushing the limits of a system.


.

The Brassworks radiator was supposed to be built for my blower motor. I know it's 3 core, but that's about all I know technically. It's not an exact 35 replica, but a "street rod" version

[Tinker]

Well... I guess if you have worked it out with them, there might be some more work needed then.


I'm very grateful to them for making a product that we need. Sounds like they are tailoring something specif to you. It'd be hard for me to poop on a company that makes a great product for most over your needs. But I suppose they have to expand their market base as people have to have all the bells.


Hope it works out. I'm just a regular flathead putter.


With all the mods why wouldn't you just go back to the ebay rad? Not like anyone thinks its original? or need the rad core supports to set up the hood.


My guess you are 12v too. It's a track motor in a daily driver. Have fun!

[tubman]

Originally Posted by jrvariel48

I guess the one thing I'm really having trouble understanding is this:

The engine doesn't know MPH, only RPM and load basically.
So if I'm going 30 MPH at 3000 RPM or 60 MPH at 3000 RPM I don't see the difference. I would think that the air movement at 60 MPH would have a better cooling effect than at 30MPH. My A/F numbers are the same when cruising at those speeds. The only time times that changes if when I get on it or take my foot off the pedal. Thanks Ronnie

Again, overheating at highway speeds is usually indicative of a coolant flow problem.

[rich b]

Is it possible your new shroud is restricting airflow at speed?

I've seen openings in shrouds with rubber flaps that open at higher road speed to permit more airflow than fan opening permits.

Seems to me the engine running 3000 at 60 mph would be working harder than engine running 3000 at 30 mph.

[5851a]

Originally Posted by jrvariel48

I believe the Brassworks radiator is copper core

Sorry, I did go back and re read. I always thought brassworks was top notch. Maybe the lower pan could be your answer.

[jrvariel48]

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Originally Posted by Tinker

Well... I guess if you have worked it out with them, there might be some more work needed then.


I'm very grateful to them for making a product that we need. Sounds like they are tailoring something specif to you. It'd be hard for me to poop on a company that makes a great product for most over your needs. But I suppose they have to expand their market base as people have to have all the bells.


Hope it works out. I'm just a regular flathead putter.


With all the mods why wouldn't you just go back to the ebay rad? Not like anyone thinks its original? or need the rad core supports to set up the hood.


My guess you are 12v too. It's a track motor in a daily driver. Have fun!

They knew from the beginning this was a blower motor, it says it on my invoice
While it is a nice piece of craftsmanship, if it don't work, it's useless. I don't want to point to the function of the radiator, but that's what people are saying.
The ebay aluminum radiator looks like absolute crap in my car and I only put it in because I ordered the Brassworks unit.
Yes it's 12 volt
Thanks! Joe

[jrvariel48]

Originally Posted by tubman

Again, overheating at highway speeds is usually indicative of a coolant flow problem.

Tubman I don't doubt what you're saying for a second, but I need a scientific explanation!!! Lol!

Same rpm ,air/fuel mixture, load on motor is all I'm saying

[jrvariel48]

Originally Posted by rich b

Is it possible your new shroud is restricting airflow at speed?

I've seen openings in shrouds with rubber flaps that open at higher road speed to permit more airflow than fan opening permits.

Seems to me the engine running 3000 at 60 mph would be working harder than engine running 3000 at 30 mph.

The grille is original and I cant see how it could restrict airflow being that it will idle for 20 minutes with just the electric fan.

I don't understand how a motor works harder at 60 mph than 30 mph still the same rpm, but that's just me!
Thanks Joe

[Zeke3]

Originally Posted by jrvariel48

I don't understand how a motor works harder at 60 mph than 30 mph still the same rpm, but that's just me!
Thanks Joe

It takes more work to go 60 mph versus 30 mph. Even though your engine speed may be the same at both speeds, due to different gears, going 60 mph will require more torque.

[Ronnieroadster]

Something to consider the load on the engine at 60 MPH is greater than at 30 MPH even at the same RPM. The vacuum reading at 60 will be less than at 30 showing the engine is now under greater load. You really need to determine if the radiator is actually dropping temp entering the engine from what it was leaving the engine.

Ronnieroadster

[jrvariel48]

Originally Posted by Zeke3

It takes more work to go 60 mph versus 30 mph. Even though your engine speed may be the same at both speeds, due to different gears, going 60 mph will require more torque.

Got it! Thanks for the explanation!

[jrvariel48]

Originally Posted by Ronnieroadster

Something to consider the load on the engine at 60 MPH is greater than at 30 MPH even at the same RPM. The vacuum reading at 60 will be less than at 30 showing the engine is now under greater load. You really need to determine if the radiator is actually dropping temp entering the engine from what it was leaving the engine.

Ronnieroadster

Understood. I have a heater hose coming out of the water pump bung. I could install a fitting with the same temp gauge I have in the head.

https://www.amazon.com/Four-Seasons-...29593193&psc=1

[Ronnieroadster]

Originally Posted by jrvariel48

Understood. I have a heater hose coming out of the water pump bung. I could install a fitting with the same temp gauge I have in the head.

https://www.amazon.com/Four-Seasons-...29593193&psc=1

That will work one temp gauge at the head and one at the water pump now you can see what's going on with the radiator core.

[jrvariel48]

Originally Posted by Ronnieroadster

That will work one temp gauge at the head and one at the water pump now you can see what's going on with the radiator core.

Thanks Ronnie, brilliant idea!
When you ran water, did you use anything special or just tap water? Any additive like No-Rosion?
Thanks
Joe

[drolston]

Originally Posted by jrvariel48

I guess the one thing I'm really having trouble understanding is this:

The engine doesn't know MPH, only RPM and load basically.
So if I'm going 30 MPH at 3000 RPM or 60 MPH at 3000 RPM I don't see the difference. I would think that the air movement at 60 MPH would have a better cooling effect than at 30MPH. My A/F numbers are the same when cruising at those speeds. The only time times that changes if when I get on it or take my foot off the pedal. Thanks Ronnie

Stick your hand out the window at 30 mph and you feel the wind drag. Do that at 60 and the drag is no twice as much, it is four times as much, because wind resistance is a function of the square of velocity. So the horsepower required to push that car through the air goes up rapidly with speed. An with the generation of horsepower comes the generation of heat.



At 60, air flow through the radiator is not the problem, it is the cooling capacity of the radiator. Need more frontal area, more fin area, good contact between fins and tubes, clean radiator interior.


I had the both problems, overheating in traffic and at highway speeds. A cute little aluminum radiator rated for 500 horsepower (a lie) would not do the job, but a good clean stock truck radiator finally solved the overheating issues.

[jrvariel48]

Originally Posted by drolston

Stick your hand out the window at 30 mph and you feel the wind drag. Do that at 60 and the drag is no twice as much, it is four times as much, because wind resistance is a function of the square of velocity. So the horsepower required to push that car through the air goes up rapidly with speed. An with the generation of horsepower comes the generation of heat.



At 60, air flow through the radiator is not the problem, it is the cooling capacity of the radiator. Need more frontal area, more fin area, good contact between fins and tubes, clean radiator interior.


I had the both problems, overheating in traffic and at highway speeds. A cute little aluminum radiator rated for 500 horsepower (a lie) would not do the job, but a good clean stock truck radiator finally solved the overheating issues.

Thank you drolston for an excellent explanation!!

[Ronnieroadster]

Originally Posted by jrvariel48

Thanks Ronnie, brilliant idea!
When you ran water, did you use anything special or just tap water? Any additive like No-Rosion?
Thanks
Joe

I used tap water and added water pump lube when I could find it at the local parts stores.
Ronnieroadster

[jrvariel48]

Originally Posted by Ronnieroadster

I used tap water and added water pump lube when I could find it at the local parts stores.
Ronnieroadster

Thanks Ronnie. I spoke with Lee from Brassworks and he thinks the two temp gauge method you incorporated into your cooling system is a great idea. He said it will tell you if the radiator is cooling the antifreeze or not.

He also asked for pictures for the shroud on my puller because he thinks that could be a potential problem. It may actually be slowing the air down. This is why they use reliefs in their shrouds.
I'll be able to get the supply temp gauge in this weekend if all the parts come in time.
I'll post the results if that happens.
Thanks Joe

[Bored&Stroked]

Something that I'd try is to remove the shroud (as it would only help at idle or slow speed) and see what happens. This would be a pretty simple test and might provide you with some additional data points.

My 32 Cabriolet does not have a shroud - it has a stock (recored) radiator, stock fan in stock location, etc.. The engine has been bored to 3 5/16 and total CI is 284. The block was NOS (so no crud buildup). The engine can sit in traffic and not get hot (even on 90 degree days) and it always cools well going down the road (have been up to 75+ a few times).

I'd check the AFR first, re-jet the carb to get the cruise setting down a bit, then see what you get. Then (regardless of the AFR), I'd pull the shroud off and see what happens at both idle/slow speed and higher speed cruise.

Best of luck!
B&S

[jrvariel48]

Originally Posted by Bored&Stroked

Something that I'd try is to remove the shroud (as it would only help at idle or slow speed) and see what happens. This would be a pretty simple test and might provide you with some additional data points.

My 32 Cabriolet does not have a shroud - it has a stock (recored) radiator, stock fan in stock location, etc.. The engine has been bored to 3 5/16 and total CI is 284. The block was NOS (so no crud buildup). The engine can sit in traffic and not get hot (even on 90 degree days) and it always cools well going down the road (have been up to 75+ a few times).

I'd check the AFR first, re-jet the carb to get the cruise setting down a bit, then see what you get. Then (regardless of the AFR), I'd pull the shroud off and see what happens at both idle/slow speed and higher speed cruise.

Best of luck!
B&S

B&S my shroud and fan are one unit so I won't be able to remove the shroud only. I don't have much of a problem at idle or slow speeds just at cruise. I reinstalled the lower grille pan today. I'm not expecting much from that, but I'd like to try it out so I can log the data as I go. The next step is to add the temp gauge in the water pump as Ronnieroadster recommended and see what I have there. Then I'll try bumping up the main jets from #69 to 70 and see what does.
As always, thanks for your input
Joe