Christmas parade - failed ?

[White Spyder]

Our Club participated in the towns Christmas parade this morning. Bonnie decided that she did not like idling and creeping on the route even though the crowd was enjoying her presence. The temperature was 65* and within 15 minutes the temp gauge was 220*.  I bailed out and within 2 blocks of heading home the gauge was dropping to 200*.  Within a mile, down to normal operation temperature. 
 

Obviously, she doesn’t like low rpm or speed. I am thinking that I might add an electrical fan to the font of the radiator. Has anyone got recommendations for a 6volt positive ground fan?  Other thoughts and ideas are welcome .

[Booger]

wow shouldnt be doing that. My first thought is a back flush and looking at the water distribution tube. Tstat could be frozen.

[Go Fleiter]

I had one 6V super- atomic- space- fan, but effect was very low!

Now, having 12V available, I have a big fan (from air cond plant).

Effect is a bit better, but far from mastering such precarious situations.

Greetings from Düsseldorf!

Go

[Sniper]

low road speed cooling system issues are usually airflow related, so you are on the path there.

 

That does assume that everything else is as the factory built it and there are no issues.

 

I have no experience with them in their new state, but I assume they didn't over heat like that when new.  So this tells us there is an issue.  One thing I notice when I had my radiator out was that those honeycomb fins sure collect dirt, only reason I noticed it was that I had laid the radiator flat and when I picked it up there was dirt in a honeycomb pattern.  It took me about an hour to get all the west Texas dirt out if the radiator core with my garden hose.  Something like that could be an issue.  Since then, when ever I wash my car I pop the hood and spray out the radiator.

 

One other issue could be pulley sizes, not sure how many possibilities there might be but if the water pump is under driven so is the fan and that would show up in this situation.  A slipping belt could do this too, but I would expect to see charging issues as well.

 

I am sure there are other possibilities that others might think of as well.

 

Though not factory here I have found that a shroud does wonders for this issue.  I had a 64 300 that would do the same as you are experiencing and no matter what I did it would not stop.  Till I found the factory shroud it should of had and put it on.  No more issues.

Edited December 4, 2021 by Sniper

[plymouthcranbrook]

I had issues in the past on other cars where a partially blocked radiator would cause those exact symptoms.  Have you had yours cleaned out or as suggested tried flushing it out?

[Bryan]

I saw someone's post mentioning if you have fluid drive and leave it in gear sitting it will slowly overheat. 

[keithb7]

Your car's heating system is only as good as the weakest part of it. All systems, passages, & parts, work together to keep the engine cooled. 

When you sped up and the engine cooled down again that's an indicator me, as Sniper said that air flow is indeed a strong clue. When you speed up you are replicating the fan pulling air across the rad fins. If a large portion of your external rad fins are plugged up it'll overheat at idle. If your fan is not turning properly at speed at idle, it'll heat up. If your internal rad cores are partially plugged up, water cannot flow properly through the rad at maximum velocity it will heat up. If your timing is set too advanced it will cause extra heat. All these things compound. For example assume each problem causes a 10% reduction in cooling performance. 10 x 5 problems = 50% less cooling efficiency from the cooling system. Maybe it'll be ok driving around town with the 25 mph wind crossing the rad cores. At idle? Overheat.

 

If you have no know history of the cooling system service, I'd consider pulling the rad. Take it a rad shop. Have it boiled. Cleaned. Tested. Flush out the block. replace thermostat. A good start.

[kencombs]

As Sniper said, be sure the outside of the radiator is clean.  Dust, pollen, cottonwood seeds, etc build up over time and can really insulate the metal from the passing air as well as restrict the air.   An electric 'booster' could help, but a better 'stock' fan will also.  I've seen a lot of early Mopars with 5 or 6 blade fans, just not sure what the original use was, but probably trucks.  A smaller water pump pulley will help too, but I'd prefer a fan than moved more air at lower speeds.

[White Spyder]

All the suggestions on the radiator are good thoughts. I should have given more information. When I got the car 7 years ago it had an issue with overheating even when moving. I replaced the radiator with a new one. While the radiator was out, I pulled the water tube for a good cleaning. It was in acceptable condition so it went back in. Also pulled a lower Welch plug and flushed the block. Lots of “mud “ was removed.  Since then I’ve not had an issue. While I have only done a couple of parades, no problem until today. As a side note, I had a different Welch plug spring a leake a few months ago and when I replaced it I took the opportunity to flush the block again. Very little “mud flushed out that time. Could it be and issue with the vanes of the water pump have corroded and not enough water is being moved at idle?  Maybe, it appears to be the original. The car only has 82k on the clock. The fan pully appears to be original as well as the fan. The question about the electrical fan was a thought that would be an easy route without having to replace the pump. 
 

I am definitely open to all suggestions 

[plymouthcranbrook]

I replaced the pump on my 52 back when NAPA had a special rerun on new pumps.  Although maybe 18 years ago. Idon’t remember it being a difficult job at all. I too have seen water pump impellers that seem to lose much of their surface.  Might well be your issue.  

[busycoupe]

My 48 Dodge is all stock and I have had it in several parades. The last was in July with air temp in the lower 80's and lots of hills. As we crawled up the hills my temp gauge would climb towards 200 deg, but on the the down slope would quickly drop back to the 170's.  These old cars should run fairly cool.  

About 10 yrs back I did flush out the radiator, I have a 160deg thermostat.  Also, I had an over heating problem when I first got the car, but after adjusting the points it cooled right down.  You should not need an auxilliary fan for normal  driving.

[DJ194950]

If you fell a fan is still needed for slow speed crawls like a  parades etc. many are available by searching 6 volt auto electric radiator fan on the internet

, but have good luck with a major brand such as-

 

https://www.amazon.com/Maradyne-MP166K-6-Pacesetter-Universal-Reversible/dp/B01GIA6M5M/ref=pd_vtp_3/141-7671105-0805869?pd_rd_w=ePd5l&pf_rd_p=96226b5f-2d9a-439b-be45-97603787c682&pf_rd_r=HKRZXN03E1MPNJ2S6ZYF&pd_rd_r=027ce774-4938-446a-a829-2157232fc51a&pd_rd_wg=s0iJO&pd_rd_i=B01GIA6M5M&psc=1

[Bryan]

I remember someone saying the original water pumps have 2 wings on the impeller. The new replacements have several vanes on the impeller.

[Sniper]

I did a look see of the new style water pump. It has 6 vanes.

 

FYI

 

http://www.yourolddad.com/cooling-system

[desoto1939]

This why the car clubs need to stress to any Parade Organisors that are requesting that antique cars be part of a Parade.  Yes our old cars need to have air movement past the radiator to cool down the internal temperature of the engine.

 

Several of our local parades that have antique cars have now accommidated the cars owners and are now placing them at the beginning of the parade.  This permits us to keep the flow of the car moving and we can keep the engines from overheating.

 

I sugest that anyone one in a car club that is doing a parade stress this point about the placement of the cars in the parade.

 

I had a similar situation in a 4th of July parade in which we were maintaining inline and the cars warmed up so we shut them down.  Upon the official restart I had a hard time starting the car and then the carb overloaded with fuel and I blew-out my muffler.  I limbed home from the parade and did not even complete the parade route.  I was now even offered any help to repair the car so this is another reason why I do not do parades.  You as the car owner do not get any compensation for the parade and if something happens then the parade organisors walk away and say its your problem.

 

After the tune of several hundred dollars for a NOS original muffle and tailpipe I was not happy. So I refuse to do parades even if our club is getting some form of payment. 

[Pete]

I've had my '39 Plymouth in a number of parades. They usually go at walking pace with a lot of stops for groups to do their things for the spectators. Not good for an 80+ year old car in 90 degree weather. Now my local car club insists we go first in the parade. It has worked a lot better.

 

Peter

 

[oldodge41]

I have done some parades. I find the system that works for my car is to keep the rpm level up a little bit and clutch disengaged as much as possible.

[Stargrinder]

Out of curiosity... do you have a fan shroud on your radiator?  When the car is not moving air will travel the path of least resistance ... i.e. around the radiator vs through.  The shroud will help focus the air from the fan through the radiator when your car is not moving.  I was having a similar problem earlier this year and an old timer recommended a shroud.  It actually worked for my application I was surprised.  I was/am running a modern champion aluminum radiator in my '50 Dodge.

 

Just a thought.

[White Spyder]

What suppliers are best for a new pump and I would like to see photos of any shrouds added.

 

thanks

[Sniper]

15 minutes ago, White Spyder said:

What suppliers are best for a new pump and I would like to see photos of any shrouds added.

 

thanks

Kinda depends on what vehicle you have.

 

I can tell you that the water pump I reviewed and linked to in an earlier post in this thread is N/A at Rock Auto anymore, though Amazon has it.