Another Cooling Thread- need advice

serocontra

serocontra

Member
Hello All,

tl;dr:
over heated engine after ten minutes, new leakless pump, good clog test, no oil/bubbles in drained water or radiator, top water connection 215+, car ran great in april, parked since.
oil is currently at full, maybe past full, will remove some today to mid-full line and retest.

Engine overheated this weekend to the point that gasoline wasnt making it to the carb and causing a ton of back firing after maybe 5 minutes on the road.
Took a heat monitor to the engine yesterday and it reach temps in the top water connection on the engine back to the radiator and it was reading well over boiling.
The water pump was replaced this winter with a brand new leakless, removed my 160 degree thermostat, clog tested the radiator- it emptied in less than 10 seconds, timing was done a few month ago and ran very breifly since then.

All I can think of is the head gasket being bad. but the water has no bubbles or presence of oil. i have over filled the oil, and will drain that a tad this after

if anyone has some advice or something im missing i would appriciate it. Ive used youtube and the red book for help.
 
The over-full oil makes me wonder if coolant has found its way into the lower part of the block. If so, could be simple head gasket failure or at worst a crack in the head or block.

However, you mentioned re-timing the car and then putting it away for a time and now it overheats. Why was the car re-timed? Was it down on power before/when it ran hot and overheated?? My gut says to check the timing again.
 
I have a head gasket on standby, so i guess i will be replacing that today.
cracked block....may take longer lol

the man i work on it with is a bit of a perfectionist. he wanted me to redo the timing and so we did it. You may have seen his truck, it is a massive red model a truck that won 3rd place at the Pendleton show this past week.

I will check the timing again later today. i dont think it was bad, but we made it better.
 
If your timing is too retarded your engine will overheat real fast.

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I took a heat monitor to the exhaust system, and nothing read over 600 degrees maybe 650. It didn't get red hot, I have done that before with bad timing.
 
Overheating can also be caused by a lean air/fuel mixture. You stated that the engine got hot enough that gasoline was not getting to the carburetor and that caused a lot of backfiring. Maybe you put the cart before the horse. Perhaps the backfiring was because of a lean mixture and that caused the overheating. I suggest a carburetor clean out. The gasoline can turn to tar after the car sits for a while and that could be causing a lean mixture.
 
Take the heat monitor to the radiator. You should see the temperature higher at the top of the radiator and lower at the bottom. If you have clogged tubes you will see hot spots and cold spots. Check all areas of the radiator.


Bob
 
When troubles start after fooling with something,for the most part it will trace back to what you diddled with last.10 seconds to drain an A radiator is a lot,the number used to be 4 seconds according to old manuals,and the radiator guy told me years ago that really isn't accurate either.But,you were good before.Timing doesn't change itself overnight.If there is anything goopy in the radiator it might fetch up sitting around.Sitting with the cap off or a hose off will let critters in to plug things up.I would make sure it needs a head gasket before pulling the head off.It really does sound like timing,it was fooled with last,check and recheck.
 
Lots of good advice. After you confirm correct ignition timing, I suspect the radiator. I do not think 10 seconds of drain time is definitive.

Try to use a thermal imaging camera (borrow one) and look at the radiator core immediately after you start a cold engine and while it warms up. Use the camera to identify clogged tubes; they will show cool temps after many of the others around them are showing hot coolant moving down in them. Using the thermal camera after the engine is boiling hot will not tell you about the clogged tubes. You need to start sooner.

If your radiator is not leaking, a good radiator shop can pull the tanks off of the radiator, clean the tubes out inside, and put it all back together for $100 with a short turnaround time.

If you suspect a bad head gasket or cracked head/block, you can use a "block test kit" to sniff for combustion gases in the radiator filler neck. It's pretty easy to do; the test fluid changes color if it senses combustion gases. I use a handheld vacuum pump to draw the vapor/air/gas out of the radiator and into the test kit.

A warped head can lead to head gasket failure, so if you do pull the head, check it for flatness after you screen for cracks.

While diagnosing, put a hose on the end of the radiator overflow and route that to a container that you temporarily attach to the oil filler tube or the steering column. I use a clear container. I want to see the fluid level and see if there are bubbles.

Good luck. 'Tis the season for overheating.
 
As a vehicle, the Model A is a little "undercooled." The story of Model A radiators (The Model A Ford as Henry Built it - DeAngelis/Francis/Henry p. 223) is one of ever increasing surface area, augmenting air flow, accommodating heavier truck loads.

The biggest single improvement you can make to a Model A radiator is to change the cross section of the tubes: earlier tended to go "round tube" with a seam. Later the format changed to "oval tubes" made "seamless." Both the numbers of tubes and the numbers of fins increased in time.

A replacement radiator from Brassworks is probably the most expensive - but the most "cooling" of any radiator you can buy. They will make you a "funnel top" EXACTLY as the 1928 car used EXCEPT the tube is seamless - which is probably best you can buy for that application/appearance. I don't believe seamed radiator tubes are available at all - the technology of making tubes has changed (improved) that much.

And even "in the day" Model A drivers/users were having trouble with their radiators. One period solution was the "honeycomb" radiator which was a dandy cooling radiator when brand new, but quickly tended to accumulate deposits from the coolant - and there was no way to "rod" them out.

I would guestimate that most Model A are now on their THIRD radiator, deposits being what they are. The Avatar came with a honeycomb (Probably 2nd radiator) - but that got quickly set aside after a couple of overheating episodes even having read 1980s literature on proper engine timing. (including the pull down on the spark lever and you should hear the points open before one click of the steering column sector.)

Vince Falter today (Fordgarage.com) is where I go now to refresh my Model A Timing intelligence.

Joe K
 
Keith True said:
When troubles start after fooling with something,for the most part it will trace back to what you diddled with last.10 seconds to drain an A radiator is a lot,the number used to be 4 seconds according to old manuals,and the radiator guy told me years ago that really isn't accurate either.But,you were good before.Timing doesn't change itself overnight.If there is anything goopy in the radiator it might fetch up sitting around.Sitting with the cap off or a hose off will let critters in to plug things up.I would make sure it needs a head gasket before pulling the head off.It really does sound like timing,it was fooled with last,check and recheck.
Click to expand...

I agree. Flow from engine is around 32.5 GPM. Remove lower hose and cover with tape. Fill radiator, remove tape, it should empty in 3 or 4 seconds or faster.

Like the Model T, the Model A uses thermo suction but also has a pump.

10 seconds means your only changing the coolant 6 times per minute. Should be about 20 plus times.
 
did it actually boil? or just a temp gauge?

you High oil level has nothing to do with the water boil. unless the bottom of the pan has water in it. then you have an internal coolant leak.
 
hello all, thanks for advice, it's so much i dont even know where to begin so i went with the easiest stuff first since i dont have much time from when i get off work to the late evening.

i lowered the oil level and got a compression gas detector kit.
no gases detected so i trust my head gasket is good.
also redid the timing.

Ran it for maybe 30 minutes with no issues, until i put the cap on.
water was still coming from the overflow, however it did run much cooler than before.
I'll be reinserting the thermostate as that wasnt the issue.
I simply didnt have time to take it for a drive before needing to get ready for work the next day.
however when i put the car into reverse, it started spewing out water.
it took about three gallons when i filled it.
something i've wondered, is it a "self regulating" system? meaning if i put too much water in there will the expansion cause whats not needed to flow out?

should i put a coolant and an cooling additive?
 
Yes, each A is a little different but if everything is functioning normally the radiator will choose its own level (self regulating). Even though you did the gas test it still sounds like a head gasket to me. That’s the only thing (that I’m aware of) that will cause coolant to spew out if it is not overheated. Watch for bubbles in the water with engine at idle. Possibly all the overheating caused the head gasket to fail?
 
There is no need to put in the thermostat. Maybe in the winter when the engine wants to run too cool, but no need now. (Instead of a thermostat, I use a "winter cover" to block the bottom 1/3rd of the radiator and it runs nice and warm. That's what they did back in the '20s and '30s with these cars.)

At this time, just use water in the system while you are sorting it out, PLUS add a bottle of water pump lubricant & rust inhibitor. There are a few to choose from, I use the NAPA MAC-1300. Put the whole bottle in, it won't hurt anything. You don't want rust. You can switch to antifreeze in the fall, before the freeze risk and after you are pretty sure everything is right with the cooling system.

When filling the radiator COLD, you only want 1/2" to 1" of water in the upper tank. If you fill it up to where you can see it over the top of the baffle cold, it is overfilled and it will go out the overflow. You need an air gap at the top of the upper tank.

You can't see the bottom of the upper tank when there is a baffle under the filler neck. I use a wooden coffee stirrer stick (get a handful at your local Starbucks) as a probe. Slip it in to the side of the baffle and touch the bottom of the upper tank. Now withdraw it and see how much coolant you have. Aim for 1/2" to 1" cold.

Now go drive and see if any water comes out the overflow. It should not.

When hot, if you use the stir stick again as a probe, you will find the water level up at least 1/2" more, maybe a bit more, and no higher than the edge of the baffle. Below the baffle is OK.

Many people overfill their Model A radiator and then it pukes out the excess. Then they top it up the next day when cold. Then it pukes it out. Rinse, repeat.

Leave plenty of headroom and it won't.

Also, if you have the style water pump where you can grease the bearing closest to the engine block, give it just 1/2 pump of grease. Not too much. Anything you pump in there ends up in your radiator, but the water pump does need a little every 500 miles.

Now go drive the car and have fun!
 
like mentioned, is true don't fill it to the top. when it stops puking out the overflow, and has cooled a little bit, take note of that level, that is the level to keep it at.
coolant coming out the overflow is not nesasaraily boiling.
 
When I bought mine 3 years ago, I flushed my cooling system several times...at least 5 times with essence of vinegar (at least 25% acid) and water....and then twice with a commercial cooling system flush. Water only ran clean by the last flush. Now I only run an anti-corrosive coolant...no water. After an hour drive at about 85F I can touch my head without it feeling very hot (I do not have a temp gauge). I suspect that there is more garbage in your engine/radiator than you think.
 
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