Runs warm...

[Jim Saraceno]

I know this subject has been raised many times and I have searched the archives and still don't know where to go from here.

This is what I have. It's a 230 engine, internal bypass block, head and water pump. An external bypass thermostat housing with the bypass plugged with a rubber stopper. A 160 deg. choke type thermostat.

The engine has been rebuilt, all the freeze plugs and distribution tube were pulled, the block was hot tanked and new tube and plugs were installed. I keep the timing close to TDC. I just did the test where you measure how high the water gushes when you fill the radiator and pull the plug at the lower hose connection. It easily gushed the 5-6" the manual states. I also checked the temperature gauge against a thermometer and it seems to be accurate.

The symptoms are: On a cool day I don't have much of a problem. When the temperature starts to reach the 80s, the temps will start rising to 200. It seems to slowly rise as I drive 60 mph or faster for any length of time. If air temps get to the 90s and I drive in the 60s mph, the gauge will creep up close to pegging it so I'm sure I'm running close to 212.

I'm not sure what else to check. I read about many of you who travel higher speeds for great distances and I don't have the confidence to do that with my car because of the temps it runs.

Is there any way that not having the splash pans on bottom and side vent pans not installed are causing the air to flow improperly thereby not getting proper cooling?

Any ideas?

[TodFitch]

It might be that the cooling system is okay but the engine is putting out more waste heat than it should...

How is the timing?

Is it running lean?

Are the brakes dragging?

On the cooling side, was the radiator painted? If so was it with a radiator paint or something else that might be a bit of an insulator.

[Niel Hoback]

For a few bucks, I would temporarily replace the temp guage with a cheapie from walmart and see if it really is getting that hot. Better to just stick a thermometer in the radiator tank and see how close the readings are to each other.

[55 Fargo]

How about the rad has a problem dissipating heat at higher ambient temps.

Do you notice this when your car is going with the wind, as opposed to going against the wind.

Is this a problem of reduced airflow through this rad for some reason?

I wonder if this situation could be reversed with a new rad.

I would caution on the cheap gauge, as they could be faltered very easily, right out of the box.

How about a lazer thermometer, check temps on block, rad etc, see what readings you would get.

I also have some acute problems with my engine in the 47, block is pronounced clean, water dist tube was pulled cleaned, water pump is good. The rad is a D24, honeycomb design, has good flow, was boiled out, but having said that, is it's ability to cool hampered in anyway, because of any internal problem such as old antifreeze build up, any partial restrictions. Being a honeycomb rad, it cannot be rodded, so I think mine is up to snuff, but who knows.

Could the problem be related to timing and advance, lean fuel mixture, or anything related to ignition.

If I get another rad, gonna try an after market aluminum rad, would no doubt transfer heat a lot more efficiently than a stock rad.

I also noticed 1 thing, I was running my engine this winter, and had the rad blocked by a heavy sheet of cardboard, the temp went up to 200, once removed it cooled down fast, in summer the under hood heat, would be much hotter than in winter, so my engine cooled down quick, restarted very easy too, once I shut her off and re-tried to start the engine.

I also get concern on very hot days, and am not sure if I could doa major long highway drive on a 90 degree day up here, especially on those super humid days...

[Jim Saraceno]

How is the timing?

Is it running lean?

Are the brakes dragging?

On the cooling side, was the radiator painted? If so was it with a radiator paint or something else that might be a bit of an insulator.

Timing near TDC

Carb adjusted according to manual

No brakes dragging

No paint on the radiator

For a few bucks, I would temporarily replace the temp guage with a cheapie from walmart and see if it really is getting that hot. Better to just stick a thermometer in the radiator tank and see how close the readings are to each other.

That might not be a bad idea. Do you think one of those infrared temperature sensors would suffice?

Todd, Don't you run your 4 cylinder at speeds of greater than 60 mph great distances with no overdrive and a 180 deg stat?

[55 Fargo]

Timing near TDC

Carb adjusted according to manual

No brakes dragging

No paint on the radiator

That might not be a bad idea. Do you think one of those infrared temperature sensors would suffice?

Todd, Don't you run your 4 cylinder at speeds of greater than 60 mph great distances with no overdrive and a 180 deg stat?

Jim, my infared sensor, works extremely well, on hot days, once engine is showing 160-170 on stock gauge for example, the temp on head is almost bang on, with in a degree or 2.

The rad is always slightly cooler, and the rad is cooler toward the bottom of it's core.

I can tell you that I have run 2 different equiss temp gauges, then were bot out, by 10-12 degrees over actual coolant temps, so they were not reliable.

Try a cheap cooking thermometer, place in the top of the rad, on hot days or as soon as you can get this car out and driving where the temp goes up to the 212 range, then check the top of the rad, if it is reading 175, then you have a gauge problem perhaps.

The infared sensor will allow you to check the head, front to back, the rad, the coolant in the top of the rad, far more comprehensive, and heck there about $29.00. I would do this first and see whats up.

If there are high temps, verifying the stock gauge, you can eliminate the gauge as suspect.

Then systematically you can go through all the usual components, and eliminate all suspect or not suspect items.

I know for me I would get a brand new rad, but cannot afford it now, and I do know some Guys have bought new rads, and the heat problems persisted.

Have you ever had to replace the head gasket, could it be leaking any exhaust gas into the water jackets?

[Desotodav]

I went through exactly the same problem recently Jim and have just found the solution. Did you have your engine sitting dry for any amount of time after the rebuild? I had my 218 motor rebuilt and let is sit dry for a while before installing it in my truck. Metal scale built up in the block and was pumped into the radiator (which was previously dismantled and cleaned out) as soon as I went for a drive and got the motor up to operating temperature. I had the block and radiator flushed and now I don't see the temp gauge go over 160. I was told that usually a circulation problem is to blame if your vehicle overheats whilst driving. I was surprised at the amount of gunk left on the workshop floor that came out of my vehicle during the flushing process. I was then told that the other two thirds of it had washed down the drain.

I hope the same process works for you. Other things that I checked were: suitable radiator cap, correct thermostat (not installed in my case), timing, water pump flow, evidence of head damage, or faulty temp gauge.

Good luck with it. I would be interested to hear of your solution.

[John Reddie]

I would have the radiator flow tested to be sure it is not plugged if you have not done so yet. When the outside temperature get warm and you are driving at highway speeds, the coolant is moving rapidly through the system. If the radiator is partially plugged up, it cannot cool the engine sufficiently because of this. It is less noticeable when the outside temps are colder. Even if the radiator looks clean when you look into the opening, it could still be plugged inside. Good luck to you.

John

[55 Fargo]

I went through exactly the same problem recently Jim and have just found the solution. Did you have your engine sitting dry for any amount of time after the rebuild? I had my 218 motor rebuilt and let is sit dry for a while before installing it in my truck. Metal scale built up in the block and was pumped into the radiator (which was previously dismantled and cleaned out) as soon as I went for a drive and got the motor up to operating temperature. I had the block and radiator flushed and now I don't see the temp gauge go over 160. I was told that usually a circulation problem is to blame if your vehicle overheats whilst driving. I was surprised at the amount of gunk left on the workshop floor that came out of my vehicle during the flushing process. I was then told that the other two thirds of it had washed down the drain.

I hope the same process works for you. Other things that I checked were: suitable radiator cap, correct thermostat (not installed in my case), timing, water pump flow, evidence of head damage, or faulty temp gauge.

Good luck with it. I would be interested to hear of your solution.

restriction in the head or water jacket, water dist tube, or rad will create heat problems.

Most likely if the water jackets were plugged, or any coolant hole or at the back of the engine or head, the engine would heat up quickly with any driving, or outside ambient temps, but of course, higher outdoor temps, higher speeds, more engine RPM, and things get hot in a hurry.

I am surprised that you engine builder, missed so much crud, was your engine hot tanked prior to being rebuilt, you stated it sat dry, but sounds like a lot of crud was still laying in the water jackets, waiting to flow out into the rad.

the usual "chili crud", the rust, old glycol, usually does not flow out very easily, it has to be rodded,prodded, and flushed out to be rid of it. Hot tanking , would work well, but I did clean up my block quite well with the engine in the car, or at least I hope I did.....

[greg g]

Do you have a heater??? What happens if you roll the car out of the garage get it up to what ever ormal temp is then turn on the heater? When doe the car over heat, while running sown the road or while idling/sitting at stops? If you icrease the engine speed at idle does the temp increase decreas or no change?

[Desotodav]

My motor was allegedly 'hot tanked'. It did sit in the back of my garage for a while whilst the rest of the truck was built. I did a few short trips initially and did not notice the high temps so much. It wasn't until I took it for about a 1/2 hour drive on a hot day that I noticed the overheating problem. I'm glad that I sorted out that problem, I can move on to the next problem now - a stripped thread from the bolt at the bottom of the timing chain cover.

If it wasn't for bad luck, I'd have no luck at all!

[garbagestate 44]

There's always the chance that the thermostat, even if new, isn't opening at the temperature thats stamped on the bulb or maybe it's hanging up somehow.

[TodFitch]

Todd, Don't you run your 4 cylinder at speeds of greater than 60 mph great distances with no overdrive and a 180 deg stat?

Actually, it is a 6. The first year of the 6 with a number of differences from the later cars especially on the cooling. The water jacket only covers the top of the cylinders, there is no water distribution tube and the thermostat is the internal bypass type. I'm running a 160F thermostat and the calibrated dash gauge settles down between 180F and 190F under high speed, hot weather conditions.

For long distances, 60 to 62 MPH is my max cruising speed which I've done in 95F temperatures. I have had it up to 70 for short bursts but that is pretty scary and is over speeding the engine. You'd really want to address suspension, steering and braking system design issues if you wanted to travel above 60 MPH for any distance.

Only heat related problem I've had recently is "vapor lock" when stopped or idling after running at highway speeds for a while (hour or more) with high ambient temperatures (above 90F). The factory did not put a heat shield on the fuel pump and it can get quite hot from the manifold heat once the airflow stops. My current solution is to pour a bit of drinking water on the fuel pump to get it cool enough to start pumping again. Fortunately it has only happened a couple of times. I did not have that problem before last summer but that was the first summer with ethanol in the gas. Before that we had MTBE. Seems like gas with ethanol is more volatile.

Actually, thinking back on it, I believe the ambient temperatures when I had the vapor lock problem on restart were closer to 100F than 90F...

Edited March 1, 2011 by TodFitch

[55 Fargo]

Do you have a heater??? What happens if you roll the car out of the garage get it up to what ever ormal temp is then turn on the heater? When doe the car over heat, while running sown the road or while idling/sitting at stops? If you icrease the engine speed at idle does the temp increase decreas or no change?

Hi Greg, I believe Jim's main concern was higher speed highway driving with warm to hot outdoor temps of summer.

His engine temp climbs super high on the highway, he did not state if this would cool down if he reduced speed, , or used the heater as a secondary cooling rad.

I know in my case, the few times i have got my engine real hot, near 200, was on super hot days, and once the engine got this hot, heat did not escape or transfer much under hood, had to stop and let her cool down, preferably in the shade.

I have no idea what y causes are on the hotter days, but do notice these co-relations,

1) going with wind makes it worse

2) under hood temps cannot escape well

3)higher speeds higher engine rpm = higher engine temp

4) my rad is almost 16 inches back from the grill, I have no shroud, possibly causing poor airflow over rad,with certain conditions

I do not see an engine going up to 190 or so on the highway as being all that bad, but if it climbs and will not cool down,and under hood temps cause other issues, then not sure what the answer may be.

I think, and maybe I am wrong, that running at 160, may be too low, 175-180 maybe the optimum running temp, a lot of us like to stay at 160, thinking we have a larger margin before getting to hot, and boiling over. The t/stat will determine the engine temp, while in warm up, or on real cold days will regulate a stable engine temp, but on warm days, a warm engine will climb,and sit at its level I suppose.

Right now if I were to drive my car, with it's 160 t/stat,it would be closed a lot of the times, as it is so cold, the engine would be fighting to stay warm, as it is about -20 with the wind today, bloody awful..............LOL

[55 Fargo]

My motor was allegedly 'hot tanked'. It did sit in the back of my garage for a while whilst the rest of the truck was built. I did a few short trips initially and did not notice the high temps so much. It wasn't until I took it for about a 1/2 hour drive on a hot day that I noticed the overheating problem. I'm glad that I sorted out that problem, I can move on to the next problem now - a stripped thread from the bolt at the bottom of the timing chain cover.

If it wasn't for bad luck, I'd have no luck at all!

Typically they start to show there heating problems on warmer days at higher speeds, with a longer duration.

What you may not see on cooler days for shorter runs can magically appear ona hot day, at higher speed and engine RPM

[55 Fargo]

There's always the chance that the thermostat, even if new, isn't opening at the temperature thats stamped on the bulb or maybe it's hanging up somehow.

Yes that would be an issue, I had chased that before, and have never been that lucky, maybe Jim can tell us if he has verified his t/stat

[Rodney Bullock]

Hey JIm, You know a newly rebuilt motor sometimes runs a little warm at first. Don't be to alarmed by it. Please make sure your radiator is working or "flowing" as it should. It funny but sometimes a motor "gets well" after you drive it and experiment with the timing. You said that you tested the flow at the lower radiator hose. I would get a infrared temp gun. I found that aiming it at various points in your water system can help pin point where you are having a build up problem.Start at the water neck, then the radiator top and then the water pump. It will tell you where your pproblem is, I had a problem with my Studebaker and found that the water pump although new was not pumping right.

Jim, if you have a heat riser make sure it's not stuck or closed as this will make your car run hot in the warm months. I found that out the hard way as well. Hope this helps.

[Phil Martin]

My 230 had same problem. New radiator didn't hrelp much. Flushed motor repeatably water tube is clean. I put a 7 blade fan on it and problem was cured.

[55 Fargo]

Hey JIm, You know a newly rebuilt motor sometimes runs a little warm at first. Don't be to alarmed by it. Please make sure your radiator is working or "flowing" as it should. It funny but sometimes a motor "gets well" after you drive it and experiment with the timing. You said that you tested the flow at the lower radiator hose. I would get a infrared temp gun. I found that aiming it at various points in your water system can help pin point where you are having a build up problem.Start at the water neck, then the radiator top and then the water pump. It will tell you where your pproblem is, I had a problem with my Studebaker and found that the water pump although new was not pumping right.

Jim, if you have a heat riser make sure it's not stuck or closed as this will make your car run hot in the warm months. I found that out the hard way as well. Hope this helps.

All good advice Rodney, especially the heater riser, some say this is not so, but I know if the heat riser flap is tuck in the warm-up position, it can add to the engine heat problems..

[55 Fargo]

My 230 had same problem. New radiator didn't hrelp much. Flushed motor repeatably water tube is clean. I put a 7 blade fan on it and problem was cured.

This is interesting, can you post a pic of the fan, what type, etc?

I also agree air flow across the rad, is absolutely necessary. I always thought, the fan, was most important at lower speeds say under 40mph,and especially at super slow speeds, any ideas?

[Young Ed]

A tight rebuild will run hot for the first 1000-1500 miles. Dads 51 convert did that. Finally settled down on our way back from the black hills in 2000. Also 5-6 inches of water out of the radiator isn't enough. I know thats what the book says but it should be higher. We got that much out of a radiator that was 1/2 plugged up with mouse nests. The next one we tried was almost double.

[RobertKB]

Very simple solution could possibly be the same as I had with an old '38 Dodge I had for a while. Car always ran hot. Had rad flushed and block. Still hot. Took out thermostat and put in a new one. Still hot. Finally read somewhere that there is supposed to be a rubber ring on top of the thermostat that seals the space between it and the housing. Without it, even when the thermostat was closed during operation, you still have a considerable amount of water sneak past the thermostat. It is like a car with no themostat that runs hot, especially on the road as the water never gets a proper chance to cool in the rad. I found a rubber ring and put it in and the temperature was noticeable cooler when on the road, especially the highway. I had the exact symptoms you described and that was my fix. Do you know for certain or not if you have that rubber ring? It is not an O ring but is flat and wider. Good luck with your problem.

Edited March 2, 2011 by RobertKB
Grammar

[Jim Saraceno]

Thanks for all the tips!

To answer some of the questions, the engine rebuild was a few years ago. I'm sure I have several thousand miles on it since then. I have checked the thermostat to verify it is opening at the proper temperatures.

I think what I'll do next is to get one of those infrared temperature sensors and see if I can find any hot spots anywhere.

As I said before, the radiator seems to have proper flow. Back in my VW days, people used to take the shrouds off the engines to let the air flow better but others claimed that disrupted the proper flow of air across the cylinder heads and actually made the problem worse. I'm going to re-install all the sheet mettle around the engine compartment to see if that could be a contributing factor.

Of course, right now, I won't have any problems as it is cool and in the 60s or lower. I won't know much until the temps start hitting the 80s. Also, maybe I'm just asking too much from my car to drive 60+ mph on a 90 deg day for any length of time with the 4.125 differential and no overdrive. If I keep it down to the mid 50s, it will creep up to 200 but will max out there.

Thanks again, I'll let you know if I find anything.

[55 Fargo]

Very simple solution could possibly be the same as I had with an old '38 Dodge I had for a while. Car always ran hot. Had rad flushed and block. Still hot. Took out thermostat and put in a new one. Still hot. Finally read somewhere that there is supposed to be a rubber ring on top of the thermostat that seals it space between it and the housing. Without it even when the thermostat was closed during operation you still have a considerable amount of water sneak past the thermostat. It is like a car with no themostat that runs hot, especially on the road as the water never gets a proper chance to cool in the rad. I found a rubber ring and put it in and the temperature was noticeable cooler when on the road, especially the highway. I had the exact symptoms you described and that was my fix? Do you know for certain or not if you have that rubber ring? It is not an O ring but is flat and wider. Good luck with your problem.

Something like what you describe Rob, makes a lot of sense.

In my case, I have a more modern t/stat and housing for the internal by-pass type water pump.

But I do havea 1/8 hole drilled in the body of the t/stat, to allow air to escape on fill ups of coolant. I also notice in winter, my t/stat will not keep the operating temp at 160, I believe it has a very weak spring, and does not work well....

[Young Ed]

That thermostat Robert describes is available new from napa. I have one in my p15.