Hi Volume Water Pump

[captden29]

I read the post on the hi volume oil pumps and started thinking about my water pump. I have looked for, with no success, a hi volume water pump for my 265 in my 54 Windsor. I do not think they exist. my problem is that even though I have pulled the core plugs and flushed the block, it will still try to overheat in traffic on a hot day at idle. when I look in the top of the radiator at idle there is absolutely no water flowing. the water pump is the original, but rebuilt. my thought at this point is the impeller inside must be worn enough to only pump well at higher speeds. I believe NAPA sells new pumps. has any one ever had the kind of success I am looking for by just putting in a new pump? the car has 118,000 miles on it but runs very well. the radiator has been recored. timing is about 2 BTDC. I would like to be able to drive on the hot north Carolina days, but with this issue I cannot. the heat riser appears to be working, but I leave it closed[ full exhaust flow straight out]. however, open or closed does not matter anyway. thanks for any tips.   capt den

[Young Ed]

Do you know which style impeller you have? This is an old pump and a modern replacement. I suspect the modern one would flow more.

 

[P15-D24]

One is not available probably because it is not needed if your cooling system is properly maintained. You mentioned flushing the blocks with the core plugs out but not mention of with water distribution tube. It is critical for upper block cooling delivering cooled water direct to the rear of the block.  I personally have driven my P15 in 100 degree weather while pulling a 1300 pound trailer and didn't have a boil over (160 degree stat). If it is running hot you still have some work to do to find what is not flowing correctly. 

[busycoupe]

You did not mention the thermostat.  Perhaps you should put in a new one.  They are short money. 

Dave

[captden29]

not sure about the impeller type. the water dist. tube has been replaced. the question I have is should I see water being pumped into the top of the rad. when at idle. right now there is no water movement into the top at idle.the other day when I was working on my 94 gmc truck I opened the rad. cap at idle and there was a strong flow of water into the top of the rad. made me wonder why my flathead had no water flow at idle. is that normal? most people say the flathead 6 is not prone to overheating, but I cannot get mine to run cool except in cool weather. I even added an electric cooling fan in front of the rad, which just slows down the overheat in traffic. thanks for the replies so far. there is a new thermostat. capt den

Edited May 30, 2013 by captden29

[Plymouthy Adams]

you mentioned that the flow was not what you considered good at the time you looked into the radiator..have you in fact done a flow test...your water must exchange in the radiator in order for the passing air to remove the heat...a thermostat serves a number of purposes...one is it controls the amount of flow also when open by the very size of the discharge..this ensures that while the wter is in the block it will allow proper saturation of heat in tot he water to be exchanged at the radiator..to fast a circulation of water will not allow absorption of heat...an area of the system many overlook...

 

also ensure the lower rad hose is not restricted or folded/pinched...

Edited May 30, 2013 by Plymouthy Adams

[greg g]

By rule of thumb running hot at idle is usually an air flow problem, whereas running hot at cruise is a coolant flow problem.  Before looking at a new pump. I would be looking at belt tension, plugged radiator fins, fan proximity to the core.  And of course asking the age old question is how hot is hot???  Are you going by the dash gauge, an aftermarket gauge, a thermometer in the coolant a the rediator??

[captden29]

funny, but as helpful as everybody is on this forum, nobody actually answered my question. should I see water flowing at the top of the rad. at idle? I would think I should. upper and lower hoses are new. capt den

[Dave72dt]

Onced it's warmed up, you may see a disturbance in the water at the top.  It doesn't flow that much at idle so it won't create much turbulance and if the neck is not directly under the fill cap it will be harder to see.

[Scruffy49]

Trickle yes, flow rate like a modern vehicle, no. Even if the radiator is recored with a modern fin and tube versus the old style honeycomb core, you won't see a whole lot of coolant flow. Doesn't matter if the engine is an L4, L6, L-V8, or early OHV straight engine. The older blocks don't flow as high a volume of coolant as newer blocks. Like Tim said, the older designs tend to let the coolant heat soak in the block longer. It used to bug me with my V8-60 32 Victoria until I got used to it.

[Rodney Bullock]

I had concerns like yours some years ago. I made two changes, first I changed my thermostat to a 160 these old cars look at that as the norm. Then I changed the water pump to the one that NAPA sells. It is a non grease fitting one. Once the thermostat opens the water flows even at idle. The coolant mixture is very important as the timing of the motor. All these things together make these cars run cool even in hot weather. Mine runs on the hot side with air flowing and the car moving I have not had any problems. If you look back on the archives with my car you will see some of the things I have done. 

[_shel_ny]

My D24 shows very little movement at idle. If I hold the throttle open to about 2K I can see the coolant swirl a bit, but not like I have seen newer systems flow. Last trip out was in 80 degree temps, and held close to 160 until slowing to turn around (quickly to approx 175-180), but then dropped quickly at idle with no load.

[Jerry Roberts]

 Do you see water flowing in the top of the radiator at slightly higher RPM s ?  Also when you check the lower radiator hose for collapsing , check it at higher RPM s . 

[captden29]

thanks for the info on the water flow at idle. I will check the thermostat and put in a 160 if it is not one already. I will check the lower hose at a higher rpm. where can I find a diagram of the water flow through the engine? would be interesting to take temp. readings along the path of flow. also I will probably change the pump. the one in there is the original, but rebuilt about 7 years ago. I think rebuilding just changes bearings and seals, so the original impeller could be lacking in pumping ability.  I will post some results after we get the hot hot weather again.   thanks,   capt den

[Guest bewillie]

I can feel your frustration.  First forget every thing you have done because you are missing something some place. First ck your lower hose to make sure it isn't sucking shut when you rev the engine.  Next replace your thermostat. Run the engine long enough for it to heat up. At this point you should see movement  of th water in the neck. The faster you rev the engine the faster the flow will become.  If you see no movement when she is hot I almost guarantee your thermostat is not opening. If all that fails I would pull the bottom raditor hose and see how fast the radiator emptys. Hold your hand over the outlet and fill with water, on removing your hand the radiator should empty in one big gush. If it just flows out it is stopped up. If the radiator is ok,thermostat ok then you know where you have to go next. Yes some place in the engine. Remove all freeze plugs, dist tube and power flush both ways. Better yet remove the engine and hot tank and rebuild. Never run without a thermo as this will sometime cause over heating also.

[James_Douglas]

There is a man who runs a large pump manufacturing and repair business here in Northern California.  He also has an interest in old Dodge Trucks.  He had a batch of custom brass impellers made up.  He also uses sealed bearings-shafts that are better than average quality.  I had him rebuild one of my pumps.  It is on the 5000 pound '47 Desoto Suburban.  The pump was not cheep (Northern California Labor rates you know) but it has worked good for the last few years including the drive up to Reno a couple of years back in the heat and long climb up Interstate 80.

 

I think they moved from Berkley to Tracy, CA.  The name of the place is Arms Pumps.

 

In a car with a stick and a regular clutch, I would not bother with the fancy rebuild.

 

On cars with the fluid coupling in modern traffic, I would.  Even Chrysler in its service information was telling customers that they should not "sit" with the fluid coupling engaged for more than 5 minutes at a stop.  I have found that in very slow stop and go driving or at a stop if the fluid coupling stays engaged that the drag on the engine does cause it to heat up.  So, you have to dump it into neutral a lot or beef up the cooling system performance at idle. 

 

In my case on the big Desoto, I used an Arms rebuilt pump with better impeller, a radiator with dimple tubes , and a switched booster 6V fan on the front of the radiator.  All this, with a clean block and a good distribution tube and the correct type thermostat and the beast runs fine heat wise.

 

James

[Don Coatney]

James;

Thanks for posting. I had not given the fluid coupling drag any thought in engine heat build up. But now I know. Makes me wonder how much an automatic transmission left in gear while stopped for extended periods will also build engine heat? I am thinking about converting to an automatic transmission in my car. If I do so it may be time for me to upgrade to a new radiator and it seems a transmission cooler wouod also be in order.

[meadowbrook]

I know this is an old topic but I am questioning the various recommendations on using a lower temp opening thermostat to solve cooling issues. Assuming the stat opens, why would an earlier opening unit help an overheating engine? I can only see it lengthening the time it takes to overheat. If the cooling system is not able to cool the engine, it will eventually overheat, no matter when the thermostat opens.

Also, on this topic, my D34 has the original radiator and engine. I did sort of flush the system at home when I replaced the water pump as a preventative measure. I was amused to see the old pump's paddle wheel as compared with the new pump's more modern rotor.

Anyway, my engine never overheats, the only issue I encounter on long hot periods of idling in traffic is stalling, which I think is fuel boiling in the carb.

So my point is, these cars seem to have adequate cooling systems, so overheating issues re likely due to something being deteriorated in the system, like the water distribution tube, or plugged radiators, etc. even my timing is advanced to 5 deg btdc and I have no issues.

[Plymouthy Adams]

if your system is inadequate to handle the heat exchange or you have attributing factors like high timing, blow gaset etc..you are right, only delaying the inevitable..you need higher temp to keep sludge build up at a minimum...look at todays cars...avg 195-205 operating temps..the margin for boil is greatly increased though due to high pressure systems and coolant qualities..

[Tones52]

greg g mentioned in post #7 the proximity of the fan to the core as being a possible factor in overheating

 

I'm putting my 52 Plymouth back together after replacing the water distribution tube and planned on using a 6 blade fan that I purchased from Vintage Power Wagons. (see below)

 

After reading in another thread that a member had a problem with a 6 blade fan not fitting in his 50 Plymouth, I put my pully, fan and radiator in place and there seemed to be just enough clearance; however, the 6 blade fan is definitely closer to the radiator than the 4 blade fan was. If I have to remove or change the fan then the radiator will have to be pulled.

 

So my questions are: 1) how close is too close for the fan & radiator and 2) has anyone put a 6 blade fan in the 51/52 Plymouths?

 

Thanks for any assistance/insights provided.

 

Tony

 

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[DJ194950]

How is it?

My current setup in my 50 with 4 blade stock fan is 5/8" clearance to the aftermarket 3 row alum. radiator i'm running works good.

Ideal is 1" approx. per articles i've read but they said 1/2" absolute min. but not to good.

Why am i running a 3 row rad. you ask?  Price on ebay was about $10 more than a 2 row, so why not.

Then clearance problem was at the belt/alt. pulley and too close to the rad. but that was a 6 blade that was on a clutch fan. Blade pitch was fairly steep, so probably was most of the cause. Your blade my work fine.

 

I hope I did not lead you astray at all.

 

Good luck,

 

Doug