New Water Pump and still no flow and overheating...

I have the same car as you, same motor. I'm putting money on the radiator being clogged. Mine didn't overheat for 2 years after I put the motor in, then suddenly was overheating. Radiator was like 80% clogged, but water still flowed through the few tubes which were still open. Cost me $100 to get it rebuilt.

 

Sounds like a good idea... (the freezeplug and flush) I know I'm full of "newby" questions but bare with me. Where is it and how do I pull a freezplug?

Oh and it is a 235 from a 56' pickup

 

Moloko... My friend that use to work at a radiator shop told me the same thing... soon as that cash comes in I'll get it worked. I wasn't aware until some of these comments that you could be clogged and still get flow out of the radiator thnx

 

If its the original radiator probably clogged up with rust and crud.

 

Where do you think the junk that clogged your radiator came from??

If you didn't clean out your block you will more than likely have another radiator job coming up soon.

I have found 216s & 235s plugged solid with rust mud packed in most of the water jacket around the back 4 cylinder cores.

 

If you are on a budget:
Do you have or have a friend with multiple cars? Pull a radiator and loosly install it in yours to confirm radiator problem( plugged ) if not, coil a long garden hose in a garbage can. Adapt the hose ends from the rad hoses to said garden hose. Fill the garbage can with cold water and run the car, remember that radiator hoses are designed to take pressure and a garden hose in a garbage can is not, but you are only running it for a short time to test the system, run it with a 4-7 lb cap.
+1 on freeze plugs and having a block plugged with crap.

 

I would drive across the lake and give you a hand but I can't until Friday or so.

If you haven't gotten it worked out by them give me a shout.

 

2 motors, same problem ?
Should be easy to see the problem.

 

looking into rad (empty) with a bright flashlight you should be able to see the tubes inside rad.they will look crusty with scale buildup.a whitish film inside the cooling tubes is the indicator.
rad hoses that collapse usually have a functioning water pump.
coolong system pressure keeps hose from collapsing-the spring inside hose was used for quick filling in factory using a vacum fill system that prevented airlocks.

if heater core is not connected,the heater hoses need to be connected to each other-not dead-ended.that loop assists in flow and keeps pump from cavitating.
also hoses disconnected in pail should indicate if water pump is operating,one should be pumping water at idle.

i have flushed blocks with water and compressed air blow gun with a long tube.
water flushing through various openings and compressed air to loosen stuff.

 

Do you have a powerglide trans.They had a trans cooler and maybe pluged there.
That would be in between two lower hoses.

 

Is there a reason you don't have a thermostat? Maybe without it, the water might be flowing to fast to transfer heat from the engine

 

that will cause hot spots in that area, i was told

 

OK I am Last On The List. So Now Take The Cap Off OK Then get A Oven Meat Thermometer ( From Your Mom Or Your Wife) Put it In The Radiator And Let The Engine Run And Watch The Meat Thermo If It Hits 212 Temp And Starts Pumping Water Out Of The Rad Than It Is HOT. If Not Than Your Dash Gage Is Bad?. To Check The Flo On The Rad Remove The Lower Rad Hose And Put Your Hand Over The Lower Out Let Fill The Rad To The Top Then Remove Your Hand If The Water Dose Not Come Out As The Same Size As The Opening And Spray Out At Least 8 inches Or So Then You Have A Blocked Rad.But If It Dose Spray Out That Good Then Open Up The Drain Cock At The Left Lower Back Side Of The Engine And See If You Get Any Water Out Of It.If Not Remove The Core Plugs,Freeze Plugs Or Welsh Plugs How Ever You Know Them As.And Flush The Block BIG TIME.
Good Luck

 

first year I had my car on the road I had over heating issues. turns out a mouse built a nest in the radiator while it was off the car. A backflush cleared up all the issues.

 

Are the hoses new ? Old ones can collapse inside, and look ok on the outside.......

Just a thought....Look for the simple stuff first.......

4TTRUK

 

Put the thermostat back in. Now, is there a spring in the lower hose? Lippy

 

Thanks for all the info guys... taking it all in...

I think the next two things I am going to do is the freeze plugs and flush the block... then get my radiator to a shop and get them to work it over for me. I am really confident that after doing one or both of those things, this overheating issue will be nipped in the butt.

A lot of good advice, thanks again...
and "goose-em" thanks for the offer of coming over and taking a look. Always appreciated and always welcomed.
Larry

 

I had a similar issue and it turned out to be the radiator.

I had used some "stop leak"(bad idea) and I guess it clogged the radiator just enough to have some flow but not enough.

I pulled the radiator, layed it flat and poured in some muriatic acid. After letting it sit about 15min i flushed it with water and everything went back to normal.

Also, I believe your engine has a drain cock near the lower driver side. Mine was broken off so i pulled the water pump and flushed it with the garden hose while working a coat hanger through the water pump hole. Alot of crud came out. Cesar

 

I recall reading a thread where a 235 had a possible water pump misplacement problem:
The impeller had a different depth, but the pump bolted on and 'seemed normal'.

If all else fails, maybe someone knows of this errant part#...

If you 'nip it in the butt', you're not nipping it in the bud. (green thumb technology)

 

May I suggest you buy yourself a laser thermometer. H F has them pretty reasonable way better for checking just where your hot spots are. Use the KISS system also before tearing everything apart & do just ONE repair or check @ a time to isolate your problem. Do a good backflush on the block with the radiator & heater hoses disconnected also reverse flush the radiator if you haven't already done so. Let us know what yot find or your progress.

 

I used to work in a radiator shop and I'm betting on it being the radiator. Keep in mind that many old radiators can't take being "rodded out" and you may be doing a recore.
Tom

 

Spent a lot of time in a garage/radiator shop, both working on my car, or even a customer's car as "extra help". This was back in the day that '51 would have been only a handfull of years old! While the thought/possibility of old freeze plugs flopping around in the water jacket is very real, the probability of a block clogged with rust and scale that has flaked off now that a long dry water jacket now has water on one side of the wall and heat on the other is much more likely.
A good radiator tech would start out by removing the thermostat (as you've already done), and replace the housing/water neck, but leave top hose off, install on engine neck a longer hose he can aim away from himself and the car's engine but still observe flow from hose.
Remove bottom hose from engine cold water intake and then insert into the hose end the large, cone shaped flushing nozzle which is hooked to both air and water with seperate valves and inlets. Fill the engine block with water and observe outflow.
The tech's experienced eyes will tell him if flow is obstructed and here's what he does when he feels it is obstructed: Taking that bottom hose off, he install a hose on the top neck of engine and uses that cone nozzle fills with water and "bumps" it with air to attempt to blow the obstruction back wards from normal flow and out the engine cold water intake. If the obstuction is dislodged you again check flow in normal direction. If now OK, you've found the original problem and solved it.
Still blocked? then it's time to pull all accsessible freeze plugs and do a lot of probing, gouging, and scraping. plus more flow checks, looking for location(s) of obstruction and then it's removal.
Once you get all the shit out and the flow is free and freeze plugs reinstalled if removed, then comes the radiator. If you removed debis and it cleared flow, then it's almost certain you also have debris in radiator and will need a rodout/boilout to get rid of all the stuff inside the tanks and core tubes.
Dave

 

I have more than a little experience with the old Stovebolt Chevys and my original post said do a BLOCK CHECK !!. Chevy 6s are almost as bad as flathead Fords about cracking, 6 of 10 or so heads that would come in for valve jobs back in the late 50s to 70s when I was around automotive machine shops were cracked. Some never caused heating issues but many did. Before going any further do the dang combustion gas leakage test. If it checks out OK then proceed with radiator and block cleaning.

 

I think on some radiators you cant see the flow due to a baffle installed in the top tank,if you want to see if the pump is working take on of the heater hoses off and fire up the motor.

 

Opps, sorry missed that, just got excited!

 

Can you do a pressure test on the block/rad ?

 

Still waiting on an answer on the trans in this car. What do you have?

 

I had a 52Chevy 2dr ht with the powergulide.
I now have 39 ford,and 52 ford f1,77 firebird.

 

Good advice, no matter how clean your block and radiator are it will continue to heat up if combustion gasses are getting into the cooling system. The kit is fairly inexpensive and super easy to use.

Once you rule out a bad head/head gasket proceede with the block clean out. I had a core plug that started weeping on my '37 so I knocked out the ones I could get at, the amount of crap in the block was unbelieveable. It looked like a mix of casting sand and rust particles. Loosening up the sediment with a coat hanger and flushing with a pressure nozzle and garden hose eventually got most of it out. Once the core plugs were back in I filled the cooling system with white vinegar and let it sit for several days. I was afraid commercially available cooling system flushing chemicals might be too aggressive and cause more leaks. The vinegar came out bright orange so I ran water through it until it came out clear.

 

lets see>two different engines same problem ...what is common to both???

maybe the rad ...rod it out or get a new rad.........