The Stovebolt Site Forums The Shop Area Engine Shop Engine heated up at initial run-in

OK, now I got a problem and need some help.
I was excited in my earlier post when my start-up went great,
But when I went for my "20 min initial run-in"...it was a different story.

'53 full pressure 235
First run-up after overhaul and it went like this...

Started up, running great first 6 or 7 min.,
Temp was coming up, thermostat is a 160.
Plan was to continue filling coolant when thermostat
opened.
170-175 I started getting nervous.
180-185, 190 I shut it down 7-8 min into first run-up.
It continued to climb some after shut down.

Here's what I found,
Radiator flows great with hoses disconnected.
I didn't suspect the water pump as I had it on my 216 with no issues.
I don't suspect the belt, fan turns when cranking, crazy as it sounds I didn't remember it during run- up.
Pulled the thermostat, it was open,
set it aside and it cooled and it closed.
Opened the drain plug/valve at the rear of block (driver side)...nothing came out. WTF
Completely removed the plug/valve, filled the neck at the thermostat (with thermostat removed) and still...nothing came out at the plug/valve hole.
I distinctly remember comparing head gaskets (old and new) and they were a perfect match.
The block was cleaned in a tank at machine shop during rebuild.

I'm at a loss as what to do.
Thanks, Jim

This is how I break a motor in. Others may do it differently, this is my routine. You need to fill the system fully with water/coolant. Start motor, 1800-2000 rpm for 20 minutes. If you suspect the system has air, have to get that sorted out, you really do need a full system. Sometimes the cooling system will not handle the kind of running with no air through the radiator needed for breakin so if that is the case and it sometimes is, I have a big box fan that I run through the radiator to get some air flowing. Sometimes, even that will not do it depending on the outside temp, like if I am breaking in a motor at the height of summer. So sometimes I have to run it 10 minutes, then let it cool down and do it another 10 minutes. Then I will generally let it cool and restart to idle and check timing and readjust carb if needed and then sort out whether I have an actual cooling issue. If it stays at 180-190 at idle then I am ok with that. The idea is to get the cam broken in and then deal with other issues after that.

I don’t know about 216 and 53 water pumps and whether one flows more then the other or has different flow characteristics. You might try getting a 235 pump on there instead of the 216 pump.

As for that plug at the back of the motor, yes, sometimes there Is sufficient sludge built up there not removed by the hot tank preventing water from draining from that spot. I would not read to much into that at the moment. When you get the pump off to put a 235 pump on (if they are different) you can look and see how much sedimentary junk is at the bottom.

Poke a wire through the crud the machine shop didn't get out of the bottom of the water jacket. You got panicky and shut things down too soon- - - -a couple of minutes more running, and the temp would have probably stabilized. Were you running a big box fan or a squirrel cage blower to the radiator?

Most block cleaning these days doesn't use strong enough chemicals to dissolve a few decades of rust and crud, but all that should have been double-checked before you put the engine together. Ask the guys who did most of the grunt work on John's 261 about the extremes we went to getting the water jacket cleaned out- - - -it was an epic effort!
Jerry

The late 1955-63 (not 235 vs. 216) water pump has far more capacity than the early pump. Its rated output is 14.5 GPM (gallons per minute) per 1,000 pump RPM, 72% higher than the early pump at 8.4 GPM. In use, the water delivery rates are more similar because the early pump turns faster due to its pulley sizes.
Are you sure your spark lead is correct? Running at near TDC timing will be hot.
Does the fan have a shroud?

Jim, don't panic. You'll figure it out.

Let me offer one other suggestion in addition to cleaning out the rear drain and placing a large fan in front of the radiator.

Next time you fill the block with coolant, loosen the temperature sending unit. When coolant weeps from the temperature sending unit, snug it down. The temperature sending unit is at the top of the water jacket. Using it as a bleeder releases any trapped air as you fill the engine.

Good luck,

Matt

You can also disregard helpful comments such as "it's still tight, it will cool down when it breaks in".
An idling engine needs less than 10 hp, but the cooling system was designed to support the rated power: 10 times greater. The only reason why a functioning system will run hot at idle is no air flow through the radiator. Above 35 mph, the car provides its own air.

Jerry, I'll try poking around up in there to see if I can break up something, it was still climbing at 190, all I could see was $$ signs.
I did not run big box fan or squirrel cage but (I thought) it's a 70 degree day with radiator & fan, I didn't think I would have had an issue.

Dragsix, I don't know if the output of the 216 pump is different from the 235, I'll try to look into that. I didn't see any sedimentary junk at the block opening for the water pump.

Panic, Not certain about the spark lead being correct, I put the flywheel pointer on the BB, put the distributor/rotor on #1 and centered the Advance/Retard hash marks.
I was excited that it started immediately and seemed to be running great.
No shroud, but never had one and the fan is like 1/2" from radiator.
It was running hot at steady 2000 rpm

Maybellene, thanks for the "sending unit" tip, I'll try that also tomorrow.

I didn't have time to trouble-shoot as my brain works a bit slow and it seemed to be "warming up" very quickly with no sign of slowing down.
Here's a question, (just a thought) what do y'all think about maybe removing the temp sending unit, putting a bit of cleaner/chemicals down there, letting it set for a while
then giving it a few short blast of compressed air, (not high pressure) but just something to help move it.

One other thing I just remembered, when I shut it down, it wanted to continue to run, I guess like engines do when they get hot.

Thanks for all the help guys, I really appreciate it,
Jim

Did you drop the speed back to idle before shutting off the ignition? If the speed is much above idle, the engine will "Diesel" from compression trying to ignite the fuel that's still being drawn through the carburetor venturi.

Drain all the coolant out, plug the water pump inlet, and pour a couple of bottles of "C.L.R." tile cleaner into the block through the thermostat housing. Let it sit for 2-3 hours, then flush with clean water and add a box of baking soda and fill with clear water. Run the engine for 10 minutes and flush again. That should do a better job of dislodging the crud in the bottom of the block than the half-donkey water jacket cleaning job your machine shop did.
Jerry

Jerry, if I "had to answer" :-) I'd say yes I did drop it back, but I was so concerned with it heating up...who knows.
I'd like to think my Cajun instinct jus kicked in and I dropped it back.

Edit...I'll definitely also try the C-L-R tomorrow

I have also done break in runs with a garden hose connected to the water pump inlet, the fan belt off, and the upper radiator hose disconnected from the radiator and pointed toward the ground. Run enough volume of cold water through the engine to prevent overheating while breaking in the cam and lifters. It's messy, but it keeps the engine cool.
Jerry

I have a '53 235 with Powerglide engine and I believe that the water pump is the same as a 216 water pump (except for the narrower pulley which doesn't matter as long as you have the correct belt). I don't believe they changed until '55 or '56 when they went with a total redesign of the engine block and the water pump.
Don't freak yet. You have received some very good advice so far.
It is a bear to properly clean the water jackets in these engines without completely disassembling them. It is still a bear to clean them out even when they are completely disassembled.Most machine shops around today do not seem to be very familiar with this problem and it frequently gets missed.
If your thermostat does not have a small hole in it, buy one which has the "jiggle hole" in it. A good parts guy knows what that means. It alleviates the air lock issue you are likely having.

My apologies if I've missed my suggestion in any of the other replies -
You say the water pump was good on your 216 (year?) and that this is a '53 235. There were at least two different pumps that mounted in front of the block and head on various stovebolts, with variations of seals, bearings etc within the types. Early 216 (and maybe some very early 235?) had a backing plate on the pump that had one hole. Later 216 (1942 onward?) and most 235 had a backing plate with two holes. Naturally, it's not as simple as just changing the plates as the holes in block and pump won't line up and the pump castings are shaped to direct the flow to the holes in the backing plate. If you find this is the problem, the good news is that the 2 hole pumps are readily available (Rockauto lists 3 price-points for the '53 235) while the one hole pumps seem to be a "rebuild your pump" at most suppliers.

Grant, great suggestion.

'50 Low Press 216
'53 Hi Press 235, PowerGlide converted to Std with solid lifters & solid Cam

Both of my blocks (216 & 235) have (2) holes on the blocks.
Both of my (216 & 235) pumps have backing plates with (2) holes.

Reason for using the "216" pump was that the "235" pump was "shot".

Thanks again, Jim

Didn't have a picture of backing plate of 216 pump

Although I haven't tried all possible combinations, I believe 2 hole to 2 hole should be OK over the production run.

52carl,
Took your advice on the thermostat, but rather than buy a new one, I drilled a 1/8" hole in mine.

I also decided to do the "compressed air thing" at the drain cock hole, worked great.
5 or 6 shots of air from my compressor nozzle (pressed up against) the hole with the drain cock removed
and it began to flow like a freakin' river.

Jerry, I got my squirrel cage ready to go.

I'm anxious to do it, I'll let y'all know in a couple of days, (waiting on other parts)
This forum has been great, thanks guys..
Jim

Be sure to keep those squirrels well-fed!
LOL!
Jerry

As a back up to the fan, have the garden hose handy to cool the radiator.

I don't mean to jack the thread, but does anyone make a shroud for the trucks that didn't come with one?

I'm curious how the next run goes.

If appearance isn't critical, all you need is the center section (and brand, any engine) that closely fits the blade's sweep. Center it on the blade hub, and fill in the sides, top, & bottom to completely mask the engine side of the core. Pop rivets + rubber gaskets cut from old inner tubes will last 10 years.

SUCCESS !!
Finished my Initial Run-In today, went great.
No oil leaks, Oil press steady at 30.
Water temp slowly rose to 170-175 and stayed there.

Jerry, kept the squirrel watered & fed, he did great :-)

Thanks for the help guys,
Jim

Thanks for follow up. Glad it all worked out.

"I love it when a plan comes together!"

I found a factory one for my '62 C10 on eBay for $25. It needed cleaning and some paint, but I know how to do that. It just took a while for one to pop up.

Good to hear! I thought my oil pressure ran more around 45psi than 30psi, but maybe I'm wrong....


Thanks, but shrouds didn't come on my year. We have sheetmetal equipment at work, so I might make one eventually if we don't go the electric fan route after a 12V conversion.

Hey Lindsey, 1 1/2 and 2 ton trucks came with shrouds that fit the pickup trucks. I have one on my 3100.

Pictures please Carl?

Good to know, thanks!