Cat 951C overheating

New to me a Cat 951C ser# 86J3330
Saved an old 951C from salvage. Finally got engine to run and runs decent after flushing fuel tank, lines and injection pump installed new filter. Has oil pressure on low side but main concern is coolant overheating right now. Have only used water in coolant until i get issue resolved and didnt know what kinda leaks it was going to have. I know this isnt ideal but didnt want to waste couple hundred $$$ in coolant just yet. Have pulled regulator and replaced with new cat. Replaced top radiator hose bc it was missing when i got machine and had bird/mice bed inside housing. Flushed coolant system best i could before replacing top hose and regulator. Machine runs for 20min or so before up to temp and steady increases in temp from there until its in the red until it starts to steam if any tracking or messing around is done at all.. I have shot temp with gun at pump and regulator housing and gets about 200 - 210* but engine dont really want to cool down at any rpm's so i have to shut it down. Dont seem to be circulating coolant as it should so I pulled regulator and left off regulator housing and fired it up. Low idle to about 1/4 throttle there was no coolant pushed out regulator opening. Had to increase speed to half throttle or more before water was pushed out. So i screwed in pressure gauge in the temp gauge plug hole next to regulator housing to see if water pump was indeed pumping pressure. Only had about 1-2lbs at idle and only 5-6lbs at full throttle. I cant find info on this 3304 pc engine water pump pressure specs but figured it would be more that 12-15lbs at full throttle at normal temp. I have a 951C 69H56xx that i did have to pull radiator down to flush tubes and rod them out but how i found out is i pulled both top and bottom radiator hoses and while flushing i noticed i could fill radiator up and have pressure with water hose and would slowly drain from bottom rad hose. This 86J radiator tubes seem to be open as i try overfill radiator fast as i did with 69H i cant overfill faster than it drains thru so im stumped and thinking i have a pump that isnt pumping like it should to circulate normal??? Any help would be appreciated.
Thanks
Steve

Pull the engine oil cooler off and clean it out.
Bob

Bluox said:

Pull the engine oil cooler off and clean it out.
Bob

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I forgot to mention i have already pulled oil cooler and cleaned tubes.

Cleaned oil cooler passages of course both ends.
.

Any other little tidbits you failed to mention?
Well pull the plate off the front of the water pump and check the impeller out.
Bob

Bluox said:

Any other little tidbits you failed to mention?
Well pull the plate off the front of the water pump and check the impeller out.
Bob

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No i havnt yet. Was trying to troubleshoot if these had a certain pressure from water pump first. Figured if i pulled cover i just replace water pump while i was into it. Do you know what pressure these should have between water pump and regulator before and after opening? As other cat engines have 12-15lbs at 1400rpm. Cant find any info on the 3304

A couple thoughts first as Bluox says pull the cover off the water pump and make sure the impeller is tight on the shaft. Second is the water pump has the drive gear attached to the shaft by a single bolt. See attached PDF. If that was loose it would cause pump not to work good if at all.

Any chance of posting an engine arraignment number? Might get some more ideas!

kshansen said:

A couple thoughts first as Bluox says pull the cover off the water pump and make sure the impeller is tight on the shaft. Second is the water pump has the drive gear attached to the shaft by a single bolt. See attached PDF. If that was loose it would cause pump not to work good if at all.

Any chance of posting an engine arraignment number? Might get some more ideas!

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Thank you. Will try that tomorrow.

kshansen said:

A couple thoughts first as Bluox says pull the cover off the water pump and make sure the impeller is tight on the shaft. Second is the water pump has the drive gear attached to the shaft by a single bolt. See attached PDF. If that was loose it would cause pump not to work good if at all.

Any chance of posting an engine arraignment number? Might get some more ideas!

Click to expand...

The engine arrangement is 2P6679 on a 78P engine.
The drive gear is pined to the impeller shaft.
Bob

ZigidyZag said:

No i havnt yet. Was trying to troubleshoot if these had a certain pressure from water pump first. Figured if i pulled cover i just replace water pump while i was into it. Do you know what pressure these should have between water pump and regulator before and after opening? As other cat engines have 12-15lbs at 1400rpm. Cant find any info on the 3304

Click to expand...

I have never heard of a pressure spect. for water pump pressure before.
Are you sure ,you might be looking at the cooling system pressure?
You might just boil the regulator to see if is actually opening I know its new but stranger things have happened.
Bob

I'm glad Bluox hasn't heard of a water pump pressure spec before, because I thought I had missed something big somewhere. If I had to guess, I never would have guessed most water pump would put out 6PSI.

When you got the 210 temps, did you take the temp of the head, or block? They should get to 240 or so before it steams, not that you want to work it hard that hot, but working hard till 200 and continuing to slowly build to 220 will show you what's going on. Take the temps of the block, head, regulator/thermostat, and the water pump inlet from the radiator.

Bluox said:

The drive gear is pined to the impeller shaft.
Bob

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Sorry I forgot about that, it has been probably 15+ years since I touched a 3300 engine. I do now see the dowels in the PDF I uploaded!

I dont see anywhere that you changed fan belt. I have seen an engine over heat from belts that seemed like they were spinning but were so glazed and sitting low in the pulley grooves that they were useless.

Lots of things can cause overheating of the engine coolant. Most of the time its lack of air flow through the radiator core. Check the belts, core for restrictions, fan blade condition, etc........

Get in front of the Rad and with it running, should be air blowing on you all over the Rad

kshansen said:

Sorry I forgot about that, it has been probably 15+ years since I touched a 3300 engine. I do now see the dowels in the PDF I uploaded!

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No problem i pulled water pump and everything looks good. Propeller bolt tight. Bearings is tight and propeller in good shape. Probably been replaced in last few yrs.

Bluox said:

I have never heard of a pressure spect. for water pump pressure before.
Are you sure ,you might be looking at the cooling system pressure?
You might just boil the regulator to see if is actually opening I know its new but stranger things have happened.
Bob

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Yes im old school i tried boiling old regulator and it opened but it was right at boiling before it opened so i replaced it just to be sure and same overheating issue. And yes the water pump should run a certain pressure between pump and regulator i just wasnt sure of psi on the 3304. I have checked a few water pumps before mostly cat truck engines to find a restriction or blockage like an oil cooler. Take checks at a port before and after will tell if cooler is blocked. Cats like 3406 or C15 run about 15psi before the regulator at about 1500rpm's. Not many know to check this or herd of it. Might help someone out trying to figure out blockage or of water pump is pumping right pressure. Thanks Zig

361brock said:

I dont see anywhere that you changed fan belt. I have seen an engine over heat from belts that seemed like they were spinning but were so glazed and sitting low in the pulley grooves that they were useless.

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Belts are like new sitting high in the groove and are tight. Not much wear. Fan is moving lots of air. Looks like belts were replaced not long before i got the loader.

AllDodge said:

Get in front of the Rad and with it running, should be air blowing on you all over the Rad

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Yes i pressure washed radiator when i started on this machine. And its moving lots of air all thru radiator. Fins is open and no bent fins. Thats the first ive seen on old machine. Thanks

Who all here has never herd of water pump pressure specs on the diesel engines..