Cat D4d overheating

Hi need some help please.
Dozer needed an engine overhaul (3304), since then it has consitantly over heated / boiled after a short time working and worse on hot days.
Have stripped and flushed the radiator, checked thermostat and removed centre of thermostat to be able to work longer before boiling, checked water pump, replaced alternator pulley, had the cyl head done, hoses are new.
Am stumped and don't know what else to check.
Any sugestions will help.
Thanks
Ian

First, flushing the radiator might not be enough, it may need to be rodded out to clear out clogged tubes that the flush won't touch. Next, how did taking the center out of the thermostat work? Usually if a bad thermostat is causing one to overheat it's because it's stuck shut so no coolant can flow. Taking one apart, or removing it will usually cause the coolant to flow too fast (((not hanging around long enough to pick up heat like it needs to in the engine and flowing through the radiator too fast to transfer enough heat out of it))) again casing an overheating problem. Another thing I haven't seen personally, but have heard about on several occasions, is a bad water pump. Even though it checks good (ie-the impeller is tight on the shaft) when you look at it, once the system heats up the impeller will slip causing a reduction in coolant flow and an overheating problem. You also said it had been overhauled and the problem started shortly thereafter. If your engine has precombustion chambers it's possible one of them didn't seal and combustion gasses are entering the coolant system that that way. If that's the case eventually it will erode away at the metal around the leak and you'll start seeing coolant getting into the engine when it's not running, but as long as it is running combustion chamber pressures are high enough to keep the coolant out. The same could also be happening due to a bad head gasket but that will typically allow the coolant into the engine much easier than the lower seal on a precombustion chamber will so should be much easier to diagnose as being the problem.

Beyond that I really don't know what else you can check, or do as you've already covered most of the basic checks already. Good luck and keep us informed.

Are we to take it that the engine was not overheating before the overhaul,what did you do, did you change the pistons and liners,if you changed the liners did you check the liner protrusion,if any one of the liners is low hot compression gases can leak into the coolant and cause overheating,the protrusion is crucial,but no point in me going on with it if the protrusion was checked and up to spec,warm the engine up,protect your hand and remove the rad filler cap,fill the coolant up to near the top,start the engine and set the speed quarter throttle,watch the coolant,you are looking for air bubbles coming to the surface,if you see bubbles it's bad news,there is compression getting into the cooling system and you say the head has been checked,the combustion chambers are not pitted and are tight with good gaskets the liners are suspect.
Good luck
AJ

timming slow????

(quoted from post at 12:22:49 04/30/13) Hi need some help please.
Dozer needed an engine overhaul (3304), since then it has consitantly over heated / boiled after a short time working and worse on hot days.
Have stripped and flushed the radiator, checked thermostat and removed centre of thermostat to be able to work longer before boiling, checked water pump, replaced alternator pulley, had the cyl head done, hoses are new.
Am stumped and don't know what else to check.
Any sugestions will help.
Thanks
Ian

Click to expand...

I have a D4D that is overheating as well. Radiator Rodney. Thermostat removed. Still over heats. What was your remedy/fix?

You should start a new post of your own. This site uses two different view formats, Classic and Modern. The only thing people using Classic see is just your post, Classic doesn't move the original post to the top, it stays back in the order it was posted back in 2013.

Jim is right double posts only confuse people, now that you are here read my reply above and check to see if you are getting air bubbles in the coolant, if you are you would need to be checking the precombustion chambers, if those heads crack it is where the chambers screw into the head and the crack can be see when the chambers is out, another thing that was common with those engines were the liners coming loose or pitting, is this a powershift or manual?.
AJ