Bobcat 743B Getting hot

[prowedge]

I thought it was the water pump making noise but when I removed the fan belt cover the noise went away, I think the alternator may have been slightly rattling against it. I pulled the water pump off and it looks decent, the bearing seems fine and the impeller looks good to me but please see below. I found a slight bit more pitting from electrolysis thought. I also noticed that when I turn my cab heater on the temp gauge drops down about an eighth of an inch immediately, could that be caused by a ground issue?

 

[prowedge]

After you get the radiator hot tanked and engine flushed, do as UnexpectedBill suggests and inspect the coolant pump impeller for cavitation pitting and electrolysis corrosion. And after you have thoroughly scraped and cleaned out the heater, install an AWG 10 bonding (ground) wire from it to the engine block. In essence, you have a dissimilar metal "battery" here with the transient current being carried in the coolant (this is also why there is usually a separate ground wire on an aluminum alternator).
For a flushing agent I recommend an oxalic acid solution or CRC Evapo-rust (remove the thermostat for flush and rinse). For coolant I recommend (and use it in all my equipment) Final Charge 50/50 premix.

Would a quart of CRC do it of should I buy a gallon? By flushing, am I just pouring it through there or Should I close the system and let it sit awhile and then flush with water?

 

[Mustang Guy]

Would a quart of CRC do it of should I buy a gallon? By flushing, am I just pouring it through there or Should I close the system and let it sit awhile and then flush with water?

Buy enough Evapo-rust to fill your cooling system. Follow the instructions on the container.

 

[Mustang Guy]

I thought it was the water pump making noise but when I removed the fan belt cover the noise went away, I think the alternator may have been slightly rattling against it. I pulled the water pump off and it looks decent, the bearing seems fine and the impeller looks good to me but please see below. I found a slight bit more pitting from electrolysis thought. I also noticed that when I turn my cab heater on the temp gauge drops down about an eighth of an inch immediately, could that be caused by a ground issue?

Quite possibly a ground issue, or voltage drop caused by heater motor running. Time to hook up those ground cables to the engine.

 

[UnexpectedBill]

Quite possibly a ground issue, or voltage drop caused by heater motor running. Time to hook up those ground cables to the engine.

I agree- voltage drop due to the fan motor load when the machineisrunningat idle. If you increase engine rpm and it is less of a drop that will pretty much confirm it.

 

[haymaker]

Evapo-rust THERMOCURE By CRC has simple to follow directions on the bottle. 1 QT treats a 3 gallon system.

 

[prowedge]

Thank you

 

[Chris 8603]

Blue devil flush is the best I've seen for flush lately, but it won't cut that from the radiator good enough. Like someone else mentioned, that's electrolysis crystal if there ever has been. Check every ground and add some if needed. If your water pump is that noisy and not leaking, you probably have a bad impeller or those crystal built up around it. The only other thing that you might want to check is your hoses because it will eat those too if it is truly electrolysis, and head gaskets. Something else that could have happened is someone in the past used water that had a high mineral content that has caused a mineral buld up. I used to cringe watching someone dip creek water to add to a machine!!! When you get the radiator and system cleaned and well flushed, use distilled water to refill with, your supposed to anyway. Then use good ole ethylene glycol antifreeze back (aka the green stuff) and it would be a good idea since you've had issues to run wix cool additive or something similar. Not the hyer cool and super cool stiff. It helps keep deposit from sticking to metal surfaces and protect metal

 

[haymaker]

Thank you

Did this issue ever get solved. I would appreciate a follow-up for future reference please.