C-12 Block Heater... Seeking Information!

[Neckster]

Well I saved myself around $200 just by looking around under the hood. I was just about ready to have a block heater installed. As I was looking around under the motor I located what appeared to be a cord for a block heater. So I followed the cord around the back side of the motor, and sure enough it was the block heater with the three prong male end. It appears that the socket was rotted away and the end just fell out and was laying behind the fuel tank.

Last night I plugged it in as it was really cold up here. I checked it this morning before I started it up. It did not appear to be warm. I checked the hoses and around the pump type thing.

Here is my main question! It appears that the block heater goes into a pump type thing on the right side of the motor. This pump thing was two valves to open or close, one on the top and one on the side, or back. What position do these valves need to be in? and what purposes to they serve? It would seem that open/close would allow the fluid to flow. Or do these valves need to be open in the winter and closed in the summer. I did not mess with them yet, as I did not know what they do. This is a CAT C-12 motor 1996.

Thanks for your help!
Neckster

[mrpersons]

neckster Most of the block heaters I've seen have been installed directly water jacket of the engine. Yours may a "add on" type where the element is contained in a seperate "can" of some sort.

I would say the valves need to open. Theres no need for a pump, as the heated water will circulate by itself. If the can itself didn't get hot, you need to check the condition of the element using an ohmeter, if thats good, make sure the cord and plugs are makeing good contact and are not broken.


You sure your not looking at a 12 volt electical type fuel heater?? Some engines with a Davco fuel filter system have them. Looks like a "can" mounted on the frame rail usually.

Good luck with your cold start adventures!

[Neckster]

I'll check it again. I will try to take a picture and post it, or a link to the picture. Thanks

[bob h]

neckster Most of the block heaters I've seen have been installed directly water jacket of the engine. Yours may a "add on" type where the element is contained in a seperate "can" of some sort.

I would say the valves need to open. Theres no need for a pump, as the heated water will circulate by itself. If the can itself didn't get hot, you need to check the condition of the element using an ohmeter, if thats good, make sure the cord and plugs are makeing good contact and are not broken.


You sure your not looking at a 12 volt electical type fuel heater?? Some engines with a Davco fuel filter system have them. Looks like a "can" mounted on the frame rail usually.

Good luck with your cold start adventures!

Block heaters are almost always installed in the water jacket (otherwise it wouldn't heat the coolant), and usually in the block. The C12 block heater is installed in the oil cooler (I think).

The valves are shut-off valves to control coolant flow to the heater core. The heater core is not required in the summer months, so many shut the valves off to keep the heat out of the cab. If your heater is working, the valves are currently open.

I would just leave them open, if you close them, you could trigger a leak.

Heated water only circulates BECAUSE of a pump... the water pump.

You don't need to ohm the heater element... here's how to check it; plug the block heater into a "known good" electrical outlet. Get a piece of tubing or pipe about 3' long (rigid pipe works better than soft wall), with both ends open. place one end against the block heater (where it plugs in), and then the other end up to your ear, if the block heater is working, you will hear fizzing/crackling noises echoing through the tube... like when you're at the beach and listenign to the sound of the ocean in a sea shell!

[Neckster]

Thanks BobH you've been real helpful. There is a filter on the bottom of what looks like some sort of pump on the right side of the motor, below the turbo. The valves were open. I did close them just fooling around, also the in-line little shut off valves on two hoses. When I started the motor and turned on the heater there was no heat, so I opened them back up and we had heat again. After dinner I'll check to see if the block heater is working by using your trick.

The motor is a 95 c-12 435 hp

Thanks
Neckster

[mrpersons]

Bob True, you can hear it working, probably w/o the pipe. But it don't work, better to grab the ohmeter and check the element to help narrow down what needs fixin, the element or the cord/connections...

Hot water from a block heater will circulate through the block w/o the use of a pump, ie rises from that point. (was what I was refering too)

U'alls have a good turkey day!!!

[bob h]

Thanks BobH you've been real helpful. There is a filter on the bottom of what looks like some sort of pump on the right side of the motor, below the turbo. The valves were open. I did close them just fooling around, also the in-line little shut off valves on two hoses. When I started the motor and turned on the heater there was no heat, so I opened them back up and we had heat again. After dinner I'll check to see if the block heater is working by using your trick.

The motor is a 95 c-12 435 hp

Thanks
Neckster

Is it a large or small filter? The large filter (abt a gallon capacilty) is oil, and the small is likely coolant.

I didn't realize the c12 has been around that long... oh, how the time flies!

Back to your original post; you said the connector was corroded? Are the terminals inside the block heater corroded/damaged? Any corroded terminals on the block heater or cord will cause current flow issues, and affect the block heater's operation.

[bob h]

Bob True, you can hear it working, probably w/o the pipe. But it don't work, better to grab the ohmeter and check the element to help narrow down what needs fixin, the element or the cord/connections...

Hot water from a block heater will circulate through the block w/o the use of a pump, ie rises from that point. (was what I was refering too)

U'alls have a good turkey day!!!

Probably NOT without the pipe... at least not with my hearing. Besides, I prefer to be sure --- try it.

[Neckster]

After dinner I tried the pipe trick and it worked. The block heater is working fine. The filter is smaller in size, and your right, it's a coolant filter, which appears to not been changed for some time as it's all oily. I should change it. The oil filter and fuel filters are located on the drivers side of the motor. Thanks for your help and advice.

Neckster

[bob h]

Bob True, you can hear it working, probably w/o the pipe. But it don't work, better to grab the ohmeter and check the element to help narrow down what needs fixin, the element or the cord/connections...

Hot water from a block heater will circulate through the block w/o the use of a pump, ie rises from that point. (was what I was refering too)

U'alls have a good turkey day!!!

Apparently it was working, best to see whether or not something is working before you start testing things for no reson.

[mrpersons]

Bob, 10-4 on that. I just wanted to try out my new ohmeter!!