help with Katz coolant heater install

[ugly greasanova]

I did some searching on here and found out (i think) where and how to install the Katz coolant heater...

I plumbed it into the drain plug on the radiator, mounted it right next to that inside the frame rail (i guess that's what it's called..??) and then plumbed it into the hose coming out of the block and going into the heater core (with a brass T ).

I have it plumbed with flow direction arrows on the Katz pointing away from the radiator and toward the block...is this right?

The reason I as is b/c even though the hoses are hot when I plug it in, the engine is not any warmer. I recently installed a temp gauge with the sender right in the block directly above where all the belts come together. there was a square style bolt right there, I just unscrewed it and screwed in the sender. I guess this is a good place to get an accurate engine temp reading?

so i guess my question is why isnt the Katz heater getting the engine warm? I've had it plugged up for up to 8 hours trying to see whats going on. My only experience with coolant heaters is one that I have on my VW and it gets the engine good an hot after a couple of hours...

thanks!

[Joe Mc]

Some information on the truck such as the year would be helpful. Some photos and information on the aftermarket heater would also increase your chances of getting some help, Katz makes a lot of different heaters.

[CDX825]

Coolant flow may be restricted some how. These type of heaters work off of the idea of a thermo siphon. So the idea is that as the coolant in the unit is heated it should rise to the top of the engine and the cool coolant will enter the unit and be heated and rise the cycle will continue. I have a similar heater made by zero start. It came with the directions witch apply to all of these type of heaters and it shows the heater input being level exactly with in your case the radiator drain plug and the hose run nice and straight out of the top of the unit to the top of the engine. So basically when the coolant is hot it only has one way up to go. If you mount it lower than where you are geting the coolant from it will try to flow up both ways and the system will not work. In my opinion these things should have a pump built in to help out. I have not installed mine yet as Im waiting till fall. It requires removing one of the drain plugs from the block. Im sure that will be interesting as they probly have not been removed since they were put in.

[ugly greasanova]

oh yeah...

87 F250 6.9

that makes sense about the heater being level with the input....i'll give that a shot

thank you!

[Kaliburz]

Yup.

When using tank type external heaters, mounting is important. The heater should be just a little be lower then the source of the incoming water. In this case, your drain plug off the radiator. The outlet should be the same level, if not higher. As you indicated, it's going to the block.... do you mean the water pump or a head connection? (I've only seen the 7.3L IDI hoses, so not sure how the 6.9 ran things). Diagrams I've seen show you are not suppose to have any bends in the return line. How close to the block did you T into? Was it w/in 6-9 inches?

One small thing bothers me about your install. The source is on one side of the thermostat while the outlet is on the other. Is it possible the thermostat itself is stopping the flow? Normally, if one were to get coolant as a source, it would be a drain plug on the block. Normally that is where you tap into- keeping the heater itself lower.

I've plumbed in two tank type heaters so far. Both have worked perfectly. That is why I prefer them over the lower radiator hose type.... as those, in my experience, seem to heat the radiator more then the block!

[Mr_Roboto]

I've never had one of those tank heaters work right. Never had a problem with the ones that go in the lower radiator hose, you just have to make sure it is placed where the heat will rise into the motor.