cummins bc vs. cat

You hear about it more because they operated at higher temperatures to begin with so when something went wrong it was more likely to be catastrophic then if it happened to a high flow engine.

 

This is the 1986 Big Cam 4 I am going through at this time. Notice the deformed aftercooler? This is low flow, but it won't be when I'm finished, and it won't be stock neither, I'll just leave it at that.... It is suppose to have only around 10,000 miles on it and so far, everything I have looked at from the rear main bearing, to the heads, to pulling #6 piston says the mileage is correct on the in-frame. Everything looks brand new, and is all Cummins parts. Enough about my junk .

 

Didn't the BC 4 also have a reverse flow ? I can't seem to remember. I had or should I say, I still have my 1979 K-100 and its a BC 1 (cpl 369) but its been parked. I never seem to be comfortable with the low oil pressure on the BC's 2, 3, and 4.

 

Had a different flow through the radiator than the Hi-flow. Hi-flow is a normal setup, coolant in the engine is pushed into the top tank of the radiator, then runs through "all' the tubes to the bottom...one direction... then leaves the bottom tank of radiator and back to the water pump. Low-flo actually flows back and forth from top to bottom back to the top and back to the bottom all across the radiator, and the lines are a lot smaller. So if you change it out from Lo-flo to Hi-flo you also need to change the radiator.

 

You need some paint on that block. Gotta make it look like it only has 10k miles on it.

 

LOL... Oh yes, when I'm done it will look all brand new. I was told it had been used for about 10,000 miles after the in-frame then parked for little over a year. Just covering all bases before it goes in the frame rails.

 

My brother has a'89 444 Cummins with low flow cooling system. After all the trouble he has had with it he should have changed it over to the high flow even though it was not cranked up because of the age old saying keep it simple. Also it is hard to find someone who has any experience with system. He had the rad out twice before he found a rad shop that understood system and made sure baffles in tanks were sealed well but even then he still had cooling issues at low speeds. I think the low flow system was Cummins attempt at getting better fuel milage. The belt that runs the water pump and water pump is tiny compared to my 400 BC3.

 

Just keep in mind, there is more to changing from low flow to high flow than what you see on the outside.

 

If you want to spend lots of time wrenching. Get a bc. If you wanna go to work and not worry get a 3406. Just from personal experience