NTC Cummins Coolant leak (pH/flush)

[zraffz]

I have a 1988 Big Cam IV 400 cummins with a minor coolant leak seaping from between the block and heads on a few cylinders. The leak is pretty minimal, some days I don't see anything other days I can see it slightly puddle on the deck of the block.

I would like to try one of those sealers such as Dike-Conklin since I see this seep seems to be a common 855 Cummins problem and this is the bandaid fix as long as no coolant is entering the oil.

My problem is I have an aftermarket coolant filter and I can't permanently bypass it because I am still running the green coolant. I have read that the sealer can't be ran through a coolant filter.


Can I flush my coolant, refill with green coolant, add the SCA additives (along with the stop leak) and bypass my filter?

Does anybody know what the pH/SCA levels of the coolant is supposed to be?

 

[DoyleX]

Why not just turn the filter off/ball valves? Crimp the line? The damage is already done, dont worry about ph now. That stop leak crap raises hell with everything else. Id just keep a couple gallons in the cab and run er.

 

[lantraxco]

Unless I'm mistaken those coolant filters aren't actually filters at all, just a solid chemical inside that keeps the ph balance correct in the coolant. You can get the test strips from Cummins or CAT along with the SCA and use that instead of the filter is my understanding.

 

[zraffz]

My filter does have some sort of valve to cut off the fluid entering the filter. I have never had to maintain one of these trucks (I am mechanically inclined with passenger vehicles) so I am not sure if the filter contains a solid or a liquid but I am under the impression it still acts as a filter based on the directions given by the stop leak company claiming it will "clog the filter".

I'm probably best off just manually adjusting the SCA levels. I had originally wanted to switch to a pre mixed SCA coolant but don't want to risk gumming up the radiator if any silicate coolant is left behind.

The leak is just annoying because if the truck is kept under a load for a long enough period of time, coolant does ocassionally contact the manifold and it drives me insane! ...but not insane enough to pull the heads to see what the problem is lol.

 

[Jonas302]

Dike had worked pretty well for us There is paper in the filters at least there was in the one that I cut open to prove there wasn't any filter in there Just change the filter later if you are concerned it will contain some additive then ask napa for a heavy duty coolant test kit part number fil 4107
and some sca additive match the colors and your good to go

 

[td25c]

I would first pull valve covers & re torque heads to (300 foot pounds )before adding the stop leak . The leak is coming from the counter bore on the sleeve . Not a big deal as noted . Looks like a major problem but it's just a little coolant coming out under the counter bore & running down the side of the block .

 

[zraffz]

Can I get to the head bolts without pulling the Jake housings off?

 

[td25c]

Yeah, sorry zraffz for my lack of detail . Should have added that .

The Jake & rocker housings will have to be removed .

This gives a little top side view of it . We were changing injectors on the dozer at a job site .
https://www.heavyequipmentforums.co...engine-repower&p=180687&viewfull=1#post180687

 

[m j]

the reason they bypass the filter when IronTiteing the block is so the filter doesnt catch the product.

 

[zraffz]

I ended up flushing the system with a hose, refilling with wet sleeve spec green antifreeze, dike stop leak and dca 4. My bypass on the filter housing was corroded and broke in the open position so I removed the filter housing, ran a tap through the weep holes and used thread sealant on two short bolts.

The new mixture defiantly took care of my problems for now. I know it is a bandaid fix but until I am working with the truck on a regular basis; it will have to do.

I have a few more odds and ends to fix up and she's off to get a clutch put into it so I can go pick up a new excavator.

 

[John C.]

It has been so long since I've been into one I don't remember for sure but I seem to recall the leaks being from O ring seals that sit in the head gaskets and not necessarily from the liner counterbores. There used to be oversize O rings for the water sides or the oil sides to correct for the wear on the block when you put new head gaskets in. The stop leak will work for a bit but not for long in my experience.