Raw water in the coolant tank.

My perkins T6.354 was running a little hot, about 195, up from the usual 180.

The strainer was clear, the impeller was good. Today I ran some Rydlyme through the raw water side. While I was doing this I also changed the thermostat. To change the thermostat I drained the coolant from the tank. It was green and looked good.

I also got a new 7lb coolant tank cap. The cap was not on the tank while the rydlyme was running.

After a while I noticed the rydlyme/water mixture in the bucket was about one gallon lower than when I started. I looked in the coolant tank and it was almost full. I put the cap back on the tank and continued to run the Rydlyme. The tank did not overflow.

When I finished with the Rydlyme I did a flush with fresh water, put the impeller back in, and hooked up all the hoses.

I also emptied the coolant tank again. This time is was not nice green coolant but somewhat like a light brown water.

I have not refilled the coolant tank and have not run the engine.

I am thinking I have a heat exchanger problem that has let raw water into the closed coolant side.

Any suggestions on what I should do next, or if I did something wrong when I was flushing the raw water side?

How did you plumb the Rydlyme through your system (connection points and type of pump)?

I took out the impeller and ran it from just before the raw water strainer to go in and out just before it goes to the exhaust elbow. I used a low pressure pump supplied by Rydlyme.

GreySky may be on to something, but you still have acid in the coolant side and you need to get that out NOW. Drain all you can, fill with fresh water, run the engine until the thermostat opens, drain and do it again and again. Then fill with 50/50 coolant.

Then if it isn't a plumbing problem that let the acid get into the coolant, test the coolant system by pressurizing it with a kit you can borrow from most auto parts stores. Odds are you have a big leak in the raw water heat exchanger.

You probably have the so called multi cooler which combines the exhaust manifold and main heat exchanger. It won't be cheap to replace as it is likely to be more than just the tube bundle (stack). Talk to Trans Atlantic Diesel.

Edit after reading above OP's response: That is the right way to hook up an acid flush circuit. So your problem is likely a leak and not a plumbing error.

David

JD

Contrary to popular belief, the best way to clean a heat exchanger is to remove it and either soak it, manually rod it out or put it in an ultrasonic cleaner. Then pressure test it at 5 to 7 psi. To confirm David's question, what kind and type of heat exchanger?

On engine acid cleaning can lead to a variety of issues including eating away non compatible cooler solders and weldments. Suggest after a good rinse job you remove and pressure test the heat exchanger.

Cracks in HEs may well pressure test okay with just air or ambient cool temp water.... Suggest use very hot water to test for leak. Have to get metal hot. Cracks close when cool.

You probably have the so called multi cooler which combines the exhaust manifold and main heat exchanger. It won't be cheap to replace as it is likely to be more than just the tube bundle (stack). Talk to Trans Atlantic Diesel.

Click to expand...

If he has original power, he does not have the multicooler.
It should be a standard heat exchanger.

I already used at least 5 galons of coolant and I don’t know where, maybe leaking.
I already chamged the caps in my Cat 3208, but in the morning the coolant gone.
I decide to use water.

I’m cruising from St Maarten to Ft Myers, passing now in San Juan , P Rico

I’ll mix 25% of coolant and 75% of water

Don't forget to check the oil! Your coolant could be there (head gasket), or (hopefully) out the exhaust.

Thanks for the advise, I check the level and quality of the oil every day. [emoji6]

I am confused... the OP stated that coolant and tank level was fine before treatment. He likely would have had overflow if there was a preexisting head gasket leak (and the coolant would not have been green).

I once had some sea water enter my freshwater side because of those stupid little "boots" on my Volvo MD2030. It is a common problem--if they are not installed perfectly, you will have sea water enter your exchanger.

Any updates jdud133?