Help pressure testing aftercooler

[Bob Bradley]

I've got my aftercooler and heat exchanger cores out for a cleaning and I'd like to pressure test them while they're out. I need to block off one end, and also block the other end, but also be able to pressurize it. I'm sure there's a simple solution out there, so before I reinvent a wheel I thought I'd ask the smartest bunch of guys I know. The rest of you can just ignore this. You know who you are.

 

[Captain Ralph]

google; plumbers test plugs
Just remember very low (2psi) low pressure.

By the time you prep and do all of this, A radiator shop would already done it for a better price.

 

[rsmith]

If your not losing coolant now just clean them and visually inspect them. The more handling the more chance for damage. I had my heat exchangers out to clean once I had read somewhere they should be pressure tested. I made up a rig and pumped them up to 5 psi (remember the cap is 12-15 somewhere in there. After 24 hours there was a slight damp spot at one of the welds. Mine are monel. Never dripped or post pressure but you could see it spread from probably some porosity in the weld. Most likely had been that way for 30 years since it was made. I can but monel is tricky. So I take it to an “expurt” that does marine exhaust and specialized fabrication. The more they welded it the worse it got until they overhe the metal so bad a crack opened up. Their recommendation smear it up with KPoxy or JB Weld. That did work either. So after 2 months of the boat being down and missing some of the best Blue marlin bite off Walkers Cay in 10 years I finally located a new takeoff from a tug on the Mississippi that went with a keel cooler. $5k it cost me for something I should have left alone in the first place.

 

[drburke]

... I thought I'd ask the smartest bunch of guys I know. The rest of you can just ignore this. You know who you are.

Bob, this may the the funniest thing I see today, and I am still pondering it.

If one answers, they must be in Group 1, but if you ignore it, then Group 2.

But if I don't know which group, then I must be Group 1 since Group 2 knows who they are...ahh, f*ck it I'm having a cocktail.

DAN

 

[Bob Bradley]

I might have already had one before I posted it Dam

I don't trust radiator shops to not damage it. I had my DD aftercooler fins all flattened by some monkey with a power washer at a radiator shop several years ago.

And, it's raw salt water that would be leaking into my engine, so I want to be certain before I reassemble them.

 

[Avenger]

I would test them assembled. It's usually much easier to plug hose ports than to cap the ends of tubestacks. The threaded hole for a zinc is a great place to attach a regulated air supply. Also, by doing them assembled you check the seals as well as the cores.

 

[Captain Ralph]

Before you get carried aweigh with all of this? Do you have a problem? Or think you have a problem??
What problem do you think you have??

Never kick a sleeping dawg..

 

[Bob Bradley]

This is a purely PM project. The Cummins QSM11 can be susceptible to badly clogged aftercoolers, usually caused by exhaust leaks. The recommended service interval is 5 years, but the previous owner never tore it down in the 6 or 7 he had it, and did not know when it had been done previously.
If the aftercooler were to fail to the point it leaked, then salt water would pour into the guts of the engine, basically destroying it. This is the motivation to do the job. I simply had to see with my own eyes what sort of shape it is in. And, since I've already got 50 or 60 hours into the teardown of both engines, it seemed prudent to test what I can while its open. I have a friend with the same engines, and here's what he found on his <600 hour engines (mine have 3200hrs).




I was pleased to find that mine looked more like this...


That's the top side, where the air come out of the aftercooler. The bottom, where the air from the turbo goes in, was oilier, but nowhere near clogged. I could shine a flashlight clear through the unit. That said, I still want to verify that it's sound.

 

[rsmith]

After seen them I’d definitely want a pressure test but like Scroddy said you can do it when you put it back together. I had a coolant leak and found the injector tubes leaked into the cylinders. I used a SnapOn radiator pressure tester. I’ve heard enough bad stuff about these and Cat raw water intercoolers that I’d be looking for a good used set to sit on the shelf. The season is short up there nothing worse than losing an entire season.

 

[SeaEric]

This is a purely PM project. The Cummins QSM11 can be susceptible to badly clogged aftercoolers, usually caused by exhaust leaks. The recommended service interval is 5 years, but the previous owner never tore it down in the 6 or 7 he had it, and did not know when it had been done previously.

I have an old invoice in my file that says aftercooler service was performed in 2014.

 

[Bob Bradley]

I have an old invoice in my file that says aftercooler service was performed in 2014.

I'm a little confused. Are you saying you have an invoice referring to my present boat's QSM's?

 

[brettportzer]

Do you have any records for my boat too?

I'm a little confused. Are you saying you have an invoice referring to my present boat's QSM's?

I have an old invoice in my file that says aftercooler service was performed in 2014.

 

[SeaEric]

I'm a little confused. Are you saying you have an invoice referring to my present boat's QSM's?

That's what I'm saying. I also have the invoice from when they were installed in your boat new.

 

[SeaEric]

Do you have any records for my boat too?

Had "Cousin" Ron listed the boat with me I probably would have.

 

[Bob Bradley]

Not sure we're talking about the same boat. I bought "Win Mag" from a guy named Jake in NC. Boat was formerly named Jolly Mon.

 

[SeaEric]

Not sure we're talking about the same boat. I bought "Win Mag" from a guy named Jake in NC. Boat was formerly named Jolly Mon.

Maybe you're right. You certainly can't trust what some random, idiot yacht broker says on the internet. Gee, I'm getting almost as cranky as Captain Ralphie!

EDIT: 02042022 Dropbox link to referenced repair invoice removed.

 

[brettportzer]

Had "Cousin" Ron listed the boat with me I probably would have.

I got a lot more info with this boat than lots of people get, that is for sure.

 

[Captain Ralph]

I'm getting almost as cranky as Captain Ralphie!

Not yet my friend. It takes years of tude to get this cranky.
Thanks for the thoughts,
Stay well and safe my friend
rc