Hose ballooning at aftercooler

[Jeff Lewin]

Went for a 2nd sea trial after completeing a aftercooler, heat exchanger , impeller service, Port engine hose at aftercooler looked like it was going to explode at 2000 rpm starboard side perfect… Does that hose have pressure, i know mechanic used a regular radiator hose

Topic

[Edwin Harvie]

I installed an outboard-style water pressure gauge to monitor impeller condition, but should also indicate any plugging trends in the system. Runs about 5-6 psi at cruise.

raw water alarm options

[Rob Schepis]

As to your question about temperatures being an indicator of seawater circuit blockage:

I took those above two 6BTA fuel cooler hose pictures that Tony posted yesterday when I surveyed a boat. There was clearly blockage in the seawater circuit but the temperatures held okay until she was pushed to near WOT rpms.

And another example – a Yanmar 6LP blew the hose that comes out of the pump and connects to the fuel cooler. I told the owner you have blockage. He said, he did not think so because his temps were fine even up to WOT. I put a pressure gauge on the first zinc port in the circuit – the intercooler. She hit almost 40psi and the hose into the intercooler blew up like a balloon. He was no longer in denial. We did a quick flush with barnacle buster but excluded the intercooler as I did not want to take a chance in case the o-rings were seeping as it was overdue for bench service. The descale flush was just to get him good to finish the last 6 weeks of the season. After the flush pressure at that same port dropped to 17psi max at WOT. he finished the season and that winter ALL coolers hit the bench for full service.

Real examples that temperature creep or no creep cannot be the deciding factor as to what is going on inside your seawater coolers.

[Tony Athens]

You have not really posted a good pic of the “bulging” hose to gauge much, but when things are CLEAR and clean of all obstructions, the hoses to not bulge even at higher rpms.. This can all be checked at the dock in neutral.

Yes, you could have a bad hose, so why not change them all and see what happens.. The ultimate test is a 0-30 PSI gauge on the test port on the pump.

[Jeff Lewin]

Tony Athens wrote:

You are not really answering this question directly———————-Tell me what “servicing” really consisted of..

<strong class=”gdbbx-bbcode-bold”>When was the last time the aftercooler was on the bench and all taken apart?

Did YOU see the servicing of the core, housing, etc etc etc?

How about the gear cooler core and HX core?

Tony… Thank you .. He took both coolers off, and apart, the port came out very easy, he had them cleaned out and new seal kit and reinstalled them… he said he also took apart the HX, but i did not see any pics of that being done.. I did not verify water output, but ran right at 180 degrees, no blow by, no smoke,
Would a reg radiator hose be the culprit, I didn’t think the 15psi is very much
if there was a restriction, wouln’dt the temp reflect some water flow problems?
I’m trying to get the owner just to give me a credit and get my own certified mechanic to look at it

[Jeff Lewin]

Dan wrote:

”after completeing a aftercooler, heat exchanger , impeller service”<em class=”gdbbx-bbcode-italic”><strong class=”gdbbx-bbcode-bold”>{content}[/I]

If it didnt do it prior perhaps the mechanic left a rag stuffed inside one of the ports after servicing?

it did do the exact same thing, the first time before the service

[Tony Athens]

You are not really answering this question directly———————-Tell me what “servicing” really consisted of..

When was the last time the aftercooler was on the bench and all taken apart?

Did YOU see the servicing of the core, housing, etc etc etc?

How about the gear cooler core and HX core?

[firehoser75]

Jeff,
The clog, blockage, or partial blockage must be in the raw water path after the raw water pump, most likely after the fuel cooler. It could occur in any of the hoses or in the aftercooler (bottom cap), or the aftercooler internal water pasages, in the internal gear oil cooler passages (or the water input end), in the heat exchanger passages or water input end, or possibly in the exhaust elbow (beyond?).
Usual culprits for causing a problem are impeller pieces (often getting caught in the bottom of the aftercooler but sometimes getting further), zinc pieces from dissolving anodes (anywhere a zinc is installed or beyond), or debris build up from seawater (calcium). Since this occurred after servicing, Dan’s “stuffed rag” idea bears looking into as well.
Take the anodes out and try to look inside with a flashlight. Take off some hoses near the “best guess” locations (input ends of the various components), and go from there. If needed, you may need to take the HX and aftercooler apart to ensure no problems there, Rod out the water passages, etc., but that is the last thing I would do if finding nothing else. As Tony asked (and you have not mentioned) when was the aftercooler last totally serviced? That could be a problem if it was not done with the other items.
Good luck

[Dan]

”after completeing a aftercooler, heat exchanger , impeller service”{content}[/I]

If it didnt do it prior perhaps the mechanic left a rag stuffed inside one of the ports after servicing?

[Jeff Lewin]

Would there be any other places to look for a clog

[firehoser75]

Jeff,
There should only be about 15 psi in the raw water hoses, so quite low pressure. My thoughts are that either that hose is not capable of that pressure, or is faulty, or you have a blockage (partial) somewhere downstream creating this situation?? Just my thoughts, but I am not expert, so listen to Tony, Rob, etc.

[Tony Athens]

Something is clogged either in the aftercooler or after it..

When was the last time the aftercooler was on the bench and all taken apart?

Gear cooler * heat=X ??

A clogged seawater system lead to “BULGING HOSES” with excessive pressure from the seawater pump

[Author]

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