Raw Water flush results...

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firstbase

Guru
Joined
Nov 6, 2016
Messages
1,644
Location
United States
Vessel Name
Black Eyed Susan
Vessel Make
Grand Banks 42' Classic
Finally bit the newbie bullet and Barnacle Buster flushed out my engines...well, my port engine. Only time for one today. Ran fresh water first to check for leaks and then added the BB and WAM. It wastes no time turning the water to yuck. Ended up with a few floaties, some red paint flakes obvious a gift coming from the Ford Lehman SP135 but not sure where. Anyway, the water turned black but again not much gunk in the bottom when I dumped it out. Will do the other engine tomorrow or Tuesday. Hopefully this will solve my overheating at WOT issue. Maybe...just didn't seem THAT difrty but I don't know what I am talking about really.

My question is about what was going on after I finished. Flushed with some fresh water for a few minutes, emptied bucket and did it again. Then When I got everything back together I started the engine. Raw water flowed well but after 10 minutes or so I noticed another... something..coming out the exhaust. See pic below. No oil shean, just what looked like a slightly milkyness to the water. The pic actually makes it look worse than it appeared in real life. I have never noticed anything like this before. I guess, may be my imagination, there was a light oil type sheen but very little and it didn't seem to be directly around the milky water. Hard to see.

Anyone comment on this? Just more crap coming out after the Barnacle Buster or something else I should be worried about? Very little smoke by the way.
 

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Looks like typical Lehman exhaust to me.
 
Thanks. I was hoping so. Being a newb with no real diesel experience really sucks at times!
 
Every single one of us has been in your shoes! Learning is part of the fun.
 
To say that I appreciate all of the knowledge in here is the single biggest understatement ever made. Not sure what we did back in the day. I guess we had to be good at making friends or we sank. Probably literally!

So, the $64,000 question...what IS that in the exhaust? Lehmancrud? Fordgunk?
 
The sheen is unburnt diesel, a little oil from the cylinders and valve seals.
 
yup just raw fuel. To me, it suggests the injector pump could use a going over.

If it were me, I would take the heat exchanger end caps off and verify all the tubes are clear. If they are, swapping out the impellor will give the biggest bang for your buck when it comes to cooling. Assuming of course the hull's raw water inlet isnt choked off from growth.
 
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The unburned fuel when cold is normal or even after a days run when you throttle down and come into a marina or anchorage and the engine starts to cool a bit.

If the engine is up to temp still and you have more than a wisp now and then... could be something, but is it worth doing anything about right away is the big question.

If the injection system is high time, say more than 3000 hrs, sure try new injectors. If still a pretty good steady sheen with a hot engine, then injection pump (I dont know what in particular the pump might be doing to help produce the sheen) if you feel like it would help, but I would check first with a few Lehman experts before just sending the pump out.
 
The unburned fuel when cold is normal or even after a days run when you throttle down and come into a marina or anchorage and the engine starts to cool a bit.

If the engine is up to temp still and you have more than a wisp now and then... could be something, but is it worth doing anything about right away is the big question.

If the injection system is high time, say more than 3000 hrs, sure try new injectors. If still a pretty good steady sheen with a hot engine, then injection pump (I don't know what in particular the pump might be doing to help produce the sheen) if you feel like it would help, but I would check first with a few Lehman experts before just sending the pump out.

Thanks. This was after new impellers about a month ago and flushing with Barnacle Buster yesterday. No real sheen...MAYBE could see a slight little bit every few minutes. I have run on older 2 cycle outboards and recognize a good sheen when I see it and this wasn't it. Just the milky water. Temp wise I never got it over 150 when running it in the slip to flush out the last of the BB. I will monitor and see what it does when we get it up to temp and out and about. Not sure on PO's fuel pump or injector work. Still going over all of his old receipts.

Probably newb paranoia creeping in.
 
not to prod your hypochondria any more than necessary, but here's a short story:

I was wondering how someone could take a shower for so long, watching what I thought was milky (soapy) water coming out of the side of a boat for a couple days when it occurred to me: they must have had a pinhole leak downstream (vacuum side) of the AC pump and it was getting frothed up. this "aerated" water could be described as looking milky....
 
That's just the Lehman saying hello. Pretty much all of them do that a bit....mine included[emoji23]
 
I finished the starboard one tonight and it did the same exact thing. Live and learn or something like that. Maybe it should be post on TF and learn.....
 
yup just raw fuel. To me, it suggests the injector pump could use a going over.

If it were me, I would take the heat exchanger end caps off and verify all the tubes are clear. If they are, swapping out the impellor will give the biggest bang for your buck when it comes to cooling. Assuming of course the hull's raw water inlet isnt choked off from growth.


To my way of thinking, having a look inside the heat exchanger is a prerequisite to the use of a chemical flush.
You don't want to do that if it's not really necessary, harsh chemicals are hard on the entire system, and likely to point up any weak spots by leaking the **** all over.
There's more to water pump maintenance than just changing the impeller.
End caps, bearings and seals, cam, and even the pump body deteriorate over time.
 
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