Vinegar Flush Help

Best advice received thus far!!! 👍🏻

Ok guys test results are in... drum roll...

Purring like a kitten on catnip!

She ran better and cooler than she has since I bought her. Took her out to Bullards Bar yesterday and checked temps using my IR gun. Temp was extremely stable at 150deg all day.

Did I fix the problem end of last season not knowing it because my faulty gauge told me otherwise? Or did replacing the circ pump, manifold and exhaust hose clear things up?

Unfortunately looks like I'm never going to know for sure what exactly caused her to overheat.

Now to have my gauge repaired.

It's his day off today

Maybe you unknowingly fixed the problem somewhere along the way or at least I hope you did since normal temps don't melt exhaust hoses etc. like what happened to you in the beginning..

I'd use an infra red gun and check temps or get a capillary tube type temp gauge and temporarily put it in place of your electrical sending unit and see what you have for readings.

Sounds like right now all you can do is run it and check temperature.

I think Bueller is getting ready to take the Ferrari for a ride right about now.

UPDATE and TEMP GUAGE HELP

Result: NO SMOKING GUN!

On the up side my cooling system looks great... down side, we couldn't find any obstructions or bad parts at all that would cause overheating. Since we were already doing a deep dive I replaced the circ pump, thermostat and impeller just in case.

WHAT WE DID FIND:
While testing the temperature sending unit he told me it was working normal but that my gauge was giving bad readings.

His test notes:
----------------
"Ran boat @ idle for 10min"
Actual        Gauge   
119               150
151               180
154               200       Stabilized, sending unit is 128.6 ohms
140 deg should be 121-147 ohms, this looks like a bad dash gauge.
----------------

Ohms and such are out of my wheelhouse so any thoughts/suggestions are appreciated as always.

Here it is, looking OK from this view, you'd probably destroy it trying to get the impeller off the shaft.

Looks a lot better than the 2 piece one in an earlier photo

I seem to be able to see the end of every impeller blade in the photo

Looks like a good spare if nothing else.

Good to hear back

Do you think you could take a picture of the internals of the original circulating pump if you still have it?

Only a handful of little bolts to take the plate off the back of it.

missing link?

Dave,

Here is the list you really need to follow:
Read the thread and follow the recommendations BEFORE YOU ORDER ANYTHING!!!

Thanks again guys... I'm just anxious to get started. The weather here won't clear up and I do not want to start this with the distraction of pouring rain and wind.

I've decided I'm going to start at the intake... check every single point for good flow, seal, blockage, cracks, failed parts etc... and work my way to the exhaust. Too much hunting and pecking has been done at this point. I'll be posting photos along the way so you all can hopefully catch any stupid human tricks I may perform.

Question: since I'll be pulling all cooling parts to check them anyway should I be replacing all of those gaskets as well along the way? Also, aside from changing out the impeller and thermostat (which are cheap anyway) are there any other parts you think I should just go ahead and replace regardless if they're in good shape or not? Sensors, pumps etc? If, for example, say the circ pumps eventually fail anyway it seems logical to just replace it while it's all opened up.
Or is that total overkill and I'd just be throwing parts at it? ;)

Gary S wrote: Good idea Ken. I had to change my Shamrocks pump due to a seal leak,a PO had used an automotive pump. Although I had no cooling symptoms or issues most of the impeller fins had rusted off from saltwater use. I doubt thats his trouble but I have heard of the impellers spinning on the shafts.

This one was an Indmar 5.7 Chevy, picture was stolen from the Mastercraft website



And here's a thread from CCF also about an Indmar but I bet they all get their circ water pumps from GM when they buy the engines from them

CCF thread

The end result of these broken impellers was overheating and there were recalls to replace pumps. Don't know about PCM issues/recalls but I bet it makes some noise if you rotate it by hand if it looks like these.

That shaft might spin smoothly with no noise and you'd actually have to take the pump off the engine and take the plate off the pump and inspect it

Hi Dave

I was thinking about your issues and one thought that popped into my head as something else to check was your circulating pump on the engine if you think your raw water pump is working as it should.

That's the circulating pump, not the raw water pump. Same belt drives both, but it would be relatively easy to remove the belt and spin the circulating pump by hand. It should spin smooth and very easy with no funny noises or wobble on the shaft.

If it had bad bearings it could have been what made your belt start fraying. If they were real bad you'd hear some metallic scraping noises.

you could check that the alternator spins free and easily too.

Like I said, just a thought and easy to check    edit I see it was mentioned on PN a while back but don't know if you checked it,

8122pbrainard wrote: KENO wrote:    But.........a chewed up impeller due to let's say, improper assembly gets worse with every revolution it makes till it's degraded to the point where it no longer is pumping enough to keep the engine or manifolds cool. And, running it dry. The impeller relies on water for a lubricate. It doesn't take much time to degrade without water. Any chance the engine was run without water even briefly?

LiquidObsession wrote: Just to clarify... when I said "chewed up" I meant it wasn't smooth anymore. It was in tact but looked as though it had been heated up... surfaces weren't smooth anymore. Perhaps it had run dry briefly.

The impeller had been run dry.

LiquidObsession wrote: So my wife and I chatted last night about this. We're "thinking about" possibly putting this on a credit card. NOT what I want to do but to be perfectly honest I'm concerned I'll only make this worse. I'm also not sure if I should use the same mechanic I've been using (he comes to the house) or go to a shop. Anyone live near Auburn Ca and/or Sacramento that has any recommendations? An honest shop that caters to the blue collar "regular guy"? Back Story: I don't have money to burn. Where other folks go on vacations during the year and ALSO go out on the boat... This boat IS our summer vacations. Boating goes back 3 generations in my family... it's in our DNA.   And my limited experiences with boat shops so far have been that they overcharge and take their time. (My experience) So one... it's extremely important for me to get this fixed. Two... I don't have the resources to have a shop spend weeks and a couple grand figuring it out. I know... then don't own a boat.

When it comes to Correct Craft boats the experts on this site are more knowledgeable than any mechanic that you will find. Let them help you by doing what they ask you to do and then provide accurate feedback. Even if you have to throw a few parts at it you will still be way ahead financially.

So my wife and I chatted last night about this. We're "thinking about" possibly putting this on a credit card. NOT what I want to do but to be perfectly honest I'm concerned I'll only make this worse. I'm also not sure if I should use the same mechanic I've been using (he comes to the house) or go to a shop. Anyone live near Auburn Ca and/or Sacramento that has any recommendations? An honest shop that caters to the blue collar "regular guy"?

Back Story: I don't have money to burn. Where other folks go on vacations during the year and ALSO go out on the boat... This boat IS our summer vacations. Boating goes back 3 generations in my family... it's in our DNA.   And my limited experiences with boat shops so far have been that they overcharge and take their time. (My experience)
So one... it's extremely important for me to get this fixed. Two... I don't have the resources to have a shop spend weeks and a couple grand figuring it out. I know... then don't own a boat.

KENO wrote:    But.........a chewed up impeller due to let's say, improper assembly gets worse with every revolution it makes till it's degraded to the point where it no longer is pumping enough to keep the engine or manifolds cool.

And, running it dry. The impeller relies on water for a lubricate. It doesn't take much time to degrade without water. Any chance the engine was run without water even briefly?