Possible cooling system problems

[islandstyle57]

Wow, I am feeling a little better now, or maybe a little worse for you. Your high temp on your port engine is about 10 degrees warmer than mine, and you are running in fresh water, so salt build up would not be a problem. I am also assuming you never got a high temp light or a reduction in rpm's, so maybe my problem just got a little more palatable and I could just have a greedy dealership looking for work.
However, I am still going to pursue the diagnosis as soon as my YDS arrives.

 

[buckbuck]

Great idea @Scottintexas
I'll try to do the same next time out. I do recall that mine was also warmer on number one and got cooler as I worked back.

 

[islandstyle57]

Thank you all for the advice and assistance you provided me for my overheating problem.

The last 2 weeks the Florida East Coast has been getting rain every day, the weather, along with work commitments has severely impacted my ability to work on my boat.

Here is where I stand:

I replaced the anodes, although the ones I pulled out looked to be in really good shape with minimal salt build up and/or any erosion.

I removed the thermostat and checked it on the stove top, it opens at 143F which is at the top of the scale so it is being replaced.

I have blown coolant lines out with 75 psi shop air, with little or no resistance and no signs of any salt build up or sand or muck residue coming out.

I have been flushing and overnight pickling the motor with salt away for a week, and I am starting to see signs of improvement, this without a thermostat installed to restrict flow and pathway for any contaminates to exit the cooling system.

I removed the water box (muffler) and flushed/inspected it, no signs of sand, salt, or muck build up. As a matter of fact, internally it looked very clean.

The YDS, not so much luck with that. I am having difficulty with the engine talking to the computer. I have loaded the software on 2 separate machines getting the same results, not too sure it is not the cabling. I am working it out with the individual I purchased it from.

Temperatures when I flush at idle are down, and below 190F, but as I stated, this without a thermostat installed.

Bottom line, I am seeing light at the end of the tunnel, and I am learning a lot about the boat, such as, the tow valves that the previous owner installed under the clean out tray, and the number of factory hose clamps that need to be replaced amongst other deficits that need to be dealt with after vacation.

My confidence is slowly being restored. I will continue to flush and overnight pickle the motor for another week, and install the new thermostat, and try to resolve any software/hardware issues with the YDS and let you know where I stand.

Again, special thanks to @Ilmmct @Scottintexas, @Cobra Jet Steering LLC, @buckbuck, @Evil Sports, @4x15mph, @scokill, and @Zonie for you rplies and assistance. I will keep you posted.
Greg

 

[Ilmmct]

Seams light at the end of the tunnel. Good luck getting out of the doghouse and out to the water!

 

[buckbuck]

@islandstyle57 I highly recommend you remove the tow valves and replace them with vise grips stored in your tool box. In my opinion they restrict the cooling water flow too much.

 

[islandstyle57]

@buckbuck, I was thinking along the same line. It is easier in a panic moment to reach the cooling inlet lines with the vice grips than to try to remove the hand hole covers in the back deck anyway and the flow restriction created by the inline valves certainly does not help any overheating issue.
Thanks

 

[islandstyle57]

@buckbuck, How do you feel about leaving the thermostat out? We have been doing that on Hotrods for years to aid in cooling issues.

 

[buckbuck]

I believe it is needed to stay in to provide the proper backpressure necessary to cool the exhaust manifold. Leaving it out allows water to flow through the engine easier but may not get enough cooling through the manifold. Have you checked the three holes in the exhaust pipe where the water first makes contact with the exhaust gases? Others have reported these get clogged with salt and corrosion.

 

[islandstyle57]

Just an update...We took the boat down to West Palm Beach/Singer Island last week for some snorkeling and diving. We ran out the inlet and up and down the ICW at idle speeds up and down to 10K RPMs. The hottest temp I recorded after successive runs was 180F on the number 4 (which was the suspect cylinder) with no over-temp alerts. My boat ran as well as it ever has. Yesterday after a trip in the Indian River Lagoon near the house I flushed it on the hose with Salt Away and after 10 minutes the highest temp I recorded was 174F. I believe my overheating issues may be a thing of the past. All the advice and the Salt Away have done the trick. Thanks guys, I cannot say enough!

 

[Ilmmct]

Glad to hear. Happy boating!

 

[islandstyle57]

Thanks!

 

[scokill]

Just an update...We took the boat down to West Palm Beach/Singer Island last week for some snorkeling and diving. We ran out the inlet and up and down the ICW at idle speeds up and down to 10K RPMs. The hottest temp I recorded after successive runs was 180F on the number 4 (which was the suspect cylinder) with no over-temp alerts. My boat ran as well as it ever has. Yesterday after a trip in the Indian River Lagoon near the house I flushed it on the hose with Salt Away and after 10 minutes the highest temp I recorded was 174F. I believe my overheating issues may be a thing of the past. All the advice and the Salt Away have done the trick. Thanks guys, I cannot say enough!

About 10 years of being around this forum (counting the other one too), I'm convinced there are some very dishonest dealers/mechanics and some that are perhaps not dishonest but just ignorant about these engines and default to the most expensive course of action.....either way this forum has saved folks countless thousands of dollars through the collective knowledge and experience. I'm glad your problem seems to be fixed. I would doubtful there was ever a problem.

 

[islandstyle57]

@scokill , the worst of it is, the owner of the shop/dealer I use and took my boat in for the original annual maintenance is a friend of mine.

 

[scokill]

@scokill , the worst of it is, the owner of the shop/dealer I use and took my boat in for the original annual maintenance is a friend of mine.

That was my point on perhaps not being dishonest but honestly ignorant.

 

[buckbuck]

He has to be knowledgeable about many different types of boats and engines. We tend to have very specific experience with just one type. It is hard to compete with our perspective. Don't let it effect your friendship.