Cleaning Thermostat Housing

[rodbolt17]

and I never run an F225 on the muffs.
I typically flush using the port with the engine idling.
I do my F150 the same way.
however with the engine off flush water may or may not make it to the top of the cyl head.
almost all Yamaha tell tales stay cold as the water is typically taken from a spot BEFORE it gets a chance to cool anything other than maybe a fuel cooler.

I think the older F and T 9.9/15 used a combination of T stat discharge and cold water.

[pstephens46]

May need to test this.....Pull boat at lift and put on trailer. 10 min drive back to house. Flush with flush port as soon as the boat is in driveway. Is the engine hot enough to keep stat open for a few seconds as the water flows through the port? Might this be enough?

[rodbolt17]

idle speed at about 10 min or so.
make sure you see water exiting the water intake screens BEFORE starting the motor,
use full water pressure.

[dark_star]

I would just like to confirm you are actually running the engine while
using the flush port rather than muffs ??
this goes against what I have been told in the past.

[rodbolt17]

over the years Yamaha said you could then could not.
for extended runs like decarbing I use both.
for simple runs like testing or warming it up for a test I use the flush port.
never had an issue just keep the RPM below about 1000.
been doing it that way since the latter part of the 90's.

[cpostis]

Just in case anyone is interested:
The difference between green and yellow zinc chromate paint is that the yellow does not contain uv blocking pigment, the green does (usualy called "lamp black").

[TownsendsFJR1300]

Besides flushing on muffs with engine to temp, I started using "Salt Away" which attaches between your muffs and garden hose.

Even with the slightly more limited water flow, the unit has a knob atop it so you can turn it on (add the product) without stopping the engine (thermostat is still open, engine to temp-distributed FULLY).

It may take a minute tops, but you can see what appears to be soapy water exiting the engine. Your done...

With all the corrosion / salt water issues I've seen / read here, I consider it a small investment to help avoid the corrosion issues..

Brackish/ salt water use...


IMO, even if only able to flush while in the water / tilted on the attachment, a half minute of Salt Away, certainly can't hurt...

[fairdeal]

Just in case anyone is interested:
The difference between green and yellow zinc chromate paint is that the yellow does not contain uv blocking pigment, the green does (usualy called "lamp black").

I am interested!

Before using it, read somewhere that the paints' Achilles Heel was UV, and hence required a top coat of a different product.

Wasn't worried, knowing that I was only going to use it where the sun don't shine.

but seems like the green is fine anyway.

[Jason2tpa]

Besides flushing on muffs with engine to temp, I started using "Salt Away" which attaches between your muffs and garden hose.

Even with the slightly more limited water flow, the unit has a knob atop it so you can turn it on (add the product) without stopping the engine (thermostat is still open, engine to temp-distributed FULLY).

It may take a minute tops, but you can see what appears to be soapy water exiting the engine. Your done...

With all the corrosion / salt water issues I've seen / read here, I consider it a small investment to help avoid the corrosion issues..

Brackish/ salt water use...


IMO, even if only able to flush while in the water / tilted on the attachment, a half minute of Salt Away, certainly can't hurt...

I've used Salt X with my previous engine. Its the same purpose product as Salt Away. With that engine the stat housing was vertical. I'd dilute the Salt X down, have the stat open to air and pour the solution down her throat while running engine on muffs. Then a thorough fresh water flush for 10-15min after. Stuff worked great.

[HMBJack]

I am the Original Poster and here is what my T-Stat housings (all 4) look like now after I cleaned and coated them with a coat of oil based paint:





As stated earlier, my Starboard T-Stats on each engine had 50% MORE salt crystals than the ones on the port side of the powerhead.

My boat is stored on a lift so I cannot flush with muffs. I also am reluctant to running my engine with ONLY the garden hose flush fitting at the base of the powerhead because: (1) My Owner's Manual says not to do it, and (2) I think I will prematurely wear my water pump impellor. Agreed?

Lastly, because my starboard side T-Stats were so mucked up, one thing I can do is to flush with my engines UP and slanted over to favor the Starboard side of the powerhead (i.e. helm turned all the way to the right when engines are in the raised position). If I do this, perhaps my T-Stats will stay cleaner but I still plan to inspect and clean them EACH year.

Thanks and if you have a suggestion for me and my flushing, I'm all ears...

[TownsendsFJR1300]

I've used Salt X with my previous engine. Its the same purpose product as Salt Away. With that engine the stat housing was vertical. I'd dilute the Salt X down, have the stat open to air and pour the solution down her throat while running engine on muffs. Then a thorough fresh water flush for 10-15min after. Stuff worked great.

Well that's great to know. I was told (I called Salt Away headquarters) and they said to not flush it once it was applied. This way it keeps working...

It does leave the exterior of the engine with hard water spots unless you hand dry it.

Just to clarify, once the boat hits the lift (from an outing), the garden hose hits the factory flush fitting for 10-15 minutes (not running). Then I hook up the SA and run (fresh water only) another 10 or so. Then turn on the SA until I see the soapy solution come out...


And HMB, that looks GREAT!!

Did you clean that with a chemical, water, sanding, or combination of?

I gather with a swim platform (assuming you have one) you still can't reach the LU(s) to slip muffs on?
Have you considered installing "walk about extensions" to the rear lift cross member?

[Jason2tpa]

My boat is stored on a lift so I cannot flush with muffs. I also am reluctant to running my engine with ONLY the garden hose flush fitting at the base of the powerhead because: (1) My Owner's Manual says not to do it, and (2) I think I will prematurely wear my water pump impellor. Agreed?

Those on this thread were all pretty stunned when rodbolt made this enlightened statement:

over the years Yamaha said you could then could not.
for extended runs like decarbing I use both.
for simple runs like testing or warming it up for a test I use the flush port.
never had an issue just keep the RPM below about 1000.
been doing it that way since the latter part of the 90's.

If a yam professional mechanic says it's ok, I'm good with that. Your engine so it's your call.

[Jason2tpa]

Well that's great to know. I was told (I called Salt Away headquarters) and they said to not flush it once it was applied. This way it keeps working...

If I remember correctly, Salt X stated to do the opposite. Flush with fresh water thoroughly, assuming because of how strong the chemicals are. I don't know, I just followed the directions. And yes, it did leave a whitish water stain on motor.

[TownsendsFJR1300]

If I remember correctly, Salt X stated to do the opposite. Flush with fresh water thoroughly, assuming because of how strong the chemicals are. I don't know, I just followed the directions. And yes, it did leave a whitish water stain on motor.

From Salt Away's site (I highlighted the don't flush it out part):

"Salt-Away can safely be used on all metals, fiberglass, paint, rubber, plastic, chrome, glass, concrete, brick or any surface exposed to salt. Salt-Away, mixed with water, washes away the salt then leaves a protective film on surfaces until surfaces are again exposed to water or salt. Special high-performing corrosion inhibitors in the product help protect metals from corroding if not rinsed off. Salt-Away will not strip wax or cause streaks or spots. It is easy to apply by using pressure or power washers, Salt-Away's special Mixing Unit, the ready-to-use spray bottles for smaller jobs, and by immersing items into a mixture of Salt-Away and water."

[99yam40]

I am the Original Poster and here is what my T-Stat housings (all 4) look like now after I cleaned and coated them with a coat of oil based paint:





As stated earlier, my Starboard T-Stats on each engine had 50% MORE salt crystals than the ones on the port side of the powerhead.

My boat is stored on a lift so I cannot flush with muffs. I also am reluctant to running my engine with ONLY the garden hose flush fitting at the base of the powerhead because: (1) My Owner's Manual says not to do it, and (2) I think I will prematurely wear my water pump impellor. Agreed?

Lastly, because my starboard side T-Stats were so mucked up, one thing I can do is to flush with my engines UP and slanted over to favor the Starboard side of the powerhead (i.e. helm turned all the way to the right when engines are in the raised position). If I do this, perhaps my T-Stats will stay cleaner but I still plan to inspect and clean them EACH year.

Thanks and if you have a suggestion for me and my flushing, I'm all ears...

seems like if it is on a lift you could have the motor all the way down and not tilted at all, like it normally runs.

Rodbolt is a Yamaha Master tech that has done this and still does this work on Yamahas and other motors for a living, so I would pay attention to his posts more than just someone that is not( like me)