Somebody Explain this to me Re: T-Stats Question

[pstephens46]

I use Postimage: https://postimg.cc/gallery/fhfLnzg

It's free to use. Upload your pictures there (to your acct), then copy and paste the "hot link for forums"

Your picture will then post, IE:

I recall using Post Image site after you mentioned it.

[TownsendsFJR1300]

...Duplicate ...

[TownsendsFJR1300]

. Any tricks to this other than using another site?

I use Postimage: https://postimg.cc/gallery/fhfLnzg

It's free to use. Upload your pictures there (to your acct), then copy and paste the "hot link for forums"

Your picture will then post, IE:

[pstephens46]

The first pic is shows the old corrosion I discovered back when Fairdeal was posting about his F225. I had one more spot after that but the discussion was the gunk build up on frame of thermostat gave connectivity between bronze and aluminum. The two metals don’t get along and pitting occurs. I haven’t had any new spots since coating. The second pic has old on left, new stat on right.

In response to OP, we run from spot to spot when fishing. Motor, of course, on-off-on, repeatedly. Anyhow, thought I would add to thread with results of a test. Shocked the flex seal didn’t flake off. I did prep throughly with sanding prior to coating.

[pstephens46]

Next photo to follow. I had to crop the photos to duck under the size limit of 2 mb. Any tricks to this other than using another site?

[pstephens46]

Finally got around to replacing the one thermostat on my F150 last night. I’m going to try to post pics directly from phone. We used to have to use the silly photobucket site.

[BQUICK]

I only flush at end of season (with SaltAway solution) but when I do I remove thermostats......

[HMBJack]

I am the Original Post guy for this.

This is a very long and very old thread.

Fast forward to today, what I learned is my crappy T-Stat bores (in photo on post one way above) was due to the previous owner of my boat NEVER ONCE flushing the engines in any way.

I bought the boat with 312 hours. And the previous Owner had it for 4 years. No flushing IMHO. So - I inherited salty T-Stat bores.

In my thousands of hours of use since 2010, I have learned the key to flushing a Yamaha, or any outboard for that matter, is to flush it immediately when you turn off the motor.

No Salt Away, no Vinegar, no muffs, no water tank - just flush it with FW while the engine is still HOT.

Since doing this, when I inspect my T-Stats after one or two years, they look perfect.

I wet slip my boat so this is easy to do when I return from a trip. I connect the FW flush hose practically before I tie my boat to the dock.
But I swear, what I'm saying here is true. Over and over again, my T-Stats look perfect after 100% repeated flushing when the engines are HOT.

Not sure what I'd do if I trailered my boat.
By the time the boat gets up on the trailer, the powerhead will cool down thus making a flush ineffective (or at least less effective) since the T-Stats will close up.

[pstephens46]

I went back and read this entire thread again. Very entertaining. So I coated the body or shoulders of the brass thermostat on my F-150 with Flex Seal. Yes, the stupid commercials on TV. About 4 years ago. I was having major pitting in the bore. I’m replacing for the first time tomorrow. Inspected many times in the last 4 years and no new corrosion. OP had a great idea.

[HMBJack]

I’ve owned 3 F225’s and 2 F250’s for a collective 2,300 hours of use by me personally and I have never experience a stall at idle.
No worries on a thread de-rail. I think we’re all curious.

[boscoe99]

You forgot,

3. The stalling at idle issue.

Yes, what is the stalling issue about? Have not heard of this one.

[boscoe99]

I can see a thermostat modification being desirable for some motors in some applications. A motor running in salt water that is nominally 75 degrees is going to be different from a motor running in fresh water at 40 degrees. I suspect motor designs (and maintenance plans) are structured for average use in average conditions. One size might not fit all.

[HMBJack]

Old Mako

I haven’t heard of that one. What’s the fix?

[oldmako69]

You forgot,

3. The stalling at idle issue.

[HMBJack]

The only issues with the 3.3L V6's are:

1, The Dry Exhaust Manifolds - which you can fix with your MasterCard or Visa with your Yamaha Mechanic, and
2. The Thermostat bores . This post - if you read every page - will educate you on that. Drilling holes in your T-stats is not a bad thing. You for sure get more FW flush water passing through your T-Stat bores. In my case I have decent water pressure at my slip. But to be very sure, when I can, I now flush with the muffs+ the garden hose fitting. I am very very sure I am flushing my T-Stat bores better than before.