Why Replace poppet and or t-stat?

[bgbird]

2006 Yama F115 4 stroke
Used in salt water but usually fresh water flushed

What is the rationale for replacing the poppet or tstat. Poppet is a mechanical valve that should have minimal wear. If no overheating is occuring why would this component need to be replaced? Same with t-stat - doesn't it either work or not?

I can understand waterpump maintenance since there is are wear issues as well as rubber flexibility and degregration issues.

 

[robert graham]

Re: Why Replace poppet and or t-stat?

My 1999 90HP Yamaha has been mostly fresh water, never had any cooling problems and never replaced poppet or thermostat, so far, so good. I did just put a new fuel pump on, just as preventive maintenance, kept the old one(which was fine), for a spare. There'll be all kinds of opinions on the subject of parts replacement, but I just try to use some good judgement on it, and with strong consideration for how boat is used and maintained. You could always buy your new poppet and thermostat and keep it on hand, if and when you need it. Good Luck!

 

[99yam40]

Re: Why Replace poppet and or t-stat?

IF you do not replace on a regular schedule at least pull, clean, and test. Look for salt build up and corrosion inside passages and lube the bolts when you put back together.

Professionals do not go through the trouble and time to clean and test because their time costs the customer more to do that than to just replace with new.

If you let it tell you it is broke it will ruin your day somewhere down the road and you may not be able to get the bolts out because of seizing or corrosion after many years.

 

[robert graham]

Re: Why Replace poppet and or t-stat?

Yep, I believe especially with salt water use, that corrosion/stuck bolts is a viable reason to at least remove, inspect, clean, or replace these items. I probably need to do mine, but like i say, I'm about 99% fresh water. Good Luck!

 

[cousinabe]

Re: Why Replace poppet and or t-stat?

I was out one day with 8 people on the boat. One of my engines had an overheat alarm an hour into the trip. We limped in on one motor to a friends house. Turned out to be the tstat was stuck closed from corrosion.

In any case, we all had to drive home in a friends car. I came back the next day with parts and was able to drive it home. It was a real pain in the ***. In hind sight, I should have just taken it out and ran without a tstat in, but I was working on the water with 8 friends watching and didn't think of it.

In any case, I inspect/clean/replace my tstats every season as a preventative maint item. I use my boat in the Cheseapeake Bay which is salt/brackish water.

 

[rodbolt]

Re: Why Replace poppet and or t-stat?

trust me the chesapeake is salt water .
why do the maint? same as airplanes have maint.
its a long swim back sometimes and these parts do fail.
trick is to replace them BEFORE they fail.