2005 yama f250 thermostat change

[wavetamer]

finally got the parts together to attempt the stat change, is there any good on line info in case I get into trouble during the install. looks fairly straight forward just have to remove some gear to get at them. any help would be greatly appreciated

[wavetamer]

*** not that easy to get at , trying to find pictures , my manual is not here yet . any one have any info or help would be great

[wavetamer]

well I did it wasn't that bad, just took a bit to get the confidence up. on a positive note both stats needed to be replaced

[scottod17]

T-stat

well I did it wasn't that bad, just took a bit to get the confidence up. on a positive note both stats needed to be replaced

any chance you could explain where and how you did them? and how do you know if they are going bad?

[TownsendsFJR1300]

any chance you could explain where and how you did them? and how do you know if they are going bad?

Their bad if their stuck open or if you test them per the manual in a pot of water-heated. If it doesn't open at the correct temp, it's failed... If the engine overheats, they may have failed and stuck shut.

As a side note, I recently checked mine manually (The computer ((YDS)) showed it operating properly-temp rise and stabilize). It was fully closed when removed but looked like crap. It was replaced (as it was 11 years old as well).

The actual replacement is very easy. Three bolts, yank the cover, pull the stat.

After seeing how the thermostat looked, I checked and replaced the external anodes (one wasn't bad at all, the lowest anode-the worst).

You can peek inside and get an idea about internal salt build up, corrosion.

An air compressor can blow out chunks of salt so it doesn't clog up anything...

[fairdeal]

The actual replacement is very easy. Three bolts, yank the cover, pull the stat.

ha yes - on the F150 and smaller, a beautiful thing.

V-6, not so quick to get at...

[TownsendsFJR1300]

ha yes - on the F150 and smaller, a beautiful thing.

V-6, not so quick to get at...

And ONLY ONE!!

[oldmako69]

I just bought four.

Will pull them all and insert the new ones, then test the old just to see if my engines are 'making oil' as a result of them being out of spec.

[pstephens46]

I just bought four.

Will pull them all and insert the new ones, then test the old just to see if my engines are 'making oil' as a result of them being out of spec.

Oldmako: Did you mention a issue with making oil?

[oldmako69]

Well, sorta. Maybe.

Bought it late Aug last year and noticed too much in the crankcase. Oil looked fresh, but having read about fuel dilution due to stuck thermostats I changed it anyway just to start a reference point with the boat.

At this point, I've only put about 25 hours or so on it, so I'm not too sure.

Here's what I don't understand. I walk up to the boat with the engines in the down position and pull the stick. The oil reads 'X'. I wipe the stick and reinsert, and pull again to check. Oil reads 'X' PLUS about two inches. I do it all over again and wait a minute before I reinsert the stick (thinking I have wicked oil up into the tube - and allowing it to drain) and I get a different reading.

So, I figure that walking up and checkin the oil after it's been sitting for a few days is the most accurate method.

Hopefully, new thermos will in fact be needed and things will settle down.

[rodbolt17]

to CORRECTLY check the oil requires two things.
1 is to trim the engine up for at least 5 min.
2 is to trim the engine back to level and remove the dipstick then reinsert the dip stick.

[fairdeal]

trim the engine back to level and remove the dipstick then reinsert the dip stick.

"holy crap there's no oil at all - oh never mind"

I've said more than once....

[oldmako69]

Thank you. I was unaware that I first needed to tilt the engine UP. Seems a tad counterintuitive given the permanence and absolute of gravity and the location of the dipstick. As in many things, I am an expert on how to do them incorrectly. I must have missed the correct procedure during my brief and obviously inadequate perusal of the owners manual. Probably missed a whole bunch more as I was tippling when I read it. Still bemused at how an engine at rest can suddenly read significantly different than it did five minutes before given that it remained in the down position. I'll not make that mistake again so hopefully my bemusement shall ebb. You can lead a horse's ass to a Yamaha, but you can't ensure that he will accurately asses the engines oil content without a good kick in the pants.

I sure hope that I have better luck replacing the T-Stats, the fuel lines and pulling the Injectors for reman. Otherwise, this could be a long and dry boating season.

"How 'bout them thermostats!" and, "Why were the plugs SO damn tight?"

[TownsendsFJR1300]

Tilting the engine get's all the oil that settles in the nooks and crannies(towards the rear of the engine) back into the crankcase for an accurate reading.

Some folks(not often), will get a puff of smoke on start up with oil sneaking up the cylinder with the engine tilted in FULLY..