Thermostat cleaning question

[Bobcat]

Don ,
In a post last fall you mentioned(Regarding thermostat replacement.... there are plans in the works to do some videos this winter to assist in thermostat replacement. ) I was wondering if that ever happened. I know my plans from last fall didn't.
Any way when removing the thermostats from a 225 proxs(1B118939) I wanted to check on the fuel rail loosening procedure. Do I need to relieve the fuel rail pressure or just loosen the fuel rails to extract th termostats? what was the inch/lbs tightening spec for the rails?
thanks ,
Bob

[EuropeanAM]

Bob:

My apologies.... due to circumstances I could not forsee, I was unable to complete SEVERAL projects I had planned for this last winter (this being one of them).

-Relieve AIR PRESSURE at the PORT SIDE rail schrader valve FIRST.

-Remove nuts that secure fuel rails (2 per rail).

-Slide rails back as far as they will slide on the studs (you MAY need to carefully unplug the direct injectors to prevent stress to the connectors)

-Direct Injectors should REMAIN IN CYLINDER HEADS

-Utilize a 8mm socket, swivel, and extension (1/4" drive) to loosen and remove the thermostat covers

-Remove thermostat, clean as needed (or grab replacement).

-Replace gasket if damaged. Be sure to remove ALL broken or damaged gasket material

-Place thermostat in place install cover over thermostat w/gasket. HOLD DOWN while installing screws to ensure it's properly seated

-Secure thermostat cover screws to 100 INCH (yes that's INCH) pounds

-Check to ensure that NO DEBRIS is present on the direct injectors, o-rings, etc

-Apply a LIBERAL amount of 2-stroke oil (same oil you run in your oil tank) to the o-rings of the direct injectors

-Carefully slide rail back into place, and seat it over the direct injectors, depressing the rail back toward the head EVENLY

-Install rail nuts... snug down evenly, and TORQUE TO 35 FT LBS.

-Reconnect any disconnected direct injector wiring connectors

-Monitor temp after next startup to confirm you reach at least 120 degrees on Smartcraft.

* This post has been placed in the Commonly Asked-Commonly Used Sticky Post, at the top of the 3L High Performance Forum.

[Bobcat]

Thanks don,
Great post. I appreciate your time....this will be very helpful
Bob

[Stratosone]

Don:

You had given me these directions earlier and just took care of it yesterday glad I did, had some junk on the starboard thermostat. Everything went as you instructed and tested it today all is well. Thanks again for the great service that you provide us...

[BCBandit]

How difficult is this to do for an average to below average mechanically inclined person such as myself?

[Lpolk]

How difficult is this to do for an average to below average mechanically inclined person such as myself?

I'm a wire twister and I did mine a couple of times. Not hard at all, but I also bought the Service Manual when I bought the boat. It will give you pictures and step by step instructions. My suggestions is when you get a chance, get you one and it will money well spent.

[EuropeanAM]

+1... a Service Manual is a VERY wise investment. Look at it this way... if it saves you just ONE HOUR of shop labor time, it's essentially paid for ITSELF.

[TopwaterAaron]

How do you relieve the air pressure as stated in the #1?

[EuropeanAM]

Just like you would let air out of a tire: Remove the schrader valve cap, and depress the schrader valve pin.

[farmall63]

Mine is a 200 and I just took the 2 Allen head screws out that hold the Schrader valve in pulled it out . I was able to access the thermostat housing easy. Could be a later model engine is different mine is a 99 hope this helps.

[EuropeanAM]

Mine is a 200 and I just took the 2 Allen head screws out that hold the Schrader valve in pulled it out . I was able to access the thermostat housing easy. Could be a later model engine is different mine is a 99 hope this helps.

That will work... but it opens passages in the fuel rails to the possibility of contamination (or leakage)- both of which should be avoided.

[chief0902]

Found a piece of wood that had it stuck open! Thanks guys for all the help and knowledge!

[Sun Fish]

I plan to replace my stats in the spring before starting the season. Thanks for the instructions! Does not seem to hard but is there any pictures or videos available online of someone doing the job for reference?

[Mark Weare]

Having struck wood before in large lakes, leaving my stats open, I now carry a spare set of gaskets specifically for being able to clean them on the go. Although you can clean them without damaging the gaskets, if you do then you'll have more issues. When I hit that one small floater last year, I cleaned my stats 3 times that tournament day alone before I could back to the hotel to clean strainer, back flush and change lower units to clean pump later.

[Yamaholic]

Don, what is the protocol when you're on the water and need to pull a thermostat and during the process a direct injector pulls out of the head and stays attached to the fuel rail? I read somewhere that the seals will swell once removed and should be replaced with new ones utilizing the special seal installer and resizing tools. It's not uncommon for a direct injector to stay attached to the fuel rail and I don't know of anyone who carries spare sets of injector seals on the water. What do you do in this situation?

[EuropeanAM]

Don, what is the protocol when you're on the water and need to pull a thermostat and during the process a direct injector pulls out of the head and stays attached to the fuel rail? I read somewhere that the seals will swell once removed and should be replaced with new ones utilizing the special seal installer and resizing tools. It's not uncommon for a direct injector to stay attached to the fuel rail and I don't know of anyone who carries spare sets of injector seals on the water. What do you do in this situation?

In 99% of cases, you are just fine, provided you PROMPTLY reinstall the direct injector into the cylinder head (inspect o-ring for damage, of course).

The (potential) problem stems from a direct injector that's been OUT of the head for more than 30-60 seconds (the carbon dam can expand, making reinstallation quite difficult).

This is less of a problem on a COLD engine (slightly less potential of expansion).

Good question, BTW.

[BILLY]

Thanks. Good read .

[Kenny3Times]

I'm a wire twister and I did mine a couple of times. Not hard at all, but I also bought the Service Manual when I bought the boat. It will give you pictures and step by step instructions. My suggestions is when you get a chance, get you one and it will money well spent.

I searched for while to find the section on replacing thermostats. What section of the manual will I find this? My motor is a 2006 225 proxs. I have the appropriate mercury service manual.

[EuropeanAM]

Post #2 in this thread details exactly what you will need to do.

[tracer1]

Probably a stupid question but when you Relieve AIR PRESSURE at the PORT SIDE rail schrader valve FIRST, do you put air back into the valve after repair or does it build on its own? If you put air back in manually , how much? Everybody can quit laughing now.
Thanks