How to Decarb this specific engine (GT150)

[Stut]

I've heard a lot about decarbing, now I want to try it.

Inventory:
1) 1985 GT150
2) SeaFoam (pour can)
3) SeaFoam DEEP CREEP (spray can)

Being the overly anal and worrisome person I am, I was hoping for some direction on how EXACTALLY to do this. I have read the cans. It says:

"With engine warm, keep on high idle and spray through carburetor, or throttle body throat. If engine is port injected, use only vacuum lines that feed all cylinders. When engine is loaded up, turn off ignition. Restart engines after 5 minutes. Make sure exhaust is well ventilated as fumes will be extreme for a short time. Ideal for small engines. Use a Schraeder Valve hose attachment if needed for outboard motors. For further cleaning, use SEA FOAM MOTOR TREATMENT in tank."

However, my GT has this monsterous intake manifold (air silencer) over the three carbs.

So, do I remove this manifold so that I can spray the SeaFoam directly into the carbs, or do I just spray it into the air silencer.

Also, I have three carbs. Do I do them one at a time, following the above directions, or do I just spray into each of them as quickly as I can, then shut her off and let her sit?

Plus, there is no idication of how much is enough/too much. Isn't there a concern that I will overdo it and run a couple cyliders too lean? Basically, how long should one spray can last me (how much do I use per carb)? Is a 'decarb session' 2 minutes of continuous spraying, or is one can enough for 5 decarbs.

Can I do this while in the water? (I'm sure my neighbors aren't really happy about the sound of an unsilenced 150hp running next door...)

Any advice would be greatly appreciated!!!!

Stone

[motomania]

I dont have a specific answer for you on your questions, but I'm a bit curious myself. I'm gonna keep an eye on the thread for replys.
-
But I can say that I used Seafoam per the directions a few years ago on my car. And, if your neighbors wont be thrilled about the 150 running unsilenced, wait 'til they see what happens when the Seafoam makes it's way through a running engine! HOLY CRAP! You talk about a smokescreen!
-I'm not sure if you have mosquito problems there in Virginia, but if you do. Running Seafoam through the outboard will fumigate the neighborhood.
-
As opposed to decarbing, you could just run XD-100 through for your oil, I love it on my '86 150.


Modified by motoman at 9:39 AM 4/5/2007

[Stut]

Anyone? There's at least two of us that are interested!

Stone

[triton1cos]

on my old evinruude i would take air diflecter off and spray dirrectly into carb throats.use 5 second burst into each untill motor boggs then shut off.let sit for a while,if not been done in a long time let it sit over nite. then start it up and clear it out,if your motor has valve to hook up can with hose do it that way.hook it up and spray till it boggs.this may not be word for word as in manual but it will get-r-done.

[bardern]

I took of the air baffle and sprayed all three carbs in top to bottom order with the unit running on the ears and hose until it bogged down. Same procedure as spraying the motor up for the winter.

Will be loud and SMOKEY, neighbours may not be impressed

[kf4pfw]

I'm interested as well, I have a '78 150 SeaKing..same problems with air baffle over carbs....

Gurus.....??????

[Stut]

Triton, Barden, Thanks for the info! First hand acounts are always the best.

I will give this method a try soon. May not be for a couple of weeks since I just found out I have to go out of town.

However, I will try and be disiplined enough to report back my own experience for others.

Thanks again,

Stone

[PJCodner]

When you decarb the best way is to spray it right into the carbs. I did mine the first time through the schrader valve and I don't think it did as well as when I sprayed it right through the carbs.

I have not used Seafoam products I only use BRP stuff. They have an engine tuner that you use to decarb with. It says to spray it in with the engine running and then turn it off and let it sit for 4-6 hours or overnight. When you start it back up make sure you don't have anything behind the motor that you don't want black. It will stain everything behind the motor including asphalt. Usually what I do is take it down to the lake and go for a quick spin.

When you are done you are going to want to replace the spark plugs so if you already replaced them put the old ones back in then decarb. It will gunk up the plugs pretty good when you decarb.

If you don't want to decarb anymore you could purchase XD100 oil. It has the detergents in it to eliminate carbon buildup.