Removed and cleaned Boat carbs

[Ready_fire_aim]

There are many liquids that work here is a link to guys that power their injectors during cleaning.
https://www.ls1lt1.com/threads/fuel-injector-cleaning.89818/


I have a 70 Mercury oil injected engine that is a 1998 and no issues with the oil injection part of it.

Now if you ever run it out of oil you are screwed.
There is a gear on the crank that is made of steel and spins a "plastic" gear that drives the oil pump.
If you run out of oil the lube is not in the engine and it gets hot and melts the plastic gear and no more oil injection.

I rebuilt a V6 inboard jet drive 2 stroke mercury engine that was ran out of oil.
Scored a cylinder buck luck for the girls that owned the boat just 1 cylinder.

That was not a fun job.
It did not take them a month to return with the same issue because they did not fill the oil container and ran multiple tanks of straight gasoline through it.

I did not fix it again.

In the Mercury shop manual it stated to mix 50:1 oil in the fuel and have the oil injection tank full and run the rebuilt engine on that for 10 hours.
Buddy did just that no issues.

I guess Mercury does not trust the oil injection either.

Extra oil in a 2 stroke makes them run lean.

I have NEVER ran a 2 stroke out of fuel. IN the mercury manual from 1969 it states DO NOT pull the fuel line and run the engine out of fuel.

This will starve the engine of oil and you will have an engine that sits dry and can rust.

The proper way is to remove the bowl screws and let the fuel drain from the carbs.
On my 1975 mercury 50 hp 2 stroke I have always ran 100% gas and Quicksilver oil and never ran it out of fuel and I do not pull the fuel bowl plugs either and those carbs are spotless and run excellent every time I take it out.

Go figure.

Good info. I’ve got a boat with a 1987 3cylinder Yamaha 2 stroke that I’m fixing up. About to replace the steering cable and helm, among other things

The ole Yamaha has low hours and absolutely rips! I also read that these Yamaha oil injection systems worked well and most folks leave it be.

Interesting take on the whole running it out gas thing too. I was torn about that. On my newer mercury 4 stroke I’ll pull the line and run dry if i know it’ll sit for a month or more. On my 2stroke I’ve been leaving it but making a point to fire it up on the muffs once a month so it stays fresh

 

[Shadowrider]

That bucket of super smelly black stuff they call carburetor cleaner will do a good job if you can still buy it. I want to clean some fuel injectors with a ultrasonic cleaner. What is the best cleaning solution?

I used plain old simple green on a generator carb. I gave it a very quick shot of B12 before hand to knock off the heavy stuff. Like really quick, no messing with spraying every passage or anything as the can was dang near empty.

Then 90% water and 10% simple green and it came out of the ultrasonic cleaner looking like new. I'm now convinced that an ultrasonic cleaner is the only way to go for cleaning a carb. They work fantastic for that.

 

[StLPro2A]

I was wishing the soaking I gave that pontoon boat engine would clean stuff from the carbs.

Soaking involved starting it on fresh 2 stroke mix and letting it run ..It would not idle unless I kept choking it.

But I got gas through it and in the bowls.
A few weeks of soaking and then firing it back up did NOTHING.

I found hard black crud in the bottom of the fuel bowls and the main jets .072" were completely clogged with hard black crud.
Emulsion tubes clogged with hard and some gooey black crud.

Air passages clogged in some places.
2.5 hours of hand cleaning and poking holes clean with wire and torch tip cleaners and spraying mineral spirits through everything and they are now clean.

Waiting on a gasket set for them so i can finish up the job.
I bet it runs very well when I get these back on as they cleaned up really nice.

Recently removed and cleaned my kayak paddle. Works so much smoother now......

 

[swampratt]

Kayak paddle must have looked like the underside of this boat
Darn barnacles.

 

[AKmoose]

Never ran the carbs dry on a Merc 150 V6, just planned on cleaning the carbs before the 1st time out every year.