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1978 Mercury V150 Carburetor Float

D

Donewright

Regular Contributor
Greetings,

Model# WH 2

The service manual indicated that, when held upside down, the floats should pass beyond the carburetor body by 1/16 inch.

Well, i disassembled my first of three carbs and found that the floats move, but they don't get anywhere near passing the body at all.

Do you think the previous owner could have made this change intentionally, would there be any benefit ?

Wouldn't this prevent the bowls from filling up completely?

How would this affect the engine, I mean what would I expect to see as a result of this small range of motion?

The floats are 34 years old, what did they make them out of? Do you think they will crumble if I try to bend the metal tab ?

IMG_2859.jpg IMG_2860.jpg

-Thanks
 
Something sure looks wrong.-------What are the issues with running of the motor ?-----------Could these floats be mounted upside down ??--------Why not see if you can flip one of the floats over.
 
The engine won't start unless I put some pressure on the throttle cam. Just as the service manual indicated, the cam is just barely touching the roller arm in the throttle linkage. There are holes in the butterflies, so the engine should be able to start/idle when they are closed.

The floats are definitely one sided, the other side is not flat. It does match a picture in the service manual. I just can't figure out why there is a lack of movement. I suppose I can just bend the metal tab until the desired angle is reached.

I did remove one float to examine the inlet needle for an obstruction. I found nothing in there and the needle looks great for being so old. On the other hand, the gaskets in this thing are horrible. They are all melted into the mating surfaces. I have to use a razor blade to remove them. Heck, the gaskets on the High speed Jets have all but deteriorated away.

IMG_2861.jpg
 
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Something wrong there. Readjust that. I expect a high speed problem like that.
Anyway the idle circuit plate on top needs to taken off and and the pipes cleaned out to fix your problem. The bottom of the pipe narrows at the tip and gets clogged with crud.
The high speed jets might be different sizes as well.

Check the ign system, too. These was known for failing components. (the stator and switch boxes.) Maybe some of the cylinders are not hitting anymore.
 
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I appreciate the reply!

I have ordered new gasket kits and will be rebuilding all three carbs. I took the flat plate off of the carburetor and there was blackish oil/fuel in all of the little chambers (the chambers that don't have holes). The gasket below the plate is hard and it appears to be leaking into those other chambers. I ran fishing line through those pipes and can see through them when I shine a light in them.
 
Soak the carb hard parts in carb cleaner while waiting on the kits. Release the pressure on a couple of cans of spray cleaner and pour them into a metal coffee can w/the parts and cover w/the lid. The long soak will dissolve any hard varnish buildup in the idle circuits.
 
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