Force mid-range

[rogerwa]

I have a 1992 Force 50hp on a pontoon. I have a problem that I do not know how to fix. The symptoms are that I can run it wide open or at idle, but in between it is really rough. There is a little range on each end but it seems there is a transition point where it is firing rough and then just clears up with a little throttle. It clears up like you hit a switch and it goes into fast speed.<br /><br />I did a carb teardown this spring and I believe it started after that, although I'm not sure.. <br /><br />Any suggestions??

 

[kev_79]

Re: Force mid-range

Make sure carbs are in sync. If they aren't, this could cause them to work against each other at mid range. Well, at all ranges, but since very litte air is going in at idle, it doesn't make as much of a difference. Same with WOT, you can't tell as much since plates are pretty much wide open. Make sure settings on both carbs are the same. Good luck, tell us how it goes.

 

[rogerwa]

Re: Force mid-range

This model only has a single carb..

 

[kev_79]

Re: Force mid-range

did you replace all gaskets when you did the teardown?

 

[rogerwa]

Re: Force mid-range

It's a pretty simple carb. I replaced the mounting gasket,between the carb and intake, and the bowl gaskets. Thats all there is..<br /><br />I also drilled out the plugs to gain access to all the little connections. I did remove the main jet assembly and have questions as to whether I put it back correctly. The main jet can slide up and down and I am not sure of the correct placement. i assume that it should fit down in the bowl as far as possible because that is where vibration would take it..

 

[kev_79]

Re: Force mid-range

I don't understand the part about drilling out the plugs. On the carbs? Please reiterate, and maybe we can walk through this. I am pretty sure I am fimiliar with this carb.

 

[rogerwa]

Re: Force mid-range

There is a circular hole on the top of the carb that has a domed shaped 'plug' pressed into it. Underneath the plug is access to the low speed fuel passages. This hole is used to gain access to clean them out. Replacement plugs are included in the rebuild kit.. <br /><br />I removed the plug and sprayed the heck out of them to enure the passages were clear and then tapped in the replacement plug..

 

[y-knot]

Re: Force mid-range

I'm not sure what carb you have, but did you adjust the float when you put it back? My 125 has a certain travel range. You are supposed to set it with a caliper and bend the tab as needed.<br /><br />Just a thought.

 

[chet34]

Re: Force mid-range

I have a 85 force 50 that had the same problem after checking everything I could think of I called the local Merc. dealer they told me to check the coils. I ended up having one that was droping out. replaced it and my problem is gone.. Have you checked your coils? Of course I am no where near as experienced as most of the people on here, but I hope this helps.<br /><br />Chet

 

[clanton]

Re: Force mid-range

You said in post that main jet moved up and down. The main jet, and main nozzle is screw in. The only that should move inside the float bowl, is the float and needle. If the main nozzle is not threaded, then sometimes it is held in with a spring.

 

[rogerwa]

Re: Force mid-range

Y-knot -- I put the float in with the same setting as before. I am not having problem on the top end or the bottom end. I would think that if I had float problems, I would either be leaking fuel out the front of the carb or I wouldn't have enough for WOT.<br /><br />Chet - were you dropping only at the mid-range?? My symptoms seems to be more miss-firing than dropping out. The motor jerks roughly at the problem range.. How would I diagnose the coil other than replacement??<br /><br />Clanton -- In the bowl, where the casting for the carb reaches down into the bowl, there are two pieces of brass inserted into this piece of the carb. One is a long skinny tube which goes all the way into the top of the carb. The other is a wider tube that slips over the skinny one inside this part of the carb. They are held in the carb housing by a brass nut with a hole in it that taps in from the side. The wider tube, which I was referring to as the main jet (wrong term??), is wider at the base with a step in the middle. The top of this tube ends in the throat of the carb. I can slide this tube up and down on the skinny tube until the step in the larger tube butts up against the carb body. The float bowl screw, goes into the bottom of this carb housing piece which also holds the two other pieces.<br /><br />I realize this may take some visualization. . but do I have it put together correctly?