mercarb 1389-9350 advice needed

[DennisM]

Hello again and sorry for all the stupid questions. I am down to a great running boat execpt for a major bog at WOT from a dead stop. To the point it will die.

Have replaced fuel filter in carb, cap router, and plugs, and wires.

Low idle still as well. I am about to clean the carb completely but was wonder if anyone knows the stock settings for the idle and idle mix screws? I have no history of previous owners work on it, and like to put it back to stock when working on it to make sure i am not adjusting or missing something.

Its on a 86 merc 140 3.0..

Thanks

 

[fossill]

Re: mercarb 1389-9350 advice needed

accellerator pump circuit ok in the carb. Look down the bore and check to see if its squirting a good stream of fuel into the carb when you cycle the throttle rapidly full forward.

 

[TiredoleBoy]

Re: mercarb 1389-9350 advice needed

I believe it 1.25 turns out.

 

[DennisM]

Re: mercarb 1389-9350 advice needed

Ok one side was not squirting really at all, and the other was not a nice steady stream.

What is the accelerator pump and is it replaceable?

 

[TiredoleBoy]

Re: mercarb 1389-9350 advice needed

Ok one side was not squirting really at all, and the other was not a nice steady stream.

What is the accelerator pump and is it replaceable?

It is replaceable if you know how to take the top off and make the adjustments. If I am not mistaken you will need to disassemble the old pump springs and clip to install on the new one. But This could also indicated debris in the carb float bowl. If there is then I would take the entire thing apart soak it and rebuild it.

Oh and this is why the problem with acceleration.

 

[DennisM]

Re: mercarb 1389-9350 advice needed

Ok new problem.

No one local has the gasket kit and I can not afford the 60 bucks for it until late this weekend.

The old gasket between upper and lower section of the carb broke, otherwise was in great shape, it broke apart in two spots.

Could I use the cork roll gasket material to make a temporary gasket for it? I tried using #2 rtv form a gasket to hold the two breaks together but it will not line up and hold.

dennis

 

[DennisM]

Re: mercarb 1389-9350 advice needed - UPDATE

Re: mercarb 1389-9350 advice needed - UPDATE

Ok took entire carb off boat.

Got the gasket sealed nice and neat. Cleaned the carb about 75%
Did not take the needle and seat out, but cleaned everything else.

Took her back out this morning, still only getting about 20 Mph at 3500 rpm at wot. Still bogs from a dead or near dead stop.

Is the carb rebuild in order here or could there be something else I need to check first? Card kit is 60.00 bucks for this carb and would hate to spend that right now if that isnt it..

it is driving me nuts, and the wife is not happy either, 600 bucks so far and still cant take the fam out...

 

[Eric 3.7LX Alpha 1]

Re: mercarb 1389-9350 advice needed - UPDATE

Re: mercarb 1389-9350 advice needed - UPDATE

Ok took entire carb off boat.

Got the gasket sealed nice and neat. Cleaned the carb about 75%
Did not take the needle and seat out, but cleaned everything else.

Took her back out this morning, still only getting about 20 Mph at 3500 rpm at wot. Still bogs from a dead or near dead stop.

Is the carb rebuild in order here or could there be something else I need to check first? Card kit is 60.00 bucks for this carb and would hate to spend that right now if that isnt it..

it is driving me nuts, and the wife is not happy either, 600 bucks so far and still cant take the fam out...

Is this a new problem with the boat, meaning previously it has run at higher RPMS at WOT? or is this boat new to you?

Could be wrong drive ratio in outdrive if this has always been like this. Who knows what prev. own did?
Just throwing it out there...

 

[DennisM]

Re: mercarb 1389-9350 advice needed

PO bought the boat used from a local marine 4 years ago, used it as it came for two years.

Deloped a leak, (3.0 not winterized crack) then let it sit for two years.

I have repaired the crack, replaced, starter, steering cable/helm, trim pump and motor, cap rotor, and plugs. New impeller and gear lube.

Changed oil three times, got all the water out, no new water in engine.

I would have to think it will run higher and faster. It bogs really bad when I gun it from either a dead stop of a slow start, like I would if pulling a skier.

I can feather the throttle and it will increase speed and plan out, but tops out at 20 and 3500.

Also just to add, if I do not have the boat running, and I give it gas, i can not see any fuel going into the carb. It starts right up after one pump from a dead cold engine and once running it will fire right up after being turned off.

 

[fat fanny]

Re: mercarb 1389-9350 advice needed

D I sent you a PM your carb needs rebuilt! completely dissasemble clean and soak and re-assemble all the instructions are in most kits. In the PM I sent you a vendor where you can get a kit @ 1/2 the cost of what your saying. if the 2 jets on the venturi cluster aren't shooting 2 strong jets of fuel out when you gun it it is plugged up and needs rebuilt to run properly period!!!!!!! If the PM I sent you did go through send me a PM and I will redue it for you. TOO hot not to be in the water!!!!!!!!!!! good luck!!!!!!!!!!

 

[fat fanny]

Re: mercarb 1389-9350 advice needed

D I sent you a PM!!!!!!!!!!!!!!

 

[DennisM]

Re: mercarb 1389-9350 advice needed

Ok going to order the rebuild kit today. Most likely wont get it until end of next week.

In the mean time, I plan on tearing the whole carb down and soaking etc.. then seeing if that works.

Is the accel pump the little rod that as the sprint under it that the throttle linkage pushes into from the side of the carb?