A little help with 787 carbs

[challenger1488]

I recently replaced my carbs on my 98 challenger 1800 when i went to put them on i had to switch the plate on the end. The one that was on the new carbs was for a single engine sportster. From what i can tell by comparing pics in manuel to what i had. It had a block with a gasket on one side and a plastic like cover sealing the other side with a plate on the end of all that. It also had a extra fuel nipple labeled pulse. I removed all that and put just the plate form my old carb on. It runs now but has some hesitation and wants to bog down around 1/2 to 3/4 throttle. it will come out of it and reach 7000. Just slower then my other motor All adjustments of HSA and LSA are the stock 1.5 and 0 Do i possibly have a jet issue here since this carb was set up for teh single engine boat. Carb was supposed to be set up all stock.

thanks for your help

 

[seadoobutch787]

On your 787 the front carb MAG will have the fuel pump bolted to it. The rear carb PTO will have a block off plate in place of the fuel pump with an arrow pointing into the carb and out of the carb. Inlet/return. The single engine carb that you had might have been the rear carb that doesn't require the fuel pump. Hope that helps you.

Usually the high side speed adjuster is lightly seated. The low speed adjuster should be around 1/1/2 turns out from close +or- 1/4 turn.

The low speed adjuster is mainly for your idle and bottom end. If it hesitates than i would richen it up a bit, if it bogs then you need to lean it out a bit, turn in the screw.

You will have to do a plug chop to gauge the condition of your engine. You want your spark plugs to have a cocca brown color on the porcelin.

 

[challenger1488]

im not 100% sure but i think the fuel pump is mounted separate to the motor there is a box with 3 lines going to it one to the carbs one to crankcase (pulse line?) and one to tank.
I assume the piece i took off was the fuel pump but the manuel does not show that hooked up to the challenger 1800 carb only sportster and i think single engine challengers

 

[seadoobutch787]

In that case maybe the challenger 1800 need a high output fuel pump.

On my limited mod 800xp i run a mikuni high output remote fuel pump that feeds both of my carbs. I have the block off plate on both the front and rear carb.

The remote fuel pump will have a pulse line barb which hooks to the pulse fitting on the engine and 2 outlets that go to each carb and a main fuel inlet barb. You might have 2 single high output fuel pumps or just one.