88 Special Carbs

[MudkatBlues]

I have an 88 SPL and I’m not getting a full throttle response at all from the motor. It lags quite hard but will pick up from time to time (briefly). If you engage the electric choke she picks up. I’ve rebuilt the carbs but I’m guessing the top carb is not getting an adequate fuel supply. Steps to solve this issue?

 

[racerone]

The high speed jet ( orifice plug ) is in the bottom of the float bowl.----There are 4 of them in total on your motor----They are about 5/8" long.----They must be clean.---Also post compression numbers .---These motors have a history of broken piston rings.

 

[MudkatBlues]

121 and 120 on top 2 and 120/118 on bottom. I heard I need to check the butterfly valves and make sure they are evenly closed. My floats are not level with the carb bowls either. I did check for vacuum leaks and found none

 

[boobie]

Did you check the high speed jets like Racer said ??

 

[racerone]

Perhaps test run with cowling off.----Perhaps test run with another gas tank and hose.

 

[Faztbullet]

Make sure you use new gaskets when clean/rebuild carbs

 

[MudkatBlues]

Make sure you use new gaskets when clean/rebuild carbs

I’m going to pull the carbs tomorrow and do that. I cleaned all jets with a wire brush when I rebuilt them just a few days ago

 

[racerone]

The high speed jets ( orifice plugs ) are screwed into the FLOAT BOWL.---They are NOT in the main carburetor body.------Not sure how you would clean those with a wire brush.----Also check fuel pump diaphragm.

 

[MudkatBlues]

Perhaps test run with cowling off.----Perhaps test run with another gas tank and hose.

I tried a new tank and new lines and fittings. No change

 

[MudkatBlues]

The high speed jets ( orifice plugs ) are screwed into the FLOAT BOWL.---They are NOT in the main carburetor body.------Not sure how you would clean those with a wire brush.----Also check fuel pump diaphragm.

Well when you tear the carb completely apart then use a carburetor brush kit that fits in the jets it’s quite simple

 

[racerone]

Have you confirmed that the high speed orifice plug is clean , yes or no ?----Engaging the electric primer valve puts fuel directly into the intake manifold.----This fuel bypasses the metering circuits and jets.----This strongly suggest there is an issue with carburetion !!----Yet you say cleaning is " quite simple "----I hazard to say that you overlooked something.

 

[oldboat1]

I would disassemble and soak at least the carb tops (disassembly including four core plugs -- replacements included in kits -- and the top cover for the idle channels). You need something that will dissolve fuel varnish. Finish with carb spray in every opening. I would at least spray the four h.s. jets in the two float chambers.