1991 Pro V200 power loss

[dilb1229]

I posted under this same topic 2 months ago (July 17) and thought we had it licked, but intermittent problem persists. Back then, it was thought to be a fuel flow problem of some kind. I took the carbs off and removed the bowls. Spotless. Replaced the water-separating fuel filter. Blew out the fuel line from filter back to the tank and from filter to motor. Blew out the tank vent tube. Changed the plugs. Changed out the primer bulb.
Boat still ran at 80%. Fair power, enough to pull skiers, but those of you with a similar motor know what it can really do. Top end at 5200 rpm vs 6000.
Then, next time out, it ran great. Full power and top end. Next several trips, it continued to run great. Then, ran rough for the first 2 minutes, then great. Next time, rough for about 30 seconds, then great. (Had added a can of SeaFoam for that one.) Last time, back to 80% the whole time. Checked plugs and they look OK.
Any more (or same) suggestions?
Thanks again. Steve

[Ken]

Steve,
Next time the motor peaks at 5200, have someone pump the primer bulb several times. If the rpm shoots up to 6000, then you have bad fuel pump(s).
Good luck [img]smile.gif[/img] ,
Ken K

[jb123]

you took apart the carbs and LOOKED at them?? you should have cleaned them, altho they appear to be clean they are probably clogged with an intermittent problem like that. i have an 89 pro-v and the only other issue i EVER had with it besides clogged carbs were the coil leads leaking spark, which you can see by running at night.the older carbed motors are very prone to clogging and the pro`s have that much more demand.

[dilb1229]

You guys are fast! I'll try the primer bulb again next time out, possibly this weekend depending on the weather.
The fuel pumps were a problem several (4-5, maybe 6) years ago and they were replaced (original 1991, both were bad). About 2 years ago, had a similar problem and changed them out again, but it wasn't the fuel pumps at that time, it was a stuck butterfly valve. I kept the fuel pumps I took out and swapped them back with no change. No tears in the diaphrams. Pretty sure all four are OK, but won't rule them out.
I guess I'm not understanding how the performance goes back and forth between running perfect several times out and then poorly. Keep in mind that the poorly is exactly the same each time, will get to 5200 rpm. Seems like there should be some variation if it's an intermittant clog, or the fuel pumps would either work or not.
Thanks again. Hope to try out your suggestions this weekend. - Steve

[slim]

have you ever heard of backflushing the seats in the carbs? disassemble the carbs all the way. if you have access to a parts washer, hook it up to the pressure washer and watch the spray patterns out of the seats. if one looks like its weak compared to the other or it isnt a constant even flow. you need to back flush this seat. to do this, locate a rubber air hose nozzle and put it on a fuel hose hooked to a 6 gallon tank with a primer bulb. lay carb flat on the intake side in a pan with a white paper towel in it under the carb. this is so you will see a peice of trash if or when it comes out. push the rubber tip into the suspected seat, block off the other with your finger and squeeze the primer bulb a few times. push at least a 8th cup of fuel threw it to dislodge any trash. usually this trash is a piece or the fuel hose cut by the barb on the carb. this was a pretty common problem down here on the coast and this is the only way to remove it being able to see it. good luck.