Took the boat out to test a set of props from BBlades.gas gauge said 1/4 tank.decided to go to marina to get gas and when i was getting on plane the engine that uses more fuel for some reason started to make a craking noise and wanted to shut down.i was on plane twice when this happened.idled to gas dock put in 15 gal per tank and gauge came upto over 1/2 tank and got on plane again and it did the samething.hummm.looked back at the blower and there is a black thingamijig.it has a vaccum line on it and a rod that goes into it with a lever like it adjust when running.I'll go take a pic of it and post it now.

pics.Could it also have got something in the fuel filter from the fuel level being low.

Ck and see if anything came loose ?.Is something choking the motor down or just a noise?

I check to see but didn't find anything but a 1" hex head screw in the bilge.motor idles fine.Strip thats the black thing i was talking about.

I believe its a bypass for when you let out of it???so the boost doesn't spike

Take a pick of the bolt? It might of fell on the installation?

explain better whats it doing??

The bolt is just a s.s.hex head bolt like about dozen more on the blower.i went and looked again at both blowers to see if anything was missing from one and not another.couldn't find anything missing.i went back out to see if it did it again and it did. what it's doing is when i get to 3000 rpms it makes a clicking/popping noise and wants to kill the motor but dosn't.that lever/rod at idle doesn't move except when its in gear but other engine doesn't do anything.i have a small video of it moving in gear at idle.let me see if it will load.

Couldn't get the video to load.Another thing i noticed was that the starboard side motor is running very rich with soot on the transom but the motor thats giving me problems has no soot at all on that side.Does this mean it might be running lean?Hope this isn't a internal problem.

I would send out a call or post to Dustin at Whipple. He is the most knowledgeable on his blowers and I am sure he can help you find the culprit, hopefully before any damage is done.

RaY @ Raylar

I would give tyler crockett a call. He is the man when it comes to the whipples.

Does it make the noise in neutral when you rev it? Had a similiar problem on 500efi's after running one of them out of fuel. At about 2700 rpm a popping sound from one motor when under load. Could spin it to 5000 in neutral with no noise. Im no expert but fuel delivery could be the answer.