225 johnson losing rpms at full speed

[fire tech]

225 johnson v6 vro<br />at full throtle runs about 5500 rpms then it will<br />cut back to 4500 rpms and sometimes it cuts back to 3500 rpms then it will go back to 5500 rpms <br />and so on.the motors not over heating and i've<br />run omc carb. cleaner thru it to try to fix this problem, need some help on this one guys

 

[hydrasports]

Re: 225 johnson losing rpms at full speed

Im sure the pros on here will help you through troubleshooting steps, I had the exact same peoblem with a 150 johnson and it was my powerpack good luck.

 

[rickdb1boat]

Re: 225 johnson losing rpms at full speed

fire tech,<br />Begin by making sure your fuel tank vent is clear. Does the bulb stay firm while running? Check the fuel filter, anti-syphon valve going to the tank and fuel line. Might try running off a 6 Gal. Tank to eliminate any problem their. If that checks out, then I would start to look at the electrics(Powerpack). When it dies down, have someone pump the bulb to see if it speeds up. If so, the fuel pump may be weak.