motor surges

[slouw]

Force 120hp (Chrysler)<br />1. motor surges between 3000 & 5000 rpm at full throttle<br />2. Cruising upto 4000 RPM seems to be normal<br /> Engin 40 Hours - never been worked on<br />Checked fuel filter - Normal<br />Checked spark plugs - Normal<br /><br />Any Ideas / references

 

[dkondelik]

Re: motor surges

Mornin Slouw,<br /><br />WOW! not a lot of info to werk with.<br />Does it cruise OK at lover revs? Idel OK?<br /><br />Maybe fuel system. Motors will race as fuel becomes scarse. Is the primer bulb colapsing? Tank Vented? Have you tried using a differebt Fuel Tank/Lines/bulb?<br />Carbs (jets)clean?<br /><br />???