While mothering in heavy seas (6to8') my rpm's would fluxulate from 2800 down to 2000. This went on for an hour then all was Ok. Any ideas what would cause this?.
Engine RPM's fluxulating
- Thread starter thaeni
- Start date
Your fuel filter(s) are probably clogged that happened to me also. The heavy seas stir up the gunk and the next thing you know no good rpm.
Keith
Keith
Keith is on to the correct issue. I have had several experiences with it. Installed a vacuum gauge on the motor side of the Primary fuel filter. When vacuum gauge reading is high filter is clogged. when reading is very high motor will stop from fuel starvation. Resolution... Stop motor before vacuum reading gets very high. Change fuel filter. Restart engine. If motor stops, then change fuel filter, bleed engine. attempt restart. Bleed engine... attempt restart... repeat as needed.
When motor restarts give it a couple of minutes to be sure fuel is flowing. Continue on your way.
When back to port you have several options... Fuel Polishing. Tank Cleaning and fuel polishing. Fuel additive and fuel polishing... or use up the fuel and have filters ready to change out should you experience the need.
When motor restarts give it a couple of minutes to be sure fuel is flowing. Continue on your way.
When back to port you have several options... Fuel Polishing. Tank Cleaning and fuel polishing. Fuel additive and fuel polishing... or use up the fuel and have filters ready to change out should you experience the need.
After following the good advice of Keith and jssailem you are still experiencing the problem, check to see if your throttle cable is slipping. Mine won't hold at certain rpms (those that cause harmonic vibration) unless I keep my hand on the handle. Someone else told me they use a small bungee to keep the revs steady.
GT. Boats and throttle linkage is not universal, but most of the time the design is to use some form of clamp to put friction in the throttle housing. Either on the cable or to the throttle handle. This is a wear point that requires eventual maintenance and adjustment. Or a good bungee.
I didn't interpret the OP's description as fluctuating "between" 2800 & 2000, but rather I picked up on the "down from" part. If going back and forth is the the case, then indeed it would not be a throttle cable problem.
I've never mothered in heavy seas nor have I fluxulated so I am no help at all.
Oh Mark. Clearly you are leading a sheltered life. Until you've been "mothered" in heavy seas you have not lived. I hope you get a chance in the near to you future. You will become reborn, be considered better looking and likely win the Irish Lottery.
Young intellectual "Do you like Kipling"
Young lady "I don't know you naughty boy, I've never kippled"
Young lady "I don't know you naughty boy, I've never kippled"
Thanks for reminding me about that little clamp. Took a look, and sure enough it was loose and just dangling there. Tightened her up an now I can hold at 3k all day, or at least until the fuel is gone!
Definitely a fuel issue. Start w filters, then pull fuel tank pickup and remove the little pre-screen.
If changing filters doesn't fix it, pull the dip tube out of the tank and see if there's a screen on the end of it. If so, cut it off, you don't need or want it. All filtering should be in the real filters, not in the tank where you can't get to it.
You're going to need a good strategery to properly deal with your fluxulation.