Advice for an idiot

[jonmitch]

This is probably a blooming obvious problem but...

I took the RIB out yesterday after a few weeks off and couldnt get the engine (Yamaha F100) to rev, restricting me to 7 knots!! Fuel fine.

First off I thought it was a throttle control problem but with the engine cover off, the controls all looked to be moving fluidly.

The engine revs to 2500rpm in neutral and seems to turn over OK, and starts immediately.

Any ideas???

Ta, in advance!!

[jambo]

Hi heard of this before in a mates Evinrude. Depends how old the engine is it maybe that because it has been a while and cold it may have taken a while to start and the chip has shut it down the system. Talk to your dealer it may need re programming.
Cheers

[Poly]

Originally Posted by jonmitch

...Fuel fine.

Not sure what you meant by that... but it does sound like a fuel problem.
(1) tank breather closed/blocked (iced up?)
(2) kink/restriction in a fuel line
(3) blocked fuel filter
(4) duff primer bulb/non return valves
(5) maybe water in fuel
(6) dodgy fuel pump

Does it pick up at all if you pump the primer bulb?

[Sammo]

I've seen similar before also,

The computer in the engine think's there is a fault, so restrict's your speed etc (take me home mode)

Unless there is a fault that you can find, the only way really is a dealer to plug their laptop in and find the fault and reset it!

[Solent-Salted]

Originally Posted by Sammo

I've seen similar before also,

The computer in the engine think's there is a fault, so restrict's your speed etc (take me home mode)

Unless there is a fault that you can find, the only way really is a dealer to plug their laptop in and find the fault and reset it!

Aye, agree with this, if it's a new engine, sounds like it's dropping into guardian mode.

Could just be a faulty sender, but you wont know until you get some one to plug in a lap top and potentially charge you for the pleasure.

[geoff]

I had the same thing happen to my F100 Yamaha.
The engine had gone into safe home mode because the oil pressure guage was faulty. You need to take it to a dealer who will track down your particular problem and get you going again.

[jonmitch]

Thanks guys. This sounds very sensible.

Will get the dealer to fleece me.

Happy Christmas!!

Jon

[jonmitch]

Does it pick up at all if you pump the primer bulb? [/QUOTE]

The fule is fairly new, the pump seems fine and no apparent kinks. It doesnt pick up if I prime the bulb.

Thanks for the advice.

Jon

[9D280]

Jon,

Another trick is to go round the entire wiring harness unplugging, WD40-ing & reconnecting all the connectors. Assuming an engine management "limp home mode" due to a detected duff sensor, a bad connection is infinitely more likely than an actual failed sensor. I can think of dozens of automotive examples of exactly that scenario......

Problem is the box of electronics isn't that clever and so you'll probably end up paying through the nose for a replacement sensor that wasn't broken in the first place, but that will seem cured because the bad connection that caused the computer to think the sensor was dud was re-established when it was changed.

A simple exampe with my old engine - neither key or deadman would turn it off. One bullet connector in the remotes was slightly corroded - it was the one that shorted ignition to earth - and because it was the one that connected the end of the loom to the rest of the remotes wiring.......

If that don't cure it, the dealer is probably a good shout!