yamaha 85 leaky carb

tobylifeboatcrew · 29 August 2014, 09:59

any advice and help of any kind most welcome please!!

Nos4r2 · 29 August 2014, 10:53

Where's it leaking from?

tobylifeboatcrew · 29 August 2014, 13:17

hi thanks for getting back, i am not too sure yet i have to investigate further, i bought the boat yesterday and towed it back from Belgium, during transit the fuel pipe was connected to the engine, and it seems to have decided to overflow from somewhere.

RIB-Teccie · 29 August 2014, 16:38

Probably a bit of dirt in the float needle valve holding it open. The carb will flood and leak. Unless you have a missing o ring in the fuel filter or a hose has disconnected it would be hard to see it being anything else.

Peter_C · 29 August 2014, 17:46

Connect a fuel tank and pump the fuel bulb. Watch for leaks! If not leaks tow down road shortly. Watch for leaks! (Note make sure motor is in the position it was towed in.) Needle seats failing are fairly common. If one failed I would recommend doing full carb rebuilds.

tobylifeboatcrew · 29 August 2014, 18:14

fingers crossed its a nice easy one! many thanks, i had wondered if the long car journey from Belgium and given things a good jiggling? its one of the jobs to get to the bottom of! many thanks guys
also engine was in full tilt up position during transit

paddlers · 29 August 2014, 19:07

I had an issue with a Mariner 115 that turned out to need new float needles! Fuel gushed out into the air filter and was really bad with the engine tilted up running or not. Easy fix & worth a look.

tobylifeboatcrew · 29 August 2014, 19:12

nice one, i am going to be brave and have a poke at it, probably in the morning!
thanks

doggypaddle · 29 August 2014, 20:41

My 80 will dribble fuel out of the carbs if its tilted fully up for towing.
I wonder if you left your fuel tank vent shut and the fuel hose connected?
Trimmed up the carbs may dribble out of the float chambers through the main jet because of the extreme angle, and the fuel was being replenished by the pressure in the tank caused by warmth and slopping fuel?
I always run mine out of fuel by disconnecting the hose and leave it disconnected before towing.

tobylifeboatcrew · 29 August 2014, 22:14

thanks doggypaddle, everything you wrote is spot on! thats exactly what happened with the towing, i will have to run some tests to verify but you could be right on the money!! many thanks