BF60a efi overfueling at tickover

Hi folks,

I was repowering a pals boat with a bf60a and when we had it running on tickover then there seemed to be a lot of fuel getting into the water barrel it was in. I`m more used to dealing with carb outboards rather than efi setups and wondered if anyone had any ideas what could cause this?

There are no signs of any external fuel leaks but it used over a gallon of fuel just ticking over for a wee while so something isn`t right. The outboard was seen running before he purchased it and seemed to be fine and has since been layed on it`s side on a pallet waiting for me to get some free time to rig it for him.

Any help with this would be gratefully received.

Matt.

Very possibly, you have a stuck float in the vapor separator and the overflow is coming out the intake.

Tilt the motor up some and squeeze the fuel bulb...checking to see if there is any fuel coming out the intake or surrounding areas.

Sometimes a stuck float will also cause the oil level to get higher and the plugs to get fouled.

Looks like you have some snooping to do.

Mike

Cheers Mike

I`ll have a look the next time i`m up there. I know my pal took the vapour separator off to fit a new fuel pipe so it wouldn`t surprise me if this could well be the problem. There was also a smell of petrol in the engine oil so that would fit in as well.

Matt

I went up and stripped off the complete VST this afternoon so will get it opened up hopefully this weekend and have a look what the condition is like inside. I`ll take some pics and post them up so other people can see what it`s like inside in case they have a similar problem.

Matt

Ok, well i got a chance yesterday morning to get the vst stripped down for a quick check over and it looked pretty good. I took out the float needle to check it`s seating and operation and also gave the pump screen a check. Apart from that then it was a general clean and it`s back together and ready to refit.













Matt

Hi folks,

I thought i`d do a quick update on this problem as we finally got to the bottom of it. Having refitted the VST then we found that we still had this overfuelling problem.

Much scratching of heads was done and then we decided that we`d take off the common rail with the injectors still in attached and see what sort of spray they were giving. We put a drinking glass on each injector to catch any fuel and switched the ignition on to it`s run position. Injectors 1 and 2 didn`t do anything as expected but number 3 pumped out about half a glass before it shut off. (something not right) We then tried turning the engine over on the starter for 5 seconds and got a fine spray coming out of 1 and 2 as it should be but number 3 constantly pumped fuel and filled the glass. (definitely not right)

More head scratching and we started swapping the injectors around to see if the problem moved with the particular injector but it didn`t and stayed on number 3 wiring connection position. We were then thinking that it must be the ECU that had gone haywire and would need to go to get checked out at a dealership when we noticed the routing of the wiring that feeds the injectors didn`t look quite right.

We started to reroute the wiring from where it was and found that it`d been getting rubbed by a cam belt pulley and had cut through one of the wires that feed number 3 injector. We quickly spliced the wire to check to see the effect and everything was working the same a number 1 and 2.

Everything refitted and the engine fired up without any problem minus the fuelling problem all running sweet. I`ve worked on hundreds of different engines both on bikes and outboards over the years and this shows how something as simple as a broken wire can cause different types of problems.

Matt

Nice trouble shooting! I did not mean for you to take the vapor separator apart....just check for overflow.

What you found makes sense....the ECM is sending pulsating grounds to operate the injectors. You just had a constant ground. I know you know that, but others reading this may not.

What did the spark plug look like compared to the others? Was is washed clean or was it fouled?

Also, was the wiring run like that from the factory or did it get moved for some reason? I don't have a 60 to check out. Just wondering if the same problem might show up on other 60's.

Enjoy your motor.

Mike

Cheers Mike.

Number 3 plug was washed clean as it couldn`t keep up with the amount of fuel getting pumped into the cylinder plus the engine oil smelt of petrol and when drained out then there was far more oil then there should`ve been.

The previous owner of the engine had fuelling problems on his fishing boat but as it ran twin 60`s. The problem came to light when the engine was fired up for the first time after fitting to my pals boat running in a barrel.

The routing was wrong due to it previously being worked on by someone i think rather than a factory problem. The wires were routed behind the timing belt cover rather than on the outside of it. It would be an easy enough thing to do to get the wires trapped on the wrong side of the belt cover so might be something to look out for.

Anyway, my pal is happy but he`s moving to the west coast of Scotland at the end of the month so i`ll not get to see how the repowered boat performs until he and his family are settled over there and the boat is on a mooring.

Matt