Inancarrow
Cadet
- Joined
- Jan 15, 2002
- Messages
- 7
Hi Guys,
keen to get some advise. I have a Yamaha F250A around 2009, very low hours.
It intermittently stalls out at idle.. it always restarts, but below around 1200 rpm is not running quite right. All the rest of the rev range is absolutely fine, but when you pull the throttle back particular when you come into a dock and shift to neutral the revs seems to come up then drop off and the motor stalls.. often when you restart it, it will surge/hunt and either stall out again or just settle down and be ok.. I find if you leave the engine out of gear and run with a fast idle for a couple of minutes it seems to stabilise the problem..
So I have good batteries, and cables, good compression, on all cylinders. Tank is clean and all primary filters changed. VST has been completely stripped with new 'F' filter and both high and low pressure pumps are functioning within spec. I have good/correct fuel pressure at the rail, through the complete rev range including when the engine does its cutting out thing. I have cleaned and tested the injectors on our ultrasonic test bench.. YDS show no faults at all.. and all data from what i can see seems to be in range.. So I'm ruling out fuel..?? It has no ISC on this model.. Any help at all gratefully received!!!?
The only thing I have seen slightly untoward is very occasionally the multi display on the round Yamaha gauge (tach) goes crazy, all functions seem to illuminate and the buzzer comes on.. it not related to what the engine is actually doing i just feel it maybe a back feed or an earth issue on the network.
Thanks in advance!
Ian.
keen to get some advise. I have a Yamaha F250A around 2009, very low hours.
It intermittently stalls out at idle.. it always restarts, but below around 1200 rpm is not running quite right. All the rest of the rev range is absolutely fine, but when you pull the throttle back particular when you come into a dock and shift to neutral the revs seems to come up then drop off and the motor stalls.. often when you restart it, it will surge/hunt and either stall out again or just settle down and be ok.. I find if you leave the engine out of gear and run with a fast idle for a couple of minutes it seems to stabilise the problem..
So I have good batteries, and cables, good compression, on all cylinders. Tank is clean and all primary filters changed. VST has been completely stripped with new 'F' filter and both high and low pressure pumps are functioning within spec. I have good/correct fuel pressure at the rail, through the complete rev range including when the engine does its cutting out thing. I have cleaned and tested the injectors on our ultrasonic test bench.. YDS show no faults at all.. and all data from what i can see seems to be in range.. So I'm ruling out fuel..?? It has no ISC on this model.. Any help at all gratefully received!!!?
The only thing I have seen slightly untoward is very occasionally the multi display on the round Yamaha gauge (tach) goes crazy, all functions seem to illuminate and the buzzer comes on.. it not related to what the engine is actually doing i just feel it maybe a back feed or an earth issue on the network.
Thanks in advance!
Ian.