Hello. This is my first post on this forum.
I am a 28 yr old guy from Denmark, having trouble with my Yamaha 40 hp, 2 stroke, 3 cyl - 1987 40ELH
I simply cannot get the engine proper tuned.
Story made short, everything has been taken apart.
Replaced parts:
- Complete new powerhead gaskets
- Reeds (carbon 0,3mm 'are these thick enough compared to original steel??')
- Piston rings (all repair manual wear limits are within spec)
- Lightning coil (the old one red 0,7 ohm - so broken)
- Upper and lower crank bearing
- Sparkplugs
- Fuel lines
- Sparkplug caps
So the sad part of the story is that after assembling the engine back together, I am just back to where I started.
Engine impossible to tune up.
I have setup everything by the repair manual specifications.
All OHM readings are within spec.
Timing:
Idle: 4-6 ATDC
Carb pickup: 0-2 ATDC
Full Advance: 24-26 BTDC
Carbs:
Pilot screw: 1 3/8 - 1 7/8
Float drop setting in mm. 12-16 (This one I am wondering if I am doing correct - someone please describe this in detail - how can it vary 4 mm??)
Symptoms are: Rough idle, sneezing, stalls when increasing RPM, fuel running out #1 and #2 carb (not spitting - which indicates float problem, correct?), alot of smoke.
I have already tried the following:
Cleaned tank, replaced fuel, precise oil mixture, carburetors cleaned with several products (carbcleaner, ultrasound etc.) tried to follow the link&sync as best I can.
My main suspicion are with the carburetors! And here I have a few questions. Can you take the jets apart in the 6H4-14301-06-00 carburetor? Someone told me they are 'heated?' in? Dont know the english term for this. Also, how can you balance these carburetors, when there is no where to hook up a gauge?
And as mentioned above, how do you set a float drop to 12-16 mm ??? Does that mean just somewhere in between?
I really hope some of you can help me.
Sorry for the bad spelling.
Thomas
I am a 28 yr old guy from Denmark, having trouble with my Yamaha 40 hp, 2 stroke, 3 cyl - 1987 40ELH
I simply cannot get the engine proper tuned.
Story made short, everything has been taken apart.
Replaced parts:
- Complete new powerhead gaskets
- Reeds (carbon 0,3mm 'are these thick enough compared to original steel??')
- Piston rings (all repair manual wear limits are within spec)
- Lightning coil (the old one red 0,7 ohm - so broken)
- Upper and lower crank bearing
- Sparkplugs
- Fuel lines
- Sparkplug caps
So the sad part of the story is that after assembling the engine back together, I am just back to where I started.
Engine impossible to tune up.
I have setup everything by the repair manual specifications.
All OHM readings are within spec.
Timing:
Idle: 4-6 ATDC
Carb pickup: 0-2 ATDC
Full Advance: 24-26 BTDC
Carbs:
Pilot screw: 1 3/8 - 1 7/8
Float drop setting in mm. 12-16 (This one I am wondering if I am doing correct - someone please describe this in detail - how can it vary 4 mm??)
Symptoms are: Rough idle, sneezing, stalls when increasing RPM, fuel running out #1 and #2 carb (not spitting - which indicates float problem, correct?), alot of smoke.
I have already tried the following:
Cleaned tank, replaced fuel, precise oil mixture, carburetors cleaned with several products (carbcleaner, ultrasound etc.) tried to follow the link&sync as best I can.
My main suspicion are with the carburetors! And here I have a few questions. Can you take the jets apart in the 6H4-14301-06-00 carburetor? Someone told me they are 'heated?' in? Dont know the english term for this. Also, how can you balance these carburetors, when there is no where to hook up a gauge?
And as mentioned above, how do you set a float drop to 12-16 mm ??? Does that mean just somewhere in between?
I really hope some of you can help me.
Sorry for the bad spelling.
Thomas