columhorgan
Recruit
- Joined
- Jun 7, 2007
- Messages
- 2
Hi,
I've a fuel problem and want advice on the next steps. It's a 2006 tohatsu 50MD2 3-cylinder, Carburetor model. (Same as Nissan I think)
Starts fine, idles fine. When I run at 3/4 to full throttle for a minute or so, the power drops. When I pump the bulb it goes back to normal and can stay at WOT if I keep pumping the bulb. Bulb is quite firm I don't have a seperate fuel seperator filter fitted (should I?)
I suspect that it's either a Carb problem or something from the tank up to the carbs. Tried the following but still have the problem:
- Change tank: I have the same problem on two seperate tanks (I alternate them).
- The vent cap is open and had the same problem when removing the complete filler cap.
- Cleaned the under-the-hood fuel bulb filter. Had an amount of crud in it.
- Changed to a different fuel supplier
Based on some good similar postings here, I'm assuming the order is something like the following - Any opinions appreciated.
1. Check for leaks along the internal fuel line
2. Check for leaks along the external fuel line to the tank including connections.
3. Replace fuel line, bulb and connections
4. Replace tank
5. Physical check of fuel pump diaphragm etc
6. Strip and re-furbish carbs (done about 30 hours ago - allegedly). One point to note is that although the carbs were drained for the winter, when I started the engine for the first time this season, the bottom throttle stuck open - obviously some fuel/oil gummed it up. I freed the stiff butterfly with spray oil without stripping the carb.
Any other diagnostic tricks?
Thanks in advance.
Colum
I've a fuel problem and want advice on the next steps. It's a 2006 tohatsu 50MD2 3-cylinder, Carburetor model. (Same as Nissan I think)
Starts fine, idles fine. When I run at 3/4 to full throttle for a minute or so, the power drops. When I pump the bulb it goes back to normal and can stay at WOT if I keep pumping the bulb. Bulb is quite firm I don't have a seperate fuel seperator filter fitted (should I?)
I suspect that it's either a Carb problem or something from the tank up to the carbs. Tried the following but still have the problem:
- Change tank: I have the same problem on two seperate tanks (I alternate them).
- The vent cap is open and had the same problem when removing the complete filler cap.
- Cleaned the under-the-hood fuel bulb filter. Had an amount of crud in it.
- Changed to a different fuel supplier
Based on some good similar postings here, I'm assuming the order is something like the following - Any opinions appreciated.
1. Check for leaks along the internal fuel line
2. Check for leaks along the external fuel line to the tank including connections.
3. Replace fuel line, bulb and connections
4. Replace tank
5. Physical check of fuel pump diaphragm etc
6. Strip and re-furbish carbs (done about 30 hours ago - allegedly). One point to note is that although the carbs were drained for the winter, when I started the engine for the first time this season, the bottom throttle stuck open - obviously some fuel/oil gummed it up. I freed the stiff butterfly with spray oil without stripping the carb.
Any other diagnostic tricks?
Thanks in advance.
Colum
