Mercury Thunderbolt 850 Blueband

[smudgermpk49]

Hi all, I have a Mercury Thunderbolt 850 Blueband and just recently when I put the throttle up the engine gets starved of fuel and stops. If however you squeeze the fuel ball then the engine runs fine. I have changed the furl line and tank but still the same problem. I added a fuel filter but again still same problem. The wierd thing is that at low speeds it works fine. I am also a novice when it comes to motors. Can anyone shed any light on this and does anyone know where i can get a service manual for this model HELP please.

 

[merc850]

Re: Mercury Thunderbolt 850 Blueband

If you have this type of carb take the fuel line off and dispose of the filter.

 

[smudgermpk49]

Re: Mercury Thunderbolt 850 Blueband

Hi merc850 thanks for the quick response ill check tommorow the fuel filter that
I added was before the the fuel ball . so ill take of the cowling and have a look .

 

[Faztbullet]

Re: Mercury Thunderbolt 850 Blueband

If it started acting up after you added filter you could be sucking air from a bad connection or the filter is to restrictive. Also the added restriction would make the fuel pump work harder and if it was on the verge of being weak it nows shows up. I would replace the diaphragm in fuel pump if it hasn't been serviced in a couple of years...