1974 Mercury 850 Thunderbolt not firing

AlexVojn

Recruit
Joined
Apr 10, 2016
Messages
1
Hello and thanks for trying to help me out in advanced.

Whenever I turn the key, the engine has no problem turning over, but it won't fire. We've redone the wiring and we've put in new spark plugs. It used to start up, but it was hard to and would take a few minutes. The fuel is about 3 months old. I was thinking about checking the fuel pump next but it looks like it's really hard to get out and I would definitely avoid it if I can. Anyone have any other ideas?
 
Last edited:

merc850

Commander
Joined
Jul 7, 2010
Messages
2,055
Are you lifting the cold start lever (little one on STBD side of box) to vertical and pushing and holding down the choke button?
The instructions are on a plate between the clamps screws.
If so check that the choke shutters are closing all the way!
I have a 1975 850 and the fuel pump is in the middle of the block.
 
Last edited:
Top