1990 90hp stall Gremlin

kingfish62

Seaman Apprentice
Joined
Jun 6, 2007
Messages
42
My 1990 merch 90 horse has an issue that is baffling to say the least. Hope some of you have some ideas! On occassion the boat will stall completely during high speed turns or crossing a wake at high speed. When this event occurs the engine fails to restart due to a lack of fuel in the line. The bulb is empty and requires pumping to bring fuel pressure back to the system. The cabs are clean and seem to function properly. The fuel pump seems to be functioning properly as it will pull fuel back to the system if the engine is started using starter fluid vice pumping the bulb. The fuel/water seperator can is new. Any help in issolating this Gremlin would greatly be appreciated !!
 

kingfish62

Seaman Apprentice
Joined
Jun 6, 2007
Messages
42
Re: 1990 90hp stall Gremlin

10 views and no advice?? I pulled the top cap (inlet/outlet) of the fuel&water seperator system yesterday evening to see if it might be fouled. I found some small debris so I took it up to the garage and blew it out with LP Air. By the time I got it reinstalled it was dark and no boats on the water so I stayed at the dock. (dark =low to no boat traffic so limits tow possibilities if needed) I'm keeping my fingers crossed that the debris was the problem. I am still open to any ideas that all of you here at iboats may be able to hare. Thanks in advance, Mark CPO USN RET Hail Davey Jones!!!
 

mwhitten

Seaman Apprentice
Joined
Sep 29, 2006
Messages
34
Re: 1990 90hp stall Gremlin

If the fuel separator is new and this problem did not happen prior to it I would think there is a problem with my separator. Try connecting the fuel line directely to the tank, bypassing the separator. If the boat runs fine you will know where the problem is. If it continues to stall something may be in the tank plugging the fuel line during hard turns. This would require cleaning the fuel tank and replacing the fuel line.
 

kingfish62

Seaman Apprentice
Joined
Jun 6, 2007
Messages
42
Re: 1990 90hp stall Gremlin

Thanks for the reply, I should have stated earlier that the tank and lines are fairly new. Last year. 35 gal below deck alum. tank. Debris I found may have been construction related and thank god for screens and filters to catch it before it hits the engine. The new seperator filter was an attempt to isolate the problem as the stall was occuring prior to the change out.
 

mwhitten

Seaman Apprentice
Joined
Sep 29, 2006
Messages
34
Re: 1990 90hp stall Gremlin

Some of the time the fuel pump is not strong enough to pull through a large filter
 

kingfish62

Seaman Apprentice
Joined
Jun 6, 2007
Messages
42
Re: 1990 90hp stall Gremlin

As I said earlier if I spray fluid in the carb to start the pump will pull fuel from the tank to the engine. Last night I pulled the fuel line and found that it would not pump up to a tight bulb when disconnected from the engine. I believe I may have an air leak between the seperator and the engine clip. I'm goin to replace it today and chech below deck connections as well.
 

CharlieB

Vice Admiral
Joined
Apr 10, 2007
Messages
5,617
Re: 1990 90hp stall Gremlin

chitcan the quick connect fuel fittings, too many o-ring failures allowing air to enter the system and intermittant problems such as yours.
 
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