1990 Force 150

jefnmic

Cadet
Joined
May 11, 2003
Messages
10
Looking for any advice of a couple of questions! A little history, 3 carbs rebuilt, tuned up, fuel tank cleaned. Engine quits out at idle and at slow troll. Added an inline fuel filter...which came from Fram auto section of Walmart. Does the inline filter matter? What can be done to keep motor from shutting off? Idled fine and would slow troll fine before fuel filter was added and carbs rebuilt. <br />Have Power tilt and trim..raise motor and after short amount of time it slowly falls back down. What should I look at to fix this problem? <br />Advance thanks to those who offer help!!<br /><br />Had boat at mechanics for 2 months, he could not fix original problem....which ended up being a dirty fuel tank. Really missed boat this summer!
 

roscoe

Supreme Mariner
Joined
Oct 30, 2002
Messages
21,665
Re: 1990 Force 150

How long does it run before it dies on you?<br />Try pumping the primer bulb a couple times, about a minute before you think it will die, see if this will keep it running.<br /><br />If it does, you have a weak fuel pump diaphram, that needs replacing. $8-15.<br /><br />The inline filter shouldn't make a difference, unless it is a real real tiny one.<br /><br />How does engine run at WOT? <br />It woouldn't hurt to do a compression check.<br />______________________________________<br />As far as the tilt and trim, there are a few posts here about how to replace the check valve o-rings and seals in the pump body.<br /><br />But first you have to determine if it is the cylinder(s) or the pump that is faulty. You are going to have to use the search fuction for this info, or get a manual, as I have never done this.
 

U68423

Petty Officer 3rd Class
Joined
Jun 29, 2003
Messages
77
Re: 1990 Force 150

I almost made the same mistake, read the filter lable, I bought a real nice glass see through was just about to put it on and noticed that it said not for marine use ! in small letters. Something about fuel pump psi, hope this helps.
 

jefnmic

Cadet
Joined
May 11, 2003
Messages
10
Re: 1990 Force 150

Roscoe,<br />According to my invoice from the mechanic he charged me for two fuel pump kits and I have the old parts which look like a gasket and diaphram the kit is says Sierra 18-7806. The compression listed on the invoice states #1-136, #2-134, #3-140, #4-135, #5-140 psi. He rebuilt the 3 carbs, and spark plugs were changed. I filled the boat with High Test BP gas and used Valvoline oil. Ran the boat today and tried to pay attention to the idle..it's a little rough....feel some vibration throughout the boat...when wide open hesitates at first then will get up on plain. Boat shut off once while at idle..noticed it wanting to and pumped on the ball and watched the gas go into this fuel filter...then engine died. I kept watching this transparent fuel filter and it does not stay full of gas...if you pump on the ball gas does go in but a little bit later you only see a trickle of gas going in. I'll await for any further comments. THANKS!!
 

lonewolf5347

Chief Petty Officer
Joined
Jun 11, 2001
Messages
529
Re: 1990 Force 150

jefnmic the next step I would do is to change the complete fuel lines and primer bulb,
 

roscoe

Supreme Mariner
Joined
Oct 30, 2002
Messages
21,665
Re: 1990 Force 150

Your 5 cylinder engine does have 2 fuel pumps. And everything else looks in order. <br /><br />All I can think of right now, is that you have a small airleak in the fuel hose, between the bulb and the fuel pump. It is allowing the fuel pump to suck air. It may be at the connections for the inline filter, or on any of the other gas line connections.<br /><br />Pull off the cowl and pump up the bulb till firm, then watch the fuel lines for any sign of a leak.<br /><br />If you can't find the leak, replace gas lines, from tank to fuel pumps. Leave out the inline filter this time. You can always put it back in after you have fixed the problem.
 

sony2001

Chief Petty Officer
Joined
Mar 17, 2001
Messages
607
Re: 1990 Force 150

Your carbs are too rich. Unscrew the idle speed bolt at the bottom of the vertical shaft so engine is running on idle speed screws only. In rotation turn each screw 1/4 turn till rpm drops or idle is rougher. That screw then goes back a 1/4 turn. Carry on with other carbs and do the same. When all three are the leanest + 1/4 turn, Then screw in the idle speed bolt to the desired rpm. :cool:
 
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