1988 Mariner Magnum 2

[ltcricket@yahoo.com]

Ok I have done all I know to do so I am now coming to the experts. Bought 1985 ranger last summer with 1988 Mariner 150 on it. Didn’t get much time to run last year but did ok but was very hard to start. Like would turn and turn but not start and starter kept kicking out. So what I have done since then.

-Cleaned starter
-Changed bindex
-Changed starter
-put on 1000 cca battery
-replaced all the fuel lines including ones on motor
-replaced primer bulb
-replaced fuel filter
-checked choke (its good)
-replaced key switch
-cleaned carbs (they were very clean) none of the jets were clogged at all
-rebuilt fuel pump

issue now still semi hard to start on hose and harder to starter in water

-when I prime bulb it gets hard but fuel filter is only bout 2/3 full.
-When running there is almost no fuel in filter
wont run long before dying
-Was having to start at full throttle but when I backed off to put in gear would die
-after it starts runs and dies the primer bulb is soft again.

So there you go any help would be great. If I left off anything just give me a shout

 

[Dukedog]

first thing would be to track down an OEM manual (no to after market junk).. go through all steps with carbs, fuel delivery, 'lectrics, compression test... there are way to many things to cause what you describe to try to diagnose ona computer.. for me anyway.. one thing I "think" I see wrong is with "carbs were clean".. did you replace all tha gaskets, inside and out when ya took 'em apart or decide they were "good" as is?

 

[roscoe]

Check compression ?? and spark ??

 

[ltcricket@yahoo.com]

These carbs were clean when I opened them up. I did clean them all again to make sure and replaced all the gaskets.

I have checked the compression and all were at 125 psi or with in 1-2 pounds

spark is good but I wondered about timing.

 

[Dukedog]

that can be a real pain.. you really need tha manual for a good, clear explanation of tha "how to".. there is lot that can be "lost in translation" ona computer!...….. jmo.

 

[Chris1956]

If the starter kicks out, the motor is firing, at least once in a while. Your challenge is to get it to fire a lot more.

I would spray some mixed fuel into the carbs, and see if it will fire up. If she fires up and runs, I would suspect the choke plates are not closing, or the motor is not cranking fast enough.

If she doesn't fire, Duke has provided sound guidance. Some of those early V6 Mercs have NLA carb floats, so be careful with them.

 

[ltcricket@yahoo.com]

UPDATE!!! UPDATE!!!

I went back over everything today except carbs. Verified Fuel pump made was working. I pressure tested all the fuel lines in separate areas and all together. I did find the fuel bulb was loosing pressure so replaced it.

Its is starting and idling but when I rev up and idle back down it dies. It also dies after idling for awhile. Its seems to run out of fuel and die. If I pump primer it would stay running. Since I found no air leaks. Not sure where to look next.

 

[Dukedog]

UPDATE!!! UPDATE!
Its is starting and idling but when I rev up and idle back down it dies. It also dies after idling for awhile. Its seems to run out of fuel and die. If I pump primer it would stay running. Since I found no air leaks. Not sure where to look next.

this normally points to fuel pump problems and/or bulb even if new...…. runnin' outta fuel... pump tha bulb and it fills tha carbs like tha pump is supposed ta do.... does tha bulb stay firm?

 

[racerone]

The fuel pump is driven by a positive pressure pulses and slight negative pulses from the crankcase.----Perhaps there are issues there ?