outboard won't run right

bluemonster1

bluemonster1

LIFE MEMBER ONLY ONCE!!!
Joined
Dec 30, 2005
Messages
12,690
Age
68
Location
Howden ,Manitoba,Canada
I have this 7.5 Merc and can't seem to get it to run right.It is hard to start,won't idle down without stalling.When I run it in a barrel at moderate speed..the motor runs high and then runs low by itself.Seems like a fuel issue,but went thru all that.Carbs cleaned several times with no issues..float adjustment done as per manual.Fuel pump was rebuilt,new gas line and checked gas tank for any defects on the intake and such and all is good.If I remove gas line from motor,,the motor will still run for about 40 seconds and dies ,So the carbs have gas.I was thinking it could be a stator issue.What are the symptoms of a bad stator...hard to start and bad idle and fluctuating speeds.......dam stator is around $300 to $400 to buy depending where I buy..this thing is really frustrating..damn idiot who sold it to me said it runs well..another liar and a cheat seller...any one with outboard engine experience..please help.I also did the link and sync as per manual...also put new plugs in as well.. #$%&* :o|

stumped here!!!!!!
 

is the primer ball allowing fuel to flow? have seen this cause a similar issue.

is the vent on the tank clean and working? you can try running it with the tank cap off. had to do this with one tank for my uncles 30hp yamaha as the vent did not let enough air into the tank at upper rpm.
 
bought a brand new fuel line and bulb is full .The vent is open on tank cap and have even loosened cap off..no difference at all.Like I said earlier..carb has gas because after I disconnect fuel line...motor runs another 40 seconds on the fuel in carb...
 
that was great help blue..I have paddles..,but haven't tried motor in lake yet until I can solve this,otherwise will look for another motor exact same..strip parts to the other and see if anything can be solved,,then sell 1 motor.
 
Sounds like air leak to me. I have seen carbs leak air in the body themselves or at gaskets. Use a spray to see if you can affect the rpms by spraying along the intake tract. Obviously allowing it to be drawn in the normal intake will affect rpms. Also richen and then lean the mixture (choke or whatever it has) to see which way it is running now.

Don't know anything about that particular motor, but I would start by testing the stator out electrically. That said sometimes they test fine on the bench, but work improperly on the motor.
 
I actually did a test on the stator according to the manual I have and it tests ok..but is it really.As for a air leak..don't know..Carb has new gaskets where required.Carbs were cleaned twice and is clean..jets are not clogged either,screen filter is clear also.Compression is also good on both cylinders..135 psi.Trying to figure out this air leak theory of yours Ding..scratching my head now...hmmmm!!!
 
Which carb is on it, is it a twin with 2 carbs? . . . you mentioned carbs as in multiple carbs . . .
 
I actually am going to purchase the same exact motor tonight.I will hear it running at the guys place first.He wants $375 for it.Then I can try parts from it on my motor to see if I can solve the issue.Like switching coils and switching stator,switching hoses and tanks and just to see if my original motor will run like it should..then I'll know maybe what the problem was..could sell it then or keep as a backup anyways.Will keep you updated Ding.Larger pic ..have to find where I can findone..
 
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well Ding..I thought I had it licked..but didn't happen that way.Bought the other motor,heard it running in a barrel of water..sounded good..idled good.Took it home and threw in my barrel and sure it idled but was all over the place when engaged at higher speeds.Now I am feeling really bad being this guy ripped me off to.Tried many things,re-gapped breaker points,switch fuel pump parts,replaced pulse line,cleaned carbs.Still started hard..idled ok but when I gave her gas she starting surging again..not a constant.Then decided to pull cyl #1 plug and motor didn't change. :o| #$%&* the coil was not firing.. :o| :o| .SO took coil off the first motor I had and nothing changed much,found a frayed wire between the 2 coils and swapped and no change.I just about had enough of this crap and went inside the house a while.

Went back into the garage and decided to switch stators from the 2nd motor to the first.Put the coil back on the first one also.I checked point gap as well and was ok.I did a link and sync earlier so that should be fine.Just wanted to know what was going to happen.WOW to my surprise she fired up in a couple of pulls..and ran well at the start position.Then I proceded to idle it down and WOW she idled..Gave her throttle in gear and she is running true to form..smooth and all.Now I will keep the other motor for spare parts,,prop,driveshafts,pump,gearing,and the motor..it cost me $375 to fix the problem.If I had to order a new stator..it would be anywhere from about $300 to $450 plus shipping..so I guess I am a little further ahead since I have a lot of spare parts.Will switch bottom ends because the first guy must had hit a rock and tood a chunk out of the fin below the prop.Also first motor is clean to boot inside,2nd motor is full of oil everywhere.being it must of been used alot.
Still drives me :o| that the first guy only sold the motor and boat because he didn't want to spend the $$$ on a stator...and the 2nd guy also had issues..same as snowmobiles..some guys just love to sell you crap and make money on it.Good thing I don't give up easily and keep at it..with a few #$%&* words to boot and the friggen heat we have here..I almost lost it.Was going to at 1 point toss both motors into my Pond out back.Thanks for your help anyways
 
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well I am still impressed with the motor now.Changed bottom end today and changed lower end oil.Purrs and starts 1 to 2 pulls and runs smooth...never give up on something and love it when I can fix an outboard which I have never worked on before.Bring on a Flood!!!!
 
bluemonster1 said:
well I am still impressed with the motor now.Changed bottom end today and changed lower end oil.Purrs and starts 1 to 2 pulls and runs smooth...never give up on something and love it when I can fix an outboard which I have never worked on before.Bring on a Flood!!!!
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Very nice! Thats one of the things i love, taking on somthing you have no clue about and figuring it out and making it work. I always say, "you learn somthing new everyday, when you think you know it all, its time to step away". (cause you really dont, there is always more). Way to go Blue!!!
 
thanks..as usual when working on something first time..it is good to get a manual with all the procedures and specs.Downloaded a manual for like $7 a while back..My wife tells me that I am persistant and will die trying.,,lol.Yes I don't give up to often and it is a learning experience for sure.Almost gave up on it ..but struggled on.And the best part is when you hear it running at the end.Same thing when I rebuilt my SRX and SXR motors.A lot of work for me at the time,but with manual and info and taking my time..it turned out positive..
A note to all newbies on here..before you start a rebuild of any sorts on your sleds..load up with info and a manual and understand what you are up against and follow step by step and you will get there.Don't try to cut corners because it will bite you in the end..do it right and when you are stumped..call on us TYer'"s .A manual will assist you and you won't have to start a new thread on every aspect of your rebuild..... ;)! :rulez

PS: wasn't there a thread started on here last season that was addressed to newbies and had references to everything they needed to know and read ahead of time..was it you super1c ????
 
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Well blue I was going to suggest to you that it was your tub of water that was giving you problems LOL!!!!


JK I'm glad you figure it out never give up, never surrender LOL!
 
yep changed the water..Now motor runs good with the cover off..here is a new issue I can't solve..If I put the cover back on ,,the motor becomes un responsive.Turn throttle and the rpm's won't climb.She is smokin like mad aslo.Seems to be in a choke mode.Yet remove cover and throttle response is back and revs rapidly from idle to fast.The cover is totally sealed to prevent water from entering..but how does carb get its air at faster speeds then.This is weird and starting to really drive me nuts now...lol..Do I take a holesaw bit and and start drilling holes in the cover or what...lmaorof... :o|
 
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