1st boat 73 merc 850 wont rev.

[merc850]

Trigger T/S

 

[Ghost1958]

Trigger T/S

Thanks Merc850.
Checked it out some today. Electricals check out except I can't do a running high speed test. One can't drive the boat and do that test. Two it has only ran WOT twice for about 5 min since I owned it.

Have solid blue spark across a gap tester. Didn't have fuel. Apparently the electric pump at 5 lb doesn't have enough ummph and air locked.
The carbs backdrained some very orange has when I took disconnected the line at the inline filter.
No idea where that came from.
Gas mix in the tank is fresh. The motor hasn't sat just doesn't run right.

Anyhoo I took out the electric pump put the bulb back in rehooked up the onboard fuel pump, got the Orange gas out using a suction pump to backfloe the carbs then primed with good Gas and gas went to the carbs.

I'll be on an idle speed only lake Monday. The distributer may get that oil in it again If the motor actually starts and I use it to move around some. If so I'll take a photo of it.

I'm tempted to remove those filters in the carbs as has been mentioned but not sure if id need new gaskets or something to put the caps back on.

It will cost me about 160 bucks to have top and bottom seals put in and another 80 plus parts to rebuild the carbs.
Can't afford that so soon after buying the boat.

Looking to sell a trike kit off my bike to fix the motor I guess.

Oh I did try blowing thru the fuel line before back flowing the carbs. I couldn't blow air thru. At all.
Motorcycle or car carb I would have been able too.

Not sure if these carbs should let me blow thru them or not. But gas is definitely going to them using the bulb now.

 

[Ghost1958]

Update. Ran motor on muffs today .

Primed it , choked cold idle lever etc and it started.
I noticed the gas in the filter was that odd red color but a few pumps of the bulb and it went on they.
Motor ran but wouldn't idle. Set the idle stop up a bit to get a steady idle , shifted into forward , no clumnks etc just a slight click and in gear.
Checked each plug running with gap testor.
Good blue spark on all cylinders.
I have noticed now that after it sits not running the fuel seems to back off partly emptying the transparent filter .
Once that occurs it's like starting it cold for the first time. Choke, cold idle lever etc.
Or pump the bulb a couple times and it'll fire right off which makes me think maybe my bulb is leaking off and needs replaced,???

Could a bad bulb cause all this no WOT bad idle etc???

I'll be in lake tomorrow . idle only but I'm thinking my idle and shift point should be much different on muffs compared to in water??

 

[Mercurylips]

Ghost- I'll toss this out to you just to give those with all the right knowledge time to answer. Your motor may not run well under a load just because it ran and sounded decent on Muffs. Abad bulb would probably not cause the motor to fail to go wide open unless there was an obstruction. A bad bulb can cause a great deal of headaches, however. I suffered through a half season trying to get to all the problems my old 500 had. Finally got it figured out and now it runs hard. Still have projects on it but I can go out and not get stranded. This forum is a great help.

 

[Ghost1958]

Ghost- I'll toss this out to you just to give those with all the right knowledge time to answer. Your motor may not run well under a load just because it ran and sounded decent on Muffs. Abad bulb would probably not cause the motor to fail to go wide open unless there was an obstruction. A bad bulb can cause a great deal of headaches, however. I suffered through a half season trying to get to all the problems my old 500 had. Finally got it figured out and now it runs hard. Still have projects on it but I can go out and not get stranded. This forum is a great help.

Thanks. That it started at all is better than the last time I had it out lol.

I'm not sure where the bright orange fuel in the carbs comes from. Thought I had pulled it all out with the vacuum pump.

I'm aware it probably won't throttle up much under load but I think I'm narrowing it down to fuel delivery pressure. As it's throttled up the transparent inline filter doesn't stay completely full. As if there isn't enough pressure to keep up.

A 5psi electric pump wouldn't keep up at all so I can only assume the onboard pump if working optimum puts out more than 5 psi.
I'm just hoping my idle and shift are about the same give or take a little as on muffs.

 

[Ghost1958]

Update I went to idle speed only lake today.

Boat started up, had to warm it up a while cuz it kept dieng when in gear.
Little bit it went in throttle up a bit a went to the head of the lake. Fished a few coves, motor kept getting harder to get in gear without dieing.

Noticed had to prime the bulb Everytime . It would be soft like it had sat for a week in about 10 min.

Finally motor would start but die in gear Everytime.

So drift fished and used trolling motor for a few hours winding up at the dock.

I think among everything else the bulb is bad. And I bet when I look it'll have that oily stuff in the distributer again. Was to dark when I got back.

On just fast idle lever it will finally surge and slow the go to 4000 rpm in neutral. I cut it back to about 18 to warm,up but it acts like it's not getting enough fuel pressure.

Im kinda at a loss. I don't have the know-how to pull the top seal, or the distributer and no idea where to find a readable manual.
Gonna change Bulbs. If that don't help it guess it's a black boat anchor and I'll just part it out.

 

[Ghost1958]

Talked to a former Mercury tech today.
He works at a national park marina now.
Is 120 dollars a decent price for replacing top and bottom seals, and rebuild carbs????

That price includes labor and parts.

 

[Mercurylips]

Yes- very decent. And buy a new tank bulb.-Mike

 

[Ghost1958]

Yes- very decent. And buy a new tank bulb.-Mike

He's giving me a new tank bulb.
I'll put it on before I take it up there. Figure to go fishing one more time while I wait my turn. Likely be using the trolling motor mostly though.
Thanks for the reply.

 

[Mercurylips]

I had a thought about the orange colored gas. Was wondering if the motor had used a lot of leaded gasoline in it's day. Just a thought. Also. If it were mine and someone was doing my carbs, I would try to make sure they have new carb floats and you can get them sent to you in about 7 days or less from I Boats. Good luck and please let us know how it all turns out.-Mike

 

[Ghost1958]

Update on my 82 astroglass 15.5 ft bass boat and it's 73 Merc 850 outboard .

Boat remains perfect. Mostly because only fished with the trolling motor a few times.

The motor I'm sick of. Had new top bottom seals put in, carbs redone few other things.
Put it in the lake didn't get quarter mile same thing.
The mechanic came down to the ramp got in it with a helper, got it to work about two min and died. Towed back.
No spark now, or fire at all anyplace.
I hate the motor. Been three months trying to fix it. Swapped it to the mechanic as a parts motor and 200 bucks for a 79 model 70 HP guaranteed Johnson.
The swap includes the tech servicing the motor completley , mounting it and all controls, adjusting cables, carb rebuild though it is a running engine just off a houseboat at the marina.

Sorry Merc folks that tried to help me. I appreciate it but it'll be winter if ever to get the boat usable messing with this old Merc.

I lose 15 HP but I get a newer model known good guaranteed Johnson motor ready to fish in the next week.

Pretty sure the 70hp will be plenty to fish with, on a 15.5 ft fiberglass boat.

 

[Chris1956]

Well, that's too bad. Your merc was/is a good motor. The ign system is a dinosaur, but the rest of the motor is just fine.

FWIW, I think your electrical/ign system was the problem.

 

[Ghost1958]

I personally think it's the coil. Mechanic thinks stater but I don't believe the stator would have to function with a hot battery, plus the battery is charging.
But the tech is a friend charging little to nothing labor so I can't push to far.

But, even if I could have found a good coil and got it running, it has no reverse, all the insulation was off the stator wires that I replaced with shrink wrap. But I couldn't get inside the stator so it'll likely be next.

Probably could have fixed it finally but we are making payments, granted small ones on a boat we haven't been able to use since early spring because of that motor.

So swap for the Johnson, which I can work on myself with bro on laws help if needed later on after guarantee is over and use the boat before I need a keel plate to break ice.

But again thanks for all the help.

 

[Chris1956]

The stator only charges the battery on that motor. It is independent of the spark. The coil is cheap and easy to change, but they do not fail very often. They are avail aftermarket, but get the right one (for battery powered CDI ign).

Best of luck with the Johnny...