1965 merc 650 wont start, tries to start but backfires

[GA_Boater]

Re: 1965 merc 650 wont start, tries to start but backfires

I don't think you are in reverse. Does the prop prop turn at all with it in that position?

What is your serial number?

BTW - Nice shoes.

 

[anw34]

Re: 1965 merc 650 wont start, tries to start but backfires

1670893 is the serial number n no it does not turn in either direction I can take a screw driver n push it forward thethen all the way forward is forward no spin left and spin with clicks to the right. So yea that's reverse lol. N thanks haha

 

[anw34]

Re: 1965 merc 650 wont start, tries to start but backfires

I meant to say one click forward is neutral then all the way forward is reverse

 

[GA_Boater]

Re: 1965 merc 650 wont start, tries to start but backfires

I thought something was wrong. When I looked at the pic, your linkage is totally different than mine. You have a '64, not '65 Merc 650. The shift linkage changed some about that time.

Anyway - The parts link your motor - Mercury Marine 650 (4 CYL.) Outboard Motor Parts by Component

Sometimes your have to spin the prop to get it to go into reverse. That's to get the gears and shift dogs lined up. Make sure the remote is in the same gear when adjusting the cable barrel. Can you get neutral, where the prop spins in both directions? Like I said - that's where I adjust the barrel on the cable.

 

[anw34]

Re: 1965 merc 650 wont start, tries to start but backfires

Yes I can get neutral but if I put it in neutral or forward the cable won't go on I have the barrel adjusted all the way forward towards the plastic part of the cable the part that slides in n out. With it adjusted all the way in is the only way I can get it to slide on the pin and that is with the lever in forward position so that the lever is as far forward as it can go and the only way it will go on the pin is if I have the pin on the motor slide part in reverse so its back enough for the cable to slide down on the pin. So once its on it won't move any more forward and if I put the lever in reverse it makes it go 2 inches past the pin the the back. Plus even if I take the cable off and remove the lower end the sliding pin won't go any further back cuz at the top of the shaft inside the motor part where the little bent rod going from the slider to the shaft. The upper shift shaft has a plate on it right below the arm the connects the bent arm and the little plate that's welder on that kinda looks like a triangle hits the motor when I turn the shift shaft counter clockwise so going to reverse when the plate hits making it stop it only goes to about the middle of the slide zone like it is in the picture. So that's why I was thinking the bent rod going from the upper shift shaft to the slider pin is too short or its the wrong upper shift shaft. Hope that all makes sense

 

[anw34]

Re: 1965 merc 650 wont start, tries to start but backfires

Lever all the way forward motor in reverse

 

[anw34]

Re: 1965 merc 650 wont start, tries to start but backfires

http://i57.photobucket.com/albums/g2qb333/IMAG0902.jpg[/IMG
[IMG]http://i57.photobucket.com/albums/g232/qb333/IMAG0902.jpg
lever in neutral motor in reverse

 

[anw34]

Re: 1965 merc 650 wont start, tries to start but backfires

Lever in reverse motor in reverse

 

[anw34]

Re: 1965 merc 650 wont start, tries to start but backfires

Lever forward motor forward

 

[CharlieB]

Re: 1965 merc 650 wont start, tries to start but backfires

The prior owner may have had the shift cable off while installing the LU. The motor side of the linkage is indexed incorrectly to the LU.

Drop the LU, leave the shift cable disconnected, slide the shift linkage to the center of its slot.

Reinstall the LU in Neutral, you may need to turn the flywheel to align the crankshaft splines.

Now the linkage should be centered, readjust the cable trunion such the cable fits with the shift control in Neutral.

Retest shifting. You may have to fine adjust the trunion to ensure full engagement in Reverse.

 

[anw34]

Re: 1965 merc 650 wont start, tries to start but backfires

Well I got it to shift and everything just fine now but took it to the lake last week and started it up and it didn't want to idle but if it take off the cover that wraps around the motor it will idle fine. So today I went out n messed with it and i set the Carb needles to make it run at the highest idle I could with the cover off and when i put the cover on it idles real low n wants to die unless i put the idle lever all the way up. I notice that the smoke from the exhaust that is out the back of the motor is leaving smoke in the engine area like at the back there is a gap around the engine and the upper cover is there supposed to be a seal there so when the wrap aeound cover is on some of the exhaust fumes go up in the engine area and Idk if that is choking it out and killing it or its not getting enough air to the carbs when that cover is on. Any ideas? By the way when I was on the lake I ran it all day without the cover on and it ran fine all day

 

[CharlieB]

Re: 1965 merc 650 wont start, tries to start but backfires

You have a gasket leaking exhaust fumes inside the cover.

Most likely the base gasket between the powerhead and the midsection.

Find a spray bottle, put an inch of liquid dish soap in and fill with warm water to help mix well.

With the motor at a moderate to high idle spray all around the lower end of the motor block looking for soapy bubbles to form, indicating the leaking exhaust.


The idle mixture is now too lean, it must be set to 'Best Idle' while IN the water and IN Forward gear. Even then it must be even further richened to provide the additional fuel necessary for good acceleration. But this needs to wait until that exhaust leak is cured.