1967 merc 650 4cyl help

[Fuzzytbay]

Re: 1967 merc 650 4cyl help

There are a number of reasons the bottom carb doesn't seem to be doing its thing, but first off your right, don't sink money into it, untill you know if there are "expensive" problems. Rebuilding the fuel system is pretty cheap, so find the compression readings, then if they are good, its on to the next step.

 

[towman17]

Re: 1967 merc 650 4cyl help

ok so the manual still hasnt arrived..i did a compression check and if i did it right there is just a little over 90psi on all 4 cylinders..sounds a little low to me but its even on all 4..the 2 upper spark plugs showed little wear but the bottom 2 had no wear at all..still shiny new..without having the manual that i ordered i have no idea what the problem could be or what to look for next..any ideas what i should be checking and how??

 

[SeaKaye12]

Re: 1967 merc 650 4cyl help

First off; I hope you don't get discouraged and junk your motor. From the compression numbers...it seems that while they are a little low...it also seems that the block is in decent shape. Maybe your gauge just reads low.....

If spraying fuel or "carb cleaner" into the bottom carb produces no effect...I would think that it means that those two cylinders are not firing. So; direct your testing to the ignition. You may see a spark outside the engine when you crank it over with the spark plug wires disconnected; but it may be too weak to fire under the cylinders' compression. Look for a fat blue spark that can jump nearly a 1/2" gap.

The clean as new plugs would confirm that they're not firing; but shiny plugs can also indicate water intrusion.

Good luck solving the electrical issues. There are a lot of people on here who really know the older engines. You can look back over posts that deal with the distributor ignition engines like yours and see how to test each and every part of it to isolate the issue and prevent you from ordering expensive and maybe un-necessary parts. Start by looking at each and every connection. Check wires for corrosion and check and re-check all your ground connections.

Post back your progress...

Chuck

 

[Fuzzytbay]

Re: 1967 merc 650 4cyl help

..i did a compression check and if i did it right there is just a little over 90psi on all 4 cylinders..sounds a little low to me but its even on all 4..

Even is good......
As for the numbers, well if the gauge is off, they might be even better? right
if its on 90's still ok. It is more important to be even.
Sounds like time to take off the carbs and get kits and clean them.

 

[towman17]

Re: 1967 merc 650 4cyl help

so if the lower 2 spark plugs dont seem to be firing then what should i check for next?? could it be bad grounds?? any other wiring?? magneto?? also i just noticed when i was looking at the distributor cap the redish colored part that the cap connects to has a small crack going up the side of it..should i put the at the top of the list for things to check and replace? i tried looking for the cap and that redish piece and other ignition parts online but found nothing except the cap at one place for 270.00 american plus shipping..it says that the cap is no longer made so im guessing the rest of the ignition parts will be just as hard to find and be really costly..

 

[Leahcim]

Re: 1967 merc 650 4cyl help

Hi Folks,

I'm looking for a service manual for a 1967 merc 650. Of course a free download would be best but I'll buy one if freebies aren't available. Specifically, I'm looking for the wiring diagram for connecting the remote control to the motor. The motor has bare wires hanging out the hole where the plug used to be (I think) and the control wires have also been cut. The colors don't completely match up so I need to know what wire does what on both the control end and the motor end. The control is a "MercControl" but evidently it's not the original control, unless the color mis-match was the original situation.

Mike

P.S. I tried the links in the "sticky" thread to no avail. Also did a google search - still trying.

 

[Leahcim]

Re: 1967 merc 650 4cyl help

Found what I needed. $5.00

http://www.instant-manual.com/1965-2004_Mercury-Mariner_Outboard_Service_Manuals.html

 

[194269]

Re: 1967 merc 650 4cyl help

Hay guys, this is a 1967 650, they where all built with thunderbolt ign. Which means no J-6-J plugs, the proper plug is UL-77V's or there equal.

 

[merc850]

Re: 1967 merc 650 4cyl help

Here's a site that deals with old Mercs http://johnsoldmercurysite.com/phpBB3/index.php if you want to put the original wiring harness back in here's one http://www.iboats.com/mall/partfind...gd_poid=334870&gd_row=25&**********=456347146 but you'll have to find the control box wiring somewhere, try ebay.

 

[Leahcim]

Re: 1967 merc 650 4cyl help

Thanks merc850.

More questions. I think I'm on the path to the second happiest day in a boat owner's life. 8^)

When I put the control (remote) in the forward position, I can turn the prop clockwise but it clicks when I do so. In neutral the prop spins freely in both directions, in reverse the prop turns a small amount but then won't turn anymore in either direction. Is this normal behavior?

Also, I can't see a rectifier, nor a stator of any kind beneath the flywheel. Does this mean the motor will not charge the battery while it's running? I haven't ran the motor yet except for 15 seconds or so before I bought it so I haven't measured the voltage across the battery while it's running. I need to buy some ear muffs before I test start it and they're hard to come by where I live (Mexico). I may resort to a cut off garbage can full of water. It's an electric start motor, no pull cord but I can wrap one around the flywheel if I take the housing off.

Serial number 2211060

 

[merc850]

Re: 1967 merc 650 4cyl help

The prop behavior is normal except you shouldn't shift into reverse when the engine isn't running.
There was another post I read about an electric start without charging system. the battery is for starting only in this motor so it must have the KD4 magneto-a magneto makes it own spark internally. You'll have to charge the battery with a charger. If you look in the manual it will tell you how to set the points and set the timing. Take the cowling off and take/post some pics.

 

[Leahcim]

Re: 1967 merc 650 4cyl help

Thanks again 850. I don't know if I mentioned this before, but this is a new old boat. Haven't had it in the water yet. Just discovered the key doesn't return to the ON position from the START position. I'll just do it manually. No biggie I guess. Right?

I'll be using the boat in Baja (Mexico) at a spot where there isn't any 120 VAC around so I'll have to charge the battery with a solar panel.

We'll see what problems tomorrow brings. It's Miller (Tecate) time here now.