1985 Force 50 no spark and parts question.

[aarivers]

So I'm down to the point with my project boat that it's time to try and start it up. No telling how long this thing hasn't ran. I replaced the water impeller and changed the lower unit oil. Also had to replace the fuel hose as the old primer bulb and hose were shot.

So this weekend I get some time to try and start her up. Attempt 1: get it to crank, choke solenoid works, no start. Attempt 2: same thing. So I get my dad who's on vacation to help m crank it while check for spark at the plugs, by grounding them out on the block. No spark on either one. Hmmm. I double check my wiring and everything looks right. So I take the flywheel off and looks like the points aren't opening correctly or the gap isn't set right, plus they are really dirty. I clean them up with some 400 grit sandpaper and set the gap to .020 (did a search on here and found that as the correct gap in a thread). I put it all back together and attempt 3: Tries to start a couple times, I can see fuel sometimes spitting out the front of the carb and sometimes the motor wants to kick back. I get my dad to help me check the spark again, this time I have spark on plug #2, no spark on #1 though. Swap the coils around, no change, swap plug wires and plugs, no change.

So with all that out of the way, I think I have some bad points or condenser. Sound correct to you guys? This is my first boat, and first engine with points, so I'm in some murky waters here. I was going to replace the parts but everywhere I look the tune-up kit FK1075 is discontinued or sold out. Where can I get parts to get this old dog running at?

Thanks,
Aaron

 

[oldboat1]

Re: 1985 Force 50 no spark and parts question.

It may be worth taking the flywheel off once again, and resetting everything once more (loosen coils, points, condensers and all connections one at a time, and retightening them.) Use an emory board on each of the connectors before reattaching, then reset the points again (no more than .020). I think you can get the points and condensers through NAPA, and maybe the coils if you want to go the replacement route, which really is the best approach -- or can give Ebay a shot for NOS parts. Clean the plug wire connections -- running a Phillips screwdriver in the spring connectors can work, followed by electrical cleaner spray if you have some (spray is a good idea on all the magneto connections, but doesn't replace good old fashioned scraping and polishing.)

btw, if you go back under the flywheel, make sure all of the wiring is tucked in and is not contacting the flywheel -- could explain some of the symptoms you describe. Also, IBoats is a source for replacement parts.

 

[aarivers]

Re: 1985 Force 50 no spark and parts question.

Okay so i found a set of NOS parts on ebay for the points and condensers. I installed them tonight but before i put it all back together I wanted to take some pics and make sure everything looks good to you guys. There's one wire that I'm not sure is supposed to be in there or maybe I'm missing a wire. Anyways on to the pictures.

Full shot. Now originally there was a blue wire running from the screw that holds the left condenser to plate, and it ran to the connection of the black and white wires are connect. I removed it since the other side has no wire, I'm hoping someone can tell me if it's supposed to be there or not, or if there is supposed to be a wire on the other side like it.

This is how I set my points. When that mark is inline with the black piece like in the picture I have a .020 gap in the point. I don't have a manual so i have no clue if this is how they are supposed to be set. So input on this would be appreciated also.

 

[pnwboat]

Re: 1985 Force 50 no spark and parts question.

According to my manual, the points on the 50HP motor should be set to .015. Also, I believe that the blue wire on the right condenser should connect to the terminal on the points just like the one on the left. See Red arrow.



I don't think that there should be a wire that runs from the condenser mounting screw to the terminal where the black and white wires are connected. That would ground out the points.

 

[aarivers]

Re: 1985 Force 50 no spark and parts question.

According to my manual, the points on the 50HP motor should be set to .015. Also, I believe that the blue wire on the right condenser should connect to the terminal on the points just like the one on the left. See Red arrow.

I don't think that there should be a wire that runs from the condenser mounting screw to the terminal where the black and white wires are connected. That would ground out the points.

Thanks for the information. I will gap the points to .015 then before I put the flywheel back on, I guess I'm doing it right when I set them at that mark on the cam? The blue wire on the right is actually going to where you pointed with the red arrow, it's just under the black wire and not visible in that picture. As for the other blue wire, looked like it would ground it all out to me too, that's why I removed it, also there was no matching wire on the other side. I miss electronic ignitions..

I'll post an update tonight after I try her again.

 

[pnwboat]

Re: 1985 Force 50 no spark and parts question.

Yes you set the points on the index mark on the cam to adjust the point gap.

After you set the point gap you're supposed to check the timing. Setting the timing is pretty involved and the manual says you have to use a special tool that threads into the spark plug hole. Maybe some of the other experienced folks can chime in on how they set the timing on the older points type ignition systems.

 

[aarivers]

Re: 1985 Force 50 no spark and parts question.

Yes you set the points on the index mark on the cam to adjust the point gap.

After you set the point gap you're supposed to check the timing. Setting the timing is pretty involved and the manual says you have to use a special tool that threads into the spark plug hole. Maybe some of the other experienced folks can chime in on how they set the timing on the older points type ignition systems.

Anyway you could scan those pages from the manual for me on setting the timing? I have set car timing but never a 2 stroke boat engine, so any help would be appreciated. I tried to find a picture of under the flywheel on other peoples Force motors to compare to my wiring but google images didn't deliver.

 

[Frank Acampora]

Re: 1985 Force 50 no spark and parts question.

Here is the operation of a battery powered points ignition: From the ignition switch "I" terminal, power is supplied constantly to the positive terminal of the coils. The white wires on the negative terminal of the coils go to their respective points. With the points closed, voltage flows through the coil to ground, creating a magnetic field around the coil primary. When the points open, the primary field collapses through the secondary coil windings inducing a very high voltage pulse to jump the spark plug gap. The opening of the points controls how long they are closed and sets the "dwell" or amount of time the coils have to build up a magnetic field. Too little or too much dwell will reduce the ultimate high voltage pulse.

Condensers absorb the voltage flow through the coils when the points open, reducing sparking and extending point life. A shorted condenser will prevent sparking. No condenser will also prevent spark.

As far as timing, the manual calls for special tools but it can be done without them. Set the top cylinder to top dead center by feeling through the plug hole and mark the flywheel and block. set the bottom cylinder to top dead center. Mark the flywheel again. If you did this correctly the two flywheel marks should be exactly 180 degrees apart.

Count the teeth on the flywheel and divide into 360. This gives the number of degrees each tooth spans. Count to the right the correct number of teeth to equal 30 degrees and mark the flywheel for both cylinders.

Since point opening not only sets dwell but also affects timing, both cylinders must be timed and points set to correct it.

Remove and ground both plugs. Starting with top cylinder, set the control box to wide open throttle. with the ignition key on, turn the flywheel slowly by hand and see where the plug fires. If it fires on the 30 degree mark, then timing is correct. If not, adjust the rod from the timing tower to the points plate under the flywheel.

Now check the bottom cylinder. If it is not within 1 degree of the top, then adjust the gap on the points to bring it into adjustment.

 

[aarivers]

Re: 1985 Force 50 no spark and parts question.

Thanks for the information Frank! I'll get this all looked at tonight when I get home from work. When it did try to fire the other night it was kicking back, so to me that means it's definitely off time.

 

[aarivers]

Re: 1985 Force 50 no spark and parts question.

Well following the good advice here I took another shot at getting the engine running tonight. With the help of a friend I got the gaps set, timing set and spark checked. Then it was the moment of truth. IT RUNS! This engine probably hasn't run in over 10 years. I have to wonder who put that wire from the condenser ground to the point wire. So I still have some more tinkering to do with it, as of now it will just idle, and only if I hold the choke in, so to me that means it's not getting enough fuel. I'll take the carb apart this weekend and also check the fuel pump and filter also to see if I can get it to idle out right and take some throttle.

I had my trusty camera man there to record the momentous occasion.

 

[Nordin]

Re: 1985 Force 50 no spark and parts question.

Just an information about not using the factory timingtool that screws in to #1 cyl. to adjust the timing at WOT roughly.
You can use a caliper and measure the pistonposition. On these 35-55Hp engine 30 degrees BTDC is 0.264-0,276 in (6,7-7milimeter).

Measure with a caliper to a surface at powerhead when piston is in TDC... this is zero degrees. Add about 0,27 in and there is the distance for 30dg BTDC. At this Point the # 1 points shall open at WOT.

Then you make the fine adjustment with a timinglight.

 

[aarivers]

Re: 1985 Force 50 no spark and parts question.

So I'm pretty sure I found the source of the fuel starvation issues.. Hmm, that doesn't look like the stock bolt configuration, no wonder it was leaking fuel like a faucet.

The bolt is about 1/2 inch too long I imagine.

So why such a long bolt? Oh here's the answer. Stripped out threads at the hole entrance.

And with the bolt all the way in like they had it, the main jet hole is covered up, only allowing a little gas around the threads.

So now I get to figure out how best to repair all this. I guess the real way would be to get a tap and die to cut some new treads in it for a little bit larger bolt. What say you guys?

 

[pnwboat]

Re: 1985 Force 50 no spark and parts question.

Congratulations...It's alive! If there is enough material to drill it out and tap it, that would be the thing to do. Just drill it out deep enough for a larger bolt if that's possible. Might want to look at the fuel pump diaphragm too. If it's been sitting for that long it's probably shot. I would also replace the water pump impeller too to be safe.

 

[oldboat1]

Re: 1985 Force 50 no spark and parts question.

wow. would not have been able to confirm wiring, but proof is a running motor! appears to be good sleuthing on the bolt holding up the carb bowl. I also think tapping for a shorter but larger diameter bolt is a good plan, along with a gasket/rubber washer to seal it in place. While you are in there, you will probably want to thoroughly clean the carb -- particularly after that tapping operation. And as was pointed out, it would be time for a water pump replacement. Next time you start it, you will want to have the lower unit in a test tank with the new impeller. Really nice job in bringing that rascal back to life!

 

[aarivers]

Re: 1985 Force 50 no spark and parts question.

wow. would not have been able to confirm wiring, but proof is a running motor! appears to be good sleuthing on the bolt holding up the carb bowl. I also think tapping for a shorter but larger diameter bolt is a good plan, along with a gasket/rubber washer to seal it in place. While you are in there, you will probably want to thoroughly clean the carb -- particularly after that tapping operation. And as was pointed out, it would be time for a water pump replacement. Next time you start it, you will want to have the lower unit in a test tank with the new impeller. Really nice job in bringing that rascal back to life!

It's funny, there's just so much little stuff done wrong I have to wonder who the last person to "work" on it was, and if this thing ever ran. I can certainly say it never ran on this boat. The control cables were backwards, shifter cable was going to throttle and vise-versa, the starter solenoid was not grounded so the starter wouldn't engage, this wire grounding out the ignition point, and then this carb bolt blocking the fuel path. All little stuff, where you fix one thing, then find something else wrong.

Oh and I did replace the impeller on the pump, I have a second video where I ran it in a tub of water for longer and it did have a decent spray of water coming out the exhaust.

The carb was non repairable, you can't see it in the pic, but there was a small crack in the bolt boss, and when I tried to drill it out more and tap it, it expanded to show itself. So I have a used unit off eBay head my way, and will keep this one for parts. I'll update once I get the new one on and hopefully have it able to do a full throttle pull.

 

[pnwboat]

Re: 1985 Force 50 no spark and parts question.

You certainly have discovered and corrected a lot of problems with the motor. I think you might be seeing the light at the end of the tunnel! LOL!

Just keep in mind the fuel pump diaphragm (item 7 below) and the check valves (item 9 below).

Mercury, Mercruiser, Force, etc. - FUEL PUMP - FORCE 50 H.P.

 

[aarivers]

Re: 1985 Force 50 no spark and parts question.

Alright I got the used carburetor installed. And it's alive again! This time you can actually give it throttle and have it not trip over itself. The needle seat and seals in the carb need to be replaced, so if anyone has some tips on how to get that little retainer ring out to get the seat out I would appreciate it. Also the head temp was about 200* after about a 5 minute run, that seems hot to me but I don't know, anyone got some info on how hot they are supposed to run? Thanks for the help guys, it's getting closer and closer to splash day.

 

[pnwboat]

Re: 1985 Force 50 no spark and parts question.

200? seems a tad high. Using the muffs can be tricky sometimes though. You have to get the muffs perfectly centered over the water intake, otherwise it won't supply enough water. If you have a barrel or large plastic storage bin or something similar, that usually works better. Might want to check the thermostat too.

 

[oldboat1]

Re: 1985 Force 50 no spark and parts question.

yup. agree with pnwboat.

 

[aarivers]

Re: 1985 Force 50 no spark and parts question.

Big update!

I got it out on the water today, probably for the first time in 15 years. It was having some issues starting up and staying running while I had the hood on it. So I took it off let it idle some and warm up, then headed out down the river. I went about 3 miles and turned around and came back. It runs great at half to full throttle, anything less than half though and it starts to stall out and will die while trying to idle. I got it to the this point but I'm a little out of my element having never worked on 2 stroke outboards before, I think I may call in an expert at this point to try and get that low idle issue fixed.

Thanks for the help so far guys, it's been educational for sure, and i'll keep you updated on how it goes.