Force 40 hp mostly fixed - starter and carbs

[screeminreelz]

First off, I would like to say that without the knowledge on this forum I couldn't have fixed my motor as fast or as cheaply as I did - Thanks guys!

I have a 1992 Force 40 hp that was idling rough and not going into gear without stalling. I checked the compression and both cylinders were 125 pounds, which was a big relief. So then I took the carb off and cleaned it and re-installed it. The motor ran pretty good, but a little rough even with tuning so I ran some SeaFoam through it to clean the deposits. By the end of the treatment it ran a lot smoother.

Well, with that fixed I had another problem - the starter motor was getting weak. I tried two batteries, fully charged, and it still wouldn't turn. I took it apart and the brushes were worn at an angle. The commutator had a black varnish on it as well. So I scraped the commutator back down to copper, turned the brushes over so the factory flat side was up, cleaned the slides, and stretched the springs a little. Then I cleaned everything with carb cleaner and let it dry. I put it back together and shined up the connections with emery cloth. The starter was strong! Cost - $0 and about an hour of dinking around thanks to this forum.

The one issue I have still is that the recommended plugs are surface gap, but the motor will not run on them. I bought new ones and it will run, but only sometimes and with a lot of cranking. The standard plugs work great. Anybody have an idea why, or how I could fix it so it would run on those plugs? I heard regular plugs could be too hot for the motor, etc., so I would like to get it going with the sg's if possible.

Thanks again to all the people with knowledge willing to share on this forum. Remember, if you fix your boat - post the results so everyone can benefit. It is easy to fix it and then go boating and not follow up, but it is important so that people with the same problem will know what worked.

Brian

 

[jerryjerry05]

Re: Force 40 hp mostly fixed - starter and carbs

QL-76 V Is what the factory put in it.
I think it's a gapable plug????

 

[screeminreelz]

Re: Force 40 hp mostly fixed - starter and carbs

I did some digging and the recommended plug is L-76 V which is surface gap. I am running L77JC4's in it now and it is fine, but it will not work with the L-76 V's. What gives? Weak coils maybe; could it be a timing issue?

 

[screeminreelz]

Re: Force 40 hp mostly fixed - starter and carbs

>>>

 

[Jiggz]

Re: Force 40 hp mostly fixed - starter and carbs

According to the drawing it can either be a L-76V (surface gaps) or the QL-76V (gappable). I'll say just stick with the QL-76V if it works. Obviously, the difference between a SG and gappable one is the timing as there is a difference in the gaps, and the coil types. If it works perfectly with the QL76V I don't see any problem why you cannot continue to use them. This is pic of a QL76V

http://compare.ebay.com/like/120916095925?var=lv&ltyp=AllFixedPriceItemTypes&var=sbar&_lwgsi=y&cbt=y

 

[screeminreelz]

Re: Force 40 hp mostly fixed - starter and carbs

Okay, so if my motor runs great with gappable plugs that means I have a certain coil type on my motor made for those specific plugs? And also if there is a different timing sequence than if I used SG's - What timing should I have then?

 

[Jiggz]

Re: Force 40 hp mostly fixed - starter and carbs

Can you provide the serial number of the motor? have you tried the QL-76V? I understand you are now using the L77JC4's which are working perfectly. The "Q" in the QL76V stands for electronic ignition which is common on CDI ignition system. Come to find out these are also surface gapped. As for your question about the ignition coil, yes the coil type is directly related to the plugs used. Unless the ignition coils have been modified or replaced with non-oem coils, the recommended plug is either L76V or the QL76V and the only difference between the two is the RFI Radio Frequency Interference suppression of the "Q" series. I do not believe this will affect the timing. As for most outboards, the timing is almost static at 34 and dynamic at 32.

 

[screeminreelz]

Re: Force 40 hp mostly fixed - starter and carbs

Jiggz, the serial # is OE064165 and I have not ran the QL-76V's, only the L-76V. I ran the L-76's last night on it, and it ran fine off the bat but when I shut it down and tried to re-start it was like they were fouled. The L77JC4's fire up multiple times, as they should. The motor is not quite right yet, though I am wondering if I have other problems than just the type of plug my engine likes.

I have tested the spark and it looks good. It jumps a 1/4" gap to the block. Compression is good. Re-did the carbs twice but it still seems like I have fuel issues so I ordered a new needle, seat, and bowl gasket. New float on the carb, but it seems like this one is different from the last one. Wondering if that is an issue, but the part number is right per the exploded diagram. I have it narrowed down to fuel and timing, but I am far from an expert. In a perfect world I could get the issue fixed so that I can run surface gap plugs without trouble, I guess. Is my motor able to run both QL76V and L76V or is there a specific type for the hardware on my motor that makes one better than the other?

 

[Jiggz]

Re: Force 40 hp mostly fixed - starter and carbs

You can ran either QL76V or the non-suppressed L76V. If the L76V gets fouled it sounds like you have your idle mixture screw set too rich. Usually this is only set around 1~1 1/2 (initial is 1 1/4) turn from slightly seated. This is probably the reason the gappable plugs work better because they don't usually foul because of the gap.

And I understand why some people prefer a richer idle because of the fear of piston or cylinder melt down. However, it does foul the plugs if it is too rich. There is a link and synch sticky post to properly set the idle mixture screw. And then try the L76V again, after cleaning them up. Mine are basically at 1 1/8 from slightly seated.

And after running the plugs don't have wetting on them although they are not bone dry. There will be a little sign of dark browning around the perimeter of the plug surface but not entirely. A little wetting (but not dripping wet) is also acceptable as long as it doesn't create carbon build up on the entire surface of the plug.