1993 70 HP won't turn over

[ericlindy42]

Hello,

I've been digging through a lot of the older posts to find someone with a similar problem that I'm having. I have a feeling I am going to get a few responses as what I read in the other posts, check compression, check spark, unfortunately I won't be able to do this until April. I'm trying to get a better idea of what the problem could be so I can get right into fixing the boat. Here are the details of my problem.

I ran the boat all summer and it ran fine until my last trip I started having problems with the carb and getting it to idle smoothly. On the last trip of the summer it wouldn't start with the choke so I manually pressed the butterfly valve on the carb to open up just a touch more and it started right up. I did this at the same time someone else was cranking the ignition. After this I went to winterize the boat it wouldn't even start up. I used a little bit of carb starter to no avail. The startor will spin and engage the flywheel as the flywheel will keep spinning, the engine just will not turn over, it doesn't even pop, sputter, or choke. I literally have no smoke coming out the exhaust.

I have checked the Gas, replaced the tank, it is clean. Checked the gas lines, it will squirt out. I took apart the carb and cleaned it up 3 times. It's practically brand-new looking (clean).

I know I can rule out any electrical or startor issues since it will crank and spin the fly wheel.

I'm wondering if it is a vaccuum issue inside not sucking the gas from the carbs? Any advice?

In addition, I have been noticing a bit of black carbon build up/soot that would drip down the outside of the driveshaft housing. It is seeping through the bottom cowl onto the housing.

Please let me know what you guys think or where should I start?

Thanks - Eric

 

[carholme]

Re: 1993 70 HP won't turn over

Eric;

Are you saying that the flywheel is turning when the starter is engaged but the engine, ie; pistons are not moving, only the flywheel?

Presumably this is a Force we are talking about, What is the serial number and model if you have it?

Gerry

 

[ericlindy42]

Re: 1993 70 HP won't turn over

Gerry,

Yes, the flywheel will turn when the starter is engaged, however, I wouldn't say the pistons are not moving cuz if this was the case the flywheel wouldn't spin correct? I believe the pistons are moving hence my thoughts that gas is not being vaccumed to create combustion. Do you think that could be the case?

Yeah, this is a Force, 1993, 70 Hp, made by mercury edition. Off the top of my head i do not have the serial number on hand. I'll have to make a trip to the boat storage and get it. If it will help, I'll shoot over to get it.

Let me know, thanks.
E

 

[carholme]

Re: 1993 70 HP won't turn over

Eric;

No problem, the only reason I asked as your post was confusing about the flywheel turning but not the engine and I was wondering if you may have sheared the key. If the key was sheared the flywheel would turn but not the engine.

Gerry

 

[robert graham]

Re: 1993 70 HP won't turn over

Sounds like a fuel deliver problem, lines, pump, carbs, etc. Start at fuel tank pick-up line and check/clean everything up to and including the carbs, connections, primer bulb, fuel pump. Try draining each carb onto a clean white rag to get an idea of what water/debris may be in them. My guess is that you have a some plugged carb jets or float needle valves that could be stuck. When you get the carb drain plugs out, then pump your primer bulb to pump fuel through those float valves to be sure they're open. Good Luck!

 

[ericlindy42]

Re: 1993 70 HP won't turn over

Sounds like a fuel deliver problem, lines, pump, carbs, etc. Start at fuel tank pick-up line and check/clean everything up to and including the carbs, connections, primer bulb, fuel pump. Try draining each carb onto a clean white rag to get an idea of what water/debris may be in them. My guess is that you have a some plugged carb jets or float needle valves that could be stuck. When you get the carb drain plugs out, then pump your primer bulb to pump fuel through those float valves to be sure they're open. Good Luck!

Robert,

I've cleaned the carb several times. When you mention the float needle valve could be stuck, or making sure they are open when I pump fuel through them.

I've attached a schematic breakdown of my carb and I cannot identify the carb drain plug and float valve. Can you point them out for me (part no.)?

http://www.boats.net/parts/search/M.../0E000001 THRU 0E138599/CARBURETOR/parts.html

Thanks,
E

 

[cgast123]

Re: 1993 70 HP won't turn over

I definantly wouldn't rule out fuel but its possible you could be having a spark problem as well, but seeing how you had troubles getting it started the last time you took it out I would be more on the lines of clogged up carbs or a clogged fuel filter somewhere in that area. Its not a bad idea to do a compression test and a spark test first simply because they are easy to do and don't cost you any money as long as you have the tools, and then you don't waste your time tearing carbs apart and putting them back on just to find out you are working on a engine that needs rebuilt.

 

[ericlindy42]

Re: 1993 70 HP won't turn over

I definantly wouldn't rule out fuel but its possible you could be having a spark problem as well, but seeing how you had troubles getting it started the last time you took it out I would be more on the lines of clogged up carbs or a clogged fuel filter somewhere in that area. Its not a bad idea to do a compression test and a spark test first simply because they are easy to do and don't cost you any money as long as you have the tools, and then you don't waste your time tearing carbs apart and putting them back on just to find out you are working on a engine that needs rebuilt.

Yeah, I am planning to do this in the spring. I actually do not have the tools and was planning to get a cheap compression guage from Harbor Freight. I certainly hope I wouldn't have to rebuild the engine.

You mentioned a fuel filter, I haven't changed it and will try that. It's been about two years since I've changed it. Currently I have the cheap plastic one on there.

Thanks,
Eric

 

[pnwboat]

Re: 1993 70 HP won't turn over

It's should be pretty easy to determine what your problem is. Like suggested, do a compression test. This will tell you what condition the rings and cylinders are in. Second, determine if you're getting any spark. A cheap spark tester from HF or any auto store is fine. You should have a good blue spark that "snaps". Both of those tests are easy and quick to do. If they check out OK, then I would look at the fuel system.

 

[ericlindy42]

Re: 1993 70 HP won't turn over

Hey guys,

So, I went over to the boat this past weekend to fiddle around with it. I did a compression test and got even readings for all 3 cylinders at 95 psi. Next up was checking the spark. I did not get spark for all 3 cylinders. I tested the coils with multimeter and was not getting any voltage at the coils, checked the black and yellow wire lead off the switch box, was getting low voltage. I think the switchbox is fried. Any ideas on what else I could check before shelling out $400 for a switchbox? Also, the motor I have is a "made by mercury" series and I talked to a mechanic, he informed me that I can use a mercury switchbox part. Is that true?

Let me know what you think.

Thanks, Eric

 

[pnwboat]

Re: 1993 70 HP won't turn over

You should check the resistance of the stator. Here is a chart that has the specs.

http://www.cdielectronics.com/downloads/Force_DVA.pdf

 

[ericlindy42]

Re: 1993 70 HP won't turn over

It's been a while since I was able to play around with the engine again. The last time I worked on it was in February, then we had a little baby boy. Been busy since, so I was able to get out this morning and check some things again. Any help would be appreciated. I know i'm pulling up an old thread, hope that's not a problem....

Just to get some general information out. The engine is a 93 Force with mercury designed ignition. I checked the following today:
1) Disconnected black/yellow stop wire at switch box - restarted - nothing. No spark.
2) Disconnected the yellow wire from starter to rectifier - restarted - nothing. No spark.
3) checked the cranking speed and got about 350 rpm. - I can rule out the starter since it cranks enough right????
4) Inspected engine and ignition ground connections - look good. Clean.

Here's where I think the rest of my testing was ineffective since my multimeter wasn't giving me the correct ohm readings for resistance. The attached link is the multimeter i used. http://www.harborfreight.com/7-function-digital-multimeter-90899.html

I had the black meter in the lower port and the red meter in the middle port and used the 2000 ohm dial setting in the lower left corner of the dial. I tested the starter and trigger and got either 0 or 1. obviously something is not right. Can someone tell me what the correct ports and setting on this meter I should be using to test resistance on the starter or trigger? Or, if this multimeter will not do the job?

I tested the switch box and know I was using the correct setting, I got under 2 volts. So the culprit could be the switch box, however, I?m reluctant to spend $300 on a new switchbox if it could be the trigger or starter.

Conclusion:
Could be the switch box ? confident with my test.
Could be the trigger ? not confident.
Could be the starter ? not confident but wondering if it?s fine since it had a good cranking speed?

Let me know what you think.

Thanks

 

[ericlindy42]

Re: 1993 70 HP won't turn over

The other thing I forgot to add was that I tested the battery before cranking and got a reading of 12 volts. Then while cranking it I got 10 volts. Could this mean anything?

Thanks

 

[ericlindy42]

Re: 1993 70 HP won't turn over

Okay,

So I figured out how to get the proper setting on the multimeter. I'm ready to check the ohm resistance to rule out the stator or trigger.

I'm really good at following directions. If someone can just help me clarify the following table and what i'm supposed to connect the black and red multimeter leads to? I know what specifications I should be getting based on the table, however, when testing low speed it says "read" blue to engine ground and I should get 3250 - 3650. Does the black meter lead connect to ground and the red meter lead connect to the blue wire disconnected at the switch box? Also my multimeter only goes up to 2000K ohm setting will this still work if i need to get 3250 - 3650?

http://www.cdielectronics.com/downloads/Force_DVA.pdf

I am at the 70 hp (93 - 95) row. I do not have CDI parts therefore I'm using the numbers that are not "*"

When peforming the readings for the Startor:
Blue to Engine Ground I should get 3250 - 3650
Red to Engine Ground 75 - 90

When performing the readings for the Trigger:
White/Black to Brown, White, and Purple800-1400

Thank you!

 

[WaveJumpingMaxum]

Re: 1993 70 HP won't turn over

20k = 20000 , 200k= 200000, 2000k=2000000 like money. Way battery voltage drops it sounds like you only have a surface charge on the battery so its prob not even enough to spin the starter quick enough have you tried charging it up over night?

 

[ericlindy42]

Re: 1993 70 HP won't turn over

Ahh. Thanks for the conversion. I don't know why I didn't think of that...

The battery is good and has been charged. The starter is spinning the flywheel at 350 rpms. I believe this is plenty to crank the engine.

I also tried to connect jumper cables between my truck battery and boat battery. This didn't do anything.

Can you tell me what color meter leads I should connect to on the wires? Is my thought process right?

Thanks,
E

 

[WaveJumpingMaxum]

Re: 1993 70 HP won't turn over

ok discard surface charge battery 10volts or more while cranking is ok.starter im not 100% on so ill let someone else chyme in or hit you back later when i am 100% but heres what i "know" Red wire off multi meter - Red stator wire Black wire off multimeter - engine ground. for the stator at least. igniton coils you test on the positive with red multimeter wire and negative of the ignition coil to black multimeter wire. on a switch box black wire from multimeter to engine ground , red wire from multimeter to black/yellow wire off switch box. low speed coil charge would be disconect the red and blue wire from the switch box and connect ohm meter inbetween them. high speed coil charge is red wire off stator to good engine ground. switch box bias test you set meter to 20DCV scale, red wire off multimeter to engine ground, black wire to white/black common wire off the switch box. dont quote me on this but starters minimum spinning i belive is 300 rpm for that engine so it should be good. sounds like cdi.

 

[ericlindy42]

Re: 1993 70 HP won't turn over

Back to work on the boat, over the weekend I put in a brand new CDI switchbox. That didn't work, I am able to get a LITTLE spark. When I take the spark plugs out and hold it about 1/8" to a contact surface it will spark, but it's a small orange spark. I am supposed to be able to jump a clean 1/4" gap and it should be blue. So, obviously I am still not getting enough spark.

I took the fly wheel off to check for loose magnets. The magnets look brandnew and are all intact. I checked the stator and trigger, they look good, clean. I checked the voltage on the stator and it seems fine, however, I keep having issues with the resistance and it was reading 0, so I assume there is no resistance which there should be. Am I right on this? Sounds like the stator is shot. I'm thinking, it was a b*&th to take that flywheel off, so I'm just gonna put in a new stator and trigger. Any thoughts?

Thanks,
Eric

 

[ericlindy42]

Re: 1993 70 HP won't turn over

Can someone please chime in?

I am down to either the Stator or Trigger. Replaced the switch box, still not getting a clean blue spark. I can only get a small orange spark about 1/8". Engine still will not fire. Could it be anything else?

Thanks,
Eric