need help! no spark mercruiser 140

jcstu

Cadet
Joined
Jun 8, 2011
Messages
8
Hello,
I have a 1984Chapparal with a Mercruiser i/o 140 with the alpha 1 drive. It has been in storage for a couple years and hasn't been started. I am attempting to resurrect the motor and possibly restore this boat. I don't seem to be getting spark. I have went through the trouble shooting tutorial that I found on this forum but still have no spark. I found some wire going to the trim tab that were rotted. I have disconnected these wires from the circuit panel on the back of the engine. Would these wires have any relevance over the engine not starting? I know they will need to be replaced before I can use the boat, however I would like to get it started before spending the time trying to re-run the wires throught the transom. Any help would be greatly appreciated.
 

jcstu

Cadet
Joined
Jun 8, 2011
Messages
8
Re: need help! no spark mercruiser 140

Oh, just a couple more details of what I have done so far. I replaced the coil. I am getting about 7.5 volts to the postitive side of the coil. I have checked for spark in the coil tower as well as the plug wires, no luck either place. The troubleshooting tutorial I used was http://forums.iboats.com/showthread.php?t=335407&pagenumber=.
 

Reming870

Petty Officer 2nd Class
Joined
Jul 15, 2010
Messages
191
Re: need help! no spark mercruiser 140

Are you convinced there is no spark? If the boat has been sitting for a long period it may not be getting fuel to the pump.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: need help! no spark mercruiser 140

Put in some new points and condenser. The points are a tuneup item, and they are probably glazed over from sitting.
 

jcstu

Cadet
Joined
Jun 8, 2011
Messages
8
Re: need help! no spark mercruiser 140

I have used a spark tester at the coil and between the distributor and the plugs. Since I couldn't get a spark at the coil, I thought the problem might be before the distributor. I will try new points and condenser. I tried to clean the old ones, but I'm sure they need replaced anyway. I'm pretty sure the fuel is getting through as I pulled a plug and it was wet. I also tried fresh gas and starter fluid directly into the carb (this has worked in the past but not this time). Any thoughts on the wiring for the trim tab causing an issue? thanks Josh
 

RogersJetboat454

Commander
Joined
Jul 9, 2010
Messages
2,964
Re: need help! no spark mercruiser 140

Since I couldn't get a spark at the coil, I thought the problem might be before the distributor. I will try new points and condenser. Any thoughts on the wiring for the trim tab causing an issue?

The points and condenser control the negative voltage fed to the coil, and are housed inside the distributor. Do you have an OEM service manual for this engine? Having one will help you set up the new points.

Don't see how the trim tabs should be a concern, unless someone tied the wiring for them into the primary ignition circuit :confused:
 

jcstu

Cadet
Joined
Jun 8, 2011
Messages
8
Re: need help! no spark mercruiser 140

Unfortunately all I have is a generic owners manual that is no help. I did find information about setting up the points, so i should be good there. I probably need to find a manual for this engine, especially if I decide to go forward with a complete restore on my boat. Any suggestions on where to get or download one?
 

RogersJetboat454

Commander
Joined
Jul 9, 2010
Messages
2,964
Re: need help! no spark mercruiser 140

Unfortunately all I have is a generic owners manual that is no help. I did find information about setting up the points, so i should be good there. I probably need to find a manual for this engine, especially if I decide to go forward with a complete restore on my boat. Any suggestions on where to get or download one?

Take a look at this;
http://www.4shared.com/document/D-qIfFRU/Mercruiser_Service_Manual_10_1.htm

Says '85-'89, but may cover what you're seeing too.
 

jcstu

Cadet
Joined
Jun 8, 2011
Messages
8
Re: need help! no spark mercruiser 140

Thanks,
on my way to pick up a tune up kit. Will let you know how it goes.:)
 

81 Checkmate

Lieutenant
Joined
Jul 20, 2010
Messages
1,360
Re: need help! no spark mercruiser 140

Where abouts you located in Cincy? I may be able to help you out a time or too in my spare time.

Good Luck on your project!
 

jcstu

Cadet
Joined
Jun 8, 2011
Messages
8
Re: need help! no spark mercruiser 140

I'm on the west side. I have now achieved spark! Next step i guess will be draining the fuel and starting with fresh. She tries to fire now but even with putting fresh gas in the carb it just puffs smoke at me.
 

searay3

Senior Chief Petty Officer
Joined
Apr 7, 2005
Messages
655
Re: need help! no spark mercruiser 140

get your timing light hooked up and your dwell meter. Check the dwell while cranking. Loosen the distrib hold down bolt and turn the distrib a little one direction or the other until it starts. Make sure the firing order is correct, plug wires in good shape...
 

jcstu

Cadet
Joined
Jun 8, 2011
Messages
8
Re: need help! no spark mercruiser 140

Thanks for everyones help. I have company coming this evening and won't get to work on the boat again until after the weekend. I will update after that. I'm sure I will have more questions. :)
 

smoothee

Recruit
Joined
Jun 16, 2011
Messages
1
Re: i have a 4.3 i have put newer motor in . i can get the motor to turn over but no

Re: i have a 4.3 i have put newer motor in . i can get the motor to turn over but no

need help on my 4.3 92 cranks but wont start
 

RogersJetboat454

Commander
Joined
Jul 9, 2010
Messages
2,964
Re: i have a 4.3 i have put newer motor in . i can get the motor to turn over but no

Re: i have a 4.3 i have put newer motor in . i can get the motor to turn over but no

need help on my 4.3 92 cranks but wont start

Welcome to Iboats.

I recommend starting your own thread rather than hijacking someone else's. When you do, please include more information about your make, model, and serial number of your engine. To start off with, take a look at the adults only section here; http://forums.iboats.com/showthread.php?t=288430. It will help you out with figuring out whats wrong with your engine. ;)
 
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