crank no start

[waterlogged74]

Hello all, new to the boating world here. I picked up a 1974 reinell with a mercruiser 888 ford 302 in it. Since I bought it I haven't been able to get it to start. the engine will crank over, but will not start. In troubleshooting, I've discovered no spark from the high tension lead of the coil. I've replaced the coil, still no spark. From reading other posts, I've checked voltage at coil: 12.38v, disconnected the tach wire, cleaned connections at starter and battery and all other connections I could see, checked the timing from no. 1 at tdc although timing wouldn't have any affect if I can't get power to the dist., all to no avail. I've been known to be slightly mech inclined, but this is driving me absolutely nuts. any suggestions on what I should look for will be appreciated.

 

[Don S]

Re: crank no start

I've replaced the coil, still no spark.

That's what every newbie does and finds it still doesn't have spark.

Tune it up with a new set of points and condenser, set them properly with a dwell meter, and you will have spark again.

 

[waterlogged74]

Re: crank no start

Don, I appreciate the fast response. From what I've read in the other threads your opinions and suggestions are to be respected. Just for my own clarification, with no spark coming from the coil, would anything going on in the distributor make a difference?

 

[Don S]

Re: crank no start

The points and condenser are in the distributor and is what causes the coil to spark.

 

[waterlogged74]

Re: crank no start

Thank you for clearing that up for me, I've got more things to check out now. will report back with any findings.

 

[Don S]

Re: crank no start

Have a look at this thread before you start looking at things, http://forums.iboats.com/showthread.php?t=329742&p=2186518#post2186518

Also download the OEM service manual for your engine here http://www.4shared.com/office/mRjamBOE/03__Engines__All__78-84.html?
I think you are going to need it.

 

[stonyloam]

Re: crank no start

You seem to misunderstand how the coil and points work together. A coil is a transformer with two sets of windings in it. A primary with few windings and a secondary with many windings. When your points close (assuming good contact) 12V flows through the primary to ground. This sets up a strong magnetic field. When the points open the current stops and the magnetic field collapses and because the secondary has many more windings the voltage is stepped up to 20,000 v or more and that voltage is applied to the wire coming out of the top of the coil, to the distributor, where the rotor directs it to the proper spark plug wire at the correct "time". So if your points are not making contact then you will get no current flow through the coil, even though you have 12V on the +.

 

[waterlogged74]

Re: crank no start

replaced condenser, points look good( clean, good alignment, proper gap) and I do have an oem service manual that came with boat. still nothing. the tach doesn't register rpm's while cranking, however I get no results with it disconnected either.

 

[Don S]

Re: crank no start

replaced condenser, points look good

Looked good ?????? :facepalm:

 

[Bt Doctur]

Re: crank no start

the glazed over look i guess still looks good.

 

[waterlogged74]

Re: crank no start

when I say looked good I mean they aren't burned, pitted, glazed, or any other undesirable condition. I went ahead and hit them with a file anyway though, but that still left me with nothing. I am familiar with ford engines in an automotive setting, that's why I figured I could get this thing running in the first place. I was just hoping that the marine version had some variation that I'm not seeing that would create a no start situation.

 

[Bt Doctur]

Re: crank no start

1 power to the coil
2 check wire from -coil to dist for ground.
3 points must make contact opening and closing ,a test light makes a good tool with the wire lead hooked to +12v and the probe tip to the
wire on the - side of the coil.light wiil flash is rotor is turning and the points are making contact thru the wire going to the coil.
4 bad wire from tower to cap

 

[jeffssgtusmc]

Re: crank no start

I think u can get a electronic ign conversion kit for that. I got one for my 350 and it ran great.

 

[jeffssgtusmc]

Re: crank no start

Look at hotspark.com