Replacing distributor/coil... a few questions.

CoreyK · **Joined:** Thu Apr 12, 2012 10:26 pm **Posts:** 5

So I started up my recently purchased '93 Four Winns (carb'd 5.0 OMC Cobra I/O (Ford 302)) for the first time today after replacing the plugs, wires, distributor cap and rotor (as well as changed the motor oil and gear lube), and it sounds to me like it's still missing when I give it some throttle.

I opened up the distributor and this is what I saw:

Now I haven't had much experience with distributors, but that I think is an old, nasty looking distributor that has seen better days... and a crappy Accel ignition coil.

So I think it's time to get a new distributor and coil all together.

In doing some research I've found that it seems OEM distributors for this model engine are unavailable ("obsolete" on parts websites), so my only options are aftermarket. I can either go electronic (~$375 in all) or old-school points (~$300 in all).
I'm definitely leaning towards electronic; in particular, this distributor/coil:
http://www.aaamarine.com/servlet/the...rtronix/Detail

and the necessary module for use with an OMC drive:
http://www.aaamarine.com/servlet/the...se-with/Detail

These products should cover all my bases and be completely plug and play.

Two questions:
1) Will this electronic distributor maintain any sort of timing alteration like the stock distributor?
2) Will upgrading to this electronic distributor make setting the timing more complicated/difficult? I was planning on having a mechanic do that, as I've never done anything timing related before, and don't really trust myself;
I just don't want for a mechanic to be unable to set the timing correctly (or turn away my business entirely) due to having aftermarket parts.

Any thoughts are appreciated.

Winter Sux · **Posted:** Sat Apr 14, 2012 7:40 pm

Just a tip prior to throwing hundreds at it. Have your missfire diagnosed.

ric · **Posted:** Sat Apr 14, 2012 8:27 pm

Its a 351 Windsor, you could put any ignition and anyone could tune it.

fiznuka · **Posted:** Sat Apr 14, 2012 8:32 pm

The drive shaft for the oil pump between the 302 and the 351 are different sizes so make sure you get one for the 302

CoreyK · **Joined:** Thu Apr 12, 2012 10:26 pm **Posts:** 5

Thanks for the replies everyone.

So after doing some research, I figured out that the distributor is actually OEM; apparently around 1993 they began switching over to "point-less" electronic units.

I've also discovered that the ignition coil on there is not a marine coil but rather a universal automotive coil, so I've ordered a new OEM coil and wire, as well as a new fuel filter. I'm thinking it's possible that the automotive coil may have started to go since it was not designed for a marine application...
If replacing these still doesn't fix the problem, I'm going to take it into a shop to have the misfire diagnosed; if it is the distributor, I'm going to see if they can salvage my existing one, and if they can't I will try to get an aftermarket replacement as the OEM distributor is no longer available.

However, I was wondering... I was able to find a Mallory marine distributor for the Ford 302, but it is a points style distributor, while this boat came with an electronic "point-less" setup. Would a points-style distributor be plug and play since the boat is set up for a point-less distributor? Would I have to change the module etc.?
Anyone know of a direct OEM replacement distributor for this motor?

Thanks!

ric · **Posted:** Sun Apr 15, 2012 10:34 am

Pointless is 110x better. There is no such thing as a marine coil. All coils are sealed units. You need to change the points and condenser in a points style ign every tune up.

That pertronix is perfect. Very easy to install, minutes literally. Once installed just get a timing light to verify its position and your set.

The timing advance is done by springs. With a timing light you rev it to certain rpm and verify its advance degrees according to the factory specs. If not right, change springs. Personally id run it a few degrees advanced over factory specs. It will run better on modern gas.

LouC · **Posted:** Sun Apr 15, 2012 7:14 pm

If the boat was set up with an electronic distributor, the ESA module would have to match this, in that the ESA has to work with the ignition system you have on the engine, to lower the idle speed so that when you shift to neutral, the drive can come out of gear. Outdrives that use dog clutch shifting like the older Cobras (86-93) and all Merc Alphas have to use a shift interrupt system to lower the idle speed to allow the load on the clutch dogs to release and then the drive will go into neutral when you move the shift lever. If this system is not working you will have trouble shifting from in-gear to neutral on the water because the load of the water against the prop makes it harder for the clutch dogs to release. Volvos with cone clutch shifting and late model Cobras (94-98) also do not use an ESA system.

Many have used a Delco EST Marine electronic distributor to up grade older OMC ignition systems, it can be made to work with the ESA with the right module. There is information over on the OMC forum at http://www.iboats.com

If you wanted to use a points distributor, the ESA module would have to match it. I have a points system and since I grew up with them in cars it's no issue for me to deal with and I still use the OE distributor. But if this one wore out I'd get the Delco EST.

I would not advance your timing over OE specs, because you don't know certain things that will affect engine durability. One thing is carbon build up, if you have a lot of it and cold running marine engines often do, then it will increase the octane requirement of the engine and make it more likely to ping and detonate. Advancing the timing may cause serious damage in that case. The other thing is a too lean fuel mixture. Start with getting the distributor and coil set up right, and set it to OE specs and see how it runs. It's always a good idea to do a compression test because it will tell you the general health of the engine and also if you do have a lot of carbon build up (higher than normal compression readings). It is also good to learn how to read spark plugs because that will tell you if your mixture is right....

Jesse · **Joined:** Sat Feb 25, 2012 6:19 pm **Posts:** 17

If I were to replace my distributor in my 5.8 would go with an HEI from DUI. They engineer the reliable and performance of the GM HEI onto abillet housing to fit almost any motor. i think you are looking at 3something but all you need is a key on hot wire. They do make a Ford Marine dist.

www.iFourWinns.com

Replacing distributor/coil... a few questions.

Who is online