She runs great then dies

Sounds like the same issue I have every year. The fuel screen on the inlet of the carburetor gets all blocked up with crap that's sucked up from the fuel tank. I have to remove and clean the screen every year. I suffer the same symptoms as you described. Good luck and keep us posted. Ken

As to why PCM/ CC used 350's in some models as an option back then, I couldn't tell you. Well, other than that the fords ARE better;) The SBC's are definitely less popular in these years, and most years up until the early 2000's, and of course 2003 when there were no more 351w powered CC's.

HOOOAH Thanks, I will switch out the dis when I get home for leave and put the correct marine one on so we dont blow the engine cover off and kill some one. I can still asure you that the centrifical weights are spot welded togethor. When I change out the unit which still runs awsome but not safe, I will take a few pics and post them in about three weeks for you mechanic guys that are confused on how it does not work! Hell I might be confused

Thanks for the advice.

I will purchase the MSD 822 epoxy and ballast resistor and exchange them before i go out next, all we want to do is top keep the boat running, it became such a pain last year to spend 4 hours out of your day to be dissapointed every time we got in the boat and have to be towed home. I will let you know how we get on.

TRBenj wrote: 84SN2001 wrote: Pete, The HEI is an automotive ACCEL distributer. As we all know that the engine is reverse rotation so the gears on the automotive dis were backwards as automotive engines are regular rotation, luckly the dis gear from the Malory was an exact fit on to the ACCEL dis. The guy that helped me do the work, told me that all the marine dis that he's ever seen never had an advance with centrifical weights-IE mercruiser , so he just tac welded them togethor to make the timing advance obsalete.        long story short we just changed the gear on the dis and tac welded the centrifical weights togethor and the thing fires a spark so strong you could power a house!! ;)   "not really"       Hopefully all that made sence and sorry for any incorrect spelling as I am in the Infantry all we know how to do is pull the triger and kill the enemy!!! Will be home on leave in three weeks from S. Korea so show you pics in detail of the Beautiful all orginal '84 SN 2001 I have a feeling Pete was baiting you with his question. What your mechanic told you is incorrect on many different levels. Locking the timing in will likely either cause the boat to start/idle poorly or run poorly up top- or possibly both. Marine distributors still use the mechanical advance (weights and springs) mechanism, what they dont have is a vaccuum advance, since boat engines are always under load. Also, an automotive distributor is a major safety hazard on a boat (and a violation of USCG regulations), as it is not spark arrested like a marine unit. Just a few gas fumes in the bilge and you have a recipe for disaster. I would strongly consider ditching the HEI you have on there now, in the name of safety. Performance Distributors sells a marine HEI unit if you want to stick with that type of ignition system.

Tim,
I don't understand what you're implying?
Brian,
To a certain extent, Tim is correct but I really was confused about your mechanic welding the weights together. Every engine needs a means of advancing the sparks as RPM's increase. I'm still confused but it must be a misinterpretation from your mechanic.

Tim is absolutely correct that not running a marine rated component is unsafe. Take a look at getting it swapped out.

Pete, The HEI is an automotive ACCEL distributer. As we all know that the engine is reverse rotation so the gears on the automotive dis were backwards as automotive engines are regular rotation, luckly the dis gear from the Malory was an exact fit on to the ACCEL dis. The guy that helped me do the work, told me that all the marine dis that he's ever seen never had an advance with centrifical weights-IE mercruiser , so he just tac welded them togethor to make the timing advance obsalete.        long story short we just changed the gear on the dis and tac welded the centrifical weights togethor and the thing fires a spark so strong you could power a house!! ;)   "not really"       Hopefully all that made sence and sorry for any incorrect spelling as I am in the Infantry all we know how to do is pull the triger and kill the enemy!!! Will be home on leave in three weeks from S. Korea so show you pics in detail of the Beautiful all orginal '84 SN 2001

I have the set up you describe above gun-driver with the white balast resistor underneath the red cut off switch with the purple wire going to the coil

Yours is showing the same symptoms as mine did when I was trying to get the elec conversion to work. It ended up overheating the coil.
Since the PO did a lot of mickey mouse things to it.
I'm wondering if he bypassed the ballast resistor which would cause your symptoms.

At the back of the motor under the plastic cover with the red breaker button. See if you have one of these installed. And check if you have a red wire in and the purple out to the + side of the coil.

This tool was mentioned recently in cycleworld. They're pretty cool. They can help diagnose anything with spark ignition. You don't need any tools to put it on, and it can be left in place with the engine running. I've seen them used on the automotive side as well, I don't see why you couldn't use one with a boat.

Put it on and start your boat, and watch the light go on. When your boat goes into it's dead mode, see if it's still lighting up when you crank the engine over. No light, then no spark. Then all you have to do is figure out why you're not getting spark, coil etc.:

84SN2001 wrote: Swith to HEI with new plug wires and plugs!!! Get rid of the coil and old distributer. I had the same problem, the pick up in the distributer cap was bad so I switched the whole ignition system, the 350 cranks right up every time now with no problems. The only thing you will have to do is weld the counter weights togethor because their is no vacume advance on the marine carb!!! I think I said that right

Brian,
I'm trying to get a better picture of your HEI conversion. What did you do with welding advance counterweights?

Swith to HEI with new plug wires and plugs!!! Get rid of the coil and old distributer. I had the same problem, the pick up in the distributer cap was bad so I switched the whole ignition system, the 350 cranks right up every time now with no problems. The only thing you will have to do is weld the counter weights togethor because their is no vacume advance on the marine carb!!! I think I said that right

i have found how to add picture but mine are to big. Hold on while i find a way to shrink them

Here are some pics that might help you out.

First I guess the easiest way to figure out if you have points or elec. conversion is, does it have one or two wires coming out of the distributor?

If it has points it should look like this under your cap.


Or does it have something like this under the cap.


Next here are all the parts numbers for cap, coil, rotor and points for your boat. They are "Standard" brand and can be found at most auto parts stores for half of what you would pay at a dealer or West Marine.

Posting some pics will allow us to determine if the parts are marine or not.

The way you describe it, it seems like the problem is coil/ ignition related.

If the boat runs perfectly for as long as you mention, then dies, that does sound like the coil is getting hot and either not the proper resistance, or maybe the ballast resistor is not hooked up anymore.

Also, the distributor cap needs to be down tight. If the side that has the stripped screw is making that side sit up and not tight like it's supposed to be, then that could be a problem, but the fact that it's running well for a while makes me think that isn't the root of the boat cutting out. You might be able to retap that distributor and use an oversized screw in it.

West marine might have the proper cap for it, actually I would think they would as these motors were used in a ton of marine apps. Pretty much because it is a different distributor, an automotive one won't typically work on a marine distributor, not on a ford 351/302 motor at least.

The elbow going into your manifold was probably plastic for both sides. My 78 has the originalbrass ones later, but either will work, as long as they are not crack plastic elbows and they are in good shape. I know CC/ PCM switched to brass ones later.
   

It would help us if you could post some photos. Do you have a CC dealer near you ? the cap needs to be marine.