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CBRENT
06-27-2012, 10:23 AM
1986, 351W
Recent updates (all within the past 2 weeks):
Rebuilt carb, new PerTronix distributor and PerTronix Ignitor II, fuel line to carb.

Boat starts right up, cold. Runs like a champ in all scenarios, idling, cruising, pulling skiers, everything... roughly around an hour into the outing the boat starts to hesitate when taking off and then just dies, like I turned it off. Then I can start it with some slight pumping of the throttle but it will not stay running in neutral, it will stay running if revving or lever is slightly in the reverse position. As soon as I move lever to neutral position it dies, no sputter, just dies.


This has happened on 2 occasions since the updates to the motor.
Most recently this morning, after a full session of skiing.

Any insight would be most appreciated!

Thanks.

thatsmrmastercraft
06-27-2012, 10:40 AM
I thought they only made Gremlins from 1970 - 1978???

Seriously though, need to figure out the source. Next time it dies like this, pop open the engine cover, remove the flame arrestor and look down the throat of the carb. Is it full of gas or dry as a bone?

Next, have someone work the throttle (without cranking the engine) to see if there is any gas left in the carb. Work the throttle a number of times as there will be some fuel in the accelerator pump diaphragm.

Next crank the engine and carefully look down the carb (of course don't put your face directly over the carb) and see if there is any fuel present. If you have no fuel look at float adjustments, fuel pump (volume test), fuel filters, metal fuel line (is it tight), rubber fuel line from tank to pump(is is breaking down internally). It may be more than one problem.

If you have fuel present you need to move to the ignition side. Simple spark test is with a timing light and look for the light to flash.

This is all assuming you have fresh spark plugs, dist cap & rotor, spark plug wires...

You should take a look at the spark plugs to see what color you see. This will give you an indication of how rich/lean the engine is running.

CBRENT
06-27-2012, 10:54 AM
@ thatsmrmastercraft

Thanks for the suggestions! Seems weird that any and all of these things you mentioned would only happen after a said period of time. I figured these things would be a problem from the get go, not an hour or so later, but this is why I'm posting this.

I'll look at the plugs tonight. stay tuned.

Nice pic!

tex599
06-27-2012, 12:40 PM
Sounds like your carb is still clogged somewhere. Did you soak the metering plates and blow out all the holes? What about the main fuel filter, has it been changed recently?

CBRENT
06-27-2012, 01:53 PM
@ tex599

Thanks.

The main fuel filter has not been changed, to honest it might have not ever been changed as far as I know. Is that an easy thing I can tackle? Not even sure where it is, haha.

Lumbergh
06-27-2012, 02:07 PM
Change the fuel filter (its just an auto Ford 351W fuel filter - NAPA part # 3943 or #39413) and fuel - water separator (Racor 110 I think).

Trace the fuel line down from carb to find both filters.

Fuel line (skidim) is still showing as skidim's 2nd top seller in their top 10, maybe for a reason...

thatsmrmastercraft
06-27-2012, 02:09 PM
@ tex599

Thanks.

The main fuel filter has not been changed, to honest it might have not ever been changed as far as I know. Is that an easy thing I can tackle? Not even sure where it is, haha.

This may be the weak link.

When something takes an hour to occur, it is often times a particular set of circumstances that cause the problem. It may be a long run or a heavy load which the combination of a float set a little too low and a partially clogged fuel filter allows the carb to run dry, where just one or the other won't allow that to happen to the point of fuel starvation.

oxberger
06-27-2012, 02:10 PM
Ditto for what Lumbergh said. My first thought was the fuel filters. How old is the fuel you are using and how long had it been in the tank?

CBRENT
06-27-2012, 02:25 PM
@oxberger

Boat has been in the water for couple months now. We've ran through several tanks of gas at this point. This is a recent issue only after updating the pieces in the first post.

Thanks.

CBRENT
07-16-2012, 01:32 PM
Sorry I'm just now updating this, finally swapped out the fuel filter. Pretty easy job, it's just not the best location. Kinda awkward to get to. Everything looked good when I opened the canister. The filter looked good, little discolored but I think that's just because it was wet. There was a tiny bit of sediment in the bottom of the canister. Put new filter in and buttoned her back up. Filled the tank with fresh gas and added a bottle of sea foam, just incase there was a water issue. Drove like a charm, no issues.

Forward a week later, prolly half tank of gas later, after about an hour on the water, it dies. So now I'm back where I started... haha.

I'm now wondering if there is something wrong inside the tank?

Thanks for the initial input oxberger, thatsmrmastercraft, tex599 and Lumbergh!

j.mccreight@hotmail.com
07-16-2012, 02:53 PM
Sorry I'm just now updating this, finally swapped out the fuel filter. Pretty easy job, it's just not the best location. Kinda awkward to get to. Everything looked good when I opened the canister. The filter looked good, little discolored but I think that's just because it was wet. There was a tiny bit of sediment in the bottom of the canister. Put new filter in and buttoned her back up. Filled the tank with fresh gas and added a bottle of sea foam, just incase there was a water issue. Drove like a charm, no issues.

Forward a week later, prolly half tank of gas later, after about an hour on the water, it dies. So now I'm back where I started... haha.

I'm now wondering if there is something wrong inside the tank?

Thanks for the initial input oxberger, thatsmrmastercraft, tex599 and Lumbergh!

Check your anti siphon valve on top on tank,
Did you reuse the original distributor and just added an electronic ignition conversion? Flame thrower II coil is not compatible with the ignitor I ignition kit. If these are your parts this may be your problem the coil is cooking your ei.

CBRENT
07-16-2012, 03:00 PM
@j.mccreight: I installed a new PerTronix distributor. Anti-siphon valve, sounds interesting. What would I be looking for? I'm assuming it's a mechanical part that goes bad. thanks.

hairlesshacker
07-16-2012, 05:20 PM
If it only happens after you've been running for an hour, I would suspect the coil. There are many stories of them getting hot after some time and then giving people trouble after switching to EI, either because it's the wrong coil for the EI setup, or the ballast resistor is not used when needed. (I'm not saying pertronix does or doesn't need it, I don't recall which kit uses which...)

thatsmrmastercraft
07-16-2012, 05:34 PM
No ballast resistor needed for an Ignitor II electronic ignition. I used PerTronix 45011 Flame-Thrower II 45,000 Volt 0.6 ohm Coil.

CBRENT
07-16-2012, 07:29 PM
This is my set up:

Distributor:
http://www.shopatron.com/products/productdetail/part_number=D231801/591.0?utm_source=591.0&utm_medium=email&utm_campaign=ShipmentTrackingEmail

Coil:
http://www.skidim.com/prodinfo.asp?number=PNX45-111

No resistor.

thatsmrmastercraft
07-16-2012, 10:47 PM
This is my set up:

Distributor:
http://www.shopatron.com/products/productdetail/part_number=D231801/591.0?utm_source=591.0&utm_medium=email&utm_campaign=ShipmentTrackingEmail

Coil:
http://www.skidim.com/prodinfo.asp?number=PNX45-111

No resistor.

Nice :cool:

j.mccreight@hotmail.com
07-17-2012, 12:03 AM
@j.mccreight: I installed a new PerTronix distributor. Anti-siphon valve, sounds interesting. What would I be looking for? I'm assuming it's a mechanical part that goes bad. thanks.

valve is located on fuel tank, check for gunk and restrictions...

CBRENT
07-17-2012, 09:10 AM
@thatsmrmastercraft: thanks man. The distributor is really sweet looking, nice craftsmanship.
Wasn't trying to brag, it was more for making sure it was the correct set up.

@j.mccreight: thanks for the info, I'm planning on looking into it this weekend.

thatsmrmastercraft
07-17-2012, 10:06 AM
@thatsmrmastercraft: thanks man. The distributor is really sweet looking, nice craftsmanship.
Wasn't trying to brag, it was more for making sure it was the correct set up.

@j.mccreight: thanks for the info, I'm planning on looking into it this weekend.

No worries. Ignitor II and 0.6 ohm Flamethrower coil is perfect.