351W no start when warm - ignition issue?

[Slide]

The saga continues! I think I am unearthing pre-existing issues with my 93 PS205, 351W. This offseason I installed a bunch of new parts: Edelbrock 2181 manifold, Quickfuel M600 carb, fuel pump, circ pump, raw water pump, Db electrical 105A alternator. The boat runs great initially - fires right up, pulls hard to WOT. However, it starts misbehaving after it's hot - say, after pulling skiers around for 30-40 mins.

First symptoms are loss of power and chugging when taking off and rough idle. After shutdown at this point, the boat will not start. It turns over easily and I can't see flooding - there is fuel in the manifold when I open the throttle but it is not dribbling or excessive. So, I believe I have an electrical issue.

I replaced the ignition coil and plug wires with new and inspected all the plugs, then went out and ran it hard for about 20 minutes today. I shut it down and let it heat soak for a bit, and it refused to start through multiple attempts over an hour. I pulled the #5 plug to check for spark, and it was only getting a weak spark every 3rd turn or so. When I had that plug out to check, it finally wanted to fire so I reinstalled the plug and tried to start, but it wouldn't turn over at all. Figured I had killed the battery so I hooked up my jump box, and it started after two turns! Ran OK to get it back on the trailer. I checked the battery voltage with a voltmeter after and it showed full! 12.8 volts. It's a 2.5 year old Exide dual purpose AGM battery.

I also checked the voltage at the ignition coil positive and it's about 10.5 volts running. I think this might be the source of my problems - ignition is not getting enough juice. I believe I need to:
-Replace ignition switch
-Add heftier wiring from ignition switch to wiring harness
-Get a new battery
-Probably replace ignition module / distributor

Any other thoughts? This has been driving me nuts but I'm certain I have some kind of electrical problem. When it's started, the boat runs great.

[Gamble]

I would do the simple and easy things first. I would load test that battery after you completely charge it. If it's bad, replace it and go from there. Do the easy stuff first. A bad battery or one with weak/compromised cells cand wreak havoc........

[Slide]

I'll definitely do the diligence with the battery, but I don't want a good battery to mask the real root cause. Otherwise I'll be doing this again when new battery gets bad.

[samtechwaterski]

I had this problem with my 351W. I ended up replacing the electronic ignition with this module along with the flame thrower coil they recommend. Fixed the problems immediately. No more hot start issues.

https://www.skidim.com/prodinfo.asp?number=PNX-91582

[Slide]

Thanks for the info! I suspect I might end up replacing the module and distributor. Fortunately I have a new Pertonix distributor on my shelf that I was going to install in the spring.

As for the battery, I had it load tested and it was indeed faulty under load. I picked up a new Duracell dual purpose today. I'm going to put in a new ignition switch as well, as I recall testing a pretty significant voltage drop across it.

[88falcon]

Thanks for the info! I suspect I might end up replacing the module and distributor. Fortunately I have a new Pertonix distributor on my shelf that I was going to install in the spring.

As for the battery, I had it load tested and it was indeed faulty under load. I picked up a new Duracell dual purpose today. I'm going to put in a new ignition switch as well, as I recall testing a pretty significant voltage drop across it.

I love my pertronix distributor with the flamethrower coil and electronic ignition combo. You won't regret it

Sent from my SM-G950U using Tapatalk

[Slide]

I love my pertronix distributor with the flamethrower coil and electronic ignition combo. You won't regret it

Sent from my SM-G950U using Tapatalk

I think I'm gonna go ahead and do it. Now I have to learn how to do timing!

[88falcon]

I think I'm gonna go ahead and do it. Now I have to learn how to do timing!

Do you have a timing light?

Sent from my SM-G950U using Tapatalk

[waterlogged882]

I think I'm gonna go ahead and do it. Now I have to learn how to do timing!

Timing is easy. Much easier with two people.

Mark your balancer with tape, nail polish, paint stick, or some easy to see mark (not required).

You are looking for 10 deg BTDC on the balancer scale.

Run it at 600 RPM, hook the light to your battery, put the clamp on the number one cylinder plug wire, and see where the mark hits. You may very well be in timing without any adjustment.

I will say this...if you are installing a new distributor, there are a few steps to address before you move anything. Sure makes life easier if you benchmark a few steps when setting in the new distributor.

.

[Slide]

I decided to tap the brakes a little - I'm going to do the ignition wiring upgrades I mentioned first, and change the cap and rotor before I go after the entire distributor. I will eventually change it but hopefully not until next spring; what are the other steps I should take first?

[waterlogged882]

I decided to tap the brakes a little - I'm going to do the ignition wiring upgrades I mentioned first, and change the cap and rotor before I go after the entire distributor. I will eventually change it but hopefully not until next spring; what are the other steps I should take first?

Orientation of the distributor relative to cylinder and the position of the rotor when #1 cylinder is top dead center. This gives reference to the new distributor for ease of installation. You only get one chance to do this before you start wrenching.

With the new EI module conversion, likely the timing will not change but I like to check anyway.

.

[DKaua'i]

The saga continues! I think I am unearthing pre-existing issues with my 93 PS205, 351W. This offseason I installed a bunch of new parts: Edelbrock 2181 manifold, Quickfuel M600 carb, fuel pump, circ pump, raw water pump, Db electrical 105A alternator. The boat runs great initially - fires right up, pulls hard to WOT. However, it starts misbehaving after it's hot - say, after pulling skiers around for 30-40 mins.

First symptoms are loss of power and chugging when taking off and rough idle. After shutdown at this point, the boat will not start. It turns over easily and I can't see flooding - there is fuel in the manifold when I open the throttle but it is not dribbling or excessive. So, I believe I have an electrical issue.

I replaced the ignition coil and plug wires with new and inspected all the plugs, then went out and ran it hard for about 20 minutes today. I shut it down and let it heat soak for a bit, and it refused to start through multiple attempts over an hour. I pulled the #5 plug to check for spark, and it was only getting a weak spark every 3rd turn or so. When I had that plug out to check, it finally wanted to fire so I reinstalled the plug and tried to start, but it wouldn't turn over at all. Figured I had killed the battery so I hooked up my jump box, and it started after two turns! Ran OK to get it back on the trailer. I checked the battery voltage with a voltmeter after and it showed full! 12.8 volts. It's a 2.5 year old Exide dual purpose AGM battery.

I also checked the voltage at the ignition coil positive and it's about 10.5 volts running. I think this might be the source of my problems - ignition is not getting enough juice. I believe I need to:
-Replace ignition switch
-Add heftier wiring from ignition switch to wiring harness
-Get a new battery
-Probably replace ignition module / distributor

Any other thoughts? This has been driving me nuts but I'm certain I have some kind of electrical problem. When it's started, the boat runs great.

I would check ALL grounds and electrical connections. Take them off and wire brush/clean and check for any hairline cracks, When the engine gets hot everything expands and therefore the cracks get bigger and lose connection (until it cools enough to make solid contact again). re-assemble with plenty of dielectric grease to avoid corrosion. The crack can actually be within a wire so you can't see it. I replaced my 2 gage wire from battery to starter relay and also the wire from relay to starter and it solved my hot starting issue. Also, When you say "after it's HOT".. What is your temp running? I had an overheating issue and was getting temp readings over 200.. Turned out my exhaust hoses were collapsed inside (another thing you can't see until you take hoses off and inspect) therefore the engine wasn't cooling.. just some thoughts ... good luck!!

[Slide]

Appreciate the info! Hot is 143deg - I put a cooler thermostat in it this year. I have changed a LOT of parts on this thing, but I believe this specific issue to be pre-existing as it has issues with bogging under power while hot before I did anything.

I put in a new cap and rotor and a new Duracell dual purpose battery. A friend recommended a brilliant idea - add a relay to get good voltage to the ignition coil. I did so, and have a healthy 12.1 volts at the coil. BUT.... same problems! Boat fires right up when cold, runs strong, but if I cruise around and get it up to temperature then shut it down, it will refuse to restart.

The ONLY other thing I can think of is to replace the ignition module. I think it's a pretty likely cause from what I'm reading. The wires, cap, and rotor are all brand new. The plugs have about 10 hours on them and they all look good.

[d2jp]

I had this problem with my 351W. I ended up replacing the electronic ignition with this module along with the flame thrower coil they recommend. Fixed the problems immediately. No more hot start issues.

https://www.skidim.com/prodinfo.asp?number=PNX-91582

Appreciate the info! Hot is 143deg - I put a cooler thermostat in it this year. I have changed a LOT of parts on this thing, but I believe this specific issue to be pre-existing as it has issues with bogging under power while hot before I did anything.

I put in a new cap and rotor and a new Duracell dual purpose battery. A friend recommended a brilliant idea - add a relay to get good voltage to the ignition coil. I did so, and have a healthy 12.1 volts at the coil. BUT.... same problems! Boat fires right up when cold, runs strong, but if I cruise around and get it up to temperature then shut it down, it will refuse to restart.

The ONLY other thing I can think of is to replace the ignition module. I think it's a pretty likely cause from what I'm reading. The wires, cap, and rotor are all brand new. The plugs have about 10 hours on them and they all look good.

I noticed both boats in these posts are ‘93 models. Thanks to the input from waterlogged, I realized that I had replaced my IE module on my ‘92 with the incorrect one (PNX-95182] about 3 years ago. It recently failed similar issues as yours. But......Most likely your ‘93 came with OEM EI module (which is no longer made). If so, the PNX-95182 referenced above is the WRONG module. You need the PNX-95189. See my recent thread:
https://teamtalk.mastercraft.com/sho...d.php?t=105073

[Slide]

Thanks for the tip - my boat had aftermarket EI installed by the previous owner, it's a Mallory YL type. Summit Racing thankfully is local, and they carry most of these parts on the shelf. They didn't have the module, but I was able to get it on Amazon Prime.