In the water with intermittent issue

[ashc2025]

OMC 3.0L 1990 electronic ignition 17' Bowrider

Took my boat out in the water after doing an cable adjustment yesterday. The gear shift worked great but I have an issue with the engine misfiring, sputtering, and dying on acceleration and cruising. I have replaced the entire ignition system exception being the distributor. Here's my issue:

The engine will stall and die with a quick acceleration from the throttle. Reverse or Forward. I can ease the throttle forward slowly and build up enough speed to plane out an cruise. At WOT I am touching about 3500 RPM. After about 20-40 min of cruising the engine began to sputter, back fire, then stall out. Restarting the engine after words is a bear. I can let the engine sit for about 10min and she will fire back up easily. The engine is a rebuild with a .04 overbore. I have tried advancing and retarding the timing by 2 degree increment with no change or alleviation in symptoms.

My instinct is telling me that the electronic ignition module in the Distributor is shot. I burned my fingers by touching the bottom of the distributor during timing adjustment. I've also heard that the counter weight in the distributor can become sticky and throw off the spin.

On muffs, the engine will start and accelerate without issue. Anything else I should be checking?

-Chris

 

[Bondo]

Re: In the water with intermittent issue

Ayuh,.... Sounds like it's runnin' outa Gas,... Check the fuel filters for crud...

 

[jerryjerry05]

Re: In the water with intermittent issue

I was thinking water??
Definatly a problem with the dist if it gets that hot.
Check the coil too.Does it get too hot to touch?
Voltage in to the coil? Voltage out?New coil? Automotive or the original?
Resister or not?
Your temp guage working? Sounds like it's getting hot.
.040's a lot.You rejet the carb? that far out might be running too lean,getting hot.
Do a compression test.

 

[ashc2025]

Re: In the water with intermittent issue

Ayuh,.... Sounds like it's runnin' outa Gas,... Check the fuel filters for crud...

The fuel filter is new, and the bowl is full of gas, with a rebuilt Carb (new gaskets and jet). I dialed each mixture screw out a quarter turn, maybe more for the slightly larger displacement?

I was thinking water??
Definatly a problem with the dist if it gets that hot.
Check the coil too.Does it get too hot to touch?
Voltage in to the coil? Voltage out?New coil? Automotive or the original?
Resister or not?
Your temp guage working? Sounds like it's getting hot.
.040's a lot.You rejet the carb? that far out might be running too lean,getting hot.
Do a compression test.

I sucked the tank dry and filled with new gas, so I don't THINK there's water in there. Distributor is super hot and I havn't replaced the rotor or cap since they are hard to find due to age. It's also a 2 wire instead of a 4 wire dist. There is a purple and pink wire disconnected. I've replace the coil as well. Tried a marine as well as an automotive coild with same results. Havn't checked voltage to and from the coil yet. Compression is good, and it's a new headgasket and pistons with the rebuild. No carb re-jet, just a stock rebuild. Might consider doing another rebuild? Or a re-man carb?

I just don't know what to try first LOL.

 

[bruceb58]

Re: In the water with intermittent issue

I dialed each mixture screw out a quarter turn, maybe more for the slightly larger displacement?

That's the idle mixture. Has no effect other than at idle.

I don't think its your timing. You do use a timing light right? You put it into base timing mode(depends on model)? Does the timing advance meet the spec in the manual over varying RPM?

A 1990 OMC used a Delco EST distributor I believe(easy to get parts for). What do you have? What is your model number?

 

[ashc2025]

Re: In the water with intermittent issue

I'm Using a regular timing light, nothing fancy. My manual says that I have an HEI distributor. I will have to tear it out to check otherwise. I Set the timing to 0 and then tried and advance and retard to remedy the issue, nothing seemed to help. As far as timing advance, the RPM woudln't go over 3.5k, so there wasn't a distinguishable move in timing, maybe 1-2 degrees.

 

[bruceb58]

Re: In the water with intermittent issue

What manual are you using? What is your model number?

If your timing is not changing between idle RPM and 3500 RPM, your advance isn't working.

If you truly have a 1990 engine, your distributor won't have advance weights if it has the electronic distributor. 1990 is when OMC transitioned from points so maybe someone put in a different distributor.
These are the various model numbers for a 1990
http://www.marineengine.com/parts/omc-parts/omc-boat-parts.php?year=1990&hp=3.0

Does this look like your ignition module?
http://www.marineengine.com/newparts/part_details.php?pnum=OMC3854003&ptype=&Engine=&Model=

Post a picture of your distributor.

My first inclination was that you have a fuel issue. This timing issue you just threw in where it doesn't advance over the RPM range just added another question though.

 

[ashc2025]

Re: In the water with intermittent issue

The model on the valve cover says 302BPRPWS. I've been using a Seloc, but I've heard they are good for kindling and that's about it.

I'm going to get it started put it one muffs and watch the timing and see if it moves. I havn't had time past few days. I snapped a few pics of the distributor as well.



I'm going to order another carb kit and see if that helps as well.

 

[bruceb58]

Re: In the water with intermittent issue

You need to set your initial base timing with a shunt plugged into the right hand connector. Not sure if your Seloc describes that process or not. If it does its probably wrong anyway but what you are doing isn't good at all.

 

[ashc2025]

Re: In the water with intermittent issue

I agree, I have maybe 2 - 3 hours on the motor now. I think I'm gong to bite the bullit go for this:

3.0L Delco Voyager EST Marine Electronic Distributor Kit

and a re-manfactured carb.

I can rule out fuel and ignition this way, and it comes with a shunt for timing. heavy purchase, but it's better to fix it rather than nickle and dime.

 

[bruceb58]

Re: In the water with intermittent issue

You realize that is the distributor you have and you can buy replacement parts for it right? Depends on how many parts you need to buy to see if its worth it or not.

 

[ashc2025]

Re: In the water with intermittent issue

You realize that is the distributor you have and you can buy replacement parts for it right? Depends on how many parts you need to buy to see if its worth it or not.

Well I know the rotating assembly is fine. So I guess just rotor, cap, module, and shunt pigtail. Not sure what to do about the carb though. They all have the fuel line on the right hand side instead of left. Maybe the bowls are interchangeable....hmm

 

[bruceb58]

Re: In the water with intermittent issue

Its weird that your timing isn't advancing. Almost like its permanently in base timing mode. I would investigate the wiring a bit before I bought a new module. Not sure if the wiring to the distributor is stock or not but I would investigate that a bit before I started throwing $$ at it.

 

[tonyjklh]

Re: In the water with intermittent issue

Its weird that your timing isn't advancing. Almost like its permanently in base timing mode. I would investigate the wiring a bit before I bought a new module. Not sure if the wiring to the distributor is stock or not but I would investigate that a bit before I started throwing $$ at it.

I had the same thing happen when I converted my points setup to an est distributor. I forgot to set the distributor to base timing and that caused it to not advance at hardly at all when revving. It sounds like he didn't set base timing correctly. That might be the problem with timing. But I should mention that even when my distributor wasn't working properly and was timed wrong it still ran pretty good

 

[tonyjklh]

Re: In the water with intermittent issue

also you don't need to buy a pigtail for the timing. go to your local salvage yard and get the wiring from any chevy est distributor, then cross wires# 3,4. and put wire #2 to positive power, don't use wire #1(black wire).