Problems starting

[The Fifth Lady]

1987 I/O 350 5.7L OMC

Having problems with BOTH cold start and warm start. Intermitent problem. Choke OK, new Fuel Filter, plugs OK. She runs great when running, but starting is an issue.

Any ideas? Thank you...

 

[Don S]

Re: Problems starting

What are your starting procedures? You aren't just hitting the key and waiting for it to run like a car are you? They are EFI, your engine is carbed and takes some extra steps.

 

[Gary H NC]

Re: Problems starting

When was the last COMPLETE tune up? Plugs,wires,cap,rotor,points,timing and dwell set ect..? That would be a good starting point..

And what Don says....starting procedure? Push throttle all the way forward to set choke when cold,pull it back to just about idle position and try to start.sometimes it takes a couple pumps on the lever to get gas in the engine..

 

[The Fifth Lady]

Re: Problems starting

Thank you both. Normal procedure for Cold Start is pumping throttle (to get fuel) while cranking ignition key.

Plugs look good and are hiting and Fuel Filter new...but not sure of last COMPLETE tune up.

 

[Don S]

Re: Problems starting

I would sure do a full tuneup other than just the plugs, including points, condenser, cap and rotor. Set the dwell, then the timing, then adjust idle mixture and speed. Then see how it starts.
If the points are building up high resistance, that will sure cause starting problems.

 

[The Fifth Lady]

Re: Problems starting

Thanks Don. Here is the longer, more detailed version. I will certainly take your advice re the tuneup, but wondering if you have any more insight based on the full story below...I greatl appreciate your response(s)

Initially, a problem surfaced when she stalled (going from reverse to neutral) and would not restart after she had been running for an hour. I thought she was flooded and finally started her and got home.

A few days later on the next session, I could not get her started. My efforts put a strain on the battery,but finally got her started. I began to think that this was a float problem and she was getting too much gas and flooding. We tapped the carb and thought maybe problem solved. I let her run for a half hr, then off and she cranked right back up w/no issue. Or perhaps this was a choke issue. In any event, I figured a Fuel filter would not hurt, w/ the Ethanol and water issues I hear about.

2 days after that on my next session, I replaced the Fuel Filter and noticed a good bit of water in the filter. I had a hard time getting her started and figured it was the water left in the line/ carb. My start attempts put a strain on the battery and I ended up getting her started with a Jumper box. I ran for 30 min's to get a little charge back.

2 days after that, my goal was to finally take her out, run her for a while at 4k rpm's to get a charge and run the fresh fuel and Star-Tron I added into the tank. After 3 cranks and my buddy manually holding the choke open a quarter inch, she fired up. (I had him mess w/the choke b/c before even cranking, we removed the Arrestor and choke was open). I ran her for an hour trip, and noticed that both my dash Meter and GPS noted the Batteries (2 w/ 650 Cranking Amps) were at 14volts. Then entering a marina, she stalled when going from reverse to neutral. Trying to start her in neutral was unsuccessful and so was pumping. After only 3 cranks or so, I was surprised that my batteries were very low/done. I got a tow to a slip, then proceeded to try her (w/ a Jumper Box) a few times without success. We even used some Starting Fluid. After letting her sit a bit, she finally started and got us an hour back to our home marina.

Backing into my Slip, she stalled again going from reverse to neutral. I tried to start her in neutral immediately and got nothing and the batteries again seemed weak. 20 minutes later, she fired right up.

Every time I think I am onto the root of my issue, something else happens and I an CONFUSED! To summarize, my issues seem to be A) Cold Start B) Warm Start and C) Battery (shouldn't the alternator work fine charging after an hr run at 14v?). Connections seem to be good and batt's are 3 mo's old.

Any help would be greatly appreciated!!! THANK YOU!!!!

 

[Don S]

Re: Problems starting

My guess is you are having problems with the shift interrupt (ESA) system on the boat.
This temporarily kill half the cylinders so the engine will missfire a little bit to allow the shift dogs to disengage.
Now, if you have defective shift interrupt switch, or a linkage problem, then it could be holding the shift interrupt system engaged. This would kill the engine if it wasn't running good to begin with. May take a while for the shift interrupt switch to disengage and allow fire back to the engine.

As far as charging goes, if you have 2 dead or very low batteries, you need about 150 to 200 amp hours put back into them.
An alternator run on an engine at 2000 rpm would be seeing about 40 to 45 amps per hour going into the batteries. So a short amount of running will not fully charge the batteries. Then when you have to keep cranking, you loose what little you put in.

 

[The Fifth Lady]

Re: Problems starting

Don,

Thank you much. That info is very helpful. A few small follow up questions:
1. Would the misfire you speak of be when running, or when trying to start, or both?
2. Is there a way to manually adjust/ mess with shift interrupt switch to get her going if needed in a pinch?
3. Is this shift interrupt issue a simple problem, inexpensive problem or more complicated and costly?
4. Could this be as simple as a linkage problem with the choke and bi-metalic coil? If the linkage is missing....
5. I understand your rule of thumb for charging the batteries via the alternator (thanks!). How would running at 4000 rpm impact that? Would I simply get double the amps per hour going into the batteries (thus 80 to 90 amps per hour)?

THANK YOU AGAIN. I REALLY APPRECIATE IT!

 

[Don S]

Re: Problems starting

1. Would the misfire you speak of be when running, or when trying to start, or both?

It should only happen for a split second when shifting out of gear. BUT, if something in the system is defective, it may last for hours till it frees up.

2. Is there a way to manually adjust/ mess with shift interrupt switch to get her going if needed in a pinch?

You can look on the shift plate on the engine where the Y shaped bracket is, and see if it's centered and not pushing on the switches.

3. Is this shift interrupt issue a simple problem, inexpensive problem or more complicated and costly?

All depends on what is wrong with it. I'm not an OMC guy, so not the best guy to explain that system.

4. Could this be as simple as a linkage problem with the choke and bi-metalic coil? If the linkage is missing....

I doubt it, but I have learned to never say never.

5. I understand your rule of thumb for charging the batteries via the alternator (thanks!). How would running at 4000 rpm impact that? Would I

Very little difference after about 2K. You only have maybe a 50A alternator, and the regulator only allows so much output, and it tapers off very quickly after the initial surface charge.

 

[wire2]

Re: Problems starting

OMC has the esa control on the shift control box just behind the distributor on a 5.7. There's 2 small limit switches on the cover. 1 is the neutral start, the other is for the esa. It has black & blue wires to a black rubber plug. The other side of the plus goes to the interupter module, black plastic case, 4.5" long, 2" wide.

 

[CharlieB]

Re: Problems starting

Whoa, guys!

Points?

Get out the test light or a volt meter,

disconnect the TWO wires on the + side of the coil

Seperate them, turn the key on, one shoud be switched hot off the ignition switch, the other should be triggered hot as the starter is engaged.

I bet a dime to a donut you have a poor contact in the starter solenoid and the second lead to the coil stays dead, makes them very hard to start.

 

[The Fifth Lady]

Re: Problems starting

Don S...Thank you again, very helpful. As for item 1, I would assume it's the split second...as sometimes there is a very small lag when going WOT to get on plane. Could that be the misfire you speak of?

Wire2....Thank you as well. I appreciate the description, but what exactly would I test, replace or look for?

CharlieB...Thank you too. That is a good, quick test and would make sense for the starting problem; however, the shift interrupt issue that DonS speaks of could be the root of the stalling problem (intermittently when coming in and out of neutral).

Thank you all again for the feedback...