Starting problems. Bad head gasket?

[Angrywasp]

Well I came back from deployment and tried to start my boat. It wouldn't even turn over but the starter was trying. I pulled the plugs out and found that the rearmost cylinder and the one forward of it had some in it as well. I remembered that I hadn't drained the motor but since it was over summer cracking the block with freezing wasn't a concern. I checked the oil and it's clean without a trace of water in it. Then I cranked the motor over with the plugs out and proceeded to cover myself, the boat, and my truck with 3 month old water that was full of carbon from the cylinders. Well after cleaning everything up and making sure the cylinders were dry and the plugs clean I tried to fire it up again. Still no start and it's getting gas. I picked up compression tester and the cylinders read 100, 50, 110, and 90 from front to back. I'm leaning towards the head gasket being bad but I wanted some more experienced people's input. I can do all the engine work myself so it would just be the parts and time that I needed. Anyone have something else I should check?

 

[ghettoyacht]

Re: Starting problems. Bad head gasket?

With that compression reading, the head has to come off. re-assess after an examination of the cylinders. I think a head removal may also be in my future.

 

[Don S]

Re: Starting problems. Bad head gasket?

Without running the engine, and water being in a couple of cylinders, I wouldn't be to concerned about the compression numbers just yet.
First thing you need to do is get the water out of the cylinders and dry the plugs. Make sure you have spark, and pour some gas in the carb and see if it will start.
DO NOT put water to the engine yet. You can even remove the impeller until you get it running.
Once you get it to where it will start, start it up and let it high idle (around 1000-1200 rpm)with the choke off for about 15 seconds with no water.
Then try a new compression test.
With water in those cylinders sounds more like a failed riser to manifold or riser gasket than a head gasket.

 

[ghettoyacht]

Re: Starting problems. Bad head gasket?

i'm always too eager to tear things apart even if they don't need it. better listen to don.

 

[TilliamWe]

Re: Starting problems. Bad head gasket?

"Starting problems. Bad head gasket?"

No. Exhaust manifold issue. Water in a cylinder or two (or 4), in a MARINE engine, is first and foremost and EXHAUST issue.

 

[Angrywasp]

Re: Starting problems. Bad head gasket?

Well I pulled the plugs, cleaned them with gas and a toothbrush, and used my shop vac with a piece of 1/4" clear tubing to vac the cylinders out. I only got a very small amount of water out of them (couple of drops at most). I also checked the plug wire and one was bad (broken core) and 2 others were out of spec on resistance. I replaced them and cleaned the battery connections and tried to start her again. She turns over better but still doesn't start. I sprayed gas in the carb even though I could see the gas spraying in from the normal carb ports but she didn't even try to fire. Kinda bummed about it since the weather has been great for boating the past few days.

 

[Don S]

Re: Starting problems. Bad head gasket?

Using a vac to suck water out of a cylinder through a 1/4" tube is not going to work.
Crank it over with no plugs in so you have the rpm and it will get more water out.
May take several attempts, but you have to do it.
Running with bad plug wires is not good for an engine.

Kinda bummed about it since the weather has been great for boating the past few days

.

Think preventive maintenance during the off season, beats repairs during the boating season.

 

[Angrywasp]

Re: Starting problems. Bad head gasket?

I had already cranked it over with the plugs out until nothing else came out of the cylinders (Took forever to clean everything up). That's when I found it wouldn't start. It had run fine before then (GPS's at 38.6 mph). I had it out on the water about a week before I had to deploy. I melted the hydraulic line for the trim motor which put the boat OOC until I replaced it. I'd owned the boat for about 3 months before that so I hadn't gotten around to a lot of preventative/lay up maintenance (I did change the drive and engine oil). I'm pretty sure that I broke the core on the plug wire while working on it since it wasn't missing when I left. Just checked for spark since the sun went down and there's not any. Now I guess I'll have to search the electrical diagrams. Joy.
Edit: I guess I'm going to tinker with the distributor tomorrow since I've got power everywhere it needs to be but nothing is coming out of the distributor.

 

[Angrywasp]

Re: Starting problems. Bad head gasket?

Okay. I have now replaced the plug wires, plugs, cap/rotor, and the coil. I still can't get it to spark. I've got 12v to the cap but it won't spark. I don't have the tools or know how to test the ignition module or the E.S.A module and don't know if the local shops can either. I'm pretty much at a loss for how to continue or what to check now. Anyone got any ideas of how to proceed?

 

[Don S]

Re: Starting problems. Bad head gasket?

Disconnect the ESA module and see if you have spark.

 

[Angrywasp]

Re: Starting problems. Bad head gasket?

Disconnected ESA and still no spark. I guess I'll pull the ignition module and see if the local shops can check it for me.

 

[Don S]

Re: Starting problems. Bad head gasket?

There is more than just the module that will cause a no spark problem.
Do you have power to the purple wire going to the coil ???????
Can we assume you have the EST distributor? Do you have a service manual and gone through the troubleshooting procedures?

 

[Angrywasp]

Re: Starting problems. Bad head gasket?

Yes it does have the EST distributor. I've got power to the blue/purple wire to the coil. The other plug to the coil doesn't have power to either wire (red? and black). Thanks for taking all this time to help me Don.

 

[Don S]

Re: Starting problems. Bad head gasket?

Hang around for a bit, I'm going to post some pictures. You shouldn't have a red or a black going to the coil. Never heard of a blue/purlple wire either.
You might want to post some pictures of what YOU have.

 

[Don S]

Re: Starting problems. Bad head gasket?

Here are the wire color codes for any OEM EST distributor I have ever seen.

You also need to disconnect the gray wire from the back of the tachometer and make sure the tach is not shorting out and killing your spark.

 

[Angrywasp]

Re: Starting problems. Bad head gasket?

I'll check all the wiring and connections out tomorrow after I get home from work. The wire colors are fairly sun faded going to the coil.

 

[Angrywasp]

Re: Starting problems. Bad head gasket?

WOOHOO! It's alive again. I checked all the wires and cleaned the contacts but it still wouldn't spark but the readings got better. I pulled the ignition module and the ESA and went to the shop that I knew used to be a OMC shop. I walked in and the manager looked at what was in my hands and said "No spark?". I said yeah and he told me exactly what my symptoms and indications were and then told me to get a new ignition module at a local car parts store and I would be good to go. I did and the boat fired right up. Thanks for all the help Don and I stole your picture since the ones in the manual aren't nearly as easy to work with. Now to work on the pesky shifting issue.