Won't Start, Timing Issue

[miles917]

'88 4.3l OMC Cobra

I'm feeling a bit dumb. Had my boat out the other day, started and ran to 1800 RPM and then would backfire. I figured timing and didn't run the boat much when I noticed I was still getting water in my gear oil. Not a ton of water so I drained the gear oil, replaced it and will get to that later.

Problem was I was looking at my plug wires and they were not in the correct order so I put them into the correct order. Would the boat have run if they were incorrect? Maybe they were right and It was me that screwed up.

So I got the engine in compression cycle, cranked the engine with a 5/8 wrench to 0 TDC and started wire #1 with the rotor pointed at it and then went around with the rest. I'm positive I did this correctly with firing order 1,6,5,4,3,2 clockwise.

Went to start it and it just cranks. Plugs are black now but and they were new. Wires, cap and rotor are new. Havent done points but was getting ready to when I screwed things up. Right now I'm charging the battery as its almost dead from the cranking. On a side not, the negative terminal on the battery got very hot.

I probably should be doing some more troubleshooting before posting on here but my heads spinning and I need to wait for the battery to charge. Any ideas are appreciated. Thanks.

 

[Limited-Time]

Re: Won't Start, Timing Issue

Quick question...............what made you think the wire orientation was off in the first place??.........First off are you getting spark to the plugs..................second are you sure you were TDC on the compression cycle..............as for the neg post getting hot it will do that under a heavy current draw..............like extended cranking.

 

[miles917]

Re: Won't Start, Timing Issue

I was looking at the wires last night and thought #3 was next to #1 so I took them all off except for #1 and put them in order. I very well could have been wrong or confused. Then after that at somepoint I removed the cap and cranked the engine so now I figured just take it all off and start over.

As far as TDC on compression cycle, I did what I read on here. Removed all plugs, wires and cap. I didn't have anyone to help so I used an idea on here that said plug the #1 plug hole with a rolled up paper towel. I cranked the engine and it shot out on the first crank. Then I manually cranked the engine to 0 TDC. It was only an inch or so away.

Does that sound correct? Would the fouled/black spark plugs not fire at all?

Can you tell me the quick way to check for spark at the plugs? Thanks.

 

[MikDee]

Re: Won't Start, Timing Issue

That 4.3 V6 will have the TDC marks lined up on both Cyl #1, and Cyl #4, Both pistons will be at TDC at the same time, You have to determine if the cam is set to fire on #1, or #4? (Remember, It takes 2 revolutions of the Crank, to make 1 turn of the Cam, one firing cycle) Your Dizzy could be 180 degrees out. Set it up now so that your rotor is facing terminal #1, and the Crank timing marks are aligned, then take out your Dizzy, and put the Dizzy body back in at the same spot, but face the rotor at #4, and try it.

 

[MikDee]

Re: Won't Start, Timing Issue

Unless you haven't taken out the distributor? Then don't worry, just make sure your wires are on right, 1,3,5 on the port side, and 2,4,6, on the Starboard side, 165432 firing order clockwise, like you figured. If it still don't fire, check your points, they maybe worn out, & not opening!

 

[Don S]

Re: Won't Start, Timing Issue

As far as TDC on compression cycle, I did what I read on here. Removed all plugs, wires and cap. I didn't have anyone to help so I used an idea on here that said plug the #1 plug hole with a rolled up paper towel. I cranked the engine and it shot out on the first crank. Then I manually cranked the engine to 0 TDC. It was only an inch or so away.

Yes, you got it on #1 TDC on the compression stroke. with that process.
Now, just look at the rotor, it is pointing to #1 spark plug wire

 

[Limited-Time]

Re: Won't Start, Timing Issue

When I set the engine at TDC on #1......................... I use 1 of two methods.................If can pull the valve cover I watch the intake valve until it starts to close, then I rotate the timing mark to TDC.............at which time both valves on the #1 cylinder are closed. If i can not remove the VC I pull all the spark plugs, using a socket on the crank pulley I turn the engine over while I hold my thumb over the #1 plug hole..............when I feel the beginning of the compression stroke I rotate the engine to the TDC timing mark.

 

[miles917]

Re: Won't Start, Timing Issue

Thanks Guys for the help!

Don, I had all the wires and cap off when I did that and then put the #1 wire where it was facing. It still did not start.

Heres what I did just now. I went out, manually cranked the engine back to 0 TDC. Pulled the cap to see the rotor direction and re-did the wires again. Again, didn't start. Manually cranked the engine back to TDC which was only a 1/4 turn or so. This put the rotor facing #1 again. So I cranked 1 more rotation to TDC again. Pulled the cap and the rotor was 180 degress from its last position. I re-did the wires to how the rotor was now pointing and she started right up.

Seems like a trial and error way but It worked. Now I get to buy new plugs again and get the timing light out.

Thanks again Mik-Dee, Limited-Time and Don

 

[Don S]

Re: Won't Start, Timing Issue

Once you get the engine up on TDC, put #1 plug wire on the terminal the rotor should just be getting to.