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Mariner inline 6 115 no start

J

JimB1

New member
I have what I believe is a 1978 Mariner 115 inline 6 with CDI ignition. I bought it on a trashed boat a couple of months ago to put on a pontoon. After I got it home I replaced the corroded wiring harness and cleaned the carbs. The motor started easily and ran great. I had a buyer for the old boat and trailer so I pulled the motor and put it on a stand while I rebuilt the pontoon transom. Mounted the motor on the pontoon and it will not start. No smoke, no backfire, no sign of trying to start at all. Spark jumps my 1/2" tester, hot blue spark. Primed each cylinder with premix fuel. Nothing. Checked static timing, #1 fire a 5 degrees btdc at idle and 20 btdc at full throttle. However, when checked with a timing light at cranking speed, #1 fires way retarded, maybe 30 or 40 degrees. I've tried to attach a photo showing approximately where the timing light fires without success. Any ideas why this motor won't run or the strange timing issue?

Thanks
 
Is the timing belt worn / loose ?-----Is the flywheel assembled correctly ?---Clean the inside of the distributor cap.-----Look into setting the timing correctly.----Fuel in the spark plug hole should be making some noise !!
 
Sounds like the timing belt slipped a tooth or so. Fix that up, try a little ether, and it should go.

Jeff

PS: With the belt off, see if the distributor turns freely. If not, the bearings are shot and it will screw up again.
 
racerone said:
Is the timing belt worn / loose ?-----Is the flywheel assembled correctly ?---Clean the inside of the distributor cap.-----Look into setting the timing correctly.----Fuel in the spark plug hole should be making some noise !!
Click to expand...

Thanks for the reply. Belt is tight. Flywheel is correct, with #1 at TDC timing indicator is at 0. The motor was starting and running before I pulled it off the old boat. Turning the engine over by hand #1 fires at the correct time (5 degrees btdc). But, when turned by the starter the light flashes way retarded, probably an inch past the timing strip on the flywheel. I know this makes no sense, but I tried a dozen times with the same result.
 
fastjeff said:
Sounds like the timing belt slipped a tooth or so. Fix that up, try a little ether, and it should go.

Jeff

PS: With the belt off, see if the distributor turns freely. If not, the bearings are shot and it will screw up again.
Click to expand...

Thanks for the reply!

The arrow on the distributor pulley points directly at the crank when #1 is at TDC, so I believe the static timing is correct. Turning the engine over by hand #1 fires at the correct time (5 degrees btdc). But, when turned by the starter the light flashes way retarded, probably an inch past the timing strip on the flywheel. I know this makes no sense, but I tried a dozen times with the same result. The distributor turns smoothly.
 
Move the distributor one tooth until it's no longer retarded and try again. I know: the fool thing ran before, so....Stuff happens.

jeff
 
Make sure timing light if it has a advance control is at 0° and it on #1 plug. I wouldnt start changing timing if everything lines up.
 
faztbullet said:
Make sure timing light if it has a advance control is at 0° and it on #1 plug. I wouldnt start changing timing if everything lines up.
Click to expand...

Thanks for the reply.

The light is a simple one. What has me perplexed is why I can turn the motor over slowly and hear every time the coil fires, and #1 fires at 5 btdc. Yet when turned over by the starter it shows to fire way retarded, clear off the timing sticker.
 
Pulled the distributor cap and took the timing belt off the sprocket. Turning the distributor by hand it fires with the rotor pointing exactly at where #1 contact would be. I'd measured earlier from where the #1 tdc mark on the flywheel is and where the timing light is flashing on the flywheel and its about 40 degrees btdc. So, pulled the distributor and found some corrosion on the shutter wheel at cranking rpm's. Thinking maybe the corrosion is causing some issues with the sensor. So, gonna look and see how the dang thing comes apart so I can get the corrosion cleaned up on the underside of the shutter.
 
Guys... I may have messed up. Got the distributor apart and the rotor/shutter was nasty on the underside too. Got it cleaned up and as I was going back I realized the index tab is not centered in an opening or solid area area, meaning there is an up and down side.... I always make a mark or take a picture when I disassemble something new to me. Unfortunately this time I took a picture, didn't think about the rotor not going back either way. Looked for a you tube about it and searched this forum without success.
 
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This is from the CDI instructions PDF it might be similar as to the position of the rotor trigger-disk.jpg
 
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