Flames out lower unit 77 Johnson 115

whitejamie99

Petty Officer 2nd Class
Joined
May 12, 2005
Messages
105
After rebuilding the water pump on my 77 Johnson 115 (115ETL77), I made an attempt to start the engine with the muffs attached. It cranked well and would pop once and then starter disengaged. My son was on fire watch and noticed a blue flame in the lower unit when it popped. We tried it several more times and still wouldn't fire. Getting good spark on # 1 and # 3 (didn't check the others - got late). I will try the troublehoot list from the FAQ.<br /><br />Had to remove the lower carb to get at the shift rod during the repair and the shifter mech was very stiff after the reinstall. How do I adjust and troubleshoot this item?<br /><br />My last question is - did this flame damage anything or is this normal since its trying to start. I dont want to tear down the lower unit again if this is a normal circumstance but I dont want to destroy the lower unit either.<br /><br />HELP!<br /><br />Jamie White
 

CATransplant

Admiral
Joined
Feb 26, 2005
Messages
6,319
Re: Flames out lower unit 77 Johnson 115

Good for you for having a fire watch. The flame out of the lower unit was doubtless coming from the exhaust, and probably didn't do any damage.<br /><br />That is a symptom, though, and is worth exploring, especially since your motor didn't start but just popped and shot a flame out of the exhaust.<br /><br />Did you change plugs recently or do any other work on the engine? This sounds suspiciously like a couple of switched plug wires. I see you checked spark on one side. Is it possible that you had switched two plug wires? I've sure done it, and that will cause a misfire, which can cause the blue flame out of the exhaust when the plug fires while the exhaust port is open.<br /><br />Betcha that's the problem, but don't worry about the flame damaging anything.
 

Straightup

Petty Officer 1st Class
Joined
Apr 5, 2005
Messages
317
Re: Flames out lower unit 77 Johnson 115

I'll be changing the impeller on my '84 70 shortly. Interested to hear how you come out. <br /><br />Jeff
 

whitejamie99

Petty Officer 2nd Class
Joined
May 12, 2005
Messages
105
Re: Flames out lower unit 77 Johnson 115

I may have # 1 and # 3 crossed. My understanding of the cylinder #'s is like this:<br /><br />Port top 2 Starboard top 1<br /><br />Port bottom 4 Starboard bottom 3<br /><br />If this is correct - then its just a matter of making sure of the coil #'s on the top of the heads. This is how I think the coils are #'d.<br /><br />port left = 4<br />port right = 2<br />starboard left = 3<br />starboard right = 1<br /><br />I did try swapping the # 3 and the # 1 and it didnt start and didnt pop - just cranked.<br /><br />How can I verify the above
 

CATransplant

Admiral
Joined
Feb 26, 2005
Messages
6,319
Re: Flames out lower unit 77 Johnson 115

Check your manual to make sure. I don't have that model motor, so I can't tell you. The symptoms, however, sound like switched wires. It could be other things, though. That's where I'd start.
 

McGR

Senior Chief Petty Officer
Joined
Jun 19, 2004
Messages
664
Re: Flames out lower unit 77 Johnson 115

Here's the cylinder arrangement:<br /><br />Port Top: 2<br />Port Bottom: 4<br /><br />Starboard Top: 1<br />Starboard Bottom: 3<br /><br />Here's the coil order port to starboard:<br />4,2,1,3 (P Bottom, P Top, S Top, S Bottom)<br /><br />I hope this helps.
 
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