terry 5.2m
Cadet
- Joined
- Jul 30, 2012
- Messages
- 26
I perfomred a compression test on my 77 115Hp V4 Johnson Sat.
Instead of using the key to turn over the engine I did it the old fashioned manual way by using the pull rope. I didnt want to risk damaging the electrical components.
I had the battery power disconnected, Throttle at WOT, the fuel line disconnected and no key in the ingition to be safe. I left the plugs and wires installed on the other three cylinders not being tested.
Test order went #1, #3, #2, #4 just so I worked on one side at a time.
Cylinder #1 test went fine (other than the fitting a little loose the first go around) but when I was into my third pull on cyl #3 I notice my tilt had bled out and the motor was starting to dig into the dirt and the prop was as well when I tried pulling the rope. no big deal. I hooked up the battery raised the tilt back to 90deg and put some blocks to keep the motor from moving as the tilt bled out (apparently my next project).
Here is where it gets worrisome. I forget to unplug the battery before I resumed my compression check on cyl #3. I pulled maybe 3 times before I realized I had not unhooked the battery.
I read the Solec and it specifically stated to make sure the plug wires were ground while perfomring the test but the #3 wire was not grounded while I did the 2 to 3 pulls.
My question is: Did I potentially cause damage to the iginition system? Or is it that no electricity gets to the coil if throttles is at WOT and no key in the ignition. I tried reading the schematic but still not sure.
I unhooked the batt and proceeded with the compression check.
Once finished I was looking over the engine and noticed the #4 coil has a crack in the black insulation all the way across. I am not sure if that had been there or not as I am short and the only reason I noticed it this time may have been because I had the motor staright up and down so the coils were at eye level. When in the full tilt position the crack is such that I may not have noticed it previously since it is more towards the bow side of the coil.
I have been having some what of a rough idle and I had put fresh gas in the tank. cleaned the filter, changed the plugs and ran engine tune up per bottles instructions. Idle had improved but not perfect so I was looking at rebuilding the carbs but I wanted to check the compression first. But now I wonder if the coil had been like this the whole time and created the bad idle. The #4 plug was the sootiest/wettest when I swapped the plugs...not by a lot but still.
Incedentally
#1: 112 (gauge not tight), 115
#2: 115, 115
#3: 115, 115
#4: 119, 118
Comments appreciated.
Scott
Instead of using the key to turn over the engine I did it the old fashioned manual way by using the pull rope. I didnt want to risk damaging the electrical components.
I had the battery power disconnected, Throttle at WOT, the fuel line disconnected and no key in the ingition to be safe. I left the plugs and wires installed on the other three cylinders not being tested.
Test order went #1, #3, #2, #4 just so I worked on one side at a time.
Cylinder #1 test went fine (other than the fitting a little loose the first go around) but when I was into my third pull on cyl #3 I notice my tilt had bled out and the motor was starting to dig into the dirt and the prop was as well when I tried pulling the rope. no big deal. I hooked up the battery raised the tilt back to 90deg and put some blocks to keep the motor from moving as the tilt bled out (apparently my next project).
Here is where it gets worrisome. I forget to unplug the battery before I resumed my compression check on cyl #3. I pulled maybe 3 times before I realized I had not unhooked the battery.
I read the Solec and it specifically stated to make sure the plug wires were ground while perfomring the test but the #3 wire was not grounded while I did the 2 to 3 pulls.
My question is: Did I potentially cause damage to the iginition system? Or is it that no electricity gets to the coil if throttles is at WOT and no key in the ignition. I tried reading the schematic but still not sure.
I unhooked the batt and proceeded with the compression check.
Once finished I was looking over the engine and noticed the #4 coil has a crack in the black insulation all the way across. I am not sure if that had been there or not as I am short and the only reason I noticed it this time may have been because I had the motor staright up and down so the coils were at eye level. When in the full tilt position the crack is such that I may not have noticed it previously since it is more towards the bow side of the coil.
I have been having some what of a rough idle and I had put fresh gas in the tank. cleaned the filter, changed the plugs and ran engine tune up per bottles instructions. Idle had improved but not perfect so I was looking at rebuilding the carbs but I wanted to check the compression first. But now I wonder if the coil had been like this the whole time and created the bad idle. The #4 plug was the sootiest/wettest when I swapped the plugs...not by a lot but still.
Incedentally
#1: 112 (gauge not tight), 115
#2: 115, 115
#3: 115, 115
#4: 119, 118
Comments appreciated.
Scott
