Krysstopher
Recruit
- Joined
- Jul 10, 2012
- Messages
- 3
I have been working on this qd 19 for the past few weeks on and off (very fun project). I have been doing a lot of tank testing in the back yard and a few hours on the water fishing with the family. This is after it has been sitting in family garage for 20+ years.
Runs good BUT...at above 5 mph the motor will 'jump' every 10-12 mississippi's (some describe it as hitting something in the water). It stays in gear and run smooth if I back off the throttle. If I try wot it gets more violent. So much so that the propeller pin (made of brass) has snapped three times now (while in test tank and once on the water). I replaced with steel for now. I have been adjusting the high speed carb needle until the tank water is black, but it never affects the 'cough' (rpms go way down blows smoke from being too rich). Low speed and idle work well. Engine starts in one or two pulls even after sitting a few days and doesn't die.
I have been replacing a lot of old gaskets and seals to fix visible leaks.
Rebuilt the carb with new kit and the entire magneto assembly, plug wires and plugs.
De-carboned the cylinder head and exhaust (too many years trolling in the past)
Replaced old fuel houses, connectors and old rusted tank with plastic.
Replaced impeller and lower unit oil twice (no metal pieces)
Sorry for being too wordy, but I have gotten the obvious engine problems solved with the listed items above, but the cough has changed little. I am just not sure where to look next (lower unit gear issues or crank seal maybe?)
Any tips would be much appreciated. Thanks.
Runs good BUT...at above 5 mph the motor will 'jump' every 10-12 mississippi's (some describe it as hitting something in the water). It stays in gear and run smooth if I back off the throttle. If I try wot it gets more violent. So much so that the propeller pin (made of brass) has snapped three times now (while in test tank and once on the water). I replaced with steel for now. I have been adjusting the high speed carb needle until the tank water is black, but it never affects the 'cough' (rpms go way down blows smoke from being too rich). Low speed and idle work well. Engine starts in one or two pulls even after sitting a few days and doesn't die.
I have been replacing a lot of old gaskets and seals to fix visible leaks.
Rebuilt the carb with new kit and the entire magneto assembly, plug wires and plugs.
De-carboned the cylinder head and exhaust (too many years trolling in the past)
Replaced old fuel houses, connectors and old rusted tank with plastic.
Replaced impeller and lower unit oil twice (no metal pieces)
Sorry for being too wordy, but I have gotten the obvious engine problems solved with the listed items above, but the cough has changed little. I am just not sure where to look next (lower unit gear issues or crank seal maybe?)
Any tips would be much appreciated. Thanks.
