timing advance

[KJM]

i just switched over to electronic ignition and set the timing. the specs call for 6 degree btdc but i found the engine didn't idle smooth at that and seemed to like 10 degree advance better. any harm in leaving it at 10? will this cause detonation? i had her out yesterday and she didn't seem right, she seemed to be straining at higher rpm's and i had trouble with her stalling when putting into gear. i think this might be a carb problem and unrelated as the stalling when putting into gear was also happening last year. any thoughts? the engine is a inline 6 165hp

 

[Bondo]

the specs call for 6 degree btdc but i found the engine didn't idle smooth at that and seemed to like 10 degree advance better.

Ayuh,..... At 10*, detonation is quite possible,......

The carb could be the Problem,.....

 

[KJM]

yeah i think the carb may be the problem too. am i correct thinking the idle mixture screws only affect the mixture at idle? i have them out 2 1/2 turns. the rpms at idle are about 400. does this seem ok? i'll probably have to take apart the carb and rebuild it i guess.

 

[achris]

1. Correct. Idle mixture screw only effects idle mixture.
2. Then turn the idle speed screw in until the idle speed increases to 650 rpm.

Chris. ...

 

[Scott Danforth]

One of the issues with base timing (besides chance of detonation) is engine vacuum increases at idle with more advance, and so does the chance of reversion

 

[KJM]

i put the timing back to 6 degrees btdc and adjusted the idle mixture screws in a bit until she idled at the highest rpms and then adjusted the rpms with idle speed screw. took her to a nearby small lake to try her and had the same problem. the boat will idle and go into gear no problem on the hose but in the water she will idle but die when i put her in gear. it seems worse when she is hot after a good run. i started her at the lake and had a little difficulty getting her not to stall when engaging the gears but finally got going and had her up and down the lake a few times at varying speeds and she seems good. stopped and she was idling good,put her in drive again and she stalled. then i had trouble even getting her started and when i did she would die again when engaging forward or reverse. i ended up rowing back to my trailer. i think she is flooding but how would i know for sure. i don't know much about carbs but i have a feeling i'm about to learn!

 

[KJM]

actually after reading a lot of posts about similar problems i'm starting to think maybe my shift interupteor switch may be the problem. think i'll try that before messing with the carb......