K
kevin johnson
Guest
" Original message is below.
" Original message is below.
The mechanic ran a lake test and got it to act exactly as I had said. Sure enough, the engine was starving for fuel at idle. The fuel system was fine, he said my carb rebuild looked perfect, but no real problem was apparent. The solution was to drill out the low speed jets to 0.060" and that did the trick. It takes off like a charm now and runs like a champ at WOT.
He seemed to think there's a small leak somewhere in the crankcase allowing stray air in that's making it too lean at idle. I imagine a rebuild is the only was to solve a problem like that. THe next question is do I even bother with this old monster, or do I sell it and upgrade the whole thing? I have all fall & winter to think about that.
KJ
---------Original message-------------------------
OK, so I checked everything I know how to, gave up, and took it to the shop. The mechanic said I have good spark, the carbs are synchronized, and compression is
good. The only problem he found was a bad thermostat, so he replaced that. However, I took it out tonight and it ran great for a while and then bam, the "bog & die after
an idle zone" syndrome struck again. I am at wits end! He said nothing about the fuel pump, but I imagine he checked it (that's one question I have for him tomorrow).
The thing that gets me is that twice on Saturday it would only run at about 1700 RPM and die if I tried to accerelate. It did this for about 10 minutes and then finally the
RPM climbed and I had full power. It did that once for about 5 minutes tonight.
So my next thought is the ignition system, if it's not fuel related. Is it possible for an iginition component (charge/sensor coil, charge/sensor magnet, stator, rectifier,
powerpack) to work OK at high speed or when the motor is cool and maybe heat up while idling and fail when spark advance is needed (acceleration)? Or, it works OK
when inspected (i.e. the cowling off so it's cooler) but then fails when it's on. The is the only other thing I can think of is something like this. I ran it for a while Saturday
with the cowling off and the problem still was there, however this was after I had already run for about 30 min, so there was already heat buildup.
I'm somewhat leaning a little toward fuel since once tonight when I bumped the choke quickly that made it take off, although that may have just been coincidence.
However, bumping the choke other times, and every time Saturday, only resulted in the motor dying. What about a reed valve. Can those heat up and not function
properly?
Please, any & all help/information is needed & appreciated. This is a fine, strong motor and this problem is driving me nuts!!!
Thanks,
Kevin "
" Original message is below.
The mechanic ran a lake test and got it to act exactly as I had said. Sure enough, the engine was starving for fuel at idle. The fuel system was fine, he said my carb rebuild looked perfect, but no real problem was apparent. The solution was to drill out the low speed jets to 0.060" and that did the trick. It takes off like a charm now and runs like a champ at WOT.
He seemed to think there's a small leak somewhere in the crankcase allowing stray air in that's making it too lean at idle. I imagine a rebuild is the only was to solve a problem like that. THe next question is do I even bother with this old monster, or do I sell it and upgrade the whole thing? I have all fall & winter to think about that.
KJ
---------Original message-------------------------
OK, so I checked everything I know how to, gave up, and took it to the shop. The mechanic said I have good spark, the carbs are synchronized, and compression is
good. The only problem he found was a bad thermostat, so he replaced that. However, I took it out tonight and it ran great for a while and then bam, the "bog & die after
an idle zone" syndrome struck again. I am at wits end! He said nothing about the fuel pump, but I imagine he checked it (that's one question I have for him tomorrow).
The thing that gets me is that twice on Saturday it would only run at about 1700 RPM and die if I tried to accerelate. It did this for about 10 minutes and then finally the
RPM climbed and I had full power. It did that once for about 5 minutes tonight.
So my next thought is the ignition system, if it's not fuel related. Is it possible for an iginition component (charge/sensor coil, charge/sensor magnet, stator, rectifier,
powerpack) to work OK at high speed or when the motor is cool and maybe heat up while idling and fail when spark advance is needed (acceleration)? Or, it works OK
when inspected (i.e. the cowling off so it's cooler) but then fails when it's on. The is the only other thing I can think of is something like this. I ran it for a while Saturday
with the cowling off and the problem still was there, however this was after I had already run for about 30 min, so there was already heat buildup.
I'm somewhat leaning a little toward fuel since once tonight when I bumped the choke quickly that made it take off, although that may have just been coincidence.
However, bumping the choke other times, and every time Saturday, only resulted in the motor dying. What about a reed valve. Can those heat up and not function
properly?
Please, any & all help/information is needed & appreciated. This is a fine, strong motor and this problem is driving me nuts!!!
Thanks,
Kevin "