Sifton/aftermarket cam chest gears
Knucklehead won't start
-
- Member
- Posts: 256
- Joined: Mon Apr 09, 2012 7:38 pm
- Bikes: '02 Fatboy, '47 Knuckle, '52Pan
- Has thanked: 60 times
- Been thanked: 11 times
Sifton/aftermarket cam chest gears
Finally took my '47 Knuckle out for a longer ride about 35 miles, rather then around the block trying to get used to a tank shifter, about 2 miles from home it started to spit and sputter I was doing about 40 mph, then it conked out, had to trailer it back home, I've been trying to get it started for the past 3 days, all it does is backfire through the carb, the motor is completely rebuilt including the M-35 Likert, and the generator, I have good spark, and it's getting gas, up until this it was running like a watch, 2 primer kicks and it would fire, when it was warm it started every time 1 kick,also no manifold leaks, and plenty of compression, any suggestions, Thanks Whitey
-
- Moderator
- Senior Member
- Posts: 8404
- Joined: Sat Nov 15, 2008 4:09 am
- Bikes: Multiple H-D, Ducati, BMW, Triumph, BSA,...
- Has thanked: 481 times
- Been thanked: 2954 times
-
- Senior Member
- Posts: 588
- Joined: Thu Oct 20, 2016 6:14 am
- Bikes: 42 WLA
47 EL
47 UL
52 FL
52 FL
54 FL
57 FL
63 FLH
2022 FXLRST - Location: Hawaii
- Has thanked: 171 times
- Been thanked: 56 times
Re: won't start
I just had the same exact thing happen to me on my FLH this week. It took me 3 or 4 days of trying to figure it out, drove me nuts. I changed the condenser once it started sputtering and back firing, my float was also way off so I adjusted that. Not sure which one was the issue or a combination of both but now it is running great again. At the same time I changed and re-gapped my points as well.
-
- Site sponsor
- Senior Member
- Posts: 1922
- Joined: Fri Jul 01, 2011 8:43 pm
- Bikes: 1969 FLF
1937 EL
1940 U - Location: san diego
- Has thanked: 1478 times
- Been thanked: 243 times
Re: won't start
If its still 6volt, your battery probably dead. Plus as has been mentioned, points, take the cap off and kick in the dark, once the battery is up to snuff.
-
- Senior Member
- Posts: 1407
- Joined: Tue Feb 05, 2013 12:25 am
- Bikes: 1950 panhead, 1999 FLHTCI, 1987 FLHTC custom
- Location: Daytona Beach
- Has thanked: 447 times
- Been thanked: 651 times
Re: won't star,
Fuel? Are you sure? Splash some gas in the carb mouth and try. Two miles is enough to break junk loose and clog up the line or inlet valve or filter. And sputter, cough, die usually sounds like fuel delivery.
My two cents
Andygears
My two cents
Andygears
-
- Member
- Posts: 256
- Joined: Mon Apr 09, 2012 7:38 pm
- Bikes: '02 Fatboy, '47 Knuckle, '52Pan
- Has thanked: 60 times
- Been thanked: 11 times
Re: won't start
I rechecked the points and found they closed up they were at .008,I reset them at .022 made no difference in trying to start, set timing mark in timing window, front piston up, then checked my points and realized somehow my timer jumped a tooth, points were off about 90 degrees, pulled the timer and reset it, the engine start and runs rough like its running out of fuel but conks out immediately, I was thinking one of the cam cover bushings might have disintegrated causing it to jump timing.
-
- Site sponsor
- Senior Member
- Posts: 1922
- Joined: Fri Jul 01, 2011 8:43 pm
- Bikes: 1969 FLF
1937 EL
1940 U - Location: san diego
- Has thanked: 1478 times
- Been thanked: 243 times
Re: won't start
Wow, that does not read promising at all, but on these pups it's all doable.
white1j0 wrote: ↑Sun Sep 23, 2018 2:11 pm I rechecked the points and found they closed up they were at .008,I reset them at .022 made no difference in trying to start, set timing mark in timing window, front piston up, then checked my points and realized somehow my timer jumped a tooth, points were off about 90 degrees, pulled the timer and reset it, the engine start and runs rough like its running out of fuel but conks out immediately, I was thinking one of the cam cover bushings might have disintegrated causing it to jump timing.
-
- Moderator
- Senior Member
- Posts: 8404
- Joined: Sat Nov 15, 2008 4:09 am
- Bikes: Multiple H-D, Ducati, BMW, Triumph, BSA,...
- Has thanked: 481 times
- Been thanked: 2954 times
Re: won't start
I think you screwed up your timing. Make sure the timing mark is front cylinder on compression stroke. The piston is up twice per cycle so just checking the piston position is not the way to tell. Make sure the mark comes into the window just after the intake pushrod closes. Timers don't jump teeth. The only thing would be if the pin sheared on the gear, but that is extremely rare. And a bushing disintegrating would be a first.
-
- Site sponsor
- Senior Member
- Posts: 1922
- Joined: Fri Jul 01, 2011 8:43 pm
- Bikes: 1969 FLF
1937 EL
1940 U - Location: san diego
- Has thanked: 1478 times
- Been thanked: 243 times
Re: won't start
What was written previously has validity, this is what I found one time in the cam chest cavity..
-
- Member
- Posts: 256
- Joined: Mon Apr 09, 2012 7:38 pm
- Bikes: '02 Fatboy, '47 Knuckle, '52Pan
- Has thanked: 60 times
- Been thanked: 11 times
Re: won't start
Rechecked everything, Front piston about 1/2" tdc intake / exhaust valves closed, timer mark just coming in window, points just getting ready to break.RUBONE wrote: ↑Sun Sep 23, 2018 3:55 pm I think you screwed up your timing. Make sure the timing mark is front cylinder on compression stroke. The piston is up twice per cycle so just checking the piston position is not the way to tell. Make sure the mark comes into the window just after the intake pushrod closes. Timers don't jump teeth. The only thing would be if the pin sheared on the gear, but that is extremely rare. And a bushing disintegrating would be a first.
-
- Member
- Posts: 256
- Joined: Mon Apr 09, 2012 7:38 pm
- Bikes: '02 Fatboy, '47 Knuckle, '52Pan
- Has thanked: 60 times
- Been thanked: 11 times
Re: won't start
Points are working fine, changed the condenser with a new Blue Streak I had laying around, pulled the cam cover everything is as new, starting to think its the coil, what are the signs of a bad coil ???,
-
- Senior Member
- Posts: 1407
- Joined: Tue Feb 05, 2013 12:25 am
- Bikes: 1950 panhead, 1999 FLHTCI, 1987 FLHTC custom
- Location: Daytona Beach
- Has thanked: 447 times
- Been thanked: 651 times
Re: won't start
So it will now start but run very rough? How do the plugs look? Black, wet or dry, white, light brown.? I still think fuel delivery but maybe plug wires? Is it running rough...missing randomly or really weak on one cylinder rough, check for difference in temp. Between the cylinders. Or running rough from extra rich, float and/or needle sticking, or rubber tipped inlet needle disconnected from needle body causing intermittent lean.
Picture of the spark plugs please.
Andygears
Picture of the spark plugs please.
Andygears
-
- Member
- Posts: 256
- Joined: Mon Apr 09, 2012 7:38 pm
- Bikes: '02 Fatboy, '47 Knuckle, '52Pan
- Has thanked: 60 times
- Been thanked: 11 times
Re: won't start
Does not start, just backfires through the carb, plugs are burning just a slight bit rich. Going to switch coils from my other '47 today and see if that's the problem.Andygears wrote: ↑Tue Sep 25, 2018 12:08 am So it will now start but run very rough? How do the plugs look? Black, wet or dry, white, light brown.? I still think fuel delivery but maybe plug wires? Is it running rough...missing randomly or really weak on one cylinder rough, check for difference in temp. Between the cylinders. Or running rough from extra rich, float and/or needle sticking, or rubber tipped inlet needle disconnected from needle body causing intermittent lean.
Picture of the spark plugs please.
Andygears
-
- Member
- Posts: 74
- Joined: Fri Sep 22, 2017 2:33 pm
- Bikes: 1984 FXE, 2002 883R
- Location: Chicagoland
- Has thanked: 17 times
- Been thanked: 26 times
Re: won't start
A bad coil will have difficulty producing a spark under cylinder compression but will show a spark with the plug out of the cylinder. If you have a inductive timing light you can use it to see if the plug is firing when it's installed, a bad coil won't cause the timing light to flash.