June 7, 2015 at 6:30 pm #1705
Hi guys, I need to set up the dwell or linkage on a 1953 15 hp fastwin, when I turn the throttle the roller that rides on the "cam plate?"and is connected to the butterfly of the carb through linkage goes right off the end of that timing plate.June 7, 2015 at 6:57 pm #17754
The carb should just start to open when the roller hits the hash line on the brass cam. If not, loosen the screw on the cam, and pull it out some. If it carb butterfly starts to open too early, push the cam in.
Re tighten bolt and you are done!June 7, 2015 at 7:14 pm #17755
thanks, i’ll see if I can see that hash line!June 7, 2015 at 7:57 pm #17756
hmmm, I see what you mean to adjust the "throw" of that plate but it looks like the plate itself can’t be moved. somethings way out on the linkage and im thinking its the gear mesh on the throttle handle?
cam right off the roller , full throttle,
throttle full off "start position, no where near the hash marks,
throttle full on
throttle full off, start position, all they way to the end of the gear mesh
somethings not right,,,,
US Member - 2 Years
Topics: 38June 7, 2015 at 8:15 pm #17757
The gear mesh looks right. The plug wires don’t look properly clamped under the mag plate thoughJune 7, 2015 at 9:02 pm #17760
Your first pic, "cam right off the roller, full throttle", is incorrect The roller being off the skinny part of the cam would be a "less than idle" position. At idle, you should be near the skinny end of the cam, at full speed, near the fat end of the cam. Never off the cam, bearing on the ignition wires. Once you get near the skinny end of the cam, the roller no longer makes contact. It "floats" in the air until you advance the throttle enough for the roller to make first contact at the hash mark. Something is definitely wrong between the roller rubber and the carb throttle shaft in that linkage. Fix this problem first.
Later,I might work backwards for a second- put the roller near the end of the fat end of the cam, and work backwards to see what’s needed to make the "twist grip" indicate "fast".
Maybe something wonky at the rear of the engine under the mag plate with the vertical throttle shaft, and the curved brass arm under the mag plate.June 7, 2015 at 9:04 pm #17761
Looking at the motor, the bolt on the right (narrow end of cam) will have an oblong hole, so that it pivots in and out. Loosen that bolt, to adjust the cam.
Now, the gear mesh seems ok.
The hash marks you see in the pic are not the one I was referring to. Those are for setting the points. The hash mark will be on the brass cam itself. When that roller hits it, the carb butterfly should start to open.June 7, 2015 at 9:05 pm #17762
When you put it in forward gear, and advance throttle to FULL, is the roller sitting on the end of the fat side of the cam>?
Topics: 13June 7, 2015 at 9:25 pm #17764
You need to be looking at the top side of the brass plate, not the side or bottom. Looking from the top and you will see a mark embossed into the brass plate. About 1/3 of the way from the skinny end. It’s like a slot indented into the plate.June 7, 2015 at 9:27 pm #17765
Maybe some pics of the vertical throttle shaft top and the linkage there, and also a port side pic of the carburetor throttle shaft/link/arms.
With the roller bearing on the ignition wires, it seems like the carburetor throttle plate would be jammed wide open before you could get all the way up the ramp to the full throttle position near the fat end of the cam.June 7, 2015 at 9:36 pm #17766
ok, I had it as* backwards! I think it might be fine, other than the roller going off the end of the cam in the stop position,
pulled the intake airhorn off to verify the butterfly. and right, in neutral throttle is limited, ok , seems good, thought it would run away for my upcoming first start , Cliff,June 7, 2015 at 9:38 pm #17767
hey wiscoboater, ok, ill check the cam mark in a bit,,, and get some photos of the carb linkage Theodore,,,, better safe than sorry,June 7, 2015 at 10:08 pm #17769
FULL THROTTLE IN FORWARD GEAR
SLOW THROTTLE HANDLE POSTION
STOP POSITIONJune 7, 2015 at 10:29 pm #17772
The carb throttle shaft shouldn’t start to move until the roller hits the hash on the brass cam. It still seems to me that the roller is bumping along the ignition wires, and bearing on all the cam, from the skinny end on up to the hash.
I’m not familiar with the ’54. On my ’57’s and ’58’s, the first time the roller touches the cam, and the throttle shaft starts to move, is at the hash.
As someone else said, the wires shouldn’t be hanging out there like that.
- You must be logged in to reply to this topic.