Brumby timing issues

justincase41 · Post by **justincase41** » Sun Mar 23, 2014 6:37 pm

Howdy,
Having an issue sorting out the timing on the brumby. Basically motor has been turned over with out a dissy in so the timing is all out of whack.
I've put the motor at tdc, no 1 piston at tdc and markings on flywheel at 0. I've installed the dissy and placed the rotor cap end pointing at about 11 o'clock, which is on the trigger lug for the electronic ignition and right on number 1. I've then installed the cap and set the firing order at 1-3-4-2. I can't get the motor to fire. There is spark but just the typical popping and back firing associated with incorrect timing. So where have I gone wrong? The only other thing I can think is firing on wrong stroke.
Any advise would be helpful.

Silverbullet · Post by **Silverbullet** » Sun Mar 23, 2014 7:20 pm

Did you allow for the twist in the helical gears? By that I mean when you line your rotor up with #1 firing position before you slide it into the engine block you need to turn it an extra few degrees (clockwise I think) because when the teeth on the dizzy gear meshes with the helical gear on the crank as you slide it in it will turn the rotor arm. Hopefully that sentence made a little sense

It's easy to put the dizzy one tooth out if you aren't expecting it.

Good luck!

Subydoug · Post by **Subydoug** » Sun Mar 23, 2014 7:23 pm

First off, the firing order is 1-3-2-4. That should help you out. Second, if your not getting any firing at all, or your only getting the ocassional backfire, just try rotating your disty 180 degrees. You cant hurt anything. When putting them back in I usually just put the timing on about 8deg according to the flywheel markings and drop the disty back in aligning the rotor with #1. If it doesnt fire after a bit of cranking, flip it around and off she goes. Thinking back on it I dont think Ive ever got it right the first time

.

A timing light is very helpful to have on hand when she does start barking.

Regards

Doug

Post by **TOONGA** » Sun Mar 23, 2014 7:58 pm

as Doug has stated sounds like the dizzy is 180 degrees out, and the correct firing order helps heaps

A SB stated make sure you have the dizzy cranked back abit from how it should sit at TDC before it goes into the slot.

TOONGA

justincase41 · Post by **justincase41** » Sun Mar 23, 2014 8:32 pm

Oops, have been using the 1-3-2-4 firing order not the 1-3-4-2 I originally said. I have also been watching the positioning of the rotor after getting the dissy home as it goes rotate a bit as the teeth on the cam and dissy interlock. I will try setting it at 8 degrees if no joy I will then flip the dissy 180 degrees.
Thanks for the replies, stay tuned for results

RSR 555 · Post by **RSR 555** » Mon Mar 24, 2014 12:53 am

TDC happens twice on the crank and only once on the dizzy, so you could be 180 deg out on the dizzy, so the best way is to pull out #1 spark plug and turn over the engine (by hand) and feel for compression through the spark plug hole, then set the dizzy up. Just remember to watch the rotor button for rotation whilst you're turning the engine over to find TDC on compression stroke. Also, I'm pretty sure it's marked on the block but #1 is drivers front and #3 is drivers rear. Sorry if it sounds crazy but I've had to tell a few people this over the years.