Timing question on 84 Big Red

[hfd410]

When crankshaft is indicating T my camshaft O mark is straight up top at indicator mark as manual describes. I rotate crank to T again and my cam O mark is straight down 180 from last position. My question is does the cam rotate once for every two rotations of crank? Also does anyone know
what the "index mark" looks like on the pulse generator (the part with the little cams and springs). I found the punch mark on the rotor but wasnt sure what the index mark looked like. It is possible to get the rotor 180 out. There is a small o stamped on it that can line up with the punch mark. If you install it 180 the other way there isnt any kind of mark. Thanks

[hoosierlogger]

Yes you can have it 180 out. The cam does turn twice per crankshaft revolution. The mark on the advance plate looks just like the mark on the rotor. The advance plate will only go on the cam one way, but the rotor can go on the plate 2 ways. One of which is incorrect. It should line up with the stamped o.

[hfd410]

Yeah the rotor has a punch mark that is very obvious, however the advance plate mark isnt as evident. But there is an o stamped on it that can line up with the stamped mark on the rotor. Im pretty sure I have it right because I cant find any other mark on the advance plate. Getting frustrated, I have good spark and she wont even try to start with starter fluid. All components check out good with ohm meter, good compression, cleaned carb.

[hoosierlogger]

Your timing chain is probably stretched. Move it 1 tooth to the left. If that dont do it, go 1 tooth to the right. Thats what was going on with my 200X. I was ready to pull my hair out. Now I need to tear it back down to put in a new chain. I never thought about it being bad when I put the top end back on.

[WilliamJ]

A cam tooth either way won’t prevent the motor from running (as long as your valves and pistons don’t hit each other!) Also your ignition timing can be a fair way out and it will still run (20 or 30 degrees).

The best way to be sure if your cam timing is correct is to get the piston to TDC and physically check that it is there. The marks are usually good but eyeballing the the thing is more certain. Pencil in the plug hole while you slowly turn the engine is close enough. Then look at the camshaft and valves. Valves should both be fully closed with clearance at TDC - the lobes on the cam will both be pointing down equally. Now check the pulse generator is at the firing point and with spark and new fuel (squirt a small amount in) a new plug and you should be in business. Good luck.
Bill

[hoosierlogger]

A cam tooth either way won’t prevent the motor from running (as long as your valves and pistons don’t hit each other!)

BS!! My 200x wouldnt start with all of the marks lined up perfectly and thats what caused it. I moved it 1 tooth and it started on the first kick.

[tri again]

aaaah, the old chevy trick.
My uncle did that to my amazement.
Either didn't have $ for or couldn't find a timing chain so he just set it back one tooth.
and the crank AND cam marks lined up way better.

Ran like new.

but I would think the poor trike would at least spit, sputter, backfire or something with spark and fuel.
Heck, an open pit fire will do SOMEthing with fuel and sparks.
Then again, I lost count of the trikes I have that are 'dead'.

[WilliamJ]

BS!! My 200x wouldnt start with all of the marks lined up perfectly and thats what caused it. I moved it 1 tooth and it started on the first kick.

I don’t write BS and there is no need to be offensive.
I have been building road and race engines for 30 years and I have made a lot of mistakes and had to put them right. I have never, repeat never had an engine refuse to start because the cam was one tooth out. You may believe you have had that happen to you but I suspect there was something else as well. Wet plug, no fuel etc.
A high compression race engine with wild camshaft will start, run and idle with 45 degrees of fixed advance from cold. It will also start with the camshaft wildly mis-timed and as long as the valves don’t hit each other or the piston, it will often run smoothly. Won’t make any power though.
Bill

[hoosierlogger]

I don’t write BS and there is no need to be offensive.
I have been building road and race engines for 30 years and I have made a lot of mistakes and had to put them right. I have never, repeat never had an engine refuse to start because the cam was one tooth out. You may believe you have had that happen to you but I suspect there was something else as well. Wet plug, no fuel etc.
A high compression race engine with wild camshaft will start, run and idle with 45 degrees of fixed advance from cold. It will also start with the camshaft wildly mis-timed and as long as the valves don’t hit each other or the piston, it will often run smoothly. Won’t make any power though.
Bill

Wasn't trying to be offensive, but that is the case on my 200X. The cam chain was stretched. I moved it 1 tooth and it fired the next kick after the correction was made. If you dont believe me you or anyone else on this board are more than welcome to look at the cam sprocket. Believe it or not I am smart enough to make sure the gas is on and the plug is dry.