Club 80-90 Forums

Hi there, not been on here for a while but here goes!
Having issues getn the timing sorted out, went to tighten the Dizzy clamp and the bolt snapped, took the dizzy off and had bent the clamp somehow so it was flattened out bc it was preventing the dizzy pushing into place, but my problem now is this.....
When turning the Flywheel clockwise the TDC marks on the Flywheel are at the bottom when the piston is uppermost (tdc) in the chamber?!
I thought the tdc marks on the flywheel denote the piston being at the top when I'm looking into the barrel using a torch but, when the piston is at the top of the barrel looking in it the flywheel marks are at the bottom of the case?
Could someone have removed the flywheel and put it on 180deg out? Is that possible bc I think there's a woodruff key that prevents it from being fitted incorrectly thus making it difficult to refit improperly unless the woodruff key was lost and flywheel put back on 180out without the key in place? unable to sort the timing out properly, it's way down on power after I asked a garage to adjust the timing and mixture bc it was running rich, hasn't run the same since then so could they have put the flywheel on 180 out but why would they even remove the wheel unless they didn't know what they're doing, only just noticed today the position of the piston in respect of the tdc marks being at the bottom of the case instead of the top.... Help please, it's our daily driver and supposed to be goin to Volksfling in 2weeks.

Flywheel and front pully cant easily be put on wrong as they have a pin and woodruf key
are you sure you are looking at no1 cylinder, right towards cab as you view engine from rear

Only two barrels will be at the top

Yep, definitely looking inside No1 cylinder, removed the air box so I cld look in the plug hole, can see the piston moving up n down, if I keep turning (clockwise) I see the piston go thru it's cycle but at no point does the tdc marks on the pulley coordinate with the piston being at the top of the chamber, the marks are at the bottom of the wheel when the piston appears to be at tdc, and when the marks are aligned with the crankcase join the piston is at the bottom of the chamber?

Anyway flywheel on wrong would not do that the pulley would neec to be on wrong

both valves shut on the firing stroke should see the mark on top

Just looked at one of my spare engines and it has a slot opposite
my guess is its a replacement pulley which had no marks and somebody made them in tge wrong place

get it tdc and make new marks go from there

Could well be that someone has marked the wheel wrongly, it's why I'm thinking the wheel is upside down?! Il defo try the suggestion of making new marks at tdc bc it's throwing me off.
I did put it back how it was and it fired up, went for a run and it's the same as before, underpowered and revvy, if I floor it it almost coughs or backfires but ultimately gutless, if I remark it 180deg round and set the dizzy to the new mark as the No1 tdc I wonder if that'l sort it?
Il report my findings before the weekend is out, a mates got a proper gun to set timing and is over at the weekend,

Best not to just reference off the old mark
get a piece of wire in the plug hole and you should be able to see from the wire moving when the piston is at the top of the stroke, then make a u mark with a round file on the outer rim of the pulley, the timing mark is 5 degrees which equates to another mark 7mm around the circumference clockwise as you look at the pulley make this a v slot with a square file on the inner rim.

Or make a tipex mark on the pully at TDC No.1 (both valves closed)
Then another 7mm away clockwise
once checked with a timing gun make them permenant

kevtherev wrote:Or make a tipex mark on the pully at TDC No.1 (both valves closed)
Then another 7mm away clockwise
once checked with a timing gun make them permenant

I'd have thought its hard to see exactly when both valves are closed, may be wrong though

itchyfeet wrote:

kevtherev wrote:Or make a tipex mark on the pully at TDC No.1 (both valves closed)
Then another 7mm away clockwise
once checked with a timing gun make them permenant

I'd have thought its hard to see exactly when both valves are closed, may be wrong though

if you pop of the rocker cover this will help to make certain, I used to do this on F ORD engines, also if you put a thin screwdriver in the plug hole, as you rotate the engine you will see it rise then start to fall again, if you rock back and forward you will get it exactly at TDC . Obviously as Kev said, make sure its on the compression stroke not exhaust, hence why looking at the valves will help with this. This pic will help others when determining the cylinder numbering ( not obvious )



Thanks to Ghost123uk .

Thanks for all your advice on this, I have removed the air box thus making it possible to actually look into the barrel and watch the piston reach absolute tdc, il remove the rocker cover to make sure the valves are at their closed position to confirm compression stroke, I am 100% sure the marks on the pulley are 180deg out, why it's 180 out I don't know bc I've cranked it by hand 10 times and the tdc marks are always at the bottom? This has made me think someone put a new wheel on and marked it wrongly bc the piston is at the bottom when tdc marks are at tdc with the crankcase halves?!

itchyfeet wrote:

kevtherev wrote:Or make a tipex mark on the pully at TDC No.1 (both valves closed)
Then another 7mm away clockwise
once checked with a timing gun make them permenant

I'd have thought its hard to see exactly when both valves are closed, may be wrong though

No not wrong.
I just think with spurious timing marks, adding new ones requires the cover off and a degree of certainty.