Club 80-90 Forums

Bouight a timing gun at the wknd and attepted to check my timing. All going well removed the vacum pipe and found my two timing marks on the pulley. BUT when I checked my marks they are at the bottom of the pulley when using the strobe when they should be seen at the top, the timing mark should be inline with the slit in the crank cases, it is but its at the bottom. The engine runs fine, has some one put or refitted some thing 180 degrees out in the past. The idle is around 1000rpm when checking and the disi is the right place as per the photos and not twisted round. Hope some one can help.

Pete

you sure you have the strobe on plug 1 ??

When stood looking into the engine bay..
No 1 is the plug on the right towards the front of the van

Does the rotor arm align with the TDC mark on the dizzy body? could be that someone has installed the dizzy drive wrong...

Cheers, as I'm looking down on the engine I was hooking onto the cable from spark plug situated left nearest me, have I commited a school boy error!

standing with your knees by the numberplate, looking down, number 1 is righthand side, furthest from you.

Hi, that picture explains all well, hope it worked out. I am in the process of doing th same and wondered , after taking off the vac lne, blocking it and running warm at around 900rpm etc are you aligning the v shaped TDC notch on the side of the pulley nearest the engine block with the crack in the crankcase or the 'dimple' on the outside of the pulley (nearest rear of vehicle) which i assume is at 5degrees BTDC.....I ask cos i'm wondering .....? good luck and thanks. Tim

A Haynes manual is usefull...


The "U" is TDC, the "V" is 5 degrees BTDC.. I usually run slightly more than 5 on the DG..

toomanytoys wrote: I usually run slightly more than 5 on the DG..

Oh yes?
to what advantage Simon.

I find it runs a bit better... its such a low CR...

Not sure how relevant this is with a T25 but on bugs I always set timing with the gun then shifted dizzy, advancing till it just doesn't pink on the road or else (memory going a bit) 29 degrees max advance when revved up. Always seemed the optimum setting. The timing mark with a gun is a good basis but some engines seem to run slightly better either side of of the static mark. Yet to come across two engines that ran exactly the same to be honest although they may well have done when new so I think toomanytoys makes a good point here.

toomanytoys wrote:A Haynes manual is usefull...


The "U" is TDC, the "V" is 5 degrees BTDC.. I usually run slightly more than 5 on the DG..

Thanks for this- i know it may sound stupid but just to be sure it is the V shaped notch nearest the block to the right of the dimple that needs to be set by strobe to align with crack in crankcase. Why/ what is the round dimple on the outer rim therefor?? ta.

Tim

waltraud wrote: what is the round dimple on the outer rim therefor?? ta.

Tim

thats to show TDC on compression stroke No 1 cyl
you set to BTDC V notch

Thanks Rev, very helpful.

Tim