3.4 how to time but no timing marks?

[luke70]

hi folks hope you can help, currently trying to get my Jaguar powered replica to run BUT cant find any sort of timing marks as described in the Haynes for XJ6.
As far as I am aware it is a 3.4 from mid 1970, running a pair of 13/4 SUs. I have also fitted an electronic dizzy but am at a loss as how to time it properly. I cant find any marks on the main crank pully or on the one for the water pump and dynamo.

Any clues as to how best to do this and where do I find the engine number?

thanks
Luke

[piman]

Hello Luke,

I'll try and give you some guide, but as I'm a points person I have little experience of electronic distributors.

Firstly you need to get number one cylinder at TDC, on the compression stroke. the most sure way of doing this is to remove the cam covers and turn the engine so that it is on number six with the valves rocking, i.e. inlet just closing and the exhaust just opening. The cams when you are looking at them will be a broad vee on that cylinder. There are other methods but the above, although slightly laborious, is certain.

You next will need to ensure the distributor is set so that the rotor arm is feeding the number one plug. (Which should have just fired at TDC) If you are in that position, it should only take a small rotation of the distributor to get it to fire, a certain amount of trial and error. Once running slowly move the distributor until you get a reasonable idle, which may take a little time as the engine warms up.

As the best way of setting optimum timing is by road testing (the modern fuel being different than when the car was built so the 'book' figure may not be the best), take it for a run and advance the timing until it pinks then just back of a shade. Obviously, if it pinks as you set it then retard until it no longer pinks, just.

Alec

P.S. The engine number on a Mk 2 anyway is on the right hand side of the block above the oil filter and on the front of the cylinder head casting, I expect the XJ 6 will be the same?

[luke70]

Thanks for the reply, currently "having a go"..
used a dial gauge to find TDC and made a mark on damper (also had to make a pointer as it's missing)
Checked inside new Electronic dizzy that at this point Hall effect and tooth on the cog for rotor arm matched up with lead no1
Then adjusted for about 8 degrees.

currently having a sausage sandwich and will return to the garage in a minute.
BUT
had a carb leak via bellmouth, after new needle valve diaphragm and adjusting the float level the leak has stopped but now Either shes hissing and spitting back like mad or if I drop the needle revving like mad.

any suggestions?

[luke70]

Needle high adjusted on front carb and butterflies sync'd and the jobs a good un! Timing looks and sounds pretty good, will take her for a run and see how she goes.

thanks for the input