Valve timing and manual confusion

J

johnsimister

Active Member
I'm reaching the point when I shall be reassembling my now-2200 engine, and I am puzzled by the wording in the factory workshop manual.

It says, to quote, 'On late models [like mine] the timing hole in the flywheel has been repositioned, so that when the flywheel locking peg is inserted the EP mark no longer lines up exactly with the timing pointer. This has been done for assembly purposes and is a design feature to ensure that the timing is correct after the timing chains have been fitted and the engine run under power; when all the backlash in the timing mechanism is taken up. It means that the procedure for valve timing during assembly of chains and chainwheels and valve checking after operational running now differ.'

The manual then describes how to check and re-set the valve timing, instructing us to position the EP mark in line with the pointer and making no mention of the locking key which, for the reason mentioned above, of course wouldn't fit anyway. Presumably this is the method for engines which have already been run and whose timing chains have been under load.

I'm building the engine from scratch, with new chains and tensioners. It seems that I should set the timing by using the locking peg, as implied in the first paragraph above. Am I right?

Many thanks for any advice.

John
 
johnsimister said:
I'm building the engine from scratch, with new chains and tensioners. It seems that I should set the timing by using the locking peg, as implied in the first paragraph above. Am I right?
Click to expand...

That's how I've done them. With new chains and gears on a lot of occasions there isn't even enough slack in the chains to allow the tensioners to pop out and start self adjusting, so after a few miles they need a little helping hand to get going.
 
The way I read the manual , in both cases the pin is inserted , the note is just to advise that the EP mark will not align exactly on later models.
 
The EP mark helps you to find the locking point. Without it, you wouldn't know where to insert the pin.
As i understand it, in the later models, they drilled the hole in the flywheel in a slightly different place, but they did not bother to also move the EP mark.
 
As mentioned above , the holes for the pins could actually be set anywhere, as long as all the wheels line up at that point, but to make it easy there were originally set at the EP point in the system so you could set it to put the pins in . The fact they moved it slightly on later versions is really immaterial. but the EP mark should still be at maximum opening of the exhaust valve.
 
roverp480 said:
but to make it easy there were originally set at the EP point in the system so you could set it to put the pins in .
Click to expand...

The reason it was set at EP was that's the point the cam should be set at to remove the head.

To the OP, I'd say don't over-think this, use the pegs to align the crank and cam and fit your chains to suit. once it's all together turn the engine over by hand a few times and then recheck that both pins still fit. In use the chain will stretch and that will retard the cam timing, but unless you keep altering it on the vernier to compensate that will always happen, and I've never had engines that were so far out in service that I couldn't get them pegged up if I needed to, but when removing heads I only ever pegged up the cam anyway. I doubt that you will notice any loss of performance due to any possible alteration.
 
That's what I'll do, and I suspect/hope that if I check the valve timing after the engine has run for a bit I will find the EP mark in perfect line with the pointer. Which I surmise is the condition that Rover was aiming for with that information in the manual.

Many thanks for all advice.
 
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