Cam Sprocket locating pin nuts missing!

[STypeR]

The rocker covers are only temporary sitting on as I have focused on plumbing up all the hoses in the engine bay first and I have just noticed I am missing the two cam sprocket locating pin nuts!
Its been a while since I dropped the engine in and I cannot remember having missed these!
Plus the LH chain guide support bracket has not lined up too well..
Not sure if it is a standard nut as it looks like it has no thread on the Rimmers site?
Any advice on fitting would be much appreciated.
Thanks, John

[steve.n]

John, if you mean the one in the centre to temporarily hold the cam sprocket I think the ROM suggests temporary use of a camshaft cap nut. Could be wrong tho.
Not sure about the chain guide.
Steve

[len]

i agree with Steve, it all looks correct
Len

[mole42]

Nuts are not required!
You do need the sprocket bolt tab washers though. part 154161

[STypeR]

Thanks Gents for the reassurance. You are right, the nuts are to be removed from the support brackets when the engine is to be operational. It looks like a nut is to be placed here during engine repairs, cam removal, maintenance etc.
Learn something new every day!

[MandM]

As mole said Do not forget the locking tabs for cam bolts,or it could end badly.

[len]

Just as a bit of further info on the lock tab...I was advised to fit longer cam sprocket bolts and to fit a nylon lock nut...as added security.
len

[flying farmer]

The threadless nut shown on the Rimmers site is a press fit onto the centre pin.
It is there to stop the pin falling out of the sprocket when it is removed, and also gives something to tighten the nut against if the sprocket support bracket is being used to hold everything in place for cam removal when re-shimming valve clearances etc.
Without the threadless nut in place the sprocket would probably wobble enough on the pin to allow the chain tensioner to click up which would necessitate a front end strip down to reset the tensioners.
Neil

[STypeR]

Nuts are not required!
You do need the sprocket bolt tab washers though. part 154161

Thanks for the replies gents.
I do have those tabs but my engine assembly expert had decided against these and placed a machine washer and a lock washer instead (not as obvious in my photos). I notice that in the ROM and Parts Catalogue its just the bolts and the tab; no machine washer or lock washer. Has to be more reliable this way so I think I will fit them.
Is there anything wrong in leaving the lock washers with the tabs?

[mole42]

A spring lock washer can only work if it bears directly on the nut and the part that it is holding. Putting a plain washer between the parts means the lock washer cannot work effectively.
A spring washer is good for static loads but the sprocket bolts on a camshaft are subject to shock loads, which is why the engine designers used tab washers. If it were an aero engine, they’d have been wire locked as well!

[STypeR]

So I assume I need to therefore 'bolt up' the chain guide support brackets first before I start to loosen the sprocket bolts to change over to the tabs?

[flying farmer]

Best idea would be to undo one bolt, refit it with the lock tab in place leaving it loose enough to swing round under the other bolt when you have removed that one.

This will prevent the sprocket popping off the cam while you do the job.

Neil

[STypeR]

Yes I started doing that one bolt Neil but chickened out 3/4 of the way out as I did not think the other bolt would hold the sprocket in place....

[mole42]

One bolt will hold, so long as you don’t start the engine!

[STypeR]

Took me a while but I did fit the tabs. Removed the bolts and I noticed the machine washers were very tight on the bolt. This was keeping the lock washer in its locked position whether it was torqued up or not! So I am very glad this was done!