Are these worn out? - Morris Minor Rockers
Discussion
Hi all, probably a stupid question but i need a quick answer as to whether these rockers are shagged or not?
I am trying to do a service on my girlfriends morris minor, and the final bit is to adjust the valve rocker clearances. Once in the correct positions the clearances all seemed a little tight, but on firther inspection the rocker pads seem to be in an awkward shape which makes the feeler guage open the clearance more than it should. I know this hardly makes sense but hopefully the pictures will explain better:
Any ideas?
I am trying to do a service on my girlfriends morris minor, and the final bit is to adjust the valve rocker clearances. Once in the correct positions the clearances all seemed a little tight, but on firther inspection the rocker pads seem to be in an awkward shape which makes the feeler guage open the clearance more than it should. I know this hardly makes sense but hopefully the pictures will explain better:
Any ideas?
lewis s said:
Hi all, probably a stupid question but i need a quick answer as to whether these rockers are shagged or not?
I am trying to do a service on my girlfriends morris minor, and the final bit is to adjust the valve rocker clearances. Once in the correct positions the clearances all seemed a little tight, but on firther inspection the rocker pads seem to be in an awkward shape which makes the feeler guage open the clearance more than it should. I know this hardly makes sense but hopefully the pictures will explain better:
Any ideas?
not sure i get what you mean there mate. if the clearance is too tight for the feeler gauge (assuming your using the right thickness feeler gauge for that particular engine), then you need to adjust them.I am trying to do a service on my girlfriends morris minor, and the final bit is to adjust the valve rocker clearances. Once in the correct positions the clearances all seemed a little tight, but on firther inspection the rocker pads seem to be in an awkward shape which makes the feeler guage open the clearance more than it should. I know this hardly makes sense but hopefully the pictures will explain better:
Any ideas?
if thats not what you meant please try to explain more
Ok i think i may have made a slight error in my previous attempt. I have now just put the feeler gauge just between the contact patches and not right the way through, and this seems a little better. Is this the correct method of doing so, the Haynes manual seems a little brief on the matter?
Also i keep seeing conflicting articles on what gap they should be at. The Haynes manual say 0.012", but sources on the internet say 0.010" and only 0.012" on high lift cam models. Is it better the gap be too large or too small?
I apologise for the onslaught of questions
Also i keep seeing conflicting articles on what gap they should be at. The Haynes manual say 0.012", but sources on the internet say 0.010" and only 0.012" on high lift cam models. Is it better the gap be too large or too small?
I apologise for the onslaught of questions
dan19evans said:
lewis s said:
Hi all, probably a stupid question but i need a quick answer as to whether these rockers are shagged or not?
I am trying to do a service on my girlfriends morris minor, and the final bit is to adjust the valve rocker clearances. Once in the correct positions the clearances all seemed a little tight, but on firther inspection the rocker pads seem to be in an awkward shape which makes the feeler guage open the clearance more than it should. I know this hardly makes sense but hopefully the pictures will explain better:
Any ideas?
not sure i get what you mean there mate. if the clearance is too tight for the feeler gauge (assuming your using the right thickness feeler gauge for that particular engine), then you need to adjust them.I am trying to do a service on my girlfriends morris minor, and the final bit is to adjust the valve rocker clearances. Once in the correct positions the clearances all seemed a little tight, but on firther inspection the rocker pads seem to be in an awkward shape which makes the feeler guage open the clearance more than it should. I know this hardly makes sense but hopefully the pictures will explain better:
Any ideas?
if thats not what you meant please try to explain more
Pumaracing said:
Yes they're completely shagged. Best way to adjust those, other than replacing them, is with a dial gauge so you can accurately measure the 12 thou clearance you need. Feeler gauges are no use in a situation like that.
Thanks for the honest reply 
I have a spare engine in the back garden so i will see if they are any better
Old rockers like that will most likely be worn into a cup shape which the valve stem is then sitting in. Your 'feeler right through' method is bridging across the 'cup' and giving a false reading.
The longer term answer is to remove the rockers and rub them down on a grinding stone to remove the cup leaving a convex surface.
The short term answer is as advised to use a dial gauge to set the clearances.
Don't worry too much about the 2 thou difference as you would need to be pretty competent with feelers to achieve that repeatability.
Steve
The longer term answer is to remove the rockers and rub them down on a grinding stone to remove the cup leaving a convex surface.
The short term answer is as advised to use a dial gauge to set the clearances.
Don't worry too much about the 2 thou difference as you would need to be pretty competent with feelers to achieve that repeatability.
Steve
Mini 1000cc Rockers
Full roller assembly
ETA: Pressed type (Same as yours)
Full roller assembly
ETA: Pressed type (Same as yours)
Edited by annodomini2 on Tuesday 8th June 13:29
The only bugger is that to repace them, you have to undo the head rear bolts to remove the pillars. In doing this may cause HG problems ( unless the head is seized in place !!!). You 'might' be able to undo the rockers adjustments all the way and see if the rocker shaft will slide out and all the rockers and springs bounce all over the place by removing the split washer on the shaft and washers, being the engine is in line, although worn rockers, usually eat into the shaft underneath and may get stuck getting the shaft out. You could just get the A+ rockers, which are steel type and not cast style. They have a slightly larger pad area on them but that means swopping the set completely and might as well do a decoke and new HG at the same time. Only takes 30 mins to take a head off an A series anyway, as long as it all undoes.
Clearance is 12 thou, not 10. Well that's the figure I used to use, gleaned from the Haynes manual which unlike modern Haynes manuals was basically a reprint of the factory manual in a different cover, and so pretty trustworthy.
Once you've done 'em enough times you can do it by feel without the need for instruments
Once you've done 'em enough times you can do it by feel without the need for instruments
Justin S said:
The only bugger is that to repace them, you have to undo the head rear bolts to remove the pillars. In doing this may cause HG problems ( unless the head is seized in place !!!). You 'might' be able to undo the rockers adjustments all the way and see if the rocker shaft will slide out and all the rockers and springs bounce all over the place by removing the split washer on the shaft and washers, being the engine is in line, although worn rockers, usually eat into the shaft underneath and may get stuck getting the shaft out. You could just get the A+ rockers, which are steel type and not cast style. They have a slightly larger pad area on them but that means swopping the set completely and might as well do a decoke and new HG at the same time. Only takes 30 mins to take a head off an A series anyway, as long as it all undoes.
The likelyhood of any sort of gasket problems occuring on an old Cast Iron block/head is absolutely minimal IMHO.If the set in the garden are OK swap them over complete ,don't P**s about trying to extract the rocker shaft in situ,it will be far quicker to swap the complete assy.
As the next post says,a head gasket is a dead easy job on a MM,if a failure should occur then replace it but I've never needed to.
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