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Tips
Tips

Adjusting Valve Clearance

1) Remove valve cover
2) Remove all plugs
3) Put gearbox in neutral, use starter solenoid to employ 'Rule of 13;' e.g. to adjust #1 valve get #12 valve as close to rock (fully open) as possible
4) Put car in fourth and push car forward/back as necessary to get #12 at rock (rock is probably 20deg or so; close is good enough)
5) Repeat steps# 3-4 for the remaining valves
Hey Bob,
Seems like I have seen you can adjust the BN2's valves when cold or hot. What do you recommend ? Going to have a buddy help me
adjust them on my 100M tomorrow.
Thanks,
Mike
 
Room temperature ;)

JK. I don't think it's critical; I remember adjusting mine cold, then checking hot--or the other way around--and I think it was less than a thou of difference. Presumably, adjusting hot would give a larger gap when the everything cools down but, since valves, rockers, pushrods all get hot and cold I think they offset. If you have an aftermarket cam you'd want to set per the manufacturer's specs; IIRC my DWR1 cam sheet calls for 0.015" on the exhaust valve, which is a bit larger than a stock BJ8 cam. Anybody seen a big difference hot or cold?

Of course, for a 4-cyl you use the 'Rule of 9.'
 
Thanks Bob ! It will have a half an hour to cool down some before we start so will just be warm by then !
 
Room temperature ;)

JK. I don't think it's critical; I remember adjusting mine cold, then checking hot--or the other way around--and I think it was less than a thou of difference. Presumably, adjusting hot would give a larger gap when the everything cools down but, since valves, rockers, pushrods all get hot and cold I think they offset. If you have an aftermarket cam you'd want to set per the manufacturer's specs; IIRC my DWR1 cam sheet calls for 0.015" on the exhaust valve, which is a bit larger than a stock BJ8 cam. Anybody seen a big difference hot or cold?

Of course, for a 4-cyl you use the 'Rule of 9.'
Bob - Please check your email and also your Private Messages (Look at the envelope icon above on the right of the page). I replied to your Private Message.
 
Is this order ok to use?
 

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I put the car in 3rd gear and put one hand on the top of the front tire and the second hand on the windshield post ..... then push with one hand and pull with the other ...... to roll the car forward ...... using the above sequence. Spark plugs out of course. It's very easy this way.
 
Thank you. That's what I did. Easy Peasy. I used the chart above so you can adjust two valves at a time.
 
Follow up on my latest saga ! Got them adjusted late last week and actually very minor adjustments needed. Took plugs
out, put in 4th gear, and easy to get done. End result was did eliminate what I thought was excessive noise.
 
From what I have read, the adjustment is a balance on how you drive the car. Too small of a gap and the valves don't stay closed long enough, too big of a gap and they stay closed too long.
 
My next project will be to replace the broken copper capillary tube for the distributor advance. Goes from the dizzy to the rear
carb and has broken off at that carb. Healey is running great and hesitated due to my "if it ain't broke don't fix it"!

But buddy who helped me - or, more correctly, I helped him adjust the valves - strongly believes that condition is not good long term. So
guess I'll be taking the rear carb off, fitting the new tube, and getting the advance working properly. Would help if I had hands
the size of my 6-year-old grand daughter instead of normal size for a 75 year old guy!
 
That's where I could use the 6 year old hands. Maybe can do without removing and much preferred to do it that way. Would sure
be hugely preferred as would not have to remove the cold air box, etc. I'll approach it that way and let all know the results !
 
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