running rough

Well the head is off !! but I have made a right royal mess of it, followed the book and advise, released the head bolts gradually in correct order, lifted out the bolts, laid them all in order etc, removed the cam shaft caps, labeled and put in order, all ok so far !! left the small cap at front and the rear plate on and gently lifted the complete cam and carrier off the head, not noticed by me until to late was that 6 of the tappets and shims lifted with it, and then dropped off !! net result I had 6 tappets and 6 shims rolling about all over the garage floor, so I now have no idea which was on which.

Regards Steve.
All may not be lost, measure them and see what the differences are. If its only a few thou you can put them back anywhere, you only need something to give you a benchmark figure.
 
Fortunately you have one shim per tappet so just put them away till everything is machined up and ready to go together. You can then mix and match to get your numbers correct. Once you machine or replace the valves the numbers will be different anyway and if you regrind the cam and/or tappets they will be like new anyway.
 
thanks for that, you have both made me feel a bit better about the situation, measured the shims last night, they range from 10.21 to 10.62 so quite a difference across the range.

regards Steve.
 
now got my head back and the manifold should be back any day now,

one question i have please, my cam and carrier are still together just as i removed them, the little plate at the back still attached and the small carrier plus locking tab in position, can i refit the cam and carrier in this state and torque down the head? or do i need to take off the little locking plate, so as i can rotate the cam as I tighten down the head bolts ( dont want to stress or damage the cam) after being refitted, and gaps measured do you remove the cam caps and fit the spacers in the same order as for removing the cam.

hope this makes sense

Regards Steve.
 
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Hey Steve, as long as the cam and the crankshaft are locked in EP position (both locked with their respective keys) you should be fine. Just make sure you tighten the head bolts in the prescribed order from the manual.

As an added precaution I tend to tighten the head bolts a little at a time in order so no part of the cam feels like it’s being unduly stressed.

I wouldn’t rotate the cam while tightening as there’s a chance you’ll drive a valve into a piston.
 
thanks for that, i will follow your advice, leave both the cam and crank locked up, tighten as per book and a little at a time, need to unlock cam to measure the gaps, then relock in position prior to removing the caps etc.

As i dropped nearly all my shims over the garage floor when stripping the head out, i will start with the smallest in the exhaust and largest in the inlets, they range from .404 to .419.
once again many thanks Steve.
 
Head back on, bearing in mind that i dropped most of the tappets and shims when i stripped it out, and have had all the valves and seats lapped in, my measurements are all over the place, main question here is that my smallest feeler in 0.005 which will not pass under 3,4,6,7,8, thus the correct reading could be any where from 0.005 to 0.

what to do now? regards Steve
 
Head back on, bearing in mind that i dropped most of the tappets and shims when i stripped it out, and have had all the valves and seats lapped in, my measurements are all over the place, main question here is that my smallest feeler in 0.005 which will not pass under 3,4,6,7,8, thus the correct reading could be any where from 0.005 to 0.

what to do now? regards Steve
Did you make a note of where you placed the shims? Are the other valves massively wide on the gaps? I’d look at the list of available shims and see if you can swap them around enough to get some readable gaps.

On the super tight gaps, can you at least rotate the followers with a magnet or something? If so you know you have at least a little gap. If you find they are stick fast my guess would be that the valve is under pressure from the cam and needs smaller shims still to get to something measurable.
 
Thanks for that super quick reply, yes noted where shims were placed, gaps are 1 .007 2 .009 3 .005? 4 .005? 5 .011 6 .005? 7 .005? 8 .005?, as you can see its 3,4,6,7,8, that are the problem, took your advise and just checked them 3,4,7, will rotate easily, and 6,8, will not, so following on from here i will treat 6, and 8 as having no gap at all, and 3,4,7 as having a estimated gap of .003 ( got to start somewhere), been using your spread sheet to do the calculations, really good bit of kit.
Many thanks Steve.
 
Thanks for that super quick reply, yes noted where shims were placed, gaps are 1 .007 2 .009 3 .005? 4 .005? 5 .011 6 .005? 7 .005? 8 .005?, as you can see its 3,4,6,7,8, that are the problem, took your advise and just checked them 3,4,7, will rotate easily, and 6,8, will not, so following on from here i will treat 6, and 8 as having no gap at all, and 3,4,7 as having a estimated gap of .003 ( got to start somewhere), been using your spread sheet to do the calculations, really good bit of kit.
Many thanks Steve.
Sounds like a good plan!

Let us know how you get on.

Steven
 
Shims arrived yesterday, so off with the cam and fitted the revised shims with mixed results, we now have 1 009, 2 014, 3 009, 4013, 5 009, 6 012, 7 009, 8 002 approx ? so 4and 6 need slight adjustment, and 8 is still way out, but at least the tappet will rotate now and is not held solid, so must have been held quite tightly on previous check, i think this valve and seat maybe needed quite a lot of lapping in when the head was away.

New shims on order, and will try again soon,

Regards Steve.
 
Shims arrived and finally had time to fit, now have 009 and 014 across the board, every thing now refitted ( head all refurbished, and manifold repaired).
car runs ok but still have the annoying put put on idle, did a compression test and now have 175, 180, 175 ,175, not brilliant i know but a lot better than the original test, ( at least they are pretty even).

Still cannot balance the carbs, now found that the jet on the front carb is sticking again, the jet moves nice and freely up and down but when in use on the car it will not move back up( possible weak return spring) also the carb piston does not drop as it should, its very slow with no nice clonk, so off with the carbs for a strip down, now hopeful that if i can sort the carbs out i may at least have a working car, i will live with the low compressions for a while.
Regards Steve.
 
now got the jet working up and down as it should, just hope it wont start sticking when on the car like last time.

my carb pistons are still very slow to drop ( about 5 seconds) which must be to slow, any tips on how to sort them would be great.

regards Steve.
 
normally use 3 in 1 oil, but as carbs are off at the moment the drop is the same with oil / no oil, spring fitted or removed, suction seems very strong when moving piston by hand, the little breather hole is clear.
 
normally use 3 in 1 oil, but as carbs are off at the moment the drop is the same with oil / no oil, spring fitted or removed, suction seems very strong when moving piston by hand, the little breather hole is clear.
The damper only makes a real difference with the speed of lift for the pistons IIRC. So you notice it more if you stick your finger in the mouth of the carb and try and lift the piston. No oil = little resistance. Oil = resistance.
I tend to use 5w30 oil (as I have it for our modern cars) in the dash pots. That works well for temps here in New Jersey.
 
now got the jet working up and down as it should, just hope it wont start sticking when on the car like last time.

my carb pistons are still very slow to drop ( about 5 seconds) which must be to slow, any tips on how to sort them would be great.

regards Steve.
5 secs is a little slow. But you can vary that using different springs in the bell.
 
normally use 3 in 1 oil, but as carbs are off at the moment the drop is the same with oil / no oil, spring fitted or removed, suction seems very strong when moving piston by hand, the little breather hole is clear.
Does it drop quickly with a click as it hits the bridge without the damper fitted?
 
No, there is quite a bit of resistance when lifting the piston with or without oil or damper fitted, i suspected the springs and have a new pair of the correct, black/blue springs, there is no sound at all as it slowly hits the bridge. moving the piston in and out by hand, it feels as if there is far to much pressure/ suction present.
 
The piston & domes are matched in manufacturing, so it is worth trying swapping the pistons and testing again to see if that improves things. The last thing you want to do is change the springs.

Do they have spring loaded needles? I've seen that cause a lot of drag if the jet is not centred properly

Yours
Vern
 
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