Shim popped out to say hello! (A/S inlet cam)

[Stani1029]

well today was the day my car was started up, first turn as always she roared into life. a little noisy to start with but that soon went away once oil was pumped round the engine. but after about 30 seconds idling at 2000rpm the noise soon changed and i knew what had happened. now i dont understand how its happened as i done all the clearances to about 0.28mm after setting them to 0.30mm originally and see-ing the shim wanting to tiddly wink there way out. i managed to get the shim back and it seems the bucket has took the worst of the damage. now does anyone have any ideas what im doing wrong, should the clearances be less or more or should i just fit a standard cam again

 

[frank]

mine are set to the same 10 thou (.25mm) stani fwn dunno whats happening there

 

[Stani1029]

its always me lol considering the cams ok i might reduce the clearance that little bit more and try it out but if it happens again and the shim drops down the chain side (shim nearest the chain thats come out) i wont be amused also whats the chances of them taking a constant beating from me and holding up when 1 couldnt stay in on idle lol

 

[frank]

i suppose you could fit them both underneath and face the top of the buckets like ebb did, but spitout at 2k is very concerning eh

 

[Stani1029]

im not sure what i should do, im considering cleaning the shim/buckets and sticking them together? the sealer i use is tough stuff so there shouldnt be a problem with that it all comes down to if the cam is re-useable :down:

 

[frank]

i doubt if sealer would survive mate fwn here,s a bucket i,ve just ground the outer lip off, and i,m gonna fit a set to mine (for peace of mind lol)

 

[frank]

i,ve done you a set if you want them frodo :grinning:

 

[Stani1029]

Frodo lol only if its not been a big hassle mate afterall you helped me big time with my piston swapping :wasntme:

 

[frank]

np bagginses :grinning: i,ll get them in the post tomorrow

 

[baguete]

I think i will do a set too, just in case... :laugh:

But i was doing 7600rpm without problems (after having some issues at 7300rpm), was a slightly stuck bucket, after i changed the bucket it didnt happened again.

 

[frank]

mine are in, and sounding sweet stani :grinning: (and yours are en route)

 

[Stani1029]

nice frank, did you have to redo the clearances? and yours are en route too cannot wait!

 

[frank]

nice frank, did you have to redo the clearances? and yours are en route too cannot wait!

the clearances measured up the same mate, but 1 of the previous ones was only 6 thou (i rushed the job last time lol) and there was no base circle contact on that one, ie the gray coating from the regrind had,nt rubbed off.
so i set them all to 6 thou (.15mm) for a very sweet/quiet idle

 

[Stani1029]

so 0.15 is ok? i spent hours last time getting them to the haynes spec taking the cam in and out many times was a pain! :glare:

 

[frank]

lol, its a PITA job aint it stani i,ll let you know on the 6 thou situation, i had already tested it last time and the clearances opened up when the engine got hot, you would think that they would expand and close up , (maybe the alloy head expands more than the valve stem eh)
but these cams are pretty aggressive and quite tappety TBH

 

[Stani1029]

yeah i thought that anything below 0.25 would leave the valves open when hot and anything above the 0.33 would sound very tappety but i think i remember see-ing that when the engine is hot the clearances are more. so if you can let me know what you think ill copy you :grinning:

 

[baguete]

Does the bucket sits very high compared with before? Can they go downwards not completly straight and can be scratched (and the head too)?

 

[frank]

Does the bucket sits very high compared with before? Can they go downwards not completly straight and can be scratched (and the head too)?

thats why i posted the pic mate, you can see its fine :grinning: and i cant believe how much quieter it is now, i can sit at the lights with my window open and just hear a gentle burble at the back, and no "chick chick chick" any more
it just shows how aggressive those cams are, the way they smack the valves open and shut

 

[frank]

the CR engines use shimless buckets incidently, with probably a tophat/button shim over the valvestem for adjustment (one of pharte,s pics :wasntme

 

[will930]

i know that e-types have shims under the buckets which i guess would stop them from saying hello

 

[frank]

ahh, cheers will i just checked nissan4u and the CR,s have no shims but instead they have 69 different thickness buckets (no doubt more expensive to buy that the £6 shims fwn)

 

[Low Rider]

i know that e-types have shims under the buckets which i guess would stop them from saying hello

They do but they can still have problems with the lifters moving about when people use re-ground cams in them which have puny base circles. I've seen under bucket shims pop out before and make a real mess. The bigger problem with them though is the lifter guides coming loose in the head, but this is an easy fix with a set of guide retainers

 

[will930]

They do but they can still have problems with the lifters moving about when people use re-ground cams in them which have puny base circles. I've seen under bucket shims pop out before and make a real mess. The bigger problem with them though is the lifter guides coming loose in the head, but this is an easy fix with a set of guide retainers

well where i done some work we built one up full spec with custom cams valves etc and his engines are guarenteed for 10 years or 100,000 miles and they are raced alot so i guess it works lol

 

[Low Rider]

well where i done some work we built one up full spec with custom cams valves etc and his engines are guarenteed for 10 years or 100,000 miles and they are raced alot so i guess it works lol

Full spec to us is alloy block, 35/40 head, forged crank, carrillo rods, forged pistons, cams, ~£40k budget, but they don't last that long

Last one me and the old man built was a 3.8 block, big valve flowed head, wide blade rods, pressure cast pistons, Isky XM3 cams, lynx manifold and webbers. Not been on the dyno yet because the car has only just gone in for paint, but should go well we hope.

Anyhooo, this is a K11 forum, I should shut it with the Jag talk eh

 

[frank]

its in the general chat section anyway low rider lol :grinning:
we,ve done the red car,s inlet cam too today, and sprayed matt black on the lobes to check for base circle skidmarks/contact lol so i have 2 CG swiss watches now

 

[baguete]

That "chick chick chick" noise is very annoying :doh:

You convinced me Frank :laugh: I will do the same thing to my buckets when i rebuild the NA engine for the SR (Y)

 

[Bombardier]

CR bucket come in different thicknesses depending on how you want the gap.