Cam Jam

Post by **Shawn** » Fri Dec 16, 2005 9:55 am

If I've removed the:
timing gears
cam retaining bolts (3 off)
tappets (all 8 )
distributor drive
petrol pump

why won't my cam pull out?

It has about 1/16" free play and them jams solid - It won't even turn. Seems to be jamming on the front bearing.

I've removed several Mini cams and they all came out easily...

Help!!!

Post by **Matt** » Fri Dec 16, 2005 9:57 am

Just guessing, dont know how the cam attaches, but 3 bolts to hold the cam seems a bit odd to me, have you missed one?

Post by **KirstMin** » Fri Dec 16, 2005 1:05 pm

Matt wrote:Just guessing, dont know how the cam attaches, but 3 bolts to hold the cam seems a bit odd to me, have you missed one?

3 bolts is correct, its a triangular plate that holds the cam in place isn't it? Mine came out easily. But I took the sump off, turned the engine upside down and pulled it out from the inside.

Post by **bmcecosse** » Fri Dec 16, 2005 7:10 pm

Just temporarily put the chain wheel back on - and using that turn it slightly and wiggle it about - it will come out! There is nothing else holding it in.

Post by **wanderinstar** » Fri Dec 16, 2005 7:54 pm

By "tappets" I presume you mean pushrods. But what about removing cam followers, no mention of you removing these.
Ian.

Post by **Shawn** » Fri Dec 16, 2005 9:54 pm

wanderinstar wrote:By "tappets" I presume you mean pushrods. But what about removing cam followers, no mention of you removing these.
Ian.

I've removed both the pushrods and the cam followers.
My first thought was that I'd left a cam follower in and it was causing it to jam.

bmcecosse wrote: Just temporarily put the chain wheel back on - and using that turn it slightly and wiggle it about - it will come out! There is nothing else holding it in.

Tried that too, when I pull it out about that 1/16" it binds and won't be turned, pushed or pulled. I have to tap it back in to "unbind" it - then it turns freely. I actually broke a chainwheel by levering it with two screwdrivers. (luckilly I have a spare - didn't realise they weren't solid!)

Is it possible the front bearing has worn in such a way as to bind the cam?

Post by **bmcecosse** » Sat Dec 17, 2005 8:32 am

Very strange - try turning the crankshaft in case there is an interference with that. Otherwise - whip the sump off and have a look-see. Also - take the oil pump off which will give you access at the back.

Post by **Shawn** » Sun Dec 18, 2005 8:30 pm

Un update for anyone who's interested:

There was the slightest wear in the rearmost edge of the rear bearing which caused the cam to bind. Had to 'drift' it out. Replacement fitted fine with no play or binding.

Gotta love those afternoon jobs which wind up taking two-and-a-half days!

Post by **KirstMin** » Mon Dec 19, 2005 11:52 am

Shawn wrote: Gotta love those afternoon jobs which wind up taking two-and-a-half days!

Well done mate, I know that feeling!

Post by **bmcecosse** » Mon Dec 19, 2005 1:14 pm

Hmmm - never had that problem. What cam are you now fitting ?

Post by **Shawn** » Tue Dec 20, 2005 2:20 am

An AEA630 ex Mini 1100 - I think you put me on to them - Thanks!

The engine I'm experimenting with is an old Austin A40 Farina 948cc which I formerly thought was knackered, but turns out to be in surprisingly good condition. I'm fitting a 12G202 head, the AEA630 cam and a 1-1/2" SU (ex'78 Moke 1100) on the standard inlet/exhaust manifold.

I've also experimented on the head in terms of a light port grind and polish. It might make a difference - some of the casting edges in the ports were quite large! I've tried to clean up casting edges in the manifold in the same way, but the standard exhaust will still be restrictive.

Basically it's all been done with bits I had access to for free, I'll see how this lot goes before I shell out for a new exhaust system.

Post by **bmcecosse** » Tue Dec 20, 2005 10:54 pm

Ah yes, I remember the thread now. The 202 head will need skimming to get the compression ratio up! As standard the chambers are 26.1 cc, against the normal head with 24cc - so if you fit it without skimming you will lose performance. I would suggest 60 thou off - which will lift the CR slightly higher than before - every little helps.