Cam wear

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Rust bucket
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Cam wear

Post by Rust bucket »

Just a quick question about cam wear, i'm rebuilding my 1098 with rebore,crank change, chain and sprockets,oil pump,and followers, the cam i would like too reuse if i could but there is a little wear on the exhaust lobes, starting with the rear lobe they are 13.53 13.48 13.48 13.50in along with a bit of pitting on the side of some.
Reading some of the problems people have had with new cams damaging there rebuilt engines, :x is this old one acceptable?.
philthehill
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Re: Cam wear

Post by philthehill »

Can you confirm the measurements because if you take it as read you have cam lobes of 13.5 inches. I do not know about wear they seem to have grown.

bmcecosse
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Re: Cam wear

Post by bmcecosse »

Why/how on earth could a new cam damage a rebuilt engine? Your cam sounds as though it is well within the original tolerances. It will be fine.
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Nutts
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Re: Cam wear

Post by Nutts »

I would look to see if the lobes have worn through the hardening, if so you will see like elongated rings on the narrow end of the lobe.
Otherwise as other have said it wont do any harm.
You could always get it re-hardened.

New cam in old bearings would be more of a problem if it was tight or loose.

Peter
Rust bucket
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Re: Cam wear

Post by Rust bucket »

Should read 1.353, 1.348, 1.348,1.350in, :wink: ....it's just that i've read some members have had problems with a change of camshaft, no elongated rings just a little pitting on the sides of three lobes.
liammonty
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Re: Cam wear

Post by liammonty »

My new cam destroyed my totally engine- badly manufactured helical cam drive gear destroyed the dizzy drive gear, and the resulting metal filings ran the new bearings (mains and big ends). So you're quite right to ask! Mine wasn't a standard cam. If you want to know where it was from, I'll gladly PM you, but I dare not say it in public for fear of being banned!!!
bmcecosse
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Re: Cam wear

Post by bmcecosse »

Ah yes - I remember the story now. But NO ONE else on the Mini forums etc has ever reported such a thing happening - and yes - I asked around. But the cam in question here will be fine - although do by all means post up a picture or two of the lobes. And rehardening a very ordinary 'standard' cam like this would not be an economic proposition. Plenty of Mini cams around if you want a different cam!
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Rust bucket
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Re: Cam wear

Post by Rust bucket »

That's a thought but it would have to be a 998 cam because i don't want too fiddle around getting the new oil pump to fit, also i'm fitting a 1275 head so i only want the same lift as as a Minor cam.
bmcecosse
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Re: Cam wear

Post by bmcecosse »

Any later Mini cam will require a later type oil pump...... And all have 'safe' lift up to and including the very desireable MG Metro cam .
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Rust bucket
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Re: Cam wear

Post by Rust bucket »

Okay thanks bmcecosse, you are always quick too respond to many questions on this site, i think the Lord has blessed you with much knowledge of the poached egg.
liammonty
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Re: Cam wear

Post by liammonty »

The problem seems to be isolated to me! Worth mentioning though, that 2 cams from the supplier caused damage, but when replaced with a NOS MG Metro cam (genuine BL) I had no more problems at all.
bmcecosse
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Re: Cam wear

Post by bmcecosse »

I do remember it - and I asked specifically if any Mini owner had that problem with the supplier you had mentioned - and got nothing but praise back.... It was a strange one.
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liammonty
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Re: Cam wear

Post by liammonty »

I've put it down to (a very expensive) experience! MG Metro cam is nice though, even in a 1030, so all OK in the end.
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