Camshaft issue?

[ginga]

Parked the van up in October, I've moved it around and driven it occasionally but sorting bodywork out so not moved much. Last couple of times i started it i noticed it was back firing on lhs through carb (twin 34s on a 1776). Reset valve clearances but no improvement, I then tried turning engine over by hand whilst watching rocker arms. The inner valve on no 3 doesn't move but it is the pushrod not moving rather than a stuck valve. Although could a stuck valve then cause a broken cam lobe?

Am I right in thinking this is the inlet valve and that it can only really be the lifter or cam lobe? all other valves on that side work fine. Pushrod seems fine.

Cheers for any help.

 

[megaaircooled]

Is this a fairly new engine.

 

[ginga]

No it is a few years old, bought 2nd hand about 4 years ago and run trouble free since then, of uncertain history shall we say which leads me to believe it needs a full rebuild.

 

[megaaircooled]

If the cam and followers were not burned in correctly you can wear the lobe away,normally happens within 1000 miles.no3 is normaly the one thats effected.

 

[megaaircooled]

That is 3 and 1

 

[megaaircooled]

It should effect 1 as well if it is cam lobe.

 

[ginga]

The backfire is only on lhs, didn't check no 1 actually so i ll do it tomorrow, other than backfire engine sounds good. I ve been round europe a few times in it now so we can safely say its not new.

 

[megaaircooled]

If it is only no3 it maybe cam follower on 3 thats failed.

 

[ginga]

is that still splitting the case job?

 

[megaaircooled]

Yes it is.But double check

 

[ginga]

Really appreciate the help, i ll have a good look tomorrow at no 1 but doesn't look like its going anywhere for awhile!

 

[megaaircooled]

Any news.