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MG MGB Technical - Reluctant Tappets

I have my UK 1980 18v 847H engine on a stand and am stripping it down for a refresh.
I thought things were going too well!
Began removing the tappets...one to four came out ok with some wiggling, got to number five, problem.
With my finger inside I can lift it up easily about one centimetre when it comes to a definite stop against some obstacle. Tried the remaining tappets..number seven came out fine, but six and eight were just the same as five. Turning them in the bores doesn't help.
There is no obvious ridge of material in the casting
preventing them lifting higher but I guess that there must be, however slight. It begs the question how did they go in when manufactured?
I haven't checked the cam yet, but the tappets are all pitted on the bottom.
Obviously I want to get them out and some new ones in later. So what is the best way forward? Should I get the Dremel out, with a grinder tip, and remove some material, or is there a better way? Your help appreciated.
ph barton

Once you've taken out the ones you can, invert the engine, remove the cam shaft and take the remainder out this way. I had one of these when I rebuilt my engine, it seemed to be a small piece of casting that was stopping it coming out of the top. Once I'd got it out a careful bit of filing removed the obstruction.

Bob
R.A Davis

Leave your Dremel in the cupboard, no place for it doing an engine rebuild
And yeah, sounds like your camshaft is toast anyway, most 18v's suffer from it eventually
You'll find the bottoms of the followers are pitted and if bad enough which it sounds like they are, they will be worn across the face with burrs hanging out past their diameter stopping them from being able to be removed normally
As bob has advised , camshaft out and drop the followers out the bottom instead of dragging all the rough bits out through the follower bore and damaging it.
use care- not a grinder
willy
William Revit

Doesn't turning the camshaft raise them enough to grasp and lift out? I had all mine out many years ago to check the faces because of what sounded like a heavy tappet, with the camshaft in the engine and the engine in the car. Maybe the stiction of the push-rod in the follower was just enough.

It's (the tapping) still there over 30 years and 65k later.
paulh4

They lift easily to the high point on the cam and then no further. It's very much like they are hitting a physical barrier around the top of the casting. I imagine it's a seldom seen problem, but maybe some regular engine builders out there have an idea? I need to resolve this as I intend putting a Piper 270 cam in, so a higher lift will be problematic.
ph barton

It could be that there's just a buildup of hard rubbish on the outside of the bottom exposed, unused barrel of the follower stopping it coming up through the bore in the block,they may well pull out with a bit of jiggling, but, it could also be a damaged follower--If you're going to remove the camshaft anyway the safest way is to do as Bob has suggested, tip the engine over, pull the cam out and then push the followers out in the opposite direction, towards the cam, instead of dragging them through the block
William Revit

Update...
Thanks for your comments.
I did remove cam with engine inverted and removed stuck followers.
The three offending followers had all splayed out slightly on the lower outer edges. New examples run down the bores as they should.
ph barton

This thread was discussed between 07/04/2021 and 21/04/2021

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