Spongy cam followers (DJ)

[Yozza]

Ay up,
The old girl is struggling, I think she wants a new engine/re-build (very low compression 8.5bar) ). I did notice a significant knocking (tappets), took the rocker cover off and No.2 exhaust cam follower very spongy, (I could push the rocker with just my thumb ). I've taken all cam followers out a while ago to put fresh oil in them, however, it seems No.2 doesn't want to play properly.
First question is, why do they go spongy? Secondly, what are my options?
Cheerz

[toomanytoys]

I had one go soft on me ages ago.. had to replace it as it wouldnt bleed down even after 2 attempts

The ther thing is, what oil are you using> a mineral 15w40 is whats needed, or if the engine is tired a 20w50..

Thing is, if you have removed tappets have you got the colapsible pushrod tubes?

[kevtherev]

First question is, why do they go spongy? Secondly, what are my options?
Cheerz

question first.. how long has the engine been unused?
have you tried taking it for a good 10 mile run after a oil and filter change?

[Yozza]

Thanks for the replies fellas,
I use Fuchs 15w 40 from GSF, but I may go for the 20w 50 next time I'm picking up my 2 monthly top up. I haven't got collapseable pushrod tubes, I did this job when the heads were off.
This van is my daily drive she does't stand still unless she's on the ramps.
Cheerz

[toomanytoys]

Well its a risk to put the soft one back in.. fit a new one..

As for preload on the rockers when reassembling, only do 1/2 (half) a turn from just touching..

[Yozza]

Any ideas as to the root cause for failure? As I remember it, it's two precision ground parts and a spring full of oil and bled?