19 replies to this topic

[KTS]

pulled the engine apart to try and diagnose the source of white metal in the oil and found a number of cam followers are pitted

 

Cam and followers were new when the engine was built around 600miles ago.  Cam lube was used during assembly and the 20min run at 2K rpm bed in procedure was followed on initial start.

 

[Spider]

It looks to me they are just poor quality chilled iron followers. They possibly had inclusions in the Iron when they were cast or the Iron itself is just breaking apart, probably from poor heat / chilling treatment.

If I can suggest, APT have good quality followers, I pretty much only use theirs.

[PoolGuy]

Difficult to tell from the photo, but were they all spinning properly, at least two of them look like they weren't.

[KTS]

It looks to me they are just poor quality chilled iron followers. They possibly had inclusions in the Iron when they were cast or the Iron itself is just breaking apart, probably from poor heat / chilling treatment.

If I can suggest, APT have good quality followers, I pretty much only use theirs.

 

Thanks - i'll have a look at their stuff

 

Difficult to tell from the photo, but were they all spinning properly, at least two of them look like they weren't.

 

followers 6 & 8 (No.1 on the left) look like they haven't been spinning properly with a distinct polish line from the cam lobe (in the right light), the rest of them look like they have fairly even wear across the faces

 

is it a question of honing the follower bores to resolve that problem ?

[ACDodd]

I must admit that pitting does look flakey and not normal, also note a big variation on the chamfer on the face of those followers, I am thinking cheap. What rocker ratio and valve springs are you using? Did you use break in oil?
Did you check the radius on the end of the followers before fitting?

Ac

Edited by ACDodd, 06 April 2024 - 06:19 PM.

[KTS]

I must admit that pitting does look flakey and not normal, also note a big variation on the chamfer on the face of those followers, I am thinking cheap. What rocker ratio and valve springs are you using? Did you use break in oil?
Did you check the radius on the end of the followers before fitting?

Ac

 

They weren't the most expensive set, but sourced from a reputable supplier

 

Rockers are 1.4:1, springs 180lb, break in oil was not used

 

Radius was not checked before fitting 

 

i'll drop the supplier a line and see what he has to say

 

cheers

[KTS]

conveniently, i did take a photo before i fitted them.

 

[unburntfuelinthemorning]

 

They weren't the most expensive set, but sourced from a reputable supplier

 

Rockers are 1.4:1, springs 180lb, break in oil was not used

 

Radius was not checked before fitting 

 

i'll drop the supplier a line and see what he has to say

 

cheers

 

What did the supplier say?

[MrBrown]

I’m Interested in what and where you purchased. I can’t afford another incident and I am in the market for these. You can message me if you would prefer discretion. Its would be good to know. Thanks!

[Spider]

It does appear they have all been rotating. Those with the bits missing have clearly been of poor materials or not correctly hardened - or both.

It seems for some time now, the followers from the more common suppliers have been too hit and miss on what you'll get. I've been using APT or Iskys the last 10 or so years to get away from these sorts of issues.

[KTS]

the followers were these : https://www.calverst...m-follower-set/

 

I did have a conversation with Keith about the issue and shared some of the photos of the followers and camshaft, and his opinion was that the poor quality of the cam grind was the most likely cause.

 

by way of an example of the cam quality - 

 

[Rorf]

That camshaft journal is shot, looks like it has been running in the cast iron block without bearings. If it was ground that way then there is your problem as the lobes might look the same. The pic of the new cam followers look like they have been radiused. Followers I bought from MiniSpares a few years ago looked flat but seem to be performing well 8000kms later

[Spider]

conveniently, i did take a photo before i fitted them.

 

 

Looking at these again, they don't look like they have been ground on a radius but are on a cone. That's likely not the cause of their failure, but will ultimately give poor life and wear the cam prematurely.

[whistler]

 

conveniently, i did take a photo before i fitted them.

 

 

Looking at these again, they don't look like they have been ground on a radius but are on a cone. That's likely not the cause of their failure, but will ultimately give poor life and wear the cam prematurely.

 

I believe these are the cam followers mentioned by OP. https://calverst.com...-follower-set/. Ground to radius is mentioned. I use a set of these in conjunction with a Piper 255 supplied by CalverST.

[Spider]

 

 

conveniently, i did take a photo before i fitted them.

 

 

Looking at these again, they don't look like they have been ground on a radius but are on a cone. That's likely not the cause of their failure, but will ultimately give poor life and wear the cam prematurely.

 

I believe these are the cam followers mentioned by OP. https://calverst.com...-follower-set/. Ground to radius is mentioned. I use a set of these in conjunction with a Piper 255 supplied by CalverST.

 

 

 

If they were ground on a radius, they wouldn't be able to wear in the centre. Have a look at KTS's first set of photos.