ReUse Risk - Cam Follower (Lifter)

[barron_williams]

Doing pushrod seals today. Can't complain, its been 15 years.

Looked at the lifters. Two areas with some pitting on the exhaust (see pictures).

What am risking with reuse?

I know, if money was no object, I wouldn't even ask. But, at $60 apiece, I have to weigh it against other expenses.

In my mind the spectrum is something like this -- things that:

1. Absolutely must be fixed (or replaced).

2. Have some wear, but aren't at the replace stage yet.

3. Look bad, but function fine (cosmetics).

So, opinions on where this lifter is on the spectrum?

Regards, Barron

 

[ATL83]

How many miles on these? How does the cam look? It doesn't look terrible, but my understanding is that these things are somewhat of a cancer, and eventually it will worsen. I think the bigger question with these is always "where did the offending metal come from?" I just had to replace all of mine. The two exhaust lifters looked like the surface of the moon, but the intakes looked pretty similar to yours. One of the exhausts actually bit my cam too. Not bad, but visible pitting. At the time I had my heads out to one of the "gurus" for reconditioning, and I picked his brain about the situation, and whether or not to replace. In regards to the very minimal pitting on the intake lifters and cam, all he said was "that would bug me." There was no scientific explanation of tolerances or wear patterns or whatever, just the knowledge that deep in your engine lurks a "potential" problem.

I realized that it would indeed bug me too, so I replaced everything. Strangely, the lifters put me out $240, but I got a perfectly good cam w/gear on ebay for $20. Seemed a little backwards.

 

[Ken F]

I sure wouldn't put it back in, especially if what I'm seeing in the picture is pitting.
if it is an imperfection on the lifter, it's going to wear your cam. Maybe rapidly, maybe slowly. (again hard to tell from the picture)
Your cam has a hardned surface, once you wear through it, you are down to much softer metal, which wears away quicker.
Most likely you will wear through on the top of the lobe first, so be sure to inspect the lobe that one came out of very carefully.

Can you feel it with your fingernail?

Ken

 

[toooldtocare]

First there is one pit, then two, then....... Replace them. The cam may be ok, but check it too.

 

[85k100lt]

Lifter looks good for age.

Lifter looks good for age.

What is the current mileage and is that an original lifter???

 

[barron_williams]

Original lifters (1974 R90/6).

144,000 kms.

Yes, I can feel them with my fingernail.

Cam looks ok.

Barron

 

[85k100lt]

I would continue to run - just keep the oil clean.

 

[ISAMEMON]

44 at moto bins

for that many miles look real good
if those are your worst, adn you dont have the money, then I guess your ok
good oil, constant

 

[barron_williams]

What Happened

Just to close this out for posterity -

Here is how all four cam followers looked:

<a href="http://s1211.photobucket.com/albums/cc437/121xray76/?action=view&current=CamFollowers4.jpg" target="_blank"><img src="http://i1211.photobucket.com/albums/cc437/121xray76/CamFollowers4.jpg" border="0" alt="Photobucket"></a>

I knew I had to replace at least the two intake followers. Funny how it was the intake that had the most pitting. The left side exhaust looked just about perfect. I was really on the fence with the right side exhaust (the focus of my initial post).

In the end, I invested in the next 15 years by replacing all four.

For anybody else in the same situation, Cycleworks offers a "refacing" service for vintage models. I wrote and asked about the /6 and Dan told me it could be done and would take a couple of weeks. I decided, mostly in the interest of time, to replace them. But, the resurfacing looks like a good option if you are just getting started on a project and have a couple of months downtime.

http://www.cycleworks.net/index.php?main_page=product_info&cPath=28_6&products_id=315

When the new followers arrived, theywere the same hight and diameter, but looked different -

<a href="http://s1211.photobucket.com/albums/cc437/121xray76/?action=view&current=NewCamFollower.jpg" target="_blank"><img src="http://i1211.photobucket.com/albums/cc437/121xray76/NewCamFollower.jpg" border="0" alt="Photobucket"></a>

Rusty Gill from Max BMW replied to my question, "Yes, they are interchangeable. BMW updated to the straight window because the angled window tappets were cracking at the top/bottom of the window."

So, there you have it.

If anybody has a use for the followers I pulled out of my /6, send me a PM and I'll pass them along.

Regards,

Barron

 

[mikegates]

i would reuse those see mine http://forums.bmwmoa.org/showthread.php?t=50870&highlight=lifters