Forum

[Barry N]

One of my cam followers/tappet has some very slight surface pitting on the underside (the lifting face). There is no depth to the marks and most of the surface is still pretty smooth. How do they generally wear and should I worry about it? What is involved in extracting and refitting the follower, should I decide to replace it?

[Norm]

Barry,
To get the tappet out it isn't easy. First you have to remove the cam spindle, heating the case arond the spindle first. If the cases are apart you can then tap it out from the inside. Then you need to remove the tappet guide out after heating the case around the tappet guide area. You then need a tappet guide removal tool. With the guide removed the tappet can be removed out the bottom

[Alan R]

High guys----might I just expand a little on NORM'S input and play Devil's Advocate ? Basically, if you do decide to change the follower then plan your time (and finances) to do the BOTH of them. It's one of those jobs you just can't go back to later on. And if the cases are apart then-----how's the main bearings looking ?? etc. Sorry but it has to be factored-in to your thinking even if you decide not to go any further down that particular road.

[Barry N]

Thanks both for your input. Since I already have the cases apart for a 612 conversion, I have decided to get a new set of tappets and guides to go with the new cams. I was surprised to find some surface scuffing/flaking on the original exhaust cam lobe (at around maximum lift), which had slightly roughed up the tappet. Although I smoothed the tappet with a very fine stone, I was still not happy with it. The engine had only done 6500km, so I was very surprised to see this, especially as I have always used old-type "Classic" oil (with zinc) as recommended for our type of engine, and it has never been thrashed. I am putting it down to dodgy hardening of the camshaft. The rest of the original components were all excellent, including the Indian main bearings (although European bearings will be fitted).

[Norm]

Barry, just remember you won't get the tappet guide out or back in without the tappet guide tool

[Barry N]

Yes Norm - I'll be getting the tool. Cheers!

[Phil Ashbrook]

My original 1995 tappet guides just got replaced with the improved bronze type with my new sports cams , with the tool it still a 2 person job , one with the blow torch on the casings and one for pulling the new parts out of the freezer screwing on the inner part of the extracter tool ind drifting it home with the tappet leg inserted from underneath before the drive into the cases ...and it must be done in a brisk way so it wont warm up , the thermal fit is good and my new ones should last 20 years .

[marsie]

I have just replaced the followers on my 51 G2. The job is made more difficult by the addition of return springs between the head of the follower and the guide block. As I have no friends, this was accomplished on my own by positioning the case half on bricks over a primus stove.The fingers got a bit burnt, but the blisters went down after a couple of days.