I think the TSB is referencing the two incividual "C" clip style.
Not the single elongated clip. [ which I have used on many over the 35 years without any problem...

Any time you hand ball peen hammer an end it is next to impossible to do a uniform job. It may look OK to the eye, but you can be assured it has weak fractures and uneven streach and stress points.
If you have the right tool, go with it. If not , I prefer the single clip w/nose in rotation direction and clip on the rear side of the chain.

Larry Bible, BTW, Where did you see those comments about leather punches ?

It is often safer ( for the objects nearby and does a more uniform job ) to use a drift or the like and hit it with the hammer rather than trying to peen with ( of all things ) a ball peen hammer....this of course is the method used to lock some types of hardened valve seats into heads..... Greg

The TSB referenced was for the SINGLE "C" clip. The two separate "roundish" clips were discontinued long before. Supposedly the reason given was because the diameter of the pins is reduced at the groove for the C clip making it weaker.

Makes sense .
Thanks

Alistair

You made some good comments about my post.
I have thought about the fragility of the cam sprocket and will try and peen the link below the sprocket, out in the open so to speak. But I don't know if I have enough room, too lazy to get up and go look... it's 3AM.

And congratulations on your retrievel of your spring (you idiot...). I freaked when the end of my old chain disappeared into my engine when I disconnected my chain ( too many beers-me idiot!)
Fortunately it was the passenger side end, and was easily retrieved with a magnet. Whew.

Are you folks in autumn weather now? What does your part of the world look like? Do you have electricity yet? LOL.

Dropping things (#@*&%?!!)
 

I did the same thing once..dropped the timing chain into the cavity when replacing it. I had the new chain hooked to the old one with the new link, and didnt think I needed to fasten it ...the end of the new chain slipped off the link and both ends of the existing chain fell into the cavity....
I am the type to use a lot of "persuasive" words when working on cars....but this time, when I saw that chain disappear, I stepped back, sat down, and sat silent for about ten minutes, thinking "is this a dream, or did I really just see what I think I saw". I managed to fish both ends out with a coat hanger, and amazingly, the loose link was still attached, and no teeth were skipped...new chain went in, and timing was perfect.

There speaks the words of wisdom Arthur, Are you a metallurgist by any chance? I thought this when I first heard about hammering/peening the ends over!, but I was too lazy to mention it and cause an argument!. Mark, When I first disconnected chain, it fell into the motor too! God Im clumsy!, fished it out with one of those spokes from an old umbrella!, Just re-checked injection timing, was 2 degrees out, but it was dark when I first set it! Its amazing how much a couple of degrees seem to make to the MB Diesel, my old chain had about 5 degrees "free play" ie. the cam was about 5 degrees retarded cause of wear/stretch in old chain, Glad Ive changed it, It couldnt have lasted much longer before catastrophic tooth jumping or worse! Well, Its Spring here, been some nice weather over the last couple of days, just right for all those nasty little jobs I have put off over the last months.

Better go, She who Must Be Obayed wants to go for a day out, ( Probably Shopping--How Boring!)

Alastair

My apologies! I thought I read "new south wales"...sorry.

I am going to mention something with regards to the physics of chains... but this does not mean that I prefer the clip type keeper....

A properly fitted and designed chain would not be decreased in strength due to the metal taken out of the pin for the keeper because the load is borne by the side plate. So all the force applied to the chain would be felt by the barrel of the pin terminating at the edge of the part which the keeper is designed to keep in place......

However, because I know how hard it is to get close fitting things apart which have been even accidentally swaged...and having seen some clips come off of motorcycle chains when they messed with tree limbs or the like.... If it were really important... for the chain to stay in place... I would carefully peen it....

I would be horrified if I dropped the chain because the shop manual is pretty clear about one not wanting to do that...

With a proper anvil, a flat punch, and a small hammer NO force should make it to the camshaft sprocket. This is not a situation like a blacksmith encounters where he needs to " strike while the iron is hot " . So there is no speed factor here... place the punch and anvil and strike... place the punch and anvil and strike, place the punch and anvil and strike... Greg

Thanks Greg,
This is basically what I had in mind, easy does it. I figger that the peen marks just need to be enough to discourage the end plate from moving.
I thought about modifying a punch into a V shape to mimic the other peen marks.

Thanks again Greg, I can always count on you to give a thoughtful and intelligent answer, and thanks to all who contributed.

I have put many clips on chains and haven't had a failure. The only challenge is to fit the end plate securely over the pins far enough to fit the clip. If done wrong, the end plate could be bent and compromised.

Hmmm. I could use the old plate-drill out the holes a bit for some slop and use this as a template for evening out the pressure required to seat the plate...