Cam chain replacement without breaking engine

I was afraid someone would ask for that. Well here goes. First photo is the side the plate was pressed on and before I modified the buck nose - so the peening is off-centre. Not too worried about that as the 'factory' peening looks to hit the very edge of the pin anyway. Second photo is the other side after a couple of teaks with the buck diameter reduced so it better centred the riveting tool. Trying really hard not to over think this - would love to keep peening but terrified I'll over tighten my last good joining link. Now wish I had started a new topic for this - what does everyone else do - the thought of splitting the cases and replacing the cam chain without breaking it was even more terrifying. My engine is in pretty good shape and even after 120,000km the bore and pistons are within standard service limits so haven't needed to bore oversize so thought the bottom end shouldn't need any attention.

RBY's cam Chain repair thread.

KZQ wrote:

RBY's cam Chain repair thread.

I think KZQ is saying it would be great to start a new thread about your work, making it easier for future cam-peeners (pun intended, America is electing new prez in Nov). 

And Thanks for the pics!

 

Trying really hard not to over think this - would love to keep peening but terrified I'll over tighten my last good joining link. 

Take a small flat blade screwdriver, insert under your peened link, try to 'pry' the link apart. Carefully note any movement. If movement, if it wiggles, how much does it wiggle?

Go to a factory link and repeat, compare.

If identical, and I think they will be, you're done. Put the tool down and walk away!

I can't imagine there being much side stress on that side plate. And if something went south bad enough to create that kind of stress, well, your phooked anyway. 

 

For the record-
The pins of the master link are an interference fit in the side plate of the master link. (.003"-.004")

First thing is to install the master link on to the chain and then press the side plate onto the master link pins. You know when you have it just right when the chain is ever so slightly tight when you try to bend the chain at the master link. if it's too tight  flex the chain sideways to loosen it up until you're happy.

Now you're ready for peening. Set up the pieces of the tool and place over the pin to be peened and tighten down the peening head by 3 flats of the peening head and note the position of the handle of the peening head, then back off to inspect the end of the pin. You're looking for an impression just enough to see that the end of the pin is not flat anymore. Any visible impression indicates that you have yielded the end of the pin and displaced the metal. Any impression will be enough to ensure the pin can't come out because , remember that the pin is an interference fit to start with and now you have displaced more metal outboard of the side plate making the interference even greater.
if you don't see an impression in the end of the pin, install the tool again and tighten up the 1 more flat of the head of the peening end from the position you noted from the first squeeze. Back the tool off and check the end of the pin again looking for some kind of an impression. if you see an impression, you're done. If not repeat this step and again go one more flat of the peening head. It's that simple.
RBY's pic of his finished chain is great. Great job for a first attempt. The impressions look really good and the link is not binding. Patience is a virtue. The only tricky part of doing this job with the chain installed in the engine is dealing with all of the plates. There are 3 or 4 plates + the master link + the outboard side plate and until you have all the pieces together and the side plate pressed over the pins of the master link, there's a possibility of dropping a piece down into the engine. Stuffing the cavity with rags is paramount.

Great job RBY !! Be proud. You earned this one and thanks for posting.
KB

dcarver220b wrote:

KZQ wrote:

RBY's cam Chain repair thread.

I think KZQ is saying it would be great to start a new thread about your work, making it easier for future cam-peeners (pun intended, America is electing new prez in Nov). 

And Thanks for the pics!


 

Yes! Thank you Don.
I realize that this software upgrade has been a hassle with no PM system. But I'm working on it and when I finally get the forum working properly I'd like to have a threaded forum that will be a resource in the future without mixed topic threads.
Thanks
Bill/KZQ