Sunday 2 December 2012

Fitting new Rootes piston rings to a 1963 Imp piston

Now and again we have the choice to re use whats original given the status of the parts, in this case why fit a new set of pistons and replace those which are by now quite historic?


This engine is now some 49 years old, its not perfect but will be a fine runner with brand new Rootes piston rings fitted. In this case the bores and pistons are standard sized with no valve cut outs in the pistons, finding a standard bore engine of this age would be hard to do? The original Rootes piston rings were a perfect fit!


There are three types of rings, this is the center one, it fits with the small groove upwards.


This is the top compression ring, chrome steel or plated I believe.


The lower and third ring is named a Scraper and is the oil control ring.



Fit the new rings firmly but carefully, ensure the gaps are correct in the bore before you do so, in this case and on a used motor the gaps were fine. stagger the ring joints and place them to the side of the piston and not on the thrust face.



Use a quality piston ring compressor, this one is sized to fit the Imps 877cc to 998cc pistons, thats 68mm to 72mm in diameter.


Right click on the picture to enlarge it and see the seriously high quality of engineering that Rootes produced in their Imp engines fifty years ago!
Pistons and conrods fitted and all tab washers are in place and folded over the bolts, dont forget the thrust washers that fit either side of the center main bearing!

Roy

To free off seized Hillman Imp piston rings try the link below.

http://royckdboats.blogspot.com/2012/12/how-to-remove-seized-piston-rings-from.html