Forum Ferguson

John

When you buy the Sparex rings kit for the TEF, you get 6 new rings. But old pistons have only 5. How do you mount them ?

For people who don't know, see on the photo bellow the difference between pistons (6 rings on the right and 5 on the left)

Dear John,

Some more informations about the new piston ring kit I baught from Sparex :

I have compared the dimensions of the rings : rings nr 1, 2 and 3 are 2 mm thickness. Ring nr 4 is composed of a "back spring" plus 3 rings and a "washer". Then rings number 5 and 6 are 3.96 mm thickness.

In my motor, the actual ones are same dimensions except the fact that there is only one oil ring nr 5 or 6 (thickness 3.96 mm). Otherwise they seem to be similar.

Yann

Ignore the 6th Piston Ring. If you only have 5 ring grooves in your piston just use 5 rings but make sure that the bottom ring is the oil control ring and also make sure that you have the spacer ring at the back of the oil control ring too.

Dear John,

Thanks for your answer. Its exactly what we have done when we have reassembled them.
But I have a question concerning the new rings in old pistons / sleeves : When everything has been reassembled, we have noticed that rotating the engine manually was becomming more and more difficult while increasing the number of pistons linked to the crankshaft. Especially after connecting the fourth one. Everithing has of course been mounted with oil and after some rotations it is comming more "friendly" but remains a little bit hard : Is it something normal

(note : the loose on the rings - which we call the "cut" in french - was aroung 3 mm instead of the 0.7 maximum before we changed them. now the loose has decreased to something around 0.7 if I remember well).

Thanks for your input and best regards,

Yann