pistons 4 rings or 2? (1 Viewer)

[euclid]

A buddy has a local shop rebuild his August of 74 FJ40. The shop said the pistons have 4 rings per piston, and they are used to seeing 2 rings per piston. Any ideas on why there is a difference? Should he take care to replace them with the 4 ring versions?

 

[sport]

The 4 rings are standard in the F. Here is the description from the TLC FAQ page:

"The main differences between the F and the 2F are the 2F's larger bore, the F's 2 compression and 2 oil rings versus the 2F's 2 compression and single oil ring..."

Sport

 

[Gumby]

I have a 2F piston on my desk right in front of me. It has two compression rings and one three piece oil ring.
I went out and grabbed a F piston as well. Two compression rings, one three piece oil ring and one one piece oil ring. Goofy looking.
2 piston rings are very rare in four stroke gas engines. The vast majority have 3 rings.

 

[Gumby]

here's a pic