Mikep_86441
NAXJA Forum User
- Location
- AZ
Tell me if this sounds like BS.
The piston slap that we get is significant when it happens. The videos I've seen are showing what has to create a 1/16" skirt/cyl wall gap. That's crazy.
This xj we just got has at least one piston slapping. I was thinking of trying to extend their life by adding ptfe (teflon) buttons to the skirts to take up the slop. If they wear out, put in new ones. With these relatively low rpm 4.0 engines, I think that a button or 4 on the piston skirt might at some solid life to the worn piston.
I found a rod of this ptfe on amazon for $15. It's 2 feet long.
The head of the button will be tapered so that it can be filed down like a tiny volcano so the skirt of the piston can be fitted to the cylinder bore nice and snug. I bet the 1/4" or so hole in the piston skirt can just be done with a drill press. It will need a counterbore for the head of the button to sit. The holes don't have to be perfect because the button would get filed down to what ever lets the piston fit into the bore.
Just wasn't sleeping and thought of this for when I have to yank the oil pan off and see what's causing the piston slap.
If anyone has a worn 4.0 piston, could you take some calipers and measure how thick the worn piston skirt is ?
Here's a pic I found of a racing piston prepped for buttons.
https://www.rbracing-rsr.com/turbo/bullett/bulbenefit/bulpstn_peek2.jpg
The piston slap that we get is significant when it happens. The videos I've seen are showing what has to create a 1/16" skirt/cyl wall gap. That's crazy.
This xj we just got has at least one piston slapping. I was thinking of trying to extend their life by adding ptfe (teflon) buttons to the skirts to take up the slop. If they wear out, put in new ones. With these relatively low rpm 4.0 engines, I think that a button or 4 on the piston skirt might at some solid life to the worn piston.
I found a rod of this ptfe on amazon for $15. It's 2 feet long.
The head of the button will be tapered so that it can be filed down like a tiny volcano so the skirt of the piston can be fitted to the cylinder bore nice and snug. I bet the 1/4" or so hole in the piston skirt can just be done with a drill press. It will need a counterbore for the head of the button to sit. The holes don't have to be perfect because the button would get filed down to what ever lets the piston fit into the bore.
Just wasn't sleeping and thought of this for when I have to yank the oil pan off and see what's causing the piston slap.
If anyone has a worn 4.0 piston, could you take some calipers and measure how thick the worn piston skirt is ?
Here's a pic I found of a racing piston prepped for buttons.
https://www.rbracing-rsr.com/turbo/bullett/bulbenefit/bulpstn_peek2.jpg