| Author | Message | ||
     Kellenbm |
My crank bearing went out on the male rod bearing. I replaced the crank. When I put the wrist pins in I noticed that the front pistons wrist pin could easily be moved back and forth inside of the piston and rod. The rear pistons wrist pin is tight. Should I get new pistons should they be tight or can I have one pin move like that? | ||
| Kyrocket |
Did you replace them all? When I had the same problem my original wrist pins were tight but the replacements were loose. Well, not loose, but looser than originals. The replacements slid in and moved freely where as the originals had to be forced out. | ||
| Ratbuell |
They're "free-floating" design, not press fit. Pull the sticky one and see if it, the rod, or the piston are scored. | ||
| Oldog |
I'm With Joe on that check for any damage or discoloration indicating excessive heat / out of round. BUT I had a similar deal, the pin slides and turns in the rod with out slop, but was tight in the piston and had to be pushed out and in. WARNING NEVER HIT or TAP the pins into the rod / pistons, this can damage the big end bearings a Pressing tool can easily be improvised.. | ||
| Firemanjim |
Try a polish with some 1000 wet/dry | ||
| Stev0 |
The pin fit is only a couple of tenths of a thou and should give some resistance to being pushed. They shouldn't fall through under their own weight. It's not unusual to have little end damage when you've done a big end. Can you get any sideways movement out of the pin in the little end???? | ||
| Mmmi_grad |
after a massive rebuild from a crank bearing going out, you owe it to yourself to replace the pistons. There are alot of stresses put on a piston. Really, do you want it to explode later ? The Rod bushings should have also been fitted at that time to the piston wrist pins. | ||
| Lynrd |
Old school greybeard engine tip of the day:  Put your wristpins in the freezer. Put the pistons in water that was boiling a minute or so ago. Drink a beer- PBR is recommended  . Pins will slide right into the pistons. No sanding or any of that stuff. | ||
| Kellenbm |
To be clear the Pin and the rod end bushings are good. It is my pistons that may have unequal wear. I am thinking the stress of the knock has caused the front piston pin sleeve be loose. As opposed to the rear. Because it was the front pistons bearing that failed. I might have to save up and buy new 10 over standard. | ||
| Ratbuell |
Check with your machinist before you buy pistons. No sense going 10 over if you don't have to...save that .010" for later, in case you really need it. | ||
| Stev0 |
plus one on the piston.. only go as big as ya need to |
