Last week I was driving my cousin's T when we lost a rod bearing. Quite a racket. To confirm the diagnosis we drained the oil and a piece of the babbit came out in the oil. Question is, can you remove the rod from the bottom. Take the cap off, lower the piston far enough to slide the pin out without going past the ring and then replacing with new rod?
No, you can't take it out from the bottom. Even if what you propose is possible, it's far more difficult than just removing the head.
Dale.....I have done it on number 1 rod. After removing the pan inspection cover, was able to carefully remove the wrist pin bolt, take the rod cap off and lower the piston enough to slide the wrist pin out enough to drop the rod out. The oil rings kept the piston from sliding out the bottom. If a ring pops out, use a hose clamp if your fingers do not work.
Had the rod bearing re-done and installed it in reverse order.
I can not comment if it can be done on the other rods. However...It Can be Done on #1 Rod!
How did you loosen/tighten the wrist pin clamp bolt without stressing, (twisting), the rod?
With the piston slid down to expose the wrist pin, placed a punch in the wrist pin with one hand and an extension/socket in the other to remove the wrist pin bolt. Had to rotate the crankshaft a little to gain the need clearance to get the job done.
It may have taken a little more time underneath but saved draining the coolant, removing rad./hoses and head. Also, saved the cost of a new head gasket.
This was a friends car that I worked on in the parking lot on the last day of a model T tour.
I had pulled the inspection cover off to verify only #1 rod was bad. Others on the tour that was watching me said they had never seen this done before......why not try it.....what did we have to lose?
If more than one rod was damaged, I would have not attempted the task....however, it worked out great.
If you have cast iron pistons the oil ring is at the bottom and will pop out. I guess you could get it back in but I wouldn't want to mess with it.
I have been able to re-use the head gasket. Mind you I install head gaskets dry. If you have them glued top and bottom then that may be a different story,
The engine had aluminum pistons. The bottom wide piston ring on cast iron pistons should not be that difficult to squeeze back in place. Just MHO on that issue as I have not had a ring pop out when I did not want it to do so.
After having done it, I do not consider it that difficult when doing only one rod. In this case, only #1 rod required replacing.
Has any one else replaced other rods besides #1 without removing the head?
I have changed a rod on an A crank T from the bottom. Had to fit the rod too. That was a pain but it beat having to pull the Chevy head and the plate below it to get to the top of the piston.