MTFCA Forum

I know the best option is to remove the head to replace a connecting rod, but is it possible to remove a connecting rod from the bottom? I have plenty of shims in the rod, but the car has always had a knock. I’ve discovered that one of the connecting rods must be bent because the piston end is all the way up against the piston on one side and it has worn the side of the Babbit on the connecting rod to where there is a pretty decent amount of slop on the crankshaft. I did measure the crankshaft and it is Completely round and straight. I know this is the lazy way, but to replace one rod I hate removing the head because I absolutely hate dealing with antifreeze.
The engine does not have cast pistons it actually has Ford Y block pistons in it so there is no chance of a ring popping out because that would be a total pain when you pull the piston down.

I've done it once. Had #1 rod go bad on a tour and a kind soul loaned me a replacement. Not a lot of fun laying on your back with the light of a flashlight but definitely doable.

Maybe I should qualify my comment as I was dealing with stock T pistons. I don't know if your Y block pistons use a different retainer for the wrist pin.

I tried it once, on a 26 with the 4 dip crankcase on number 2 rod. It had the 3 rings above the wrist pin. Even then, I pulled it down too far and got the bottom ring out of the groove. Couldn't go down or up because of the center main and tried to use a ring compressor under the block. Very hard. Much easier to do it with the head off. However, it is very hard to get the rings in exactly the same rotation they were before they were pulled so it might use a bit of oil after doing so. If you get the babbit re-poured, be sure to find someone who will straighten the rod and pour and bore the rod to an exact fit to the crankshaft.
Norm

walber wrote: ↑

Sat Mar 29, 2025 11:31 am

I've done it once. Had #1 rod go bad on a tour and a kind soul loaned me a replacement. Not a lot of fun laying on your back with the light of a flashlight but definitely doable.

Same experience on an Arizona national shoot out tour.
Removing a rod from the bottom is a PITA, but very doable.

I dont get your claim that a ring cant pop out if you bring your piston down a bit too far. It will. Be very careful not to lower the piston too far.
But, if it does pop out, you can use a large hose clamp or enough smaller ones together to make a ring compressor.
It is much harder to get back up with the narrow 3 piece oil scraper set than a 1/4" one piece ring.

Outside of an emergency road repair without a new head gasket, (as in @ home in the shop) I would pull the head.

greenacres36 wrote: ↑

Sat Mar 29, 2025 11:07 am

I know the best option is to remove the head to replace a connecting rod, but is it possible to remove a connecting rod from the bottom? I have plenty of shims in the rod, but the car has always had a knock. I’ve discovered that one of the connecting rods must be bent because the piston end is all the way up against the piston on one side and it has worn the side of the Babbit on the connecting rod to where there is a pretty decent amount of slop on the crankshaft. I did measure the crankshaft and it is Completely round and straight. I know this is the lazy way, but to replace one rod I hate removing the head because I absolutely hate dealing with antifreeze.
The engine does not have cast pistons it actually has Ford Y block pistons in it so there is no chance of a ring popping out because that would be a total pain when you pull the piston down.

Actually, I was astounded to find that the coolant drain on my T is at the lowest spot in the cooling system. Most cars aren't. It's no big deal to drain the coolant into a bucket, then pour it back in when you are done.

Just pull the head. FAR easier.

Advice taken. I’ll take the head off. In my experience I should know better because taking the apparent lazy way out always ends up costing me a bunch of more effort. I think that’s just the way it is.
I certainly appreciate the quick replies.

I did replace a rod in Henrietta through the bottom, the main reason being to avoid disturbing her original unrestored appearance. We did it on a hoist, so working positions were optimal. With her cast iron pistons, the lower ring had to come out of the bore. A used replacement rod was hand scraped to fit, lapped in with Timesaver by rocking it back and forth while hanging down and then refitted. We did struggle getting the bottom ring back up the bore Until a young turk came by and did it with a standard ring compressor!
That was six years ago, and she is still running as sweetly as ever. I was prepared to take the bottom plate off again to make adjustments to the bearing but it has never been necessary to date.
A side benefit in her case was the removal of a lot of granular carbon debris that was trapped between the pan sides and the bottom plate horse shoes.

Allan from down under.

Hi Brian,
Sounds like you have come to the conclusion that removing the head will be easier than from the bottom. That may be a good choice. I have
heard of guys doing this even with iron pistons. A couple of ideas, if you have Y block pistons they should have snap rings to retain the wristpin
& that may be a PITA to get out? I have done this myself with aluminum pistons & there are some issues with it. After much cussing getting the
wristpin bolt lock off, then you have to remove the bolt. When you break the bolt loose you are putting a lot of twist on the rod & retightening
the bolt. You don't have a way to ensure the rod you install is the same weight as the other three? As far as keeping the rings from coming out
the bottom of the cylinder I used a bar bolted to the pan with a hole in the middle & a piece of 1/4" all-thread threw the hole in the rod to pull
the rod so as to minimize the likely hood of pulling it down to far. In my defense I did this the night before a speedster run & I didn't have a
spare head gasket & the one in the engine was a modern style that can not be reused like I hear the copper ones can. Good luck & happy Ting.
Craig.

Might be a good idea to mike the journal to see if it’s got wear or a flat spot. It’s much easier to remove a piston with the head off. If you have a copper gasket remove the head carefully and it still might be good enough to use it again. I’ve done that a few times but that’s up to you and there are different opinions about it.

Reusing a head gasket is a $50. decision. So far I have gone with a new head gasket with the model t. I have successfully reused head gaskets in the 60's when I had even less money than I do.

Art Mirtes