Colt Case Ingersoll Garden Tractors

I would never have figured it out if it wasn’t for everyone that responded here

here's one of my favourite songs ever




https://www.youtube.com/watch?v=zf5mu_JBM9w

Wow, you could almost hear the collective sound of gears turning to figure this out.
Now let's get this 446 back to work.

Eugen wrote: ↑Wed Jan 26, 2022 1:35 pm Dave, did you forget the BF-MS?

16HP twin Onan BF-MS bore is 3-1/8
16HP twin Onan B43M bore is 3-1/4



The good news is that you found the old piston. All hope is not lost!

Doh , Ya , the nice thing about BF-MS is it is the same small block and I am told can be bored to standard B43M

Dave

Well, I spoke too soon. When I got home I pulled one of the heads and the “new” pistons are stamped STD as well. Even if the one on the other side was a different size at least one cylinder should fire I’d think. Could it be the rings are wore out?

Vivala446 wrote: ↑Wed Jan 26, 2022 6:25 pm Well, I spoke too soon. When I got home I pulled one of the heads and the “new” pistons are stamped STD as well. Even if the one on the other side was a different size at least one cylinder should fire I’d think. Could it be the rings are wore out?

I thought you put two BF-MS pistons in.

I was basing that on the receipt I had. When I took the head off I saw the STD stamped in it but it was very faint

That was based on the receipt I had. When I pulled the head off I saw the STD stamped very faintly. The one that I know is STD didn’t have as much slop in it as the other side. And the surface was kind of rough. And I noticed some oil that looked like it had been squeezed up the cylinder to the top in the course of turning the engine. Could it be the rings are just wore completely out? Or could it be that there are size variations within the STD?

I am greatly confused now. So you bought two BF-MS pistons. Did you put them both in or only one?

Lol. Yeah, I have weaved a twisted tale.

When bought the tractor it was running on one cylinder— the passenger side. The drivers side did was in pieces. I bought what we’re described as BF-MS pistons to replace them. I replaced both pistons and rods with the supposed BF-MS ones. I didn’t mess with anything on the engine other than the pistons and rods— didn’t mess with the valves, etc. Once I got it all back together the starter will turn the engine all day long but it will not fire. Plugs are sparking. Valves work, etc.

As I said the piston that replaced the original damaged one has a lot of slop in it.

That’s where I’m at now.