2F Engine "resistance" cause? (2 Viewers)

[xumFJ40]

I recently picked up a 2F short block. When turning the crank by hand, there is what I will call resistance, in other words it hits a point in the cycle where it wants to stop (not rotate freely) and I have to apply more pressure in order to fight past the resistance and continue the cycle. This happens when cylinders 3 & 4 are about 2/3 the way into their up stroke. I can push them through the resistance and to the top of their stroke. Then, as they start to go back down, the resistance is present once more, where it is slightly harder (but not difficult) to get past, before returning to smooth, for the remaining cycle until I get back around...

Any thoughts? My assumption is something in the bottom end, bearings, etc.

Thanks,

 

[pjohnson]

Pull the head and check the cylinders. Good time for a new HG anyway.

 

[middlecalf]

Spark plugs are out, right?

Duh, short block. Lol.

 

[xumFJ40]

Pull the head and check the cylinders. Good time for a new HG anyway.

Short Block... Head has already been removed...

 

[SteveH]

Maybe put some ATF in all the cylinders and see if it smooths out the rotation after a few trips around. That would tell you if piston or ring friction is part of the problem. If you don't know the history of the engine, pulling a few bearing caps might be very revealing.

 

[FJ40Jim]

Sounds like a funky bore. Rust at the bottom of the 2 cylinders that are swinging by BDC is dragging on the rings.

 

[pjohnson]

Short Block... Head has already been removed...

Doh! My bad.

 

[xumFJ40]

Sounds like a funky bore. Rust at the bottom of the 2 cylinders that are swinging by BDC is dragging on the rings.

Could be I guess... in general all the bores look pretty good from what I can see from the top... guess I will see more once I drop the pan...

 

[ToyotaMatt]

Could be I guess... in general all the bores look pretty good from what I can see from the top... guess I will see more once I drop the pan...

- Has your crank pulley been removed yet ?

- Timing Cover removed ?

- did u remove ALL your Solid Lifters yet ?

- Has your Distributor Been Removed Yet ?

- Cam Shaft Removed Yet ?

- how " short " is your short block ?

- some photos of the current state of your " short block " would be helpful too

 

[xumFJ40]

- Has your crank pulley been removed yet ?

- Timing Cover removed ?

- did u remove ALL your Solid Lifters yet ?

- Has your Distributor Been Removed Yet ?

- Cam Shaft Removed Yet ?

- how " short " is your short block ?

- some photos of the current state of your " short block " would be helpful too

Understood...

* - no crank pulley... just BFN
* - Timing cover in place
* - "I" haven't removed any lifters...
* - no Dizzy in place
* - cam is in place... I assume... as timing cover, and presumably chain haven't been removed.

One thing that looks odd is the combustion residue on the top of #3... all others are uniform...

 

[Steamer]

* - cam is in place... I assume... as timing cover, and presumably chain haven't been removed.

No chain. It's gear to gear.

 

[hooter]

you lost me at chain.....

 

[Steamer]

you lost me at chain.....

I just thought he was assuming there was a timing chain.

 

[xumFJ40]

I just thought he was assuming there was a timing chain.

Doh... yes, like I said... haven't removed the cover... I'm sure the cam is still in place, unless the previous owner did something with it...

 

[1MOA]

Doh... yes, like I said... haven't removed the cover... I'm sure the cam is still in place, unless the previous owner did something with it...

It may be art now.... who knows....

 

[FJ40Jim]

It looks like #3 piston has touched the cyl. head. It would need to be missing a fair amount of rod bearing for that to happen, but is possible.

 

[xumFJ40]

Thanks Jim...

Yeah, that is what I was wondering... should be able to confirm once I get it on the stand.

 

[xumFJ40]

So... finally got around to putting the motor on a stand and flipping it over...

Looks like the Oil Pan took some damage during transport and the resistance that I was feeling was when the big lobe of the crank came back around on the outboard side of #1...

 

[xumFJ40]

Next question is:

Is this a normal amount of metal to find in the bottom of an '81 2F? First motor I have been into, and while on one hand this seems like a lot of debris, on the other hand it's 38 years old and seems like it is in pretty good shape.

Either way, the motor is going to be bored and rebuilt so I'm not worried... just more curious.

View attachment 2014972

 

[xumFJ40]

Bottom of pan...