mid 20's Buick Piston removal

[Hubert_25-25]

I am about to go through a 1926 Master engine that has sat for decades.  I will be dropping the oil pan later this week.  I do know from my Standard engine that the pistons only come out thru the bottom because the big end of the connecting rod is larger than the cylinder bore.  When I assembled my 1925 standard engine, the crankshaft was out when I installed the new pistons.     

My question is, can you remove the pistons out the bottom of the engine with the crankshaft still in place? 

 

Thank you,

Hugh 

[Roger Barrett]

Yes you can.

[Morgan Wright]

On mine, it took a little trial and error to get the crankshaft in the right position to squeeze the pistons through, but they do come through on all 6 pistons. It helps to remove the spark plugs so you can turn it by hand.

[Hubert_25-25]

Roger and Morgan, 

   Thank you for the response.  I want to do a thorough inspection of the engine and I was leaning toward pulling the pistons if I was able.    Hugh

[Oldtech]

Yes, the bottoms of the cylinders are tapered so you can wiggle the rings in when you replace the pistons. no compressor needed. Just some care and finessing. Turn the crank so it is "sideways" to the one you want out. 

[Hubert_25-25]

Oldtech - Thanks for the note about not need a ring compressor.  I did use one on the last rebuild but felt that the taper would come in pretty handy.

 

Below is why you drop the oil pan on a motor that has been left neglected for decades.  Photos of the oil pump screen and the oil pan.  Observe how the screen is broken on both sides.     Hugh

[Oregon Desert model 45]

That looks familiar.  This is how mine looked when I opened it up.  There were a few places at the bottom of the pan where rust pitting had thinned the metal so much that holes opened up as I was cleaning the pan, and more kept opening up as I was trying to weld them closed. 

Kevin 

Edited June 30, 2022 by Oregon Desert model 45
edit (see edit history)

[Morgan Wright]

Looks like there was water in the oil. Usually the pan is pretty rust free otherwise.

[EmTee]

2 hours ago, Morgan Wright said:

Looks like there was water in the oil.

I was thinking the same; the green color suggests glycol antifreeze contamination.

[dibarlaw]

Ah.... another dive into the Okeefinokee swamp. That was the same as what I saw in my 1937 when I got into it in 1987. The inside of the block had a thick coat of parafine based oil. My 1925 Standard was fairly clean with just a bit of sludge. But the oil pump screen did need repair as did the flanges.

The oil distribution tube had a failed solder joint that they had used RTV blue on.

Make sure these joints are solid.

My 1925 Master had sat for a while. Also I do not believe the lower end had been inspected since it was returned to the road in the 1970s. That pan was very swampy and the screen on the oil pump was damaged. I sent that pump and my Standard pump to Reeve enterprises in Cazanovia NY. for rebuild.

 Both cars have clean pans now as I had to replace their timing gears. So, I had to drop the pans again to search out all the fiber timing gear crumbs.