HELP! I Need Cylinder & Piston for 1932 Airman

I'm a new Franklin owner ~ not knowing much about Franklins, I bought a 1932 Airman A16 163!

The engine had not ran for approximately 10 years.

I put 2 oz. of Marvel Mystery Oil into each cylinder & let it set for a couple days, the turned the engine with the starter.

It turned over freely so I put the plugs back in, hooked up a temporary gas tank & started it. It started right up &

sounded pretty good! I notice a slight miss & found cylinder #5 not running.

I did a compression check & found no compression. I pulled the cylinder and found the top of the piston damage - it

looked like it had actually 'burned' on 2 edges at the top! The black 'wedge' at the right side is actually a hole right

through the piston(See picture)! It also scored the cylinder!

I also pulled #6 to examine (on right), it looks good.

So . . . I need a replacement cylinder & piston. The piston measures 3.512" and the cylinder measures 3.514".

The piston & rod appears to be original Franklin parts. This car has only 50,xxx miles so I don't want to totally rebuild the engine!

Anyone have these parts?? Please reply telling me what you have & $$.

Bill

This is no help, but reading your thread reminded me of a movie I watched not too long ago called "World's Fastest Indian", where the guy in the movie actually cast a replacement piston that he needed. Hopefully, you won't have to go to that extreme, but wouldn't it be cool to have the ability to do so? if you haven't seen it, perhaps you can rent it and watch it while waiting for parts to fix your Franklin! Good Luck.

Is the cylinder so scored that you need a new one, or could you bore/hone the cylinder?

I have several parts engines and lots of loose engine parts on the shelf. If you want to try a new cylinder I can find you one, but I think you'd have to get it machined THEN you'd know what size piston you need. A cylinder can look good, but it could have a large taper to it and could end up being bored a lot oversize before it is true again.

I don't know how safe it is to use an already used piston... I'll let others on the board add their wisdom. If you can re-use an already used piston, then I'm sure I have one. Would 3.512" be marked as 0.010 or 0.015" over?

If the piston measures 3.512" does that mean it isn't the original piston? If you scrape the carbon off the top, is it marked as oversize?

I'm going to suggest that if you have 2 jugs off and 2 rods off that you at least check the other 4... Maybe check the rod bearings on the other 4 as well.

I guess it all depends on what you want to do with the car. If you want to drive the car on parades 2-3 times a year, then I'd try to find a used good piston and either replace the cylinder or recondition the existing one. If you want to drive it to Syracuse for the Trek, I'd order 6 new pistons from Egge. Take all the jugs off and get them bored true for the new pistons. While the jugs are apart and at the machine shop, get the valves done. This is all assuming that the rod bearings are good....

Rob

I will look to see what I have. I have a bunch of 32/31/30 jugs. All will work but the trained eye will notice that missing webbing on the 30/31. If you do not find one let me know and I will go on the parts hunt in my stash.

I am using a 6" digital caliper to measure the pistons & cylinders.

I just measured again and got different readings! This time both pistons 5 & 6 measured 3.494" -? I measured at the very

top of each piston.

The cylinder #5 measured 3.514 top & bottom, but the scores on each side are pretty deep.

Cyl #6 measured 3.514 at the bottom (haven't taken head off of #6 Cylinder).

I cleaned the top of pistons #5 & 6 & took a picture of pistons side by side. It appears that the engine has been re-done;

the pistons are stamped on top X149 & have 5 punch marks on #5 & 6 punch marks on #6 piston.

Here is the picture of the two pistons side-by-side:

What does X149 mean?

Hi WIlliam -

Lots of good suggestions above for you. I will support them in saying you will need accurate measurements of existing parts to know what is going on and what options you have. Once you understand what is going on with #5 and #6, you may well want to measure the other cylinders & pistons.

Pistons must be measured with a micrometer on the skirt, perpendicular to the wrist pin. Measure along this 'ridge', at the bottom of the skirt, middle and top of the skirt, jsut below the oil ring groove. The biggest reading is the number you want to record.

Cylinders must also be measured with a micrometer as they wear both oval and tapered. Measurement must be taken along the same axis as the measurement on the piston - meaning perpendicular to the pin and from the bottom to the top of the cylinder, jsut below the ring ridge. It will be tapered - growing larger in size as you go 'up'. Record this taper. The smallest reading in the cylinder, less the biggest point on the piston skirt is your piston clearance. Get these numbers and let us know.

If you plan to put this car into service and drive it, you really will want to know the engine is in good condition. You indicate it looks like the engine was rebuilt. The clean rods suggest so. Factory pistons suggest it was done a long time ago, or at least with NORS parts. But you don't know who did it, or why #5 failed. So it might be a very good idea to check the rest of the engine, as Rob suggested. Franklin parts are out there, but not as plentiful as other makes and when things go bad, they can damage other parts, as well as interfere with our enjoyment of the car!

If the engine shows little wear and parts/clearances & workmanship are good - you can replace the one piston and either repair, or replace the cylinder. A used FRANKLIN piston that is in overall good condition is perfecetly acceptable to use (but realize that they are not easy to find in good condition - especially a factory oversized piston. Ring groove wear is the biggest problem with used pistons. Groove wear can be repaired, and it can make sense to do so on one piston). New parts are available if that's the route that makes sense.

Rob's suggestion to check the rod bearings is a very good one.

It might also be a very good time to check the valves/guides since you have two jugs off.

Keep us posted and feel free to contact me directly if I can help, or if you have a local shop help you, they can call me with questions any time as well.

Tom Rasmussen

763-786-1518

It sure is great to have 'friends' on this forum advising me!! As I've said, I'm quite an amateur when it comes to this vehicle. I really appreciate the help I've been receiving!

Mike West from Livonia, NY is sending me a standard cylinder & piston which he said were running together in an engine.

I'm still curious what the meaning of X149 stamped in the top of the pistons.

You will want to measure both carefully to determine if they will work satisfactorily. Excessive clearance leads to skirt failure on original parts. Badly worn ring grooves can at worst cause failures similar to what happened to #5.

It would be nice if they work out.

Tom

Thank you for your comments. I think I'll take it to our local automotive machine shop to have it checked out.

I may have a clue as to why the #5 piston failed; somewhere back in it's life someone added an A/C system to the car. They installed the condenser coil right against the blower intake. I'm sure this must have restricted the air intake to the blower.

Due to my wife's medical conditions I want to retain the A/C system in the car.

I plan to move the condenser to the underside and install an electric fan on it.

Good theory, but then would one not expect to find near equal problems on all cylinders?

It could be a yet-to-be-discovered problem....

tom

Mike West sold me a .030 o/s cylinder & piston. I installed them and the engine seems to be running on all 6 cylinders ~ yeah!

Now to continue with all the rest I have to do to the car!