I am in the process of restoring my Thirtyfive 5C503. It needs a lot of engine work. Two of the pistons are broken. I am hoping to get the rings removed from other two. I purchased it with the engine disassembled and sitting outside for many years. Any advice or suggestions are welcome. Thanks!

I have one for sale but wont part out if you are interested in making 1 out of 2. 5C475 located in Purdy MO

Thanks for responding. I sent the 2 broken Pistons to Antique Crawler Parts in Wyoming to possibly be repaired. I will keep you in mind in case I need another whole machine.

Please keep us in the loop with that piston repair, when you say 2 pistons were "broken" and are going to be repaired I'm curious to hear how it goes, I bought a set of Cat 30 pistons recently that looked good in the box when they arrived but discovered one has a crack from the piston pin to the skirt and I assumed it was not repairable. In theory finding another 30 piston should be a lot easier than finding one for a Gas 35, good luck with your restoration.
Thanks
Mike

"crawlerholler" wrote:

I have one for sale but wont part out if you are interested in making 1 out of 2. 5C475 located in Purdy MO

Dont know anything about this stuff but I have 4 pistons and rings 6B-3912. I heard they were kind of interchangeable depending on engine. Let me know.
Thanks Jimmy.

6B3912 is the same as the 3H1438, 6B4011, 3H1414, etc.

"Snimmy1501" wrote:

Dont know anything about this stuff but I have 4 pistons and rings 6B-3912. I heard they were kind of interchangeable depending on engine. Let me know.
Thanks Jimmy.

If you are planning on resleveing the bores you could make it 1/8" smaller and use 30 pistons which are redly available. The rods and valves are the same are the same as a thirty and all the head parts are the same as the 2 head thirty's. We have used D8, 2U valves by shorting the stem and cutting down the O.D. of the head and shorting the length of the D8 guide. Hope this helps.