[AJD] 620 Piston question

Duane Larson jdlarson at comcast.net
Tue Mar 1 21:47:24 PST 2005


Dean,
>From FSB 259 we find
Cyl dia 4.6871-4.6885
Piston skirt (end of skirt) 4.6816-4.6826
piston head end 4.6430-4.6470
piston pin hole id 1.4170-1.4176
piston pin od    1.4166-1.4170
piston pin bushing id    1.4180-1.4190
If you need additional info let me know what you need.
Regards,
Duane

----- Original Message ----- 
From: "Dean VP" <deanvp at att.net>
To: "AT JD" <antique-johndeere at lists.antique-tractor.com>
Sent: Tuesday, March 01, 2005 10:35 PM
Subject: [AJD] 620 Piston question


>I did some work on a couple spare 620 aluminum pistons today and was a bit
> surprised that they didn't completely match. One piston has the casting
> number A5555R (inside the skirt) which is the STD sized JD piston for 
> 620's
> and 630 gas tractors. It also has 620 G stamped on the piston top. All as
> expected.
>
> Then the surprise came. The second piston does not have a casting number,
> looks like the other one except no casting number and has 630 G stamped on
> the top of the piston.
>
> Now I'm aware the 620G and 630G pistons are the same but can anyone 
> explain
> the differences I have noted?
>
> Both pistons have been knurled on the skirts opposite the pins. I assume
> that has been done during an overhaul at some time as I don't think they
> come from the factory that way. On first blush they don't look all that 
> worn
> and ring lands look pretty good to me. It's been a long time since I have
> seen a set of new 620 pistons, if ever. :-)
>
> Also, I'm taking two 620 blocks into a machinist tomorrow for Magnaflux 
> and
> dimensional checks.  Any one able to point me to a manual or document that
> gives the specs on the pistons and cylinders? Or have those handy?
>
> Thanks for any and all help in advance.
>
> Dean A. Van Peursem
> Snohomish, WA 98290
>
> I'm a walking storeroom of facts..... I've just lost the key to the
> storeroom door
>
>
> www.deerelegacy.com
>
> http://members.cox.net/classicweb/email.htm
>
>
>
>
>
>
> _______________________________________________
> Antique-johndeere mailing list
> http://www.antique-tractor.com/mailman/listinfo/antique-johndeere 




More information about the AT mailing list