[AJD] can I use the 820 exaust valve in my D?

[Louis]

I had a head redone for a John Deere D SN # 30888.  I used JD part #
D3410R for the valves.  Last year they were $89.73. Now they are $105
from Deere. I make a habit of replacing the valve springs.  Weak valve
springs can cause all types of problems.  The springs for this tractor
are part # 485R.  They are $37.50 each.  I just looked back in my
records; I also used this same valves and springs in a late 1927 John
Deere D.

 I just had a head redone for a styled D.  The valves for that tractor
are $110.  They are part # D3411R.  The valve springs for this tractor
are part # D1724R.  They are $15.75 each.

Most of the D valves that I have seen have been shot.  You need to be
careful of stem wear.  I have seen them worn .060".  That can cause all
kinds of problems. I had a machine shop refuse to reassemble a head with
valves that had that kind of wear.  It made sense after they explained
it to me.  They said before the head was disassembled and cleaned, there
was carbon and other crud in-between the valve guide and the valve stem.
This helped hold the valve fairly square in the guide.  Now that the
crud was cleaned out, the valve could cock in the guide and stick open.
If that happens while the engine is running, it could end up breaking a
piston and other damage, i.e. thrown connecting rod, broken block,
etc...

If you buy used valves or use old valves, they need to be completely
checked.  It would hurt to have them magnafluxed to check for cracks.
You don't want to do all that work and spend all that money to have the
head of the valve break off and ruin your engine.

Louis Spiegelberg

-----Original Message-----
From: antique-johndeere-bounces at lists.antique-tractor.com
[mailto:antique-johndeere-bounces at lists.antique-tractor.com] On Behalf
Of Eric LaCruze
Sent: Monday, December 27, 2004 7:16 PM
To: Antique John Deere mailing list
Subject: Re: [AJD] can I use the 820 exaust valve in my D?


I asked my cousin exactly what he did, here's his response.

Eric

----

Eric,  I had a set of valves from a later model D cut down to use in my 
'28 D.  I don't remember off hand what the serial # break is,but the 
later d valves have about a 1" or 1.5" longer stem but are otherwise 
dimensionally the same.   The original shorter valves for the '28 are 
(or were) still available from deere, but you can find a nice used set 
of the later ones for a fraction of the price.
_______________________________________________
Antique-johndeere mailing list
http://www.antique-tractor.com/mailman/listinfo/antique-johndeere