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jdemaris
03-29-2006 09:05:50
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Re: 2020 seeps late in reply to Superhank, 03-28-2006 13:01:08
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I could write volumes on this subject. It was our number one problem with Deere
equipment up to the 50 series - new and used. The most important cheap improvement you can make is to add a hydraulic pump
destroker for $5 and five minutes work. You need to ascertain a few things if you hope to improve cold starting. Some 2020s
when new started great down to 20 degrees F, while others would barely start at 50 F. It
caused us many customer complaints, especially when two new tractors sat side by side,
yet were so different. My neighbor bought two 4020s new, and happened to get a pair
like that. One would, and still will start at 10 degrees with no ether or block heater. The
other was a miserable starter since the day he got it, even in the summer. He put up with
it for a year, and let the dealer tear it down once, and then got rid of it. This is in the late
60s and Deere did not have any good remedies at the time. That pretty much goes for all
the Deere diesels until they got to the 50 series. Before then it was a crap shoot - and it
depended on which end of the spectrum the tolerances were when the engine got
machined and assembled at the factory. So, did your 2020 ever start good? If "no", then it probably suffers from a high block
deck, resulting in low piston standout - as well as other manufacturing problems. Deere
made several attempts to put a band-aid on the situation over the years, including
different fuel delivery settings, static timing settings, thinner head-gaskets, changing
injector installed height, valve-in-head depth brought up to .020" and .040", etc. The one
thing that did work pretty well was the new pistons with a higher top piston-ring groove.
They were originally created to fix the 40 series ag. tractors which gave us the most cold
starting and smoking problems of any Deere we ever sold. The older 2010 diesels
smoke and skipped when cold, but still started pretty good. Other more simple things that can make a difference are #1 install a hydraulic pump
destroker for $5. Takes five minutes to install and can make a huge difference in cold
starting (unless you already have one). #2 try advancing the static timing by 2 degrees. #3
if the tractor isn't overfueled now (doesn't smoke when worked hard) turning up the fuel
delivery one-third turn of the head screw can sometimes make a big difference,
depending on the tractor - it's a ten minute job to do it. Quite often, after years of hard starting and ether use, the top rings shatter to pieces. Then the tractor always starts hard, but can still run pretty good. These are the tractors
that are often said to be "addicted" to ether, and in fact, they are. For that, the only cure
is new pistons, rings, and sleeves. Another problem that can be chronic is if the tractor ever had a "bad" valve job where
the seats and valves were ground without maintaining proper valve depth in the head. It
is critical on Deere engines of that time period. Deere had us pulling the heads off of
brand new tractors, espcially the 40 series, to fix the problem - often existing right from
the Deere factory. The intakes should be around .020" deep and the exhausts .040" deep.
Deere had us shaving heads on some new tractors or installing TRW valves with thick
heads to get the standout right, but it makes more sense to do it with new, thicker seats.
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