[AT] Hot Bulb Engine (tractor)

[Dean VP]

Dick,

Check this out:

1910-1950s[edit]

Direct injected small Diesel engines still were not practical[10] and the prechambered indirect
injected engine was invented, along with the requirement of glowplugs to be used for
starting.[12][13] With technology developed by Robert Bosch GmbH pump and injector systems could be
built to run at a much higher pressure. Combined with high precision injectors, high speed Diesels
were produced from 1927.

The hot bulbs started to develop cracks and breakups and were gradually replaced by water cooled
cylinder heads with a flat hot spot.[14] Over time the compression ratios were increased from 3:1 to
14:1. Fuel injection started from 135 degrees before top dead center with low compression down to 20
degrees before top dead center with later higher compression engines increasing the hot air factor
[10][15] for ignition and increasing the fuel efficiency.[10] Glowplugs finally replaced the
preheating with a blowtorch methods and engine speeds were increased, resulting in what is now
classified as an indirect injection Diesel.[10]

Hot bulb or prechambered engines were always easier to produce,[10] more reliable and could handle
smaller amounts of fuel in smaller engines than the direct injected "pure" Diesels could.[10]

Dean VP
Snohomish, WA 98290

" . . . The tree of liberty must be refreshed from time to time with the blood of patriots and
tyrants. It is it's natural manure . . . " Jefferson


-----Original Message-----
From: at-bounces at lists.antique-tractor.com [mailto:at-bounces at lists.antique-tractor.com] On Behalf Of
DDSS
Sent: Sunday, May 04, 2014 10:34 AM
To: atis
Subject: [AT] Hot Bulb Engine (tractor)

My son in Chicago called me. A neighbor has an old tractor that he no longer wants and asked my son
if he would like to have it.  The neighbor says it's a 1939 Bosch hot bulb tractor.  My son says he's
not sure the tractor is Bosch but for sure the engine is.  The neighbor uses a blow torch to start
it. It uses #6 diesel.

My son said the tractor is too large to fit through the door to his barn (his Boomer w/cab just
barely clears the top of the door opening).  He says this old tractor is really big.  I cannot wait
to see the pictures.

I cannot find a single hit on the internet for a Bosch tractor.  Anyone know if Bosch ever made a
tractor?

Any experience with hot bulb engines?

Thanks

Dick 

_______________________________________________
AT mailing list
http://www.antique-tractor.com/mailman/listinfo/at