T&T: Cummins BT5.9 shroud

[Peter Bennett]

My Cummins 6BTA5.9 doesn't have any form of shroud around the
alternators/front of engine, and I don't recall seeing any indication
of one in the manuals. I have been thinking that I should add
something to prevent me from getting tangled in the belts....

Sunday, July 22, 2007, 7:59:44 PM, Steve wrote:

SS> I've reworked my 12v charging system, including changing the stock 105A
SS> Delco alternator to an Amptech 140 with a Balmar 512 regulator. After
SS> spending the week aboard cruising last week, I got a chance to see how
SS> the system performs under other than weekend hops. It's lacking.

SS> I'm having trouble getting the alternator to charge at full amps. After
SS> some investigation, I've determined that the cause is the temp sensor on
SS> the alternator. It's doing what it's supposed to do. Part of my upgrade
SS> was to add ventilation to help keep the alternator cool, and it helps,
SS> but the shroud on the front of the Cummins causes the discharge air from
SS> the alternator fan to blow back onto the alternator, and after 20 or 30
SS> minutes of run time, it's hot enough to cause the regulator to unload
SS> the alternator from high temp.

SS> My question to the list is if anyone has encountered this situation in a
SS> Cummins and found a workable solution. I did remove the shroud, and the
SS> alternator stays up on full charge until the voltage on the batteries
SS> goes to float. I considered cutting the back 2" of the shroud away &
SS> replacing it with expanded metal, allowing the discharge air to get away
SS> from the alternator. The battery temp sensor is also throttling the
SS> regulator, but that's another issue. My engine room temps are easily in
SS> the 120F plus area, I know, too hot. I thought the added 250 cfm blower
SS> would help, but I still have some work to do on the ER ventilation.

SS> Steve Sipe
SS> Solo 4303 "Maerin"
SS> Back to work... grrrr...



-- 
Peter Bennett, VE7CEI    Vancouver, B.C., Canada
Ennos 31 "Honeycomb"
GPS and NMEA info: http://vancouver-webpages.com/peter 
Vancouver Power Squadron: http://vancouver.powersquadron.ca