I was looking at a photo of BNSF 9805 with two MU cables. Looking closer, it didn’t have any plugs, but instead was a short hose on the anti-climber below the plugs. I thought how similar it looked to BN’s fuel tender equipped locomotives, so I compared the two. To my suprise, the hose length, positioning, and connection was a match to BN’s system. After looking at sister units, I determined BNSF 9804-9837, or 34 of 61 units in order #966706 had these hoses. They appear to have been installed by EMD and removed in the mid-2010s. Further attempts to find information on this has revealed nothing. As far as I know, these are the only MACs with this installed. I have attached a photo with a comparison. Any ideas or info on why these were installed on only these units, and if they were used?
If you have pictures with enough resolution, see if you can determine what kind of connectors are on the end of those hoses.
Those look like some kind of compatibility with ‘gas tenders’ to me, rather than hoses from an extended-run ‘diesel fuel tender’ arrangement… although I wouldn’t know for sure, and there will be others here who recognize it. Perhaps a range of likely power was given the necessary external piping ‘early’, pending the results of testing, but not actually used in the event.
Here is some of the regulatory stuff involving the gas tenders:
A post on TrainOdors back in early 2005 said this about the fuel-tender operation as conducted for helper service:
It was noted in the same thread that ‘keeping the helper tanks topped up’ kept the adhesion weight up. I did not see any mention of “SD70MACs” per se as helper power.
We had a thread here in 2007 which contained this very interesting observation:
[quote user=“Bob-Fryml”]
during the 1980s BN ran a series of Chicago-Seattle hotshot piggyback trains equipped with specialized power lashups. The pictures I saw us
EMD offering that option on MACs would make sense, too bad my manual or searching doesn’t confirm it to be this number series.
The NS fuel tender testing of 2019 shows two LPG BNSF SD70ACEs, 9130 and 9131, that BNSF were done testing with. The idea of these MACs having LNG pipes installed could work, except that LNG lines are a bit bigger and have different connectors, here is a picture. I came across a website from ~2005 talking about conversion of MACs for LPG. It entails lots of facilities and infastructure needed for the project. Dresser-Rand LNGo DualFuel_Locomotives (lngplants.com) To me this says that if BNSF considered LPG with MACs, but never went through, then this report wouldn’t have been made trying to convince them.
I’ve read those discussions on the BN tenders, which led me to think about tender equipped MACs. This would allow for the obvious longer run time, but I don’t think much adhesion advantage would come from full tanks when they had HTCR trucks. In 1997 when these units were built, fuel tenders were being reduced to helper service. BNSF liked the MACs much more on helper service than the SD40/60s, but weren’t used much because of no fuel tender hookups. Maybe having these 34 MACs replace the tender units on Crawford was the original goal, but BNSF decided that they could be better used in normal service, because the tender days were numbered.
As for the connectors, I’m linking a cropped photo of BN 3113 and BNSF 9809’s front pilots at the same scale. The connector plug looks the same size and shape. I also noticed that on some of these MACs the line was taken off, and replaced a few months later.
I believe that these units were in a pool for Crawford Hill pushers. The fuel tenders allowed for extended duty between trips to Alliance, NE to refuel.
I can’t say anything about the 70s and earlier, but coal hoppers after only have the main air reservoir line. Looking at locomotives then and now, I don’t see any extra lines. If there were, they would be opposite and symmetrical of the usual main air line. Usually, coal hoppers are dumped in a rotating coal dumper, but some are bottom dumped. I believe these bottom dumps are powered by air or electric solenoids. There are some exceptions, such as DMIR unit ore trains which have two lines, but those always stay together.
