How would I know wheher a Geep has been re-engined from external evidence?
I have seen a pic of a GP9 without dynamic brakes which appears to have four exhaust stacks. Would this be a Cat engine? What happens when there are dynaimic brakes?
TIA
[8D]
4 stacks…sounds like an ICG Paducah job. I don’t think those got re-engined though. I do know that they got Dash 2 electrics, along with a distinctive “ox yoke” air filter.
Most of the geeps with CAT engines that I have seen pictures of seem to have only 1 stack usually mounted towards the front. The engines with 4 stacks are ones that have had the exhaust manifolds change to allow the gasses to flow easier, sort of like performance headers on a car.
With dynos, just cut a hole closer to the fan, and run the stack up.
And from on top.
With out dynamics, it is a little easier.
Could need 4 spark arrestors.
Cat engines usually have just one stack, and no spark arrestor. Not many Cat engined locos around.
4 exhaust stacks are a common modification, especially for those units without dynamics. Virtually all the MP GP7/9/18’s (and some GP38-2’s) had 4 exhaust stacks. Reduces backpressure in the exhaust manifold.
CAT engines usually have a smaller single exhaust stack.
Dave H.
according to www.mountainrailway.com, CPRail underwent a GP9 rebuild program. this was started with remanufacturing some parts and lowering the short hood. they also rebuilt some GP7s into GP9u specifications. CPRail uses the term GP7u for the rebuilt GP7s. the numbers are 1500-1511 and 1682-1686. 1682-1686 were rebuilt with 16-567C engine blocks. the only difference is the units don’t have dynamic brakes compared to GP9u’s, because they were formerly Toronto Hamilton and Buffalo 72-77 (71 was involved in a wreck before the rebuild program). i think the engine blocks came from retired FP9A’s.
i think the SOO line had some GP30C units that were rebuilt with CAT engines that made them look like GP35’s.
Two other GP7/9 repowering programs of which I’m aware were by C&NW and N&W. C&NW repowered 2 GP7’s with Cummins engines and were rated at 1500 HP. N&W took five GP9’s from the 500 series and repowered them with Caterpillar engines rated at 1050 HP and numbered them 100-104.
On the SOO they had CAT engins. You could tell on the GP15C. Here’s a drawing :
http://www.sooline.org/publications/drawings/locomotives/GP15C/GP15C.jpg
The GP30C was harder to tell the diffrence.
http://www.sooline.org/publications/drawings/locomotives/GP30C/GP30C.jpg
More information:
The GP15C’s were rebuilt from CR GP9’s with Caterpillar 3512 engines rated at 1500 HP. They look like a cross between a GP9(long hood) and a GP35 (cab and nose).
The GP30C’s were rebuilt from UP GP30’s with Caterpillar 3515 engines rated at 2000 HP. They look similar to most GP38-type rebuilds from NRE, MPI, etc.
All of them now run on the Twin Cities & Western/Red River Valley & Western system.
I am actually building the Twin Cities and Western GP30C and it mostly resembles a GP35 even though they are built from GP30s. As you can see from the drawing of the SOO GP30C, which is the exact match of the TC&Ws GP30c, The fans in the back are spread apart quite a bit. Well, if you look at a GP35 there is a small fan that sits between the two big fans. That needs to be removed and patched. Then the Dynamic grid needs to be remade to match the GP30C. Notice that the GP35 has a cooling fan above the grid. Leave that there and rework the grid. Then the first cooling grid behind the cab needs to be removed and worked on to be shortened. Also there are a couple of hatches on the side between the Dynamic grid and the first cooling grid that need to be added. Once all of this is done it’s very close to the proto type. The TC&W also has a sign on the side of the locomotive on one of those hatches that says they’re powered with CAT engines.
Happy railroading[(-D]
James