BuildCraft version: 7.99-23
Forge version: 2824

When disabling the Redstone Engine (or all engines in my case) several issues appear:

• The Redstone Engine can still be crafted, although the recipe is not shown in JEI
• Placing a Redstone Engine will put an undefined/invisible block into the world that does nothing but has collision.
• The Pipe Pulsar can no longer be crafted (if the Redstone Engine was correctly impossible to craft). I suggest adding an alternate recipe in this case.
• Effectively there is no way to get fluids out of anything, as pipes seem to exclusively work with Buildcraft Engines. I expected that other power suppliers would work as well.

Unfortunately that's due to how engines are implemented - they have a single base block, and then store the other engine types in that block. So you'll need to also disable the engine block itself as well if you want to actually remove all of the engines.

Adding another recipe for the pipe pulsar does seem sensible.

Currently forestry engines can create buildcraft power, or you can use a "Power Adaptor" pipe pluggable to accept power from kinesis pipes. However other than that I don't really consider it to be a problem - obviously if you disable everything that can generate buildcraft MJ then it is impossible for anything to consume buildcraft MJ to function.

In earlier versions Buildcraft would also accept RF as energy, which doesn't seem to happen anymore, at least not with the wooden pipes. I even tried to add a power converter plug the put attached an Immersive Engineering wire (which is usually compatible to everything), but the wooden pipes would not want to function.

Yes, as of 7.99.x buildcraft moved away from RF to MJ.

A questionable decision, as it only causes inconvenience to players without actually adding something, like in my case. But that's outside of the scope of this bug report.