Good afternoon everyone.. I have a quick question. I’m rebuilding a 85 gslse 13b and i just starting cleaning the housing. Once i was done I was looking everything over and found what looks like a chunk of the housing near a cooling jacket missing. If someone could give me their input I’d really appreciate it. If it is broken can I replace the house with a different one or does it have to be a 5 letter housing. This is my first engine build.

 

That is now trash. The seal will never seal correctly. I've seen some folks try and use a side seal to bridge that, but it won't work. You could fill that entire water jacket with JB or another epoxy, but sine that is near the spark plug I would not do that. I believe you can still get GSL-SE housings new. Just checked and a new GSL-SE housing is about $750.

 

To be very clear, it needs to be a 13b SE housing as the 13b is 10mm wider than a 12a housing - which is what increases the displacement. Further, it needs to be an SE housing to have matching exhaust port to your other housing. If you're replacing both housings (*recommended) during the rebuild you'll have much longer life out of the rebuild engine vs. only replacing this bad housing due to the wear pattern and tolerances of new vs. used.

Is the engine going back into an SE or something different? Depending on the chassis, you have a lot of other rotary engine options available to you.