13 August 2018

FM-300R on a L1B5 sump

This is a post that is completely out of order as I forgot to publish it when I was working through this fit up. I have a Lycoming Thunderbolt IO-540 with a cold air sump off of a L1B5. when trying to put the FM-300R onto this sump I ran into a bit of a snag. i.e. the sump is in my way!

As you can see here I have about an inch and a half up or out that I need to get in order to get things to line up. I think the BPE cold air sump has a very angled forward face to it that allows this fit up to work.



No real big deal here. This is a standard problem which many places sell spacers for just this problem. In my case I called Don at airflow and ordered a 4 degree spacer. I figured this would do the trick. So close!!! I am about 1/8" from fitting.If you look at the top corner of the spacer you will see it pulled away from the sump because of the top of the servo contacting the sump.



I have the servo on upside down here just to take a photo. This brass hex (the adjustable jet) is what is contacting the sump. I did contemplate just taking the 1/8" off of this hex. Also, Don had mentioned that we could remove the adjustability out of this...


I went back and forth with Don though, and Jeff Schans shipped him out a sump to work on some fit ups. Don agreed to help prototype a new bracket that would push the servo out the 1/8" while also giving me a place to mount up the linkage cables.

Presumably the straight spacer could be pulled back closer to the sump, but I am not sure that buys you any cowl clearance because the straight spacer will be pushing the servo inlet closer to the cowling.


1 comment:

Thor's Hammer said...

Really interested on how this all turns out, as I'd like to do the same engine and cowl. Thanks for the detailed pics, keep it up.

Question - that 300 throttle body - is that a pretty standard selection given this engine's performance? I thought that was like the super high performance model.
-Josh