kortopates

Hi Paul,

I was hoping I could pick your brain a bit.

I have a 231 with a TSIO-360GB3(1756hr TT) and it developed a fuel leak at the engine driven fuel pump.  Looks like ~$1200 to rebuild from LyCon.  I can send the entire fuel system to Aircraft Accessories for a OH price of `$2000 and they can upgrade to LB fuel system for that price.  I was planning on changing to a LB at the OH but it looks like this might be a better time to do the conversion.  If you remember I worked at Victor in the 90s and set a ton of fuel flows. 

Seems strange that a larger airflow opening in the throttle body can help the engine run cooler((Dt -20T CHT) from Ed don't know his last name author of Test Pilot Flying the M20K 231)

The fuel flow set up is interesting, 

Unmetered high (GB 45.0-49.0  -  LB 34.0-38.0)

Metered Nozzle pressure (GB 16.7-19.3  -  LB 14.7 - 16.7)

but the fuel in gal hr stays (23.0 - 24.7).  That must mean that the nozzles changed to a bigger orifice and that's why the lower unmetered/ metered fuel pressure.  Is that the way you see it? 

My question:

Have you flown behind both GB and LB?  Does the LB run cooler?

Do you know the specifics of the conversion, is the change only the fuel system?

How do I deal with the signoff?  Does a repair station need to sigh off the GB to LB conversion?

Thanks for your help

Jim