high idle after warm up on mechanical FI

[Woody]

Greetings to all who look here. My 70 with mechanical fuel injection starts fine now. It runs great but the idle goes up intermitantly to 2300 +- for now reason. I replaced bellcrank bushings with no change. with the throttle linkage disconnected it still revs up. It seems like the injection pump hangs up. Any one have any suggestions.
Thanks
Kevin

[Ho Hum 74]

I had the same with my 74 2.7 MFI. Do yourself a favor and check the thermostat. Above the fuel shut off solenoid on the rear of the MFI pump (facing you when you open the engine bay). You'll see a hose connecting to it from the heat exchangers. This is what partly controls richness. Take the hose off and remove the thermostat. Be careful when you open it as it is spring loaded and will shoot plenty little washers all over the place. Take out the rod with washers on it and spray them down with carb or brake cleaner. I found lots of junk in mine. Once I re-assembled the high idle issue went away.

Tristan