All Small Six 170 idle and vacuum problems

[gsav69]

Hey folks. Have a 66 bronco with a 170. Bought it from an old timer who made it appear it was running well when it's not. He had it idling so high it appeared to make vacuum and ran smooth. When I get the idle down to 640, my vacuum is a disaster (9 in or some shit) and it barely runs with 14 degrees of timing. Hes added a petronix to it and I did confirm the advance works. I haven't been able to find a major vacuum leak but did find a leak out of the bottom of a brand new fuel pump and there may be a very small leak at the main shaft in the autolite 1100, if at all. No matter where I spray, I can't seem to impact the idle. I haven't worked on it in a while but want to get after it this weekend. I'm new to the Boyton Beach Florida area and haven't found a tech I'd trust yet so I'm hoping folks can offer some thoughts and ideas on things i should consider. Ill be starting with a compression test and working my way from there. Thx in advance for any help and if you know of any techs down this way, I'm open to recommendations.

 

[bmbm40]

Your Bronco may have the infamous LOM dist and carb with the SCV originally. They work together and you can't swap out either component with non matching ones. Verify what you have and see if this article can help you trouble shoot the situation. People generally remove both and go with something like DSII ignition and non-SCV carb.

Classic Inlines Ford Six Load-O-Matic Distributor & Spark Control Valve