Posted by Jess [64.180.200.4] on Monday, November 09, 2015 at 23:52:47 :
In Reply to: M37CDN, 251s, and Unleaded Gas posted by Greg Coffin [67.176.56.44] on Monday, November 09, 2015 at 21:26:10 :
I have had one of my M37CDNs for over 35 yrs and it runs fine on unleaded. The 251 has hardened exhaust valve seats. A bigger issue is with stale gas gumming up the valves from not running enough.