Posted by John W. S. son of John S [172.70.34.171] on Friday, November 19, 2021 at 11:17:49 :
In Reply to: Mileage? posted by DDD [172.70.211.26] on Thursday, November 18, 2021 at 18:29:24 :
I would pull the spark plugs and give them a read; you can tell a lot about an engine that way. If the plugs show super rich burning then you know you are getting too much fuel and will have to determine why. Could someone have drilled the jet at some point in the history? Maybe a passage is clogged, float set too high, low vacuum not allowing good atomization, etc. Where is your heat riser set? Maximum intake heat is a serious exhaust restriction... If the plugs are good check your rolling resistance. Are your tires aired up enough? We ended up with tight steering on a truck once caused by the front tires only having about 5 psi in them. They did not look low, or even drastically different once aired up but the steering was night and day. Have you checked your oil for a leaking fuel pump?
Tough to guess from where I am. Do some testing and checking and you'll find the culprit.