HarleyTechTalk

Technical Forums => Knuck/Flat Head => Topic started by: RTMike on March 29, 2023, 08:22:01 AM

Title: Knuckle Head oil question
Post by: RTMike on March 29, 2023, 08:22:01 AM
 :fish: customer brought in a knuckle head engine that was built at another shop 11 years ago and never fired.It has STD a cases,S&S bottom end 4 5/8 stroke,Andrews cam, new style oil pump,Vulcan electronic distributor and Harley top end,got it in the bike fire it up ran good,on the fourth fire up and heat cycle it smoked on start up then after. Sitting the front exhaust port had oil in it.what it looks like to me is the oil pump is over oiling the top end and the the vacume in the engine can't keep up so the oil is running down between the valve stem and guide.
I have purchased a external oil pressure adjuster,to try out but was wondering if anyone has made a restricter for the the oil to the top end oil and had any luck.
Title: Re: Knuckle Head oil question
Post by: SP33DY on March 29, 2023, 12:25:25 PM
Way back when, it was common to drill and tap the bottom fitting on the oil line (the fitting that goes into the cam cover) and put a little Mikuni carb jet in there. I can't remember the specific jet. I looked to see if I still had some that I already modified but I can't find any. If I stumble across them I'll update.
There was a local drag racer here who removed the oil lines. Before each run he would squirt some oil on the rockers and go!