Posted by Vaughn [23.116.56.126] on Monday, July 20, 2020 at 22:00:40 :
In Reply to: Lets talk about.. Vapor lock. posted by Jim Lee [162.158.106.87] on Friday, July 17, 2020 at 03:52:23 :
After you get the pump from MWM and install it and before you hook up the line from the tank, put your finger on the port and have someone crank the engine. If you don't feel much suction, you could have a worn cam lobe. I had a 48 jeep with the 4 cylinder flathead and it had a vapor lock issue. After checking everything to make sure nothing was clogged, I still couldn't get pressure from the pump. I knew the pump was good and couldn't figure why pressure remained low. So my Dad and thought the only thing not checked was how the arm was engaging the cam. So we did the finger thing and found the pump hardly had any suction, so I pulled the pump, welded a bead down the side of the arm that rode against the cam. After installing it, the pump had great suction and that eliminated the problem. It's a frustrating problem, stay on it and you'll get it solved.