The Ford Barn

ppower · 07-30-2015, 06:40 AM

I have a Ford Model A engine fitted in a light sports car. Because of the limited radiator size I use Evans waterless coolant. The coolant temperature is 220°F to 300°F (the coolant is good to 360°F).
I have recently fitted a Snyder 6.5:1high compression head. The coolant temperatures have not changed. The improvement in performance is impressive, particularly the high bottom end torque.
I was concerned about pre-ignition, so I use the retard lever at low revs.
However after running at 3000rpm for about 10minutes I lost power. The power returned. A few days later I repeated the high speed run, and again lost power accompanied with a tapping noise. I stopped, and the engine was seized. When it cooled everything seemed OK. I drove it again and after a few miles at lower revs, a rod came through the side of the crankcase.
The paint on the cylinder barrels below the water jacket has gone brown. The land above the top piston ring in number one cylinder has mainly disappeared. The big end cap on number four seems to have been pulled off (one stud pulled off and the other has its threads stripped, but it is not bent). The top and bottom rings are seized in number four cylinder. Number four big end journal has turned blue. I have not yet removed the other three pistons.
In my anxiety to avoid pre- ignition I seem to have restricted the advance to 24° BTDC. Could this be the cause of the failure? Or am I unreasonable to expect to be able to run at a constant 3000prm with the original gravity and splash lubrication system?
Thanks for any help you can give me.

07-30-2015, 06:40 AM	#1
ppower Member Join Date: Jul 2015 Location: England Posts: 37	Engine failure - high speed running I have a Ford Model A engine fitted in a light sports car. Because of the limited radiator size I use Evans waterless coolant. The coolant temperature is 220°F to 300°F (the coolant is good to 360°F). I have recently fitted a Snyder 6.5:1high compression head. The coolant temperatures have not changed. The improvement in performance is impressive, particularly the high bottom end torque. I was concerned about pre-ignition, so I use the retard lever at low revs. However after running at 3000rpm for about 10minutes I lost power. The power returned. A few days later I repeated the high speed run, and again lost power accompanied with a tapping noise. I stopped, and the engine was seized. When it cooled everything seemed OK. I drove it again and after a few miles at lower revs, a rod came through the side of the crankcase. The paint on the cylinder barrels below the water jacket has gone brown. The land above the top piston ring in number one cylinder has mainly disappeared. The big end cap on number four seems to have been pulled off (one stud pulled off and the other has its threads stripped, but it is not bent). The top and bottom rings are seized in number four cylinder. Number four big end journal has turned blue. I have not yet removed the other three pistons. In my anxiety to avoid pre- ignition I seem to have restricted the advance to 24° BTDC. Could this be the cause of the failure? Or am I unreasonable to expect to be able to run at a constant 3000prm with the original gravity and splash lubrication system? Thanks for any help you can give me.