Does oil weight Matter or ? (1 Viewer)

[Steamer]

I’m curious if your engine overhaul included new cam bearings. I’m just remembering what a guy at Delta Cam told me when I got my cam reground. I asked him if I should change the cam bearings while I’ve got the cam out and he said if I had good oil pressure before I pulled it, then the bearings should be fine.

He reminded me that the cam turns half the speed of the crank shaft and has much less forces on it to wear the bearings. For that reason, he said it’s not uncommon to leave the old cam bearings in.

Just wondered if yours got left in based on that logic and maybe they weren’t so good.

Also, pressure doesn’t reflect flow. It reflects resistance to flow. Might be good to pull the valve cover and check oil flow up there when the pressure is low at idle.

I ran Mobil 1, 10-40 for a lot of years and after the re-grind, I added Competition Cam’s break in additive to every oil change. (Delta’s recommendation for flat tappets). I’ve now switched to Valvoline VR1 Racing 20-50 and add a bottle of the Lucas break-in oil. I have a VDO mechanical gauge & my pressure has always been close to 60 with any oil, at any temp. At 550 rpm it drops just a few psi.

 

[Steamer]

Also, This link on “Oil Brands & Protection” is long but interesting.

 

[Dizzy]

I've seen some funky looking oil pump screens of F and 2Fs in this forum. I wouldn't hesitate to check there if in doubt,

 

[love2fly]

The cam bearing has been something that has crossed my mind several times. Unfortunately I did not get a brake down record of all that was completed during rebuild. As I had know knowledge of the engines running history before rebuild only that it was in sad condition with some broken piston rings and some other accessory problems it just could be a cam issue. I replace the oil pump on the rebuild with a factory pump.
Cheers

 

[middlecalf]

Seems like if you have a bad cam or oil pump you would have low oil pressure all the time. You don’t, just when oil is hot.

With viscous fluids (like oil) as temperature increases, viscosity decreases. And with viscous fluids in a closed system, as viscosity decreases, pressure decreases. So you’re seeing normal operation as long as your getting oil everywhere it needs to be (via inspection which is the most challenging).

 

[RWBeringer4x4]

20+ psi of oil pressure at idle seems fine to me in a tractor engine like the 2F. Again - I don't have a lot of experience with the 2F, specifically, but oil pressure ALWAYS drops when the oil gets hot and thins out. My small block idles at about 12-15psi on hot days and it's a brand new motor. As long as you're building pressure with RPM I'm not overly concerned with anything I'm seeing here. To me if the motor idles at 20PSI on a hot day, and has 35-40psi by ~2000RPM when hot I wouldn't be worried at all.

Again, no direct experience with a 2F but I can't imagine the tolerances at play are drastically different from any other motor of the same era.

 

[Dynosoar]

You can always install an oil pressure kill (safety) switch. It is a pressure sensor that will cut the ignition if oil pressure drops below a certain threshold. you would need to install a T fitting where the stock sender goes.

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Dyno

 

[78Landcruiser]

Rule of thumb is 10 lbs of oil psi per 1000 RPM to be mechanicaly safe,

so 10 psi @650 is safe,