Flat Tappet Cam - Modern Oil for F / 2F? (1 Viewer)

[Grayscale]

There is lots of past discussion about bumping-up zinc levels in the crankcase for older, or race engines, with flat tappet cams. Since 2020, oils are still low in zinc (ZDDP), however, the most modern API SP oil gets more out of the existing zinc, by changing other additives, according to Motor Oil Geek - @42:00. Timeline of API Even the (new) conventional generic oil at the local auto store is listed as API Service SP. The question he answered after that addresses the internet-know-how of installing diesel motor oil in a gasoline engine. My understanding is that people used a diesel-formula for a higher zinc level, and maybe deposit cleaning?

Has anyone else heard of any info about API SP oils?

 

[charliemeyer007]

Oil and filters are cheap, change often. I like Energy Release. I run Shell Rottela 15-40.

If I ever get to break in an engine again I will be installing a pre-oiler. Like 90% of wear occurs during that dry start up before there is oil pressure.

 

[AussieHJCruza]

Anything with over 1000ppm of ZDDP will look after a flat tappet cam. Over this side of the pond, they're still available.

 

[Pighead]

Has anyone else heard of any info about API SP oils?

I know nothing about that or them, I just know what I like

 

[Grayscale]

I've seen a gasoline engine, on the web, that used diesel oil for a long time. Under the valve cover, it looked like it was just drove home from the dealer for the first time. That was in cold Canada; I've used a 5W-30 full synthetic during the winter, and I keep the Cruiser in the outside. There are 'all-fleet' formulas that are intended for either gas or diesel engines.

What the geek was talking about, was that diesel-formulas contain more dispersants, a kind of emulsifier, that keeps diesel deposits suspended in the oil (detergent). Dispersants are attracted to water and alcohol, which is in normal gasoline and gasoline blow-by. It changes the oil to emulsion. I'd rather some carbon-appearance on the inside of the engine, perhaps keeping the oil's detergent from holding onto moisture and other contaminants that originate from piston-ring blow-by, and let the PCV system do it's engineered function, exiting moisture and contaminants out thru the exhaust.

Any pics of tired-looking valve lifters or cam wear from a Toyota 'tractor' straight-6; I seriously wonder if the low-rev. F and 2F were delivered with serious valve springs that you might find on a SBC or racing car engines? Maybe these engines afforded a greater surface-area for the wear-spots in question, thus doing better with a poorer oil?

 

[mrboatman]

I also use Shell Rottela 15-40 T4

 

[Mark Jennings]

I also use Shell Rottela, 15-40…..in hot hot weather (> 100 outside), I think the viscosity is a bit low, but low speed, short trips is fine….

However, no mater what you decide to pour down it’s innards…..the main key, make sure there is oil in the sump, check it regularly and change it often.

 

[cstav86]

The driven racing "green oil" is pricey but good stuff, that's what I will be running in my rebuilt motor. So is the valvoline VR1. Both have high zinc and are for flat tappet cams.

 

[numby]

If I ever get to break in an engine again I will be installing a pre-oiler. Like 90% of wear occurs during that dry start up before there is oil pressure.

Same here. I keep my junk around a while. I really wish I'd fitted a prelube system on the 2F when it was rebuilt.

The driven racing "green oil" is pricey but good stuff, that's what I will be running in my rebuilt motor. So is the valvoline VR1. Both have high zinc and are for flat tappet cams.

I've been running VR1 since the motor in the 40 got rebuilt roughly 15K miles back. I've been dealing with low vacuum at idle for a while. Could be the cam has gone flat. Still diagnosing.

 

[Mark Jennings]

Here is what a 68 F ‘bump stick’ looks like with over 100k miles. Note the ‘galling’ on the ramp side of the lobe….this engine let go due to a broken piston in 2000. There were no valve issues, everything stayed in adjustment from what I remember. Oil used back then was straight 30 weight Dino blend….whatever was cheapest. I think that was my Pennzoil period, I liked the yellow bottles.

So 25 years ago there was no issue with ZDDP, or it was an unknown issue. Maybe it was known, and at that time, I just didn’t give it much thought.

 

[Pighead]

I've been dealing with low vacuum at idle for a while.

Maybe try advancing your timing a bit, see how your vacuum responds

 

[71-CRUISER]

I have put Rotella 15-40 in every F or 2F I have ever changed the oil in.

I also recommend changing the fluid and filter every 3k (if your odo works) because they are tractor engines.

 

[Grayscale]

In an outdated article in an Engine Builder article, from 2012. It suggests, that the detergents work in concert with the protective-layer deposit of ZDDP; a balance between the amount of detergents and ZDDP is critical. It also discusses a diesel-specific environment.

Still looking for a tired F or 2F cam and lifter wear reports. Without doing a complete tear-down, I know that my rocker arms have a groove from rubbing on the end of the valve stem. It could have been from oils from 20-years ago? It is approximately .003-inch deep, and I adjusted my valve-lash to account for the feeler gauge running over a worn rocker arm surface.

 

[numby]

Maybe try advancing your timing a bit, see how your vacuum responds

Thanks, I've tried that. The ball is now almost out of the window to no effect. The idle circuit seems DOA on two different carbs with one being a fresh rebuild (but done years ago). The idle mixture screws have little effect so the primary valve is 1/4"+ into the transition slot on both carbs to get a 600rpm idle. There's other weirdness like I can't run vacuum advance on a points distributor without introducing a pronounced miss that points to a vacuum leak in the advance circuit. Engine runs well otherwise but it's still pretty fresh. I need to get methodical on this and get all the basics in order - valves, timing, leaks, etc.

 

[Pighead]

Thanks, I've tried that. The ball is now almost out of the window to no effect. The idle circuit seems DOA on two different carbs with one being a fresh rebuild (but done years ago). The idle mixture screws have little effect so the primary valve is 1/4"+ into the transition slot on both carbs to get a 600rpm idle. There's other weirdness like I can't run vacuum advance on a points distributor without introducing a pronounced miss that points to a vacuum leak in the advance circuit. Engine runs well otherwise but it's still pretty fresh. I need to get methodical on this and get all the basics in order - valves, timing, leaks, etc.

Start a thread, we love stuff like this.

 

[numby]

Start a thread, we love stuff like this.

If I do it'll turn out to be something small and I'll just look dumber than usual.

 

[Pighead]

If I do it'll turn out to be something small and I'll just look dumber than usual.

Which is why we love stuff like this.
C'mon, it'll be fun...

 

[Grayscale]

Here is a new one. Check it out...
On a flat-tappet engine, generic-synthetic from the big box, seems to be better than name-brand conventional, or a few-hours-old name-brand synthetic racing oil. Apparently, synthetic dissipates heat better, and the application on the label of the bottle is relevant.