Snake oil for cars engine

[TheGimp]

It sure made it easy to read spark plugs though.

 

[bentoronto]

TheGimp is correct that TEL was there strictly as a cheap octane improver.... by eliminating this central nervous system poison.

Agreed TEL is bad stuff.

But minor point is that it was reputed to act as a coolant or lubricant for the upper cylinder and/or valves.

I know there was consternation among fellow owners of BMW 1961 and earlier motorcycles about the removal of lead from gas. And wondering how to address it - by using hardened valves, better valve seats in our aluminum heads, or with nasty additives.

Very sad story: the Canadian government was early off the mark to ban TEL. But the Ethyl Corp sued under some kind of unfortunate worded US treaty (maybe TEL was not yet banned in US) and the Canadian taxpayers had to cough up many millions in settlement. Sad and unfair, eh.

B.

 

[PRR]

> The tetra ethyl lead was in gasoline to prevent detonation, nothing else.

The original straight TEL caused massive engine fouling and corrosion. (Nothing compared to what happened to the early Ethyl workers.)

Ethyl did much work adding additives to TEL to null some of these problems. Maybe that, not the TEL, was allowing harder-working valves to survive. Abrupt stopping of the whole TEL package did lead to some harm in some engines (not as many as was feared). Maybe the gas companies realized that and put some of those additives back.

Viscosity and pressure: the pressure on the gauge is just to get the oil out to the bearings. Flow is part of how a 1910 engine hardly turned 1000RPM and a 1990 engine might turn 6000RPM- better cooling. (Poured to thinwall bearing technology was a bigger help.) This is mildly self-correcting because as bearing frction heats oil, the oil thins and flow rises. (So I guess the oil pump size is the pounds/minute the maker figures will carry all the heat out of the bearings.)

Inside a loaded bearing the point pressure rises over 1,000psi in the hydro-wedge. And at this pressure the oil's viscosity rises sharply until pressure comes off. The gauge pressure and can viscosity do not apply where it matters most.

Additives have made a BIG difference. All the 1960s Ford 289s I knew eventually got lame or dead from oil sludge-up with SC oils. I had a 1979 351W, same basic engine, so at 100k I went to clean the pan and replace the pump. Raised on SE oil, it was clean as a whistle inside. A later trip under the rocker cover at 160k, same thing (we had a 1967 you could not see rockers for sludge). It was running good at 238k when the A/C quit, the transmission started making funny whine, and gas price was rising (over $2!!).

Nevertheless there was a recent lawsuit saying that some Toyota engine, with specified oil and change interval, was sludging-up and ruined. Toyota represented that the owners had neglected their oil. Whatever, I understand that Change Were Made (to oil? to engine?) and the problem abated.

 

[mountainman bob]

I used leaded/unleaded gas as an example of letting the public know there had been a major change.

And no it’s not lubrication that the tel offered but the controlled flame front that mattered,
kept from micro welding the exhaust valve to the seat in the older heads without hardened seats.

Tel is one of the best defenses from pre detonation and is still used in most off road racing.

Edit....and amoco still offered high octane but with aromatics instead of lead.

 

[mountainman bob]

Sorry no ‘pre’ in detonation......b4 I get lambasted for it

 

[phase]

When big oil started sneaking the zddp out we noticed cam wear (solid lifter) on the circle track cars that never happened before (somewhere around mid 1990’s early 2000’s?)took awhile to figure it out but finally did through oil analysis then research. As long as the oil we used had 1400-1500 ppm zddp starting out it was ok.

That’s about the time we started using a product called Powerup that basically eliminated camshaft break in failures during that time on the more extreme bbc engines.

The recent Toyota issues were with the 2azfe engines, and the fix was to replace the pistons and rings after the original parts had been packed with combustion by products and burned oil.

The new pistons had larger oil drain holes in the oil scraper grooves, and an ecu reflash that offered more timing advance. No change in oil that I am aware of.
The vast majority of the cars have automatic transmissions with no ability to apply vacuum by downshifting, further contributing to the problem.

I recalll taking engines apart way back that had the sludge that was in the exact shape of the valve covers.

 

[mountainman bob]

We used moly paste for cam break in on a fresh build.

The failures I’m referencing were during use.

I can’t remember exactly but the oil we had been using dropped the zddp way down to 300 ppm without our knowledge and it took a whole season into the next to figure it out....we were blaming Isky.....Isky was blaming us, it was a stinking mess.