Oil Temp 265 Degrees and Pressure Only 9 PSI -- Did Ford Say That Was OK for a 427?

[patrickt]

No, this is not an April Fool's joke, but it recently won a small wager for me.



Source: Shop Tips, Volume 1 Number 2, Ford Motor Company (November, 1963)

[4pipes]

Yikes, my oil pressure light is set to go on at 30psi. On hot days, with oil temp around 100c, it will flicker at idle.

[patrickt]

Originally Posted by 4pipes

Yikes, my oil pressure light is set to go on at 30psi. On hot days, with up oil temp around 100c, it will flicker at idle.

Well, you, too, would have lost that bet.

[1795]

Patrick,

I would have lost that bet too regarding the oil pressure It must be that the oiling system is so efficient that at 9 psi there is enough oil movement to privet total catastrophic failure? It would seem like it might be a possibility at low rpms, I cannot imagine the damage that would occur at high rpms with low oil pressure.

Where did you find that tie bit? You have too much time on your hands, go out for a drive!

[patrickt]

That is from the Ford Shop Tips, Volume 1 Number 2 (November, 1963) that Ford would send out to the dealer technicians. I think it's safe to say that the 9 PSI was at idle only. I have the owner's manual from the same time period that clearly states "occasional flickering" of the oil light while idling is normal. Old Ford techs that worked at the dealers have told me that "we would go as low as 6 psi at idle, but below that was usually bad."

[Bernica]

Wow. I would have lost the bet as well! Did that apply to all 427's? Center-oilers and Side-Oilers? Just curious..

[patrickt]

Originally Posted by Bernica

Wow. I would have lost the bet as well! Did that apply to all 427's? Center-oilers and Side-Oilers? Just curious..

All I know is what I read in fifty year old Ford Shop Tips. But if you can believe what 80+ year old ex-Ford mechanics tell you, they didn't really care much at all about oil pressure at idle, on any of the FEs. I don't think you could get any of our favorite engine builders to now say "oil pressure at idle doesn't matter" simply because it's not politically correct. I think Barry's on record as saying he starts to get concerned when it's idling down around twelve or something, but don't quote me on that.

[Bernica]

I always thought 20-40 psi was the rule of thumb. I sometimes run as high as 60!

[patrickt]

Originally Posted by Bernica

I always thought 20-40 psi was the rule of thumb. I sometimes run as high as 60!

I think you should drop your oil pan, remove your bearings, drill some holes in them, then put them back in. That will let some of that needless hi-pressure out.

[1795]

I use 20-50 and when the engine is cold it runs at about 80 psi and then when it is warm it drops to 60 psi, 40 psi at idle.

[patrickt]

[Bernica]

That's right about where I am.

[patrickt]

In all honesty, unless you had your engine basically built to 1965 specs, you can't really rely on the literature from that era. I don't know what Lykins likes to see on his bad-ass FE builds, but I'll betcha it ain't 9 PSI at idle.

[Bernica]

Growing up, I had 390, 406, 428 and 427's and was always told 30 psi hot should be the norm. That was before the tricked out HV / HP oil pumps and special blend oils, so I agree. Today's builds are a different animal all together.

[Jaydee]

That's why we usually refer to them as idiot lights. Only really made for the general public when you loose total oil pressure, the light will come on. If they made it to go on at say 20 psi, then hot oil pressure on a worn engine would come on or flicker all the time. So they made it low enough that if the oil pump broke, it would come on. Same with alternator warning lights. Unless you broke a fanbelt, a alternator can stop charging , but the light won't come on. That's why gauges are so much more important. But then most of the public wouldn't know what they were supposed to be reading.
JD

[xb-60]

JD,
"Idiot gauges"? I know where you're coming from, and I agree up to a point. I think I could never have too many gauges....but warning lights very much have their place as well.
Gauges are excellent for monitoring, but they don't tell you immediately that something is going wrong unless you just happen to be looking at the right gauge at the right time.
I broke a fan belt once (in the middle of nowhere), and what alerted me to the occurrence was the temp warning light coming on....and looking at the temp gauge showed that the water temp was at the top end of the scale (and I do scan gauges regularly).
The temp warning light was what averted major engine damage.
Incidentally, the temp warning light and the temp gauge were standard fit. I will have the same on my FIA build.

Cheers,
Glen

[Jaydee]

I really meant that only having the light won't show you what's going on. I agree that having both is ideal. Reading up on my Territory, that when the temperature goes to high, It will beep at you, then if you ignore that, then it starts cutting out cylinders, until you don't have any power. So hopefully you pull over and see whats going on. Having worked for the RAA for many years. It's amazing how many people keep driving, with the light on hoping to either get home or that things will get better by themselves, until the engine seizes up. One member had a faulty alternator, so I gave it a tap with a hammer, and it started charging. Usually worn brushes. A week later, he still hasn't bother fixing it, but kept hitting it until he put a hole in the side of the alternator.
JD

[Tim Brewer]

Agree with JD. Back in the day, it was common knowledge that if your "idiot" light came on it was generally too late. If you knew anything about engines at all, you knew enough not to wait until the "idiot" light came on to check your oil level, Even regular factory gauges in older american cars were never very accurate. We even believed that many oil and temp gauges were designed to stay in the middle regardless of what was really going on in the engine.

[CHANMADD]

Well....Mine has 20 psi at idle 900 rpm at 190 degrees .
With the high volume pump it keeps the oil flowing . Too much pressure ain't good either.Also if the oil going to the top is restricted .for solids .even at a low 9 psi , there is still enough volume going through.

[blykins]

What I like to see for my personal stuff and what the customers like to see are generally two different things.

Oil pressure takes horsepower. Most guys want to see 20-30 at idle and 70-80 at full song. I can oblige.

Just built a 409 inch Pontiac for myself a few months ago. With a standard volume pump, it was 55 psi hot, at WOT....measured at the filter.

Remember, you'll lose oil pressure from the front of the engine to the rear of the engine. Typically about 10-15 psi. Built a bracket race 408 Cleveland for a guy, it measured 55 psi at WOT crossing the stripe at 7500 rpm. That's measured at the rear of the block, opposite end of the pump. Bearings looked brand new on tear down.