Re: IML: 1961 oil preasure should I be concerned - mildly

[sosmi@xxxxxxxxxxx]

The rule of thumb for oil pressure, is 10 psi, per thousand RPM. check it with a mechanical gauge. Its possible the oil pump is the problem, either worn gearotors, or the relief valve is stuck partially open by-passing oil, thus reducing pressure. As for excessive crankcase pressure, most causes have been addressed, except for the heat cross-over passage in the intake manifold, it is possible for exhaust gases to pressurize the crankcase under the intake manifold, if the gasket has failed. Ya'll have a nice day, Dave.

 

-------------- Original message --------------
From: Kenyon Wills <imperialist1960@xxxxxxxxx>

>
> --- Mark Battesby wrote:
>
> > My 1961 oil preasure gage has always on the low end.
> > It has never even read dead center. I have had the
> > car for 15 years and rarely drive it , and it runs
> > good. But now it needs to be my main and only car to
> > get around. Im curiose if the preasure is low why
> > then does oil blow out threw the breither cap .
> > Wouldnt that appear to prove that there is plenty of
> > preasure? What is the normal amount of preasure on
> > the oil for this 413 wedge moter? Als the car does
> > not ever over heat wouldnt low oil preasure tend to
> > heat the moter up ?
>
> Heat is relative to yo ur coolant and radiator, not the
> oil. Oil plays a relatively small part in heat
> dissipation in a water cooled engine, a larger one in
> an air cooled engine (such as a VW or a motorcycle).
>
> Oil pressure is relative to your oil pump's ability to
> create pressure and the sensor/gauge set that shows
> the pressure on your dashboard.
>
> You may have a weak oil pump, or you may have a gauge
> that just reads low. The only way to tell for certain
> is to put an alternate gauge on the engine's oil
> passage when it is running.
>
> The engine has one or two threaded holes at the center
> rear portion behind the intake manifold near the
> transmission. You can borrow or buy a gauge to screw
> in there to see.
>
> The oil coming out your rebreather cap has nothing to
> do with oil pressure either. When the pistons travel
> up and down the ir cylinders, the rings are supposed to
> seal as the piston compresses the air fuel mixture.
>
> When they don't do so effectively, the air/fuel
> mixture that was supposed to be compressed winds up
> partially leaking past the rings to whatever degree.
> This "air" then blows through the engine and out the
> breather cap. Since it goes down the cylinder wall,
> which has oil on it, it atomizes oil too, taking that
> out the door with it out the breather cap.
>
> The breather cap flow is an indication that your
> engine is worn and tired. The low oil pressure is
> probably due to a similarly worn oil pump. The pump
> creates pressure, and if it has loose tolerances, it
> loses ability to force as much volume or create as
> much pressure as it once did.
>
> You can replace your oil pump, but I'd suggest that
> you're past due for an engine rebuild, or at the least
> a ring & valve job with replacement of some
> accessories.
>
> Start saving now, and don't curse out the car if it
> fails on you. It's speaking to you already.
>
> ---
>
> If you are not already running 20w50 oil, which is
> thicker, you might want to. That works better than
> the lighter stuff in a worn engine.
>
> Kenyon Wills
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
> ________________________________________________________________________________
> ____
> Finding fabulous fares is fun.
> Let Yahoo! FareChase search your favorite travel sites to find flight and hotel
> bargains.
> http://farechase.yahoo.com/promo-generic-14795097
>
>
> ----------------- http://www.imperialclub.com -----------------
> This message was sent to you by the Imperial Mailing List. Please
> reply to mailing-list@xxxxxxxxxxxxxxxx and your response will be
> shared with everyone. Private messages (and attachments) for the
> Administrators should be sent to webmaster@xxxxxxxxxxxxxxxx
> To UN-SUBSCRIBE, go to http://imperialclub.com/unsubscribe.htm
>