Engine: Lark VI oil pressure check

[LeoH]

I have a 1960 Lark VI wagon, 74K, owned it for 6 years, it has always had the oil pressure light come on after starting,
and would go out at 1000rpm.

After it sitting for 6 months, and I've restarted it, it runs fine, but now I notice that the oil light comes on and doesn't go
completely out until about 2000 rpm and it's faint from 1500 rpm until then. Those rpms are basically.....

I have replace the oil pressure sender recently, it's new. I have not checked or touched the oil pressure relief valve since
I've had it due to its location and that being a PITA.

Is messing with that something that might help boost the oil pressure? I don't have an oil pressure testing gauge, is that
something I can get from NAPA or Harbor Freight and make the effort to see what numbers the testing gauge will tell me?

What else should I be doing at this point?

Thank you.

[rbisacca]

Testing gauge will tell you that you have low oil pressure. Messing with the oil pressure relief valve will not solve the problem. At 74K miles what you should be doing is thinking about an engine rebuild.

[TWChamp]

Auto Zone will lend tools for free when you leave a deposit, but Harbor Freight will sell the gauge for not too much money.

[Ross]

The bottom end of those engines is quite robust and they will keep good oil pressure to high mileages. Unless of course some disaster has taken place. If you are not getting hammering noises from down there I would guess your relief valve has got a piece of grit stuck in it holding it open. Go ahead and spend the 20 minutes to take some pressure readings then another hour to service the valve. If you remove the one timing cover bolt that is near it you won't have much trouble.

[jackb]

maybe some lifter bore wear too......put a container of STP in there and see if it makes a difference....BTW: what's the likelihood of STP being the same composition as it was in 1964 ???

[LeoH]

Thank you. I'll try the STP and clean the relief valve, it likely hasn't been done in some time, I'd bet. I figured it was likely engine repair symptoms, but
I wanted to find out if there were any other options I didn't know of. It sounds fine, no different than it has in the near 40K I've driven it so far.

[LeoH]

So. I don't have the funds to ship this off to someone to professionally rebuild. I'd like a rough estimate to break to the wife about how much this will be. With club members' help, how much am I looking at, for a do it yourself rebuild? And, understanding there will be shlepping big pieces around to shops for machine work and cleaning, about how long should I plan for this to take place? Roughly, of course. AND, I want to do it sooner, rather than later, and I do not plan to drive it routinely, but how long would I likely expect to use the car, with symptoms like this before it would fail?

[altair]

In the day there was cam shaft oil restrictors that screwed in to the oil plugs on the side of the block that restricted the oil flow to the cam and therefore forced more oil to the rods and would generally boost the oil pressure. I had used them on a Dodge flat head that is very similar in design to a Studebaker.

[rockne10]

Given that it's been running fine, if a a gauge attached at the block reads 15lb or better, I wouldn't dismiss the possibility of a restriction in the oil pressure flex hose, or the copper tube from the hose to the idiot light. That hose is a good idea to replace periodically anyway, as well as a good idea to carry a spare in the glovebox.

[rbisacca]

Given that it's been running fine, if a a gauge attached at the block reads 15lb or better, I wouldn't dismiss the possibility of a restriction in the oil pressure flex hose, or the copper tube from the hose to the idiot light. That hose is a good idea to replace periodically anyway, as well as a good idea to carry a spare in the glovebox.

There is no hose connection to "idiot light".

[LeoH]

There is no hose connection to "idiot light".

Thanks, yes, on the Flathead Six there's just a sending unit that screws into the block and a wire that goes to the idiot light in the instrument cluster.

- - - Updated - - -

Given that it's been running fine, if a a gauge attached at the block reads 15lb or better, I wouldn't dismiss the possibility of a restriction in the oil pressure flex hose, or the copper tube from the hose to the idiot light. That hose is a good idea to replace periodically anyway, as well as a good idea to carry a spare in the glovebox.

Thanks for that parameter.

[doofus]

Got it, not often driver. if oil pressure is low, new rod and main bearings and an oil pump kit will last a long, long time. a decent weekend long time frame.one drawback, you will need to drop pan and 1 main and one rod bearing to determine size. not to expensive and well worth the effort for us CASO's. Luck Doofus

[rockne10]

Thanks for that parameter.

The idiot light usually doesn't come on until pressure drops below 5 or 6 pounds. If you are on the highway, assume that is already too late. That's why I like oil gauges.

[LeoH]

Got it, not often driver. if oil pressure is low, new rod and main bearings and an oil pump kit will last a long, long time. a decent weekend long time frame.one drawback, you will need to drop pan and 1 main and one rod bearing to determine size. not to expensive and well worth the effort for us CASO's. Luck Doofus

Good to hear. There is someone in our club with a lift (hopefully he's not using it!), So that should be a help too. Not to be a CASO about it, but are the bearings, when matched to be found locally, or should I order from the Stude vendor? I'm motivated more by time saved than bearing cost.

[LeoH]

Also, what determines whether with my symptoms you just overhaul/replace the oil pump, or go into the bottom end? Do you need to open up the bottom end TO replace/overhaul the oil pump?