Oil Pressure Issue at startup

[SpyderMan]

The oil is 4 months old and has 2000 miles on it. The filter is a blue PF-4. It started this after the most recent change.

[Lane66Monza]

I would find something other than a Fram filter. They are the worst of all filters.

https://bobistheoilguy.com/forums/threa ... ere.24672/

[Vairone]

I would find something other than a Fram filter. They are the worst of all filters.

If I am not mistaken, a blue PF-4 is an AC Delco oil filter.

[Lane66Monza]

I was just coming back to the blue filter. Some blue filters have a poor grade I have seen but I don't which one he has. He can do the research below. But I think the filter is the issue. I would like to see the filter opened up with an aviation filter opener. Like an old manual poke and slice can opener.

Here is a link to filter comparison done by Motor Trend. It is on Facebook. It has 4 photos with the filter comparison charts, that he can look at.

https://www.motortrend.com/how-to/129-1 ... er/photos/

[vairmech]

Sorry do disappear for the weekend but I was racing! What can I say? Racing comes first! LOL

OK, the change came with the last oil change, So change the oil and filter again, cheap check.

The way the oil system works is the center of the filter is after the filter, what that means is if there is an issue with the filter media you could have a low oil pressure there and nowhere else before. That is also what the oil filter bypass valve is for in the adapter. The oil pressure switch is fed directly from the oil pump, that is why I suggested checking there and is also where my video shows it plumed in. Personally I do not like the drilled oil filter bolts, anytime I have to remove something to perform a simple task cost someone more money! There are other better ways to do things. Anyway, it sounds like you found the oil pressure switch off a little bit? I still think you need to check the pressure at the switch outlet. If you have a 6" long 1/8" pipe you can screw that right on and clear everything while you run the engine, as you saw in my video.

BTW, I could not see the last images a couple of posts ago.

[SpyderMan]

Yes the filter is an AC Delco and I will open it and see if it has any stories to tell. I see now that my photos did not take. Both of these photos were taken with the engine hot and in drive 625rpm. Ken, all they had was a 4” pipe but with coupler nut it ended up the perfect length. I have better 0-60psi gauge coming as the 0-15psi gauge pegs when cold or not hot in drive. I checked the bad gauge and it does not move until 18psi so that puts my hot idle in neutral around 25-28psi 775rpm. This is assuming it is accurate once it moves, I will re check when the better gauge arrives.

[jimbrandberg]

I'm waiting with bated breath. I decided to do our June Tech session at Corvair Minneota on oil pressure, partly due to your fascinating tale. So let's get to it, it's been 3 whole days and you almost went to the dreaded page 2...

[SpyderMan]

Well, I have an update but it is not Corvair related. On Memorial Day evening I was trying to catch my daughter who was Rollerblading, I was going at pretty good clip when the front casters on my wheelchair started to flutter like a bad grocery cart. This acted like a brake and threw me out of my chair hard. My wife came a rescued me with a lift I use to get on and off the ground. My right shoulder hurt but I thought I was ok otherwise. Yesterday when the swelling in my right leg had not gone down we went to the ER and discovered that I broke my right femur. Having a whole leg cast would be a pain for anyone but it is a real pain if you are already in a wheelchair. Looks like I could be out of commission for up to two months. getting in and out of the wagon is a trick on a good day now with a permanently strait right leg I won't be doing any kind of driving for quite a while. Let's hope I have real update before two months.

[joelsplace]

Bummer. Sorry to hear that. Get well soon!

[azdave]

I won't be doing any kind of driving for quite a while. Let's hope I have real update before two months.

Wow! Hope you can get back to tinkering and driving without more delay than expected with you injury.

I'm coming back to this thread after many more posts were added but I wondered about the filter and that it might possibly be allowing some drain-back of the oil in the plumbing which could allow air into the system that has to bleed out through the bearings during startup before full pressure is seen. At first start, the air would quickly be compressed and turn off the warning light but once that air bubble makes it to the bearings, it would probably shoot past the journals really fast and cause the oil pressure to drop for just a second, maybe enough to trigger the light for an instant. The one cold start video you posted seems to show the pressure come up to 20 PSI but then sit there for a second before it jumps to 40. I know many oil filters have an anti-drain-back valve but don't know if that might be an issue here.

[jimbrandberg]

Sorry to hear about your injury and hope you have a good and speedy recovery.
Any news on the old Suburban, was it like a '37 or something?
I saw your old blue '64 Greenbrier the other day, it's doing good.

[SpyderMan]

Sorry to hear about your injury and hope you have a good and speedy recovery.
Any news on the old Suburban, was it like a '37 or something?
I saw your old blue '64 Greenbrier the other day, it's doing good.

Jim, the 38 Suburban is in process. The trucks did not have any wood in the cab except for that cab mounts, but the Suburbans did. There is wood around the rear windows and It is complete but not usable as is. It spent most of its life in the desert so the wood is very dry and the finger joints in the corners are in bad shape but my dad is doing a good job recreating them. It will head to a real body man soon for the main body repairs. We have NOS rear fenders, running boards, front fenders and grill. My Dad is doing the work in MO where I grew up and I am helping when I visit. He keeps getting a bit distracted by buying other projects. Glad to hear the Greenbrier is doing well.

[cnicol]

Wow, Sam you are one busy guy! Except for the falling part, I'd like to see you catching your roller-blading daughter, using a wheelchair. You must be pretty quick!

Hopefully, your leg will heal faster than two months. Cross your fingers!