All Small Six oil pressure problem?

[2501972F100]

My truck has a 250 inline six and I have not started it for 2 weeks. It's been cold outside here in Indiana. When I started it today the oil pressure shot up like you would expect with the cold oil but after a minute the pressure fell to less than 10 psi and I could hear a ticking in the valves. Usually it holds 20 psi warm. I let it run and warm up, then shut it off. I thought maybe warming it up would unfreeze something. About 2 hours later
I went out and restarted it hoping the oil pressure would be back but no dice. Still showing less then 10 psi and I tend to believe the gauge because of the ticking? It's a mechanical gauge. I am not that familiar with these engines. Any ideas? Anybody ever had this problem? I think the oil pump is still working because it does move the needle of the gauge.

 

[bubba22349]

What are you using for oil? You could try maybe using a thicker muti grade oil or somthing like a can of Restore to boost the viscosity some. The oil pump pressure relief Valve might be stuck open from the cold and maybe some sludge or varnish. Other than that it's going to be hard to say without opening it up and having a look.

 

[MustangDadDrake]

I might be experiencing a similar issue, what ended up happening?

 

[78250F100]

The next time I drove it the oil pressure was back to an acceptable #. Yesterday I drove it and the oil pressure was all over the place. As I would rev the engine to take off from a stop the pressure would rise as you would expect then when you were cruising along it would drop uncomfortubly low only carrying 8 to 10 psi going down the road. I put some new valve seals on it last fall and I'm now wondering if maybe I should pull the oil pan and check the pickup screen.

 

[78250F100]

What are you using for oil? You could try maybe using a thicker muti grade oil or somthing like a can of restore to boost the viscosity some. The oil pump pressure relief Valve might be stuck open from the cold and maybe some sludge or varnish. Other than that it's going to be hard to say without opening it up and having a look.

How do you access the relief valve? Do you have to pull the oil pan?

 

[powerband]

You could start simple:

... as mentioned, before major work you could change out the OIL FILTER and use new oil - maybe something like 15/40W ( Rotella is popular) or similar. I had similar varying oil pressure and after changing out to new filter and upping oil viscosity the pressure returned to acceptable range.

( sure to 'raise flames' but it was a Fram filter that I swapped out for a Purolator and never again use Fram ).

... also Rotella T4 has some Zinc in it still and I add a ZDDP supplement with oil changes and still a lot cheaper than VR1 .

 

[bubba22349]

Lol I will never ever ever use the standard Fram oil filters especially on these Ford six'es (or anything else of mine) because they don't have an "Anti Drain Back Valve" in them it's pretty important to have them for a Ford six engine with the way the oil filter is mounted Horizontally. Without the anti drain back valve the oil drains back into the oil pan in a short time after shut down and you will have a dry start up until the engine builds oil pressure again. The better oil filters for our Ford Six'es are the Motorcraft, Wix, NAPA, Purolator, that are all much better made oil filters plus they have the anti drain back valve, and as Powerband stated above it could be just that simple. Before you change the oil you might run some flush through the engine that can clean the oil pick up screen and the oil pumps reassure relief valve as well as any sludge build up in two to three oil changes. I like the Justice Brothers engine flush for this. Yes you would need to pull the pan to get access to the oil pumps pressure relief valve, and or the rod and main bearings to but X2 yes try those other simpler things first. Good luck

 

[MustangDadDrake]

I am glad I read this post and I hope this isn’t considered hijacking. I replaced my pump and screen with the help of this forum almost a year ago. I started the car up and got 40psi at my direct mount gauge. Then after driving a bit I noticed my gauge in the dash would drop but I thought it was a faulty gauge because I saw 40psi on the direct mount. But I did hear some slight ticking. so because of this post I went out today and let the engine completely warm up and then the pressure started to drop all the way to 25psi.
I haven’t changed the oil since I replaced the pump and screen. If I can find this justice brothers stuff I’ll use that if not I’ll grab some MMO. Then change the oil.

I currently have the motorcraft filter with Lucas oil classic car oil 10w-40.

worst case I have to take the pan off and make sure everything is installed correctly.

question: I do have some leaks at the bolts would that cause the slow drop in pressure? Not in the front or rear, it’s like the 10ft/lbs wasn’t tight enough for those bolts, so I have been slowly tightening them to see if the leaks go away.

 

[bubba22349]

Hi MustangDadDrake, Justice Brothers is a Sountern California company I think they are still in Duarte Ca. so you should be able to find it easy somewhere in your nearby area, others can also get it online.

Automotive - Justice Brothers

Automotive ProductsEngine Oil ProductsYour engine is the heart of the vehicle.The team at Justice Brothers have used their experience to develop and formulate products that help your engine operate at it’s peak and last longer. Cooler, smoother and quieter operation are part of what we strive...

justicebrothers.com

No that little bit of oil seepage coming from the oil pan bolts won't cause any lower oil pressure. 10 PSI is considered safe at idel RPM's running at 25 PSI isn'to bad 45 to 50 would be great. Main causes of low oil pressure is to much Rod and Main bearing clearance from wear or crankshaft Rod or main bearing journal wear or damaged from trash (sometimes a new set of bearings will fix it or a High Volume oil pump can be installed to pump more volume of oil and pressure. On real high Milage engines the cam bearings can also be worn having to much bearing clearance measureing or using plastic a gauge will help you find that out. One other thing that can cause momentary drop in oil pressure on our six'es is a lack of oil in the oil pans sump this can often happen during a fast take off, or stop, and or aggressive cornering. This happens because there isn't any baffling at the front, sides, and rear of the these stock sump oil pans to help keep the oil around the oil pump pick up tube, but the baffling can be added fairly easy to give you this added protection. Best of luck on your car projects.

 

[chad]

how long have U had it run 250? No indication. Takes 10 min to warm up. Don't trust ur dash guage as much as ur ears, still...verify. Put a different gauge on it, easy way, right there, like Dad. Also make sure the 'clack' is top end. ID where the sound is coming from accuratly (hose to ear, v/c off, etc - if U need to).
(Jacks lead threads away frm OP's Q, dad. Bolts need specific tq, U can look up.) https://fordsix.com/ci/Tech.html

 

[78250F100]

I've been driving my truck occasionally, not everyday but 2 or 3 times a week. I just drove it early this week and happened to look down at the gauge and wasn't happy with what I saw. It could use an oil change, but I'm tempted to just pull the pan to satisfy my curiousity. It's fairly easy to access in my 4wd truck. I'll report back once I get around to it.

 

[chad]

"...how long?..." is a clock kinda thing. Anyway seems like over 10 min. U like a guage barrow @ local big bx store, open hood remove sender screw into block @ that "oil tap hole"? /Or/ slide under, wrenchabuncha lill nuts out, etc, etc? I listed my choice above. Do U know sound is from rockers/lifters? not bottom end...

 

[78250F100]

I ended up pulling the pan and pump. The pressure relief valve would move but it didn't appear that I could take it apart and clean it. It was sealed in with a plug. The pickup screen was fairly clean and the pan only had minimal sludge. When I took the pump apart if definitely had some wear so I decided to replace it. After everything was cleaned and put back together my oil pressure has returned strong and steady. Thanks for the ideas!

 

[bubba22349]

So while at my local NAPA dealer picking up some parts tonight they had this display set up of a number of different oil filters cut open starting on the top left is a NAPA Gold / these are also same as the Wix since they make the NAPA oil filters too. Since we were talking about oil filters a short while ago I though I would post some pictures of the insides of the different oil filters since they already did all that work cutting them open and making that display. I had been invited to a class on oil filters as well as many other things at the local NAPA dealer in the central Calif. area back in the 1980’s since I took care of a fleet of trucks and equipment for several contractors, this is like I seen and learned about oil filters back then.

 

[65coupei6]

So while at my local NAPA dealer picking up some parts tonight they had this display set up of a number of different oil filters cut open starting on the top left is a NAPA Gold / these are also same as Wix since they make the NAPA oil filters too. Since we were talking about oil filters a short while ago I though I would post some pictures of the insides of the different oil filters since they already did all that work of cutting them open and making that display. I had been invited to a class on oil filters as well as many other things at the local NAPA dealer in the central Calif. area back in the 1980’s since I took care of a fleet of trucks and equipment for several contractors, this is like I seen and learned about oil filters back then.

In the past I only used Motorcraft or Wix because of the spring valve shown in the picture. Never had a chance to use Napa Gold.

But for the last 10-15 years I have only used Pure Power on the Mustang. They are expensive but it is a lifetime filter.

Lifetime Filters For Oil, Fuel, And More - PurePower!

Since 1995, PurePower! Lifetime Filters Have Set The Standard For The Industry. Made In The USA, PurePower! Filters Are The Best You Can Buy!

www.gopurepower.com

I now only use Mobile 1 15w-50. This weight works perfect in California/Neveda where I drive the car the most and it has zinc. These two items together give me great/stable oil pressure.

 

[bubba22349]

Hi Marco, those look to be a very good oil filter.

 

[wsa111]

I always run the large oil filters for a 5 QT. oil change. I also use Brad-Penn Racing oil 10W-30. It has all the zinc & phosphorus & detergent for street operation. It is Semi-Synthetic.