The Ford Barn

Ianrhall · 10-18-2015, 01:21 PM

44 flathead pickup

When I first start up oil pressure is at max, comes down as expected ad it warms up. If I drive around locally,stop start and maybe the odd 40-50mph cruise it is about 1/4-1/2 on the gauge. But if I go on a longer run at "higher" speed the needle will go right down to minimum, if I then slow right down for a while then speed up again the pressure will be restored back to a 1/4. Any thing to be concerned about? Would changing to 20/50 oil help?
Ian

Ross F-1 · 10-18-2015, 01:54 PM

You need to hook up a known good mechanical gauge and see what it says. The dash gauges are just an "indication", not real trustworthy.

That said, I had a truck that was very sensitive to throttle. Oil pressure would drop on even the slightest amount of gas, then pick up if I let up a bit. It threw a rod about 100 miles later....

Ianrhall · 10-18-2015, 01:55 PM

Oooh, maybe better not venture too far then!

ford38v8 · 10-18-2015, 02:08 PM

Ian, You didn't say what you currently use, but I assume it is 10-30 which should be fine. Your symptom sounds like your oil pickup screen is partially clogged from years of non-detergent oil. Next time you change the oil, look to see if you have the truck style pan cleanout, which will make for an easy job. If not, try fishing from the normal drain hole checking for sludge. If this is the case, you'd be wise to remove the pan for a proper cleanup.

Ianrhall · 10-18-2015, 02:11 PM

I am yet to change the oil, oil looks pretty clean (and quite thin) on the dipstick
What do you suggest, take pan off and clean out the screen, all accessible with motor in?
Ian

ford38v8 · 10-18-2015, 02:20 PM

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Check to see if you have that very large cleanout hole first. Just a guess, maybe 6" in diameter, that exposes the pump pickup. If not, you likely have just the 1 3/4" drain plug, from which you can at least determine if you do have excessive sludge.

Pan removal is a job that is easier with the engine out, but can certainly be done without pulling the engine. With pan off, you can do a first class cleanout from topside, with removal of the intake manifold.

Ianrhall · 10-18-2015, 02:23 PM

No it has the smaller one-still quite big tho!

ford38v8 · 10-18-2015, 02:33 PM

If you do the cleanout, don't just scoop out the sludge, hook up your parts washer pump with a longer hose to rinse out all that remains.

Ross F-1 · 10-18-2015, 05:34 PM

Why not drop the pan? On trucks it's usually pretty easy, and you can check a lot of stuff quickly -- oil pump, bearings, etc. and do a good cleanup if needed.

G.M. · 10-19-2015, 07:44 AM

Sounds to me like a week bypass spring in the bypass valve. Early pumps
didn't have a valve in the pump. Up until 1948 the blocks have a bypass in
the front of the valve valley. If there is a valve in the pump and the valley
the weakest spring will determine the oil pressure. To thin of oil will also
cause low oil pressure. Castrol 20/50 has been used by many people to
overcome low oil pressure. G.M.

Ianrhall · 10-19-2015, 09:30 AM

I think I'll pull the pan off and have a look. It's not causing a problem just a little un nerving to see the gauge at 0 after a few miles!!!
Ian

G.M. · 10-19-2015, 09:37 AM

Quote:

Originally Posted by Ianrhall

I think I'll pull the pan off and have a look. It's not causing a problem just a little un nerving to see the gauge at 0 after a few miles!!!
Ian

I would say it will cause a problem in time if the oil pressure
reading is true. G.M.

flatford8 · 10-19-2015, 10:15 AM

Quote:

Originally Posted by Ross F-1

Why not drop the pan? On trucks it's usually pretty easy, and you can check a lot of stuff quickly -- oil pump, bearings, etc. and do a good cleanup if needed.

I would take this route.. A "44" pickup is rare isn't it?.....MARK

Ianrhall · 10-19-2015, 11:06 AM

I've been told that it's very rare too!

Ianrhall · 12-01-2015, 12:16 PM

Is there a spring in the pump or relief value that can be changed to improve oil pressure?
Ian

cas3 · 12-01-2015, 12:22 PM

if oil seems too thin, smell it to be sure its not thinned with gasoline from a bad fuel pump

Ianrhall · 12-01-2015, 12:26 PM

I did suspect that too because I've had issues with fuel getting past the valve in the bottom of the float bowl(correct name escapes me) however the oil doesn't smell of fuel at all
I'm going to be draining the oil and removing the pan soon. How does the oil pan seal around the front pulley?
I intend to use 20/50 when I refill, is that ok?
Cold wet weather putting a stop to driving in the uk now
Ian

10-18-2015, 01:21 PM	#1
Ianrhall Senior Member Join Date: Apr 2014 Posts: 253	Oil pressure question 44 flathead pickup When I first start up oil pressure is at max, comes down as expected ad it warms up. If I drive around locally,stop start and maybe the odd 40-50mph cruise it is about 1/4-1/2 on the gauge. But if I go on a longer run at "higher" speed the needle will go right down to minimum, if I then slow right down for a while then speed up again the pressure will be restored back to a 1/4. Any thing to be concerned about? Would changing to 20/50 oil help? Ian

10-18-2015, 01:54 PM	#2
Ross F-1 Senior Member Join Date: Nov 2010 Location: NM Posts: 2,438	Re: Oil pressure question You need to hook up a known good mechanical gauge and see what it says. The dash gauges are just an "indication", not real trustworthy. That said, I had a truck that was very sensitive to throttle. Oil pressure would drop on even the slightest amount of gas, then pick up if I let up a bit. It threw a rod about 100 miles later.... __________________ '52 F-1, EAB flathead

10-18-2015, 01:55 PM	#3
Ianrhall Senior Member Join Date: Apr 2014 Posts: 253	Re: Oil pressure question Oooh, maybe better not venture too far then!

10-18-2015, 02:08 PM	#4
ford38v8 Senior Member Join Date: Jul 2011 Location: SF Bay Area Posts: 6,645	Re: Oil pressure question Ian, You didn't say what you currently use, but I assume it is 10-30 which should be fine. Your symptom sounds like your oil pickup screen is partially clogged from years of non-detergent oil. Next time you change the oil, look to see if you have the truck style pan cleanout, which will make for an easy job. If not, try fishing from the normal drain hole checking for sludge. If this is the case, you'd be wise to remove the pan for a proper cleanup. __________________ Alan

10-18-2015, 02:11 PM	#5
Ianrhall Senior Member Join Date: Apr 2014 Posts: 253	Re: Oil pressure question I am yet to change the oil, oil looks pretty clean (and quite thin) on the dipstick What do you suggest, take pan off and clean out the screen, all accessible with motor in? Ian

10-18-2015, 02:20 PM	#6
ford38v8 Senior Member Join Date: Jul 2011 Location: SF Bay Area Posts: 6,645	Re: Oil pressure question Sponsored Links (Register now to hide all advertisements) Check to see if you have that very large cleanout hole first. Just a guess, maybe 6" in diameter, that exposes the pump pickup. If not, you likely have just the 1 3/4" drain plug, from which you can at least determine if you do have excessive sludge. Pan removal is a job that is easier with the engine out, but can certainly be done without pulling the engine. With pan off, you can do a first class cleanout from topside, with removal of the intake manifold. __________________ Alan

10-18-2015, 02:23 PM	#7
Ianrhall Senior Member Join Date: Apr 2014 Posts: 253	Re: Oil pressure question No it has the smaller one-still quite big tho!

10-18-2015, 02:33 PM	#8
ford38v8 Senior Member Join Date: Jul 2011 Location: SF Bay Area Posts: 6,645	Re: Oil pressure question If you do the cleanout, don't just scoop out the sludge, hook up your parts washer pump with a longer hose to rinse out all that remains. __________________ Alan

10-18-2015, 05:34 PM	#9
Ross F-1 Senior Member Join Date: Nov 2010 Location: NM Posts: 2,438	Re: Oil pressure question Why not drop the pan? On trucks it's usually pretty easy, and you can check a lot of stuff quickly -- oil pump, bearings, etc. and do a good cleanup if needed. __________________ '52 F-1, EAB flathead

10-19-2015, 07:44 AM	#10
G.M. Senior Member Join Date: May 2010 Location: Florida and Penna. Posts: 4,471	Re: Oil pressure question Sounds to me like a week bypass spring in the bypass valve. Early pumps didn't have a valve in the pump. Up until 1948 the blocks have a bypass in the front of the valve valley. If there is a valve in the pump and the valley the weakest spring will determine the oil pressure. To thin of oil will also cause low oil pressure. Castrol 20/50 has been used by many people to overcome low oil pressure. G.M. __________________ www.fordcollector.com

10-19-2015, 09:30 AM	#11
Ianrhall Senior Member Join Date: Apr 2014 Posts: 253	Re: Oil pressure question I think I'll pull the pan off and have a look. It's not causing a problem just a little un nerving to see the gauge at 0 after a few miles!!! Ian

10-19-2015, 11:06 AM	#14
Ianrhall Senior Member Join Date: Apr 2014 Posts: 253	Re: Oil pressure question I've been told that it's very rare too!

12-01-2015, 12:16 PM	#15
Ianrhall Senior Member Join Date: Apr 2014 Posts: 253	Re: Oil pressure question Is there a spring in the pump or relief value that can be changed to improve oil pressure? Ian

12-01-2015, 12:22 PM	#16
cas3 Senior Member Join Date: Jan 2011 Location: sw minnesota Posts: 4,574	Re: Oil pressure question if oil seems too thin, smell it to be sure its not thinned with gasoline from a bad fuel pump

12-01-2015, 12:26 PM	#17
Ianrhall Senior Member Join Date: Apr 2014 Posts: 253	Re: Oil pressure question I did suspect that too because I've had issues with fuel getting past the valve in the bottom of the float bowl(correct name escapes me) however the oil doesn't smell of fuel at all I'm going to be draining the oil and removing the pan soon. How does the oil pan seal around the front pulley? I intend to use 20/50 when I refill, is that ok? Cold wet weather putting a stop to driving in the uk now Ian