Oil pressure mystery

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Michael Keller
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Oil pressure mystery

Post by Michael Keller » Tue Apr 03, 2018 2:50 am

I have a WC-12 with a factory rebuilt 230 engine. The oil pressure appears low according to the gauge. How low? The gauge has markings for 40 and 80 psi, but the needle seems to hover down around 10-15 psi.

I have taken the block to gauge tube off and it is clear. I have replaced the gauge. And I have confirmed that the pressure at the block is good. I have driven it in parades and to other local events. The engine runs great.

What is going on with the gauge? Could the gauge be inappropriate for the 230 engine? Anybody have any suggestions?
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Re: Oil pressure mystery

Post by artificer » Tue Apr 03, 2018 3:41 am

Mechanical gauge....check any flex line between the block & dash gauge.
Plug a test gauge straight into the engine block to get an accurate reading. If good that will tell you there is an issue between there & the dash gauge which may be a possibility also.
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Peterdodge6volt
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Re: Oil pressure mystery

Post by Peterdodge6volt » Tue Apr 03, 2018 11:15 am

Hi
I done this many times on dodges.
You have change the oil gauge so it's fine,

Are you oil line to oil gauges has flex hose if not.

Before I tell what the problem is.
Need to know how much pressure psi on cold start and how much pressure psi on hot.

Another thing will your engine was is runnin and check the temp gauge at 140F hot running and straight away check if the oil pipe filler where you fill up oil in the engine, check if there is no smoke coming out when you rev high rpm next to the carby .
When you rev high rpm watch if the smoke is coming out of the oil pip filler breather.

Once you turn the engine off check the oil pipe filler if there lots of steam smoke coming out.


When was the engine last rebuild.

Peter

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Re: Oil pressure mystery

Post by Michael Keller » Wed Apr 04, 2018 1:53 am

What is the normal oil pressure for this motor?

A gauge with 80 psi on it seems pretty excessive. Motors with pressures that high were not available until decades later.

The block to gauge line is a solid tube; no flex tube.
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Re: Oil pressure mystery

Post by Ernie Baals » Wed Apr 04, 2018 4:31 am

Go with a 0 to 80 gauge
My WC4 starts around 60 lbs pressure and runs all day long at 40 on the road and 20 at idle
Ernie
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Peterdodge6volt
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Re: Oil pressure mystery

Post by Peterdodge6volt » Wed Apr 04, 2018 11:18 am

Ok so it's not flex hose.
Oil pressure on cold start is 60psi and hot 20psi that's the original pressure it should be

My 1942 dodge T215 does the same as yours 90psi on cold and 10 psi hot with a replace pressure valve springs , before the original oil pressure valve spring was 50psi cold and 0psi hot I already replace the oil valves and I believe it's the oil pump that is weak.

My other 2 dodge shows 60 psi cold and 35 psi hot.

To replace oil pressure relief valve springs. It located next to the dip stick, once you look at the dip stick on side next to the dip stick is a big bolt, that is the relief pressure valve springs, you will need to replace valves springs.

One thing did you have any steam smoke coming out of the oil pipe filler breather when the engine is turn off striaght away on hot.

Let me know

Cheers Peter

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Re: Oil pressure mystery

Post by Peterdodge6volt » Thu Apr 05, 2018 12:06 pm

Michael

If you have smoke steam coming out of the pipe oil filler breather when the engine is turn off hot.
The steam that's is coming out is coming from the connecting rod if the connecting rod has a space on both side of the cranke shaft like between 1 to 3 cm that's most likely for oil shortcut for oil to come out easly and splash on the very hot crank shaft and can start making steam smoke and lost oil pressure on hot.
so far I seen about 12 early and late dodge with T215 , 230 engine with 80 psi cold start and 10/0 psi hot and some of them steam smoke from the pipe breather.
So far I seen to any late dodge and few early with T214 , 230 engine with 60 psi cold start and 20/40 psi hot.
I have not yet never seen a T223, T211 yet in Australia.



Cheers Peter

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Re: Oil pressure mystery

Post by Michael Keller » Fri Apr 06, 2018 1:11 am

I took the oil line off at the block and installed a gauge. I had 12 psi cold, 12 psi warm, and 12 psi when accelerating. 'Makes me think it's the pressure relief spring so I ordered a new one.

This is a factory rebuilt engine with only about 4 or 5,000 miles on it. It doesn't seem that the problem is with worn crank bearings, etc.
1943 M15A1 Autocar halftrack (restored)
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Re: Oil pressure mystery

Post by Peterdodge6volt » Fri Apr 06, 2018 1:39 am

When you took the oil line of and put the gauges in it did you make sure nothing blocking the oil gauge little hole in the gauge.
I had few guys told me they put gauges in it and nothing happen no psi and I told them if you screw the gauge on the block the end of the gauge is touching inside end of second wall of the block.

The steam that's comes out of the pipe breather means worn out or wrong connecting rod, or small connecting rod.
The connecting rod must next to crank shaft with tiny cap, if it has a between 1/3 cm cap on crank shaft, The oil will take short cut from crank shaft when hot and lose oil psi on low rpm.

My engine came out of the factory rebuild, and was in the wooden crates box when I bought it from US,
And install last year, and first start and turn it off steam coming out, I pull sump off and discovered they put and early small connecting rods with cap on it, so far I done 3,000 KM on her with no problems. All the compression is 120 and number 6 was 137. I have Stretch the spring little long measure with a ruler, put back in it and no problem, 65 psi cold and 25 hot

Make sure you don't order power wagon, civilian and farco flathead dodge valve springs parts they most likely to show 50 psi on cold and 10 psi on hot If any one has that showing on the civilian gauges It will do the same on military gauges.

The original war time psi for later dodge is
60 psi cold start
20/30 psi hot.
40/45 high rpm
Cheers Peter

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Re: Oil pressure mystery

Post by Michael Keller » Tue Apr 17, 2018 1:31 pm

A little history here:

This engine is a factory rebuild. It was installed about 10 years ago and driven daily for about 5 years and 4,000 miles. Then the owner died and the truck sat for 5 years. I bought it and restored it.

The oil pressure gauge is good and the oil line is open and clear.

The pressure relief cup is 5/8" in diameter and the spring is 1/2" in diameter. The length of the current spring is 1 7/8".

Vintage Power Wagons provided a replacement spring that is 2 1/4". There is no way to install this without some kind of spring compression device.

I did re-install the original spring with a 1/8" shim to further compress the spring and increase the resistance to the oil pressure. There was no improvement.

It is unlikely that this is a bearing problem given that there is low mileage on a factory rebuild. But it could be a crank bearing problem.

I doubt it is an oil pump problem because when they go, they go completely. I still have 10 PSI cold, idling, and high rpm.

The oil pressure plunger is free and clear and oiled and slides smoothly. I can tell from cleaning the barrel with solvent soaked Q-Tops that there is a ring in the barrel that the plunger sits against nicely.

So what the heck is going on her? Do I have the wrong spring? Or could it actually be the crank bearings causing the low oil pressure?

HELP!
1943 M15A1 Autocar halftrack (restored)
1941 Chevy dump truck (restored and sold)
1978 M416A1 Quarter Ton Trailer (for sale)

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Re: Oil pressure mystery

Post by Peterdodge6volt » Tue Apr 17, 2018 5:28 pm

Hi
Ok you change the pressure relive valve springs interesting :?
Ok maybe 5 options
.
1) Oil pump dying.
2) cranks shaft bearings worn out
3) front timing little pipe shaped and can take short cuts.
4) crack inside somewhere in the oil line casting block.
5) oil floater blocked the one which drink oil into the pump and through all the engine and out back to the sump.

I suggest you do first pull the pan off and check first if the oil floater is not blocked or floater arm is stuck right up away from oil in the pan. it can sometimes get stuck right up or half way during the hard bump when driving.
If it's fine then before putting the pan back check for cracks inside block caster where the oil line is if not cracks then go on oil pump.

Cheers Peter




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Re: Oil pressure mystery

Post by Michael Keller » Wed Apr 18, 2018 2:44 am

I am curious about how this pressure relief device works. There is a horizontal hole in the cup that must function in pressure relief. How does it work?

The barrel that contains the spring and cup seems to have a ring at the bottom, or at least as far in as I can feel with Q-tips. I do not understand how compressing the spring and pushing the cup up works to relieve the pressure.

Also, it's curious that the 2 1/4" spring appears to be too long to install. I'm wondering if I have the cup installed deep enough in the barrel. Should it be installed below the ring instead of above of the ring?
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Re: Oil pressure mystery

Post by Michael Keller » Mon Apr 23, 2018 1:07 pm

Okay, the problem was the oil pressure relief spring. 'Got the right one installed and I have 60+ psi on start, 40 psi idling cold. Probably 25 psi hot and idling but haven't gotten it hot on the road yet.

Mystery solved. Thanks for all the help.
1943 M15A1 Autocar halftrack (restored)
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1978 M416A1 Quarter Ton Trailer (for sale)

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Re: Oil pressure mystery

Post by Peterdodge6volt » Mon Apr 23, 2018 1:26 pm

I knew it was the relief valve springs like I said earlier,
Well done Keller, but I think when you go for a drive, for 30 minutes ,make sure the engine is hot enough and when you stop, oil pressure should drop between 15 psi / 25 psi that's is normal,

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Re: Oil pressure mystery

Post by TopKick » Thu Jun 07, 2018 7:09 am

I am having the same issue with the Hercules JXD engine in my M3A1 Scout Car. I have concluded with similar testing that I must make a manual adjustment to the oil pump as that’s where the oil pressure relief spring is. I’m glad I found your post. 8)
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