Flathead Normal Oil Pressure
 

What should be the normal oil pressure on cmp V8 flathead engine? At idle? 2000 rpm? Cold? hot?
Cheking pressure on our F15A....

Attachment 115895
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Thanks in advance!

Flathead oil pressure
 

Ford has two types of oil pumps '49 up and then earlier. The '48 and earlier blocks have the oil pressure relief valve in the front of the valley and 20 psi running is considered good. The later pump has its relief valve intergral with the pump and can range from 80 psi cold to 20 psi hot. When installing a late pump in a '48 - block the valley relief spring must be shimmed or stretched so as not to operate before the pump relief. It is a popular upgrade in rebuilding V8s. There are even different electrical sending units for your guages ranges. Newc

Thank you very much for your quick reply.
This F15A is late 1944/45.
The electric sending unit fail and will be install a mechanical unit to make an oil pressure check.

Then again, in the 48' and earlier style pumps (as fitted to CMP's), there are also 2 different pumps.

The earlier CMP oil pump could produce a maximum of 50psi cold, and around 15psi hot. The gauge sender on the block is specific to the gauge and is stamped with the number "50" on the thread. The dash gauge reads up to 50psi (and then there are 2 versions of this gauge, a brown gauge for Cab 11 nd 12, and grey gauge for Cab 13)

Then from around 1944, a new pump with a higher pressure relief was introduced that could produce 80psi max, as Dave has mentioned above. This pump had a sender marked with "80" and a gauge that reads up to 80psi (and again 2 types, a grey gauge for commercial style Cab 13 instrument clusters, and a 2 1/4" round gauge for the later military style cluster.

Brand new Ford Oil pumps are available as modern production items, but as far as I am aware, they are only made in the post-'49 style 80 psi version (which requires the modification mentioned by Dave to use in a wartime block). I have not seen any new production early-type pumps available. These new pumps are available in either a standard flow volume or a high volume design. (Melling M19 or M15). Either will work, but there is not any benefit in running a High volume M15 in a more or less standard engine.

Note too that it is perfectly fine to use an 80psi pump in an early engine, but you must use BOTH an 80 psi sender and an 80 psi gauge with it. You can use a 50psi pump with an 80 sender/gauge combination, but never the other way around. It is also sensible to change the Bakelite timing gear to an Aluminium type if running an 80 psi pump.

As only 80psi pumps are available as new parts, I would like to see "someone" produce a brown face decal marked 0-30-80 to go on a later 80psi gauge, so that an appropriate-looking brown gauge can be used in 11 and 12 cab fords in conjunction with an 80psi pump. Anyone?

Attachment 115843 Attachment 115844 Attachment 115845 Attachment 115846

Cab 11 and 12 oil pressure gauge decal
 

Hi Tony,

The artwork looks pretty simple and straight forward. I might have a go at it. Could be a good project during lockdown. I cannot print them however as I no longer have a colour printer. Got fed up replacing expensive cartridges even when I seldom used the printer. I have a laser printer and decal paper but only print in black.

Happy to put the artwork here for others, or liase with someone to get them made. I have the later 0-80 gauge to get the background size, shape, and border correct. Impossible to scan one without bending the needle but if you could get me a photo as square on to the middle of the gauge that would reduce distortion.

Cheers,

The F15A instruments

http://www.surfacezero.com/g503/show...92424&cat=4108

Attachment 115896
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Attachment 115897
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Cab 11 and 12 oil pressure gauge decal
 

Hi Tony,

Attached is the preliminary artwork for a Cab 11 and 12 Oil Pressure gauge face. It was a good project today. Too cold for the shed.

Will work on scaling for printing and tidy up a few things but it looks OK. Will repost it when that is done.

I found I could tilt the image digitally in Paint.net so I used yours as posted and made it level.

Cheers.

Jacques,

I wish I was that good with a computer......

David

Nice job, Jacques.
My flatty has about 60 when cold and bellow 20 when hot - all at idle. If its any help.

Cab 11 and 12 oil pressure gauge decal- revised
 

Hi Petr,

Thanks, likewise David.

Here is a revised artwork for the Oil Pressure gauge. I added the border and changed the aperture to white to make it easier to see to cut out.
I also changed the colour of the numerals and scale to a light tan as best as I could guess. Always happy for "peer review" if anyone sees a need for a correction.

I tried scaling it but my black only laser printer does not allow 4 x 6 paper selection.

Here's how I have done colour decals in the past:

I buy A4 decal paper, guillotine it to 4" x 6" photo size and adjust settings on the printer for thicker paper. I practice with plain paper cut to 4" x 6" to get the sizing right with adjusting the scaling of the image. Once it looks good and the right size on plain paper I print it on decal paper. Inkjet printer decals need a light spray of Krylon to prevent the colours running when soaked in water. Laser printed ones do not need it coated.

In Australia I get decal paper from Decal Specialists in Melbourne. Order 170 gsm size which is thicker. It was about $1.70/sheet for A4. The thinner size is better for modelmaking.

It is actually fairly simple. The hardest part is getting the artwork right!

Good luck to all.

Cheers,

Those are very good decals.

I have a couple of very nice NOS 50psi brown gauges, but I can't use them with the new manufacture 80psi pumps. Ford never made brown gauges with 0-30-80.

I need a brown decal calibrated 0-30-80 that I can stick onto a late 80 psi grey gauge to use with an 80psi pump.

I don't have your graphic skills, but a complete brown decal with these numbers:

0-80 psi oil pressure decal
 

Hi Tony,

My misunderstanding.

So from what I now understand the 0-30-80 psi brown gauge face needs to be reproduced because they don't exist?

If I modify what I have done on my 0-50 psi face to coincide with a 0-30-80 psi face that would do the job? As long as the max needle deflection shows 80 psi.

It would be an easy mod. I used a NOS 0-30-80 psi face for my dimensions and registration so a bit of moving of numbers and a best estimate of the style of the "3" and "8" would do it. Also adjusting the scale if required for the 30 psi position.

I will see what I can do.

I know it is a bit subjective but how does my colour choices look compared to an original brown face gauge?

Cheers,

Correct.

The only type of new bought oil pumps that are available are 80psi versions, you can no longer get a 50psi pump. So, for a 11 or 12 cab you need a gauge which will work with an 80psi pump and sender that looks the part in the "Brown" gauge cluster. There are lots of Grey 80psi gauges available NOS (and even postwar gauges up '53) that can be used with an appropriate decal.

Colour looks good, maybe needs to be a touch darker.

Position of the "30" is in the centre.

Style of the 30 and 80 are drawn from the 1940 100Mph speedo.

Fonts for oil pressure gauge
 

Hi Tony,

You beat me to it! Just remembered I had a photo of an earlier speedo I sold which I was going to use for the style of numerals.

Thanks for that photo. Better than mine and should be easy to make a similar looking oil pressure gauge face in keeping with the period.

My misunderstanding was a need to convert the later 0-80 psi gauge to the earlier 0-50 psi. I guess there still is a need in view of the availability of the later gauges if people still run the 50 psi pumps.

Note: I have attached 0-80 psi gauge face to resemble an earlier 0-50 psi face. Think I got the "3" and "8" OK from the speedo photos. Not sure if the top of the "8" has some fill in but it can easily be changed. I darkened it slightly over previously posted versions too.
I found by scaling this photo to 25% before printing, it matches my later 0-80 gauge face perfectly.

Cheers,

Sorry to hi-jack your thread in other directions.

I understand from your earlier posts that there is currently some difficulties in Argentina with overseas payments, but it is possible to readily purchase brand new 80psi electrical senders of the type used with the CMP V8. Despite the funds transfer problem, would this not be easier than converting to a mechanical gauge?

https://www.ebay.com/itm/48-49-50-51...d462%7Ciid%3A1

Hi Tony
Thanks for the Ebay link! :thup:
The electric gauge will remain in place on the dashboard. Seems to be original.
I will add a mechanical oil gauge to control the pressure.
The point is what are the proper pressures in ford V8 engines. This engine is SN 5G#####F
Now the engine have 80 PSI cold , and once warm it drops to 65 PSI with the mechanical oil gauge.
Here is winter. I don't know how the pressure will be in summer ...