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usered 05-19-2013 08:13 AM

High oil pressure
 

I'm running a newly rebuilt model B with inserts. Its running I think a very high oil pressure of 15lbs. Lots of oil being leaked from the front main around the crank. Is this too high of oil pressure, what would cause this?

midgetracer 05-19-2013 09:22 AM

Re: High oil pressure
 

This is about right for a B engine when cold. B engines have presurized mains. The front seal leak is a problem... probably needs a new seal. B engines tend to leak more than A engines, especially until the rings seat. Also make sure that you have the larger B type oil fill tube.

Benson 05-19-2013 10:44 AM

Re: High oil pressure
 

My fresh rebuilt (4500 miles) stock B runs about 15lbs cold.

2. Hot with 20W50 oil - AT A SLOW IDLE it is 2-3 lbs.


3. about 8-9 at 45

Bob C 05-19-2013 12:29 PM

Re: High oil pressure
 

Is the oil slinger installed?

Bob

Purdy Swoft 05-19-2013 12:45 PM

Re: High oil pressure
 

A modern style front seal could be the cause of the leak. I always use the original type rope front seal, they are easier to remove and replace. If the shank of the crankshaft pulley isn't PERFECTLY smooth and round, the modern style front seal will fail quickly.

Cajun 05-20-2013 08:32 AM

Re: High oil pressure
 

I installed a Dan-4-Banger oil pump on my B engine. It runs at 60 psi cold and then drops down to 38-40 when warm. It has a Butz rear seal and a modern front seal. There are NO leaks. I would look into the front seal. There are several types of "modern front seals".

usered 05-20-2013 09:39 AM

Re: High oil pressure
 

Thanks everyone, you've given me several things to check out. Sounds like the oil pressure maybe ok, 5 - 10 cold idling and up to 15 running 45 or 50 hot. I'll let you know what I find out on the front seal.

Jim Brierley 05-20-2013 10:17 AM

Re: High oil pressure
 

I think your pressure is higher than normal. The stock B's that I have run all had 3-4 lbs. cold at highway speeds and less than 1 lb. hot. Some rebuilders plug or restrict the hole at the front of the galley to gain pressure. This works but that hole is there to feed the dipper tray so you now have less oil going to the rods, not good!

usered 05-20-2013 02:09 PM

Re: High oil pressure
 

1 Attachment(s)
Kinda getting conflicting info on what the oil pressure should be.

Not sure it makes a lot of difference but this model B engine is not stock. Inserts, balanced crank, lighten flywheel, 3/4 cam, larger values, high compression head and dual plugs per cylinder, tube header, electronic ignition and dual 81's. See picture below.
Got a call into my builder top get his thoughts on it.

Thanks everyone

V4F 05-20-2013 02:47 PM

Re: High oil pressure
 

damn nice motor ! i run an "A" motor with a V8 pump . 20# all the time . a small leak at the rear ............. pump pre set at 20# at all rpm

usered 05-20-2013 02:58 PM

Re: High oil pressure
 

Sometimes its the simplest solution! I changed the oil pressure gauge, I had an old APCO gauge I was using and I swapped it for one out of one of my other cars and now its 3-4 lbs cold and 8 - 10 hot.

I did talk with the builder and he said that he had used a rope type front seal. Its still leaking more then I would like so I still have that problem to deal with.

V4f maybe PM me I'd be interested in what you did on your pump.

Benson 05-20-2013 03:43 PM

Re: High oil pressure
 

Note the Model B engine that I referred to above in post #3 is stock and has the oil pressures as listed above.

This engine was stock and had standard bore, pistons, Ford valves, std sized rods and mains when I rebuilt it.

I also have seen B engines with very low oil pressure, which I think is caused by using the wrong oil pump shaft.

The low pressure is an indication of insufficient oil flow to the dipper pan and the rods through the large hole in the front of the oil galley. That is ... not enough flow to keep the dipper pan full of oil at higher engine speeds.

The A engine gets HP at 2200 and the B engine at 2800 so more oil flow is needed to keep dipper tray full of oil.

On this engine all the holes in the oil gallery are unchanged and of stock size.

It also has the correct stock Model B oil pump with the turned down shaft (.410 As I remember) as discussed in the 1932 Service bulletins page 67.

The pump in my engine does not have the 1/2 shaft that the Service Bulletins says should not be used in a Model B pump or "engine damage will result".

The "early 28" used the undercut shaft. Only use that shaft in that early pump.




Ford went back to the undercut shaft for the "B" engine. You can use the undercut shaft for any pump.



As the 1/2 " shaft is the only one made at this time, Have it turned down if you need the undercut version.



All this information is in the Service bulletin's 28 to 31 and 32 for the "B" pump.

The "Service bulletin's" make it very clear,,,, don't mix up the shafts or you will have insignificant flow !!! and as the Factory put it,,, you could damage the engine!


Copy of SB and dimensions of shaft are on Vince Falter's website:

http://www.fordgarage.com/pages/boilpumpshaft.htm

Please note that there is additional info in the SBs that is not included on Vince's website or as posted above.

Such as which sized shaft can be used in which oil pump housing (there are several housing types) and why that is true.

Cajun 05-20-2013 05:36 PM

Re: High oil pressure
 

I see that you are using a Lion head. Do you have the standard crank pulley? Or have you moved to the smaller diameter Riley billet pulley?

usered 05-20-2013 07:54 PM

Re: High oil pressure
 

Using the standard crank pulley with an alternator.

Cajun 05-20-2013 09:07 PM

Re: High oil pressure
 

Are you able to run with 50% antifreeze?

I have a similar set up with the smaller pulley. My speedster overheats with 50% antifreeze. Radiator etc is clean.

Evidently the head casting has too much space around the impeller. It has been suggested that the stock pulley would solve my issues.

Thanks for sharing your information.

usered 05-20-2013 09:28 PM

Re: High oil pressure
 

I'm running 50% antifreeze with a five blade plastic fan and overflow tank. I haven't run the car to much as I'm just finishing it but to date overheating hasn't been a problem. I've got about 50 miles on it, some of it was at 65 - 70mph. I have another motor I'm running the cast iron Lion and do have some overheating issues. If you want more info PM me and we can maybe hook upon the phone.


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