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Old 04-14-2018, 08:30 PM   #1
Fred n' Ethel
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Question Oil pressure

Hi folks.
In your experience, what does the following info indicate regarding the condition of my stock 1954, 235.
Outside temp 85f, 20 mile warm up city and highway.
Coolant temp never up to the midpoint.

Following oil pressures are est. from the stock 0-60 gauge.
At idle - 5 ish psi.
In 3rd gear, 25 to 30 in town - 10 to 14 psi.
Highway speed (50 to 55) 30 to maybe 32 psi.
Using straight 30W oil (100 mi. old)

Changing the oil soon, what would you recommend ?

Thanks
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Old 04-14-2018, 08:43 PM   #2
Black_Sheep
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Re: Oil pressure

Quote:
Originally Posted by Fred n' Ethel View Post
Hi folks.
In your experience, what does the following info indicate regarding the condition of my stock 1954, 235.
Outside temp 85f, 20 mile warm up city and highway.
Coolant temp never up to the midpoint.

Following oil pressures are est. from the stock 0-60 gauge.
At idle - 5 ish psi.
In 3rd gear, 25 to 30 in town - 10 to 14 psi.
Highway speed (50 to 55) 30 to maybe 32 psi.
Using straight 30W oil (100 mi. old)

Changing the oil soon, what would you recommend ?

Thanks
Sounds low, the general rule of thumb is 30 psi @ idle and 10 more pounds per 1000 rpm. The first thing I would do before getting too carried away is check it with a different gauge to verify that your gauge isn't out of whack...
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Old 04-14-2018, 10:01 PM   #3
Fred n' Ethel
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Re: Oil pressure

I have a new gauge on the shelf, will try that tomorrow, thanks !

Found this while searching around .....
The full pressure 235 engines when new will have up to 50 PSI off idle and 20 ~ 35 PSI @ idle but that will usually drop by 10,000 miles .
Again , as long as the oil gauge needle comes up off the peg when you give it throttle , it's good to go , don't worry about it .
I was going down the freeway to-day at a good 65 MPH , engine singing it's song and oil pressure at maybe 30 PSI ~ it doesn't run hot and no discernable bearing knocks at any speeds or loads .



What is the modern equivalent of a "good" SUMMERTIME oil/weight to run nowadays ?
Thanks !
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Old 04-14-2018, 10:05 PM   #4
Speedbumpauto
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Re: Oil pressure

Those things never had any real pressure to start with. You didn't say whether the cold pressure was higher than the hot pressure. If the cold pressure is somewhat higher than the hot, I'd change to a dino multi vis in the 20-50 or 20-40 range. That old 235 will live forever on 20-30 psi, IMO.
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Old 04-14-2018, 10:50 PM   #5
Fred n' Ethel
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Re: Oil pressure

I'll take note of the cold pressures when I fire it up next time.
Will try the heavier multi-vis oil too.

I do understand the difference.
Just looks like this 54-235 is more resembling my 39-216
The 216 reallyworried me at first, till I learned it was better than average idling at 5 and rippin down the highway at 15.

Thank you.
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Old 04-14-2018, 10:52 PM   #6
Foot Stomper
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Re: Oil pressure

Here's a short video (and picture) of my brand new rebuilt 235 running at idle. Running 40 PSI.
The motor hasn't run more than 20 minutes at the time of this video.

https://photos.app.goo.gl/GhbcuqTLEzsXeD0i1

The kind of oil is entirely up to you as there as many opinions on that topic as pebbles on the beach. Just use a good one, with a good filter and change it often.

I've read often times also that 5 psi at idle is quite normal and nothing to be concerned about.

Your water temp should be close to 195 to get proper power. They like to run hot.
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Old 04-15-2018, 04:04 PM   #7
dsraven
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Re: Oil pressure

remember the guages are not even close to new, so they could be off some. best would be to run a "T" in the line and install a new guage right there. check the new against the old and see how it compares.
if it turns out that the engine heat is low, try a new OEM thermostat. I say OEM because I have installed many thermostats of the cheaper variety and they have been no good right out of the chute. replaced with OEM and the heat worked like it should.
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