Bearing fit ... engine oil gravity feed

[warrene]

Just finished my engine overhaul, new modern rings, valve job, new stainless steel valves, adjustable lifters. I fitted the mains and rods at .001 or less, I use 5W-20 oil same as your newer cars.
Thicker oil at low temp' can feed very slow or almost not at all down those 3 tubes to the mains, with thinner oil there's feed right away even in sub zero temps. Same goes for tranny and rear ends with this old 600 tar, until the grinding friction heats it up you have no lube on gears at all, this is what ruined tons of old cars years ago, cold weather the thick oils is a death sentence. Run 80-90 or universal tractor fluid, both are high EP lubes. Use the modern stuff, do your car a favor.

warrene

[Jim Brierley]

I agree, but like more clearance, .0015 minimum.

[kenparker]

i am with Jim on thsi one .0015 claearance.

[Chuck Sea/Tac]

What’s your piston clearance?

[Kurt in NJ]

The original bearings hold a lot of oil--- even years later there is enough in them to drip when taking apart ---

[Kohnke Rebabbitting]

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I agree with nothing, in post No. 1.

Herm.

[CWPASADENA]

I also agree with .0015 clearance in the bearings.


I am in Southern California and run 20/50 oil. 5/20 is way too thin when driving across the desert on a hot day.


My opinion,


Chris W.

[28Danby]

Doesn't 600W in the transmission aid in shifting as it slows the gears enough to shift. Too thin of oil and your grinding gears. Correct me if I'm wrong though

[Patrick L.]

Originally Posted by 28Danby

Doesn't 600W in the transmission aid in shifting as it slows the gears enough to shift. Too thin of oil and your grinding gears. Correct me if I'm wrong though

Thats correct. However some think that 600W is the weight of the oil. It isn't, its a designation. 600W is about 140-180 weight.

[Bob Bidonde]

Bearing clearance should allow crankshaft to turn at about 75 lbs-ft of torque. I do not understand the logic of using 20W50 oil becuase at 50 viscosity, the oil flow is less than a SAE 30.

[Patrick L.]

Originally Posted by Bob Bidonde

Bearing clearance should allow crankshaft to turn at about 75 lbs-ft of torque. I do not understand the logic of using 20W50 oil becuase at 50 viscosity, the oil flow is less than a SAE 30.

Bearing clearance should allow the crank to turn very easy. Ring tension is a different animal.

20W50 designation is a 20 weight oil with the film strength of 50.

[ryanheacox]

I'm not an engine builder but I am a mechanical engineer so if Herm or anyone else with experience corrects me I will yield but 75ft-lb just to turn the crank seems like way too much. Maybe on a fully assembled fresh engine in the car with new rings but even then it seems like too much.


When I went down to check the progress on my engine, the rebuilder had fit the crank and could spin it by hand with relative ease. Snug would be the word to describe it.

[katy]

I agree, but like more clearance, .0015 minimum.

Warrene's engine will open up to .0015" soon enough.

[Purdy Swoft]

It will probably run pretty warm until it does . I run two thousands clearance on the crankshaft bearings and run 20W50 oil

[Jim Brierley]

I should be more clear on the subject. I personally run .002" clearance for street use, and .0035 piston clearance. .0025" and .008" on my race engine. 20-50 oil but synthetic racing for Bonneville. Modern oils in the gear boxes.

[Synchro909]

Originally Posted by katy

Warrene's engine will open up to .0015" soon enough.

But in the mean time????
I once heard it said that there are plenty of cars running around out there with bearings that are too loose. There are no cars running around out there with bearings too tight.
I run a clearance of 0.002" and use 20W50 oil, like Purdy.

[Kohnke Rebabbitting]

If your running a true .001 or less, on set up, the bearing has no choice but to Smear the first .010 of babbitt, or less, and that is a waste. Normal Rod clearance of a broke in engine is .002, to .003 thousandths, depending how much heat you crate, running at higher speeds.

All our bearings, we set our clearance to, .001 per inch of shaft, and always then plus a half, .000-50. So a shaft of 2.500 would get .003 thousandths clearance. Never had any problems.

We use straight 30Wt. Summer, Straight .20Wt. winter.

5-30's, and the like, do not have enough cushion of oil molecule to keep shaft, and Babbitt separated, very thin oil film.

Herm

[Benson]

EDIT
Herm I did not see your post.

[Benson]

Herm,


1. Is 20W50 oil too thick for a B Engine in Winter?


2. Too thick in Summer?


Sounds like you avoid Multi weight oils?

[Kohnke Rebabbitting]

Originally Posted by Benson

Herm,


1. Is 20W50 oil too thick for a B Engine in Winter? " End Quote "

It would be for me, in winter. I used 20-50 in my 1992 Ford truck, in summer, and 10-30, in Winter. It Broke a piston last fall, at 8,000 short of 400,000, it never had a wrench on it.

Had a 1967 Dodge Maxi van, that I pulled our band trailer with, and the band, of course. Had a valve go bad at 400,013 thousand, so I got a rebuilt engine from Gopher, in Minneapolis and put another 18,000 on that engine, and the crank broke, Diagonal, in the last Rod Pin. We were coming home from out in Nebraska, after playing a Bar, on Friday night, Wedding dance on Sat. night, and a Rodeo on Sunday after noon. Anyway, we drove somewhere around a 150 miles, at 30 miles an hour, and made it home, but it was really starting to pound. Gopher gave us another engine, and I sold it with 175,000 on that engine.

Had a 1974 Ford Maverick Grabber, Special order order paint, Dark Red, and White decals, only new vehicle I ever bought. After 451,000, I sold it to my girl friend, she put on 48,000, an sold it to a guy in Humboldt, Iowa. He drove it to his job at a Limestone Quarry for two years, and the driver door fell off, from rust, and he pulled the motor, and put it in a motorless pickup he had, in his back yard, and drove that to work. I never found out how many miles he put on, but his wife said that it still didn't use any oil. The Ford motors were 302's.



2. Too thick in Summer? No, I wouldn't think so.


Sounds like you avoid Multi weight oils?

" End Quote

Yes, for all the bearings we work with.

Take a little 5-30, or other multi oil, an warm some in a little saucepan, and and when you can touch it without burning yourself, put some between your index finger, and thumb, and rub them back and fourth, hard. Then do the same thing with 30-Wt., and see what you think.

I hope I didn't tell you more then I know!

Herm.