oil for flathead
Senior User
Joined: Sep 2003
Posts: 231
Likes: 0
From: Meta, MO
I was worried about not knowing what the engine had in it previously, and then possibly mixing detergent and non-detergent oils.
My mechanic told me to run 10w40 and check the oil often. Change it as soon as it started getting dark. If the detergent starts knocking some of the old sludge loose, the oil change would take care of it.
For what it is worth, my mechanic has been around long enough that he worked on this stuff when it was new. I hope to change the oil this week and see how it goes from there.
My mechanic told me to run 10w40 and check the oil often. Change it as soon as it started getting dark. If the detergent starts knocking some of the old sludge loose, the oil change would take care of it.
For what it is worth, my mechanic has been around long enough that he worked on this stuff when it was new. I hope to change the oil this week and see how it goes from there.
Fleet Owner
Joined: Jul 2004
Posts: 27,299
Likes: 1,059
From: NM
It can't hurt to watch the oil closely, but non-detergent oil has been downright hard to find for at least 20 years. You can be pretty confident detergent has been used.
Still, if this is not a rebuilt engine, if it's a dragged-in-from-the-field motor, I would pull the pan before even cranking it over. What you find there may save a disaster. Clean the screen on the oil pump pickup, scrape any goo out of the pan. If you have the truck pan with the big hole in the bottom this is really easy to do with the pan in place. Even if you have a car pan with no hole, dropping the entire pan is at most a half-hour job -- and you can paint it up pretty too! You can also wiggle the rods' big ends to see if they are OK, you get a good general idea of what condition the engine is in.
If you've been on here long, you'll know I am not a fan of cranking up engines that have been sitting for years just so you can hear them run. It can do hundreds of dollars of damage compared to checking out the insides first, doing some pre-lubing, etc.
Still, if this is not a rebuilt engine, if it's a dragged-in-from-the-field motor, I would pull the pan before even cranking it over. What you find there may save a disaster. Clean the screen on the oil pump pickup, scrape any goo out of the pan. If you have the truck pan with the big hole in the bottom this is really easy to do with the pan in place. Even if you have a car pan with no hole, dropping the entire pan is at most a half-hour job -- and you can paint it up pretty too! You can also wiggle the rods' big ends to see if they are OK, you get a good general idea of what condition the engine is in.
If you've been on here long, you'll know I am not a fan of cranking up engines that have been sitting for years just so you can hear them run. It can do hundreds of dollars of damage compared to checking out the insides first, doing some pre-lubing, etc.
Junior User
Joined: Jun 2004
Posts: 97
Likes: 0
10/40 weight oil
something to consider:
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http://www.micapeak.com/info/oiled.html
Very few manufacturers recommend 10W-40 any more, and some threaten to void warranties if it is used. It was not included in this article for that reason. 20W-50 is the same 30 point spread, but because it starts with a heavier base it requires less viscosity index improvers (polymers) to do the job. AMSOIL can formulate their 10W-30 and 15W-40 with no viscosity index improvers but uses some in the 10W-40 and 5W-30. Other multigrade synthetics may not use VI improvers either. The full literature available from the oil company should include this information.
from “More Than You Ever Wanted to Know About Motor Oil”<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com
fficeffice" /><o></o>http://www.micapeak.com/info/oiled.html
Very few manufacturers recommend 10W-40 any more, and some threaten to void warranties if it is used. It was not included in this article for that reason. 20W-50 is the same 30 point spread, but because it starts with a heavier base it requires less viscosity index improvers (polymers) to do the job. AMSOIL can formulate their 10W-30 and 15W-40 with no viscosity index improvers but uses some in the 10W-40 and 5W-30. Other multigrade synthetics may not use VI improvers either. The full literature available from the oil company should include this information.
Junior User
Joined: Jun 2004
Posts: 97
Likes: 0
you may also want to review this thread on oil from last week
'59 223 six oil pressure 101
https://www.ford-trucks.com/forums/5...ure-101-a.html
Tony 1955 F350 dually dump
'59 223 six oil pressure 101
https://www.ford-trucks.com/forums/5...ure-101-a.html
Tony 1955 F350 dually dump
Postmaster
Joined: Nov 2006
Posts: 4,517
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From: SE Wyoming
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Senior User
Joined: Aug 2004
Posts: 328
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It's been a year since I changed mine but IIRC it's about 5 1/2 quarts. I run Valvoline straight 30. Be very careful you get the gasket for the oil filter housing in correctly and double check it with the engine running.
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