Interesting video about Cleveland heads oil drain back

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According to this guy, the Cleveland heads will hold about 3qts. of oil during high RPM operation (that's for both heads). So if you have a factory pan that holds 5qts that only leaves 2qts. There will maybe about 1 quart within the filter and system which would leave very little at the bottom of the pan for the oil pan to pick up. Makes perfect sense but I have never seen anyone measuring the amount of oil on the heads.

The video goes slooow and he goes through a whole section talking about the Holden 302. You can watch the first couple minutes and then jump to minute 11 and still watch by fast forwarding. The bottom line is that there is a lot of oil up there. No wonder why those valve covers are always leaking.
 
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Yeah, this video has me wondering if I should use old 4V heads at all and maybe just get some new heads. The 3V seem to be the best option for a rebuild if you're gonna start from scratch.

I guess the only cure is a massive oil pan that will allow for an extra 3 litres of oil so you don't run dry or go with a dry sump.
 
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The lower drainback holes go through the block. By the time the upper areas (push rod holes, etc) come into play, the valve covers will be holding a lot of oil....doesn't matter which heads.
 
The lower drainback holes go through the block. By the time the upper areas (push rod holes, etc) come into play, the valve covers will be holding a lot of oil....doesn't matter which heads.
I agree. The drain holes will drain about the same in the stock compared to the modern heads. The difference will be on the drain holes to the valley. Some of the modern heads have large cavities here instead of the pushrod holes of the stock heads.
 
... humm, he seems to forget that HOT oil is more fluid... G-Forces will move push that hot oil out the rear drain holes, and as oil rises in the rear, it is pushed out the push rod holes.

If it's a general issue, then Ford had the same with many other heads besides the 351 4V
https://7173mustangs.com/threads/unusual-request.41536/post-444212

Racers for decades, and decades, and decades where rules allow run dry sump engines.. Oil sprayers in valve covers tooooo.

Remember free advice is free until you use it and fine out how wrong it is...

edited: Was is very common in the day, to just/always run a .040 restricter push rod of the style PR you like.
Screenshot 2024-02-26 at 4.46.39 PM.png
 
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... humm, he seems to forget that HOT oil is more fluid... G-Forces will move push that hot oil out the rear drain holes, and as oil rises in the rear, it is pushed out the push rod holes.

If it's a general issue, then Ford had the same with many other heads besides the 351 4V
https://7173mustangs.com/threads/unusual-request.41536/post-444212

Racers for decades, and decades, and decades where rules allow run dry sump engines.. Oil sprayers in valve covers tooooo.

Remember free advice is free until you use it and fine out how wrong it is...

edited: Was is very common in the day, to just/always run a .040 restricter push rod of the style PR you like.
View attachment 86095
Good point about hot fluid. BTW, I did not take this as an advice. I just thought it was an interesting video so I posted here for critique and opinions.
 
I know practically nothing about engines other than the basics, but I noticed a couple of things......... apart from this guy tells a story just like my wife, goes on and on and ......
I am curious even more, why Ford removed the rear drain holes in the earlier "J" block and added a crude hole at the front in the "L" block. As the engine sits with the rear lower, was it an attempt to keep oil up into the heads and front of the engine? Did the "J" block drain too quickly thus keeping the valves and cam starved for oil? I don't know, but something I've wondered about. Years ago now, I sold a J block because I was under the impression that it was a bad block, oil wise. I could have kept it and modified it.
Also, and correct me if I'm wrong, isn't the Boss oil pan the same as a standard 351C, other than a windage tray added, but spec'd for 6 US quarts of oil? If that's the case, we ought to be able to run 6 quarts in any 351C, giving that extra quart. Or is it the windage tray what makes the difference to control the oil in the sump.
One thing I do know from my own engine screw up, don't run a high volume oil pump.
 
I know practically nothing about engines other than the basics, but I noticed a couple of things......... apart from this guy tells a story just like my wife, goes on and on and ......
I am curious even more, why Ford removed the rear drain holes in the earlier "J" block and added a crude hole at the front in the "L" block. As the engine sits with the rear lower, was it an attempt to keep oil up into the heads and front of the engine? Did the "J" block drain too quickly thus keeping the valves and cam starved for oil? I don't know, but something I've wondered about. Years ago now, I sold a J block because I was under the impression that it was a bad block, oil wise. I could have kept it and modified it.
Also, and correct me if I'm wrong, isn't the Boss oil pan the same as a standard 351C, other than a windage tray added, but spec'd for 6 US quarts of oil? If that's the case, we ought to be able to run 6 quarts in any 351C, giving that extra quart. Or is it the windage tray what makes the difference to control the oil in the sump.
One thing I do know from my own engine screw up, don't run a high volume oil pump.
Actually, the Boss oil pan also is used in the M code, at least the earlier M codes as mine. However, my oil dipstick was the non-boss. From what I have read they just changed the location of the oil level for one more quarter. The windage tray should keep more oil in the sump than rotating with the crank but that shouldn't limit anyone from adding one more quart to their pan. When the engine is on there would be just a few quarts in the pan so there shouldn't be any risk of the crank diving into the oil besides the oil cloud.
 
Actually, the Boss oil pan also is used in the M code, at least the earlier M codes as mine. However, my oil dipstick was the non-boss. From what I have read they just changed the location of the oil level for one more quarter. The windage tray should keep more oil in the sump than rotating with the crank but that shouldn't limit anyone from adding one more quart to their pan. When the engine is on there would be just a few quarts in the pan so there shouldn't be any risk of the crank diving into the oil besides the oil cloud.
That's much as I thought. It might be a good idea especially with a 4 speed as they do use more oil due to the engine braking effect. I'm always down at least a pint in about 1500 miles or so with no leaks or burning.
A new original sump with the tray would be nice to have though.
 
Actually, the Boss oil pan also is used in the M code, at least the earlier M codes as mine. However, my oil dipstick was the non-boss. From what I have read they just changed the location of the oil level for one more quarter. The windage tray should keep more oil in the sump than rotating with the crank but that shouldn't limit anyone from adding one more quart to their pan. When the engine is on there would be just a few quarts in the pan so there shouldn't be any risk of the crank diving into the oil besides the oil cloud.
Yes, that is correct. Here are the part numbers from the MPC. The 4 barrel 351Cs used the same pan, the Boss (351 Spec) used a different length dipstick
Oil pan-dipstick.jpg
 
Yes, that is correct. Here are the part numbers from the MPC. The 4 barrel 351Cs used the same pan, the Boss (351 Spec) used a different length dipstick
View attachment 86158
I'm curios Don, was the Cleveland 2V pan different and why? Was the dipstick the same as the 4V? That to me doesn't make sense.
My 4V oil pan has no baffle in it and I believe it to be the original. Maybe I'm just getting this all wrong. (wouldn't be the first time!!)
 
The picture is the original pan from my 72 H code with 5 quarts of water (simulating the 6 quart total capacity used in a Boss pan). The lower pic is a Boss/Q code pan.

I wonder if one of our pans is the result of Ford's "keep the line moving" philosophy and a substitute was made.

1709218695042.png
1709218837425.png
 
The picture is the original pan from my 72 H code with 5 quarts of water (simulating the 6 quart total capacity used in a Boss pan). The lower pic is a Boss/Q code pan.

I wonder if one of our pans is the result of Ford's "keep the line moving" philosophy and a substitute was made.

View attachment 86169
View attachment 86170
That could be, an 'on the fly' change.
The reason I know my pan does not have any sort of baffle goes back to before the engine was rebuilt the first time in 2012. Previously, a grease monkey at the lube shop, stripped the plug threads. Their shop's mechanic rethreaded it for a larger plug.
When the engine was apart, I made it a point to have the builder check that thread. It's a small block spot welded on the inside and was ok. That is when I got to see the inside of the pan.
I've often thought about finding another pan to replace it with, but as it's a total pita, I'm in no rush.
 
According to this guy, the Cleveland heads will hold about 3qts. of oil during high RPM operation (that's for both heads). So if you have a factory pan that holds 5qts that only leaves 2qts. There will maybe about 1 quart within the filter and system which would leave very little at the bottom of the pan for the oil pan to pick up. Makes perfect sense but I have never seen anyone measuring the amount of oil on the heads.

The video goes slooow and he goes through a whole section talking about the Holden 302. You can watch the first couple minutes and then jump to minute 11 and still watch by fast forwarding. The bottom line is that there is a lot of oil up there. No wonder why those valve covers are always leaking.

It’s funny I ran my car just for a couple minutes with the hood open the other day and after shouting it off I went around to the battery side and I could hear fluid draining back to something and figured it was the oil in the heads draining back to the back. 🤷🏻‍♂️
Oh I do have a deep 7 quart pan.
 
The picture is the original pan from my 72 H code with 5 quarts of water (simulating the 6 quart total capacity used in a Boss pan). The lower pic is a Boss/Q code pan.

I wonder if one of our pans is the result of Ford's "keep the line moving" philosophy and a substitute was made.

View attachment 86169
View attachment 86170
Thanks for these pictures, they confirm what I thought, the 2V and 4V pans are the same size, with the 4V getting the scraper. This also explains why both pans use the same dipstick.
 

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