Oil flow. Oil doesn't flow through heads?

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The camshaft is pressurized on OHC motors. I think Toyota uses the front cam bearing and the cam has holes in it to transmit the oil to the other journals. What I don't understand is how on the bucket lifter in the head type motors oil gets to the valve stems and valve tips. It must work it's way through the lifter bore I guess.
 
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Here is a classic video that was made to show the effect of cold weather on oil but it happens to show the flow of oil in an overhead cam engine. Yes, oil flows up into the head and drains back to the oil pan. Look at the video at 5:39. Enjoy.

At 6:15,is he using conventional? It looks full of wax compared to the first startup flow segment, which the oil looks clear, I'm assuming was synthetic.
 
At 6:15,is he using conventional? It looks full of wax compared to the first startup flow segment, which the oil looks clear, I'm assuming was synthetic.
It’s a pretty old video and was done at a time when Esso was trying to introduce synthetic oil to the market place, so yes, they were probably trying to get consumers worried about cold weather starts with conventional oil and also were probably not comparing grades directly as well.
 

JT20

Thread starter
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I’m a hands on learner lol I can’t do anything with words or pictures hardly
I maybe used to be that way, now I can more look at anything and be.. "This must be this, so".. etc.

I have to watch the videos when I get in.. I put 0W-20 in the Taurus and went for a drive. Now I'm eating
(and replying to BITOG with what needs to be replied to lol.)

We're all good.
 
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The camshaft is pressurized on OHC motors. I think Toyota uses the front cam bearing and the cam has holes in it to transmit the oil to the other journals. What I don't understand is how on the bucket lifter in the head type motors oil gets to the valve stems and valve tips. It must work it's way through the lifter bore I guess.
Oil enters through a hole in the side of the lifter in the lifter bore. In the lifter cup is a small hole and check valve. Push rods are hollow. When the cam pushes the lifter up to open the valve, the push rod compresses the parts inside the lifter and the oil trapped in the lifter is pumped through the push rod up into the head lubricating the rocker,valve and springs. If you have ever had the valve cover off a running engine you would be amazed how much oil is moved through the push rod.
 
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Last night, we were discussing a different topic and I got shade thrown pretty well over me suggesting "Oil flows through a head." In typical BITOG previous fashion, this was dwelled on. I was able to diffuse the situation, but now, I would like to review how oil flows through various heads.

Many different engines out there. When I see a block, I see Oil Return Passages. So this must mean that the oil comes back down.. Has to, otherwise it would stay up there forever. So, it doesn't travel up the whole head or side of through maybe some kind of pressurized channel, it just gets splashed up there from the upward movement of the piston?

Then I suggested the Oil Return Holes that are directly in.. I said the piston, maybe PimTac took offense to that. Perhaps I should have stated the Connecting Rod underneath the piston. The piston is that moves up and down and has the oil control rings in it, I think there are three ? But I distinctly remember it being said that there is a long shaft that goes up/down through the apparatus under it, that helps oil flow.. So, perhaps that is the connecting rod, and not necessarily the piston (although it all moves up and down as one unit. Thank you, PimTac.)

Can't get enough lubricating, so. Are the holes I speak of in the part under the piston? And are there ANY engines that get pressurized and not splashed oil in the head?

Perhaps from 13:19 on in this video. Would make sense... Oil would drain back down through the center of the big long connecting rod under the piston and provide oil lubrication to that bearing at the bottom.
Typical pushrod engine-oil flows from lifters up the pushrods and onto the valve train. Oil then drains back via designated drain holes. Overhead cam engine-oil flows through cam bearing journals and onto valve train. Likewise for drain back holes.
 
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