I don't have a copy of service bulletins and was wondering if anybody knows why they changed the valve cover in May of 29 to lower the return pipe? Did they change the block also or is the oil passage for the rear main bearing unchanged. Seems like the main bearing would be less likely to starve of oil with it being a little higher, especially going down hill.
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They lowered it to help prevent oil burning, I believe everything else is unchanged3~ Tudor's & 1~ Coupe
Henry Ford said,
"It's all nuts and bolts"
"Start by doing what's necessary; then do what's possible; and suddenly you are doing the impossible."
Mitch's Auto Service ctr -
It was changed to lower the oil level in the valve chamber to keep the oil off the valve stems, to slow down oil consumption. The outlet for the oil return pipe was positioned lower, and the pipe lengthened to match. It is necessary to use the oil return pipe that matches the cover, in either case.Comment
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Ok, consider this scenario. Let's say you have the early valve cover with a higher level drain pipe. Your engine is warm normal operating temp you have been driving and get to your destination, turn off the engine. After the engine is off you have oil from the engine draining back to the pan and the oil level is raising maybe faster than the oil draining from your rear main bearing which is also still getting oil from a higher oil level side cover even tho the valve chamber is no longer getting oil, there is more oil in that chamber to drain down before it's level where it won't drain any longer. Could this have an effect on the rear main leaking after the engine is shut off while when the engine is running at any rpm it does not leak? I ran this engine for 3 hours at several different rpm and not a drop of oil leaked out the cotter pin hole. As soon as it was turned off 30 seconds later it starts to make a puddle 4" in diameter leaking from the flywheel housing cover plate and cotter pin hole. So all you engine experts give me your opinion. I have my theory on what the real problem is and it's not just this, but I want to cover all bases before I pull this engine again. And btw I have a different cover and pipe ordered on it's way.Comment
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Dennis, your theory makes sense to me. While running, the oil is slung up and around the oil slinger and is drained back into the pan. After the engine is shut down, it doesn't have that rotational movement and the flood of oil into the rear bearing area can't drain back as fast as it gathers so it over flows the slinger galley and drains back into the flywheel housing.
I would ask a couple questions...is it babbit or insert bearings? What is the gap in the rear main bearing? Have you had the pan off and checked to be sure you have the drain tube on the rear main? How close to the Full mark on the dipstick do you keep the oil level?
I am thinking that all these can be a contributing factor. The worst of these the gap in the bearing too loose and allowing the oil to drain from the valve chamber to the rear main instead of back into the pan.
That's my opinion, and I'm stickin to it!You wana look waaay far up da road and plan yer route because the brakes are far more of a suggestion than a command!Comment
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Everything is as it should be. Inserts. Oil level at the bottom of F mark. Also was told the block casting where the oil hole for the rear main bearing is higher on a early 29 block than later blocks. So I'm not changing the valve cover to lower the drain. I was told it will not change how the rear main leaks or not.Comment
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Does your rear main bearing cap have a 5/16 or 3/8 inch drain pipe? That would be a factor.Comment
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3/8 drain pipe.Comment
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My inserted engine with the later valve cover leaked, driped after shutting off when the oil level was near the full mark on the stick. It's now half way between full and add, seams to not leak,drip after shutting off. Your results may very!Comment
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From post #4. "And btw I have a different cover and pipe ordered on it's way."
From post #6. "So I'm not changing the valve cover to lower the drain." I should have said cover AND pipe. What my main concern was, Is the block in the area higher on a pre May 29, than a later 29 to end of 31 and I was told it is, so because of that I'm not changing the pipe and cover.
I already know this, but I don't know what is in the rear main cap or what if anything has been done internally to the rear main cap. If memory serves me correct, there is something like a plug or cover that is on the front side of the cap from when these caps are made to drill the drain hole from the rear of the cap where the aluminum ring is forward to the drain pipe. When I took the caps and crank out in the past I noticed there was a small glob of babbitt in that galley groove that I felt would restrict the oil drain from what it should have been. It wasn't blocking the drilled hole but was next to it. I should have taken a picture of that and might have and will go back through 5,000 pictures and look for it. I personally didn't remove the plug to check for a restriction or machine for inserts or clean that babbitt from the groove or assemble the crank in the block and install the main bearing cap. Brent you mention a "journal pin with clearance of the insert shell being excessive". Is this pin in the block or the main bearing cap? Like I said I have never had this crank out to inspect the crankshaft or bearings yet. So Brent, thank you for the information on the pin and the bearing shell. I assumed these blocks when machined for inserts had the common groves cut for the tabs on the bearing shells which from my experience is most common. I've never seen pinned bearing shells.
The engine has not been pulled yet and it pretty much looks like what is wrong is in the area of the rear main bearing. So thank you all for your input.
One other thing I've read is the access cover on top of the bell housing was changed from non vented to the one that has the louvers because the non vented could cause a vacuum. Whether this is true or not the cover was changed prior to when the inserted engine was installed. The fill pipe has no restriction nor does the breather cap have any wadding or such, tabs are correct in the cap to provide clearance so the crankcase can breath. I have done the bag test on the breather to check for blowby and that passed the test, no blowby.
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Never heard about that vacuum myth... it was changed for ventilation issues
Post #190
remember there is a cam gasket back there -
No gasket, was told to assemble with RTV, I always use Permatex Ultra Black and have never had a problem. What I like about Bill Stipe cams is that he drills a hole parallel to the camshaft in the last bearing journal I assume to relief pressure should there be any at the rear of the camshaft. Also no cracks in the flywheel housing and it is dialed in to within .002" runout all the way around top bottom sides. All the bolts that go through to inside of block have been sealed also. This is not saying one of the bolts or the housing isn't leaking in this area. It might be hard to determine without taking it off and with oil getting sprayed around in there from the flywheel.Last edited by Dennis; 11-30-2017, 01:23 PM. -
I had to hunt for that..png "roll eyes")
and you and I even commented on that. Boy I sure feel like a dumb shit now! I must have read the myth on the dark side... where else could I have seen that... I better start reading all the questions and correct answers and try to remember a little better .png "eek")
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Be sure to check the R front motor mount bolt. It passes all the way thru the timing cover. It needs sealant. Don't care how tight it is. An old timer put me onto this long ago. I have seen cars with what you would SWEAR have a rear main leak, only to discover that oil has found a nice hidden path from that bolt to the edge of the pan, worked its way back, and routed itself to appear like a rear leak, and it will puddle up as well as any rear leak when the engine is off
We have corrected several 'rear main leaks' with this simple fixComment
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Oops ! I know someone that didn't seal that bolt, Thanks for the tip !Comment
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I have been seeing folk getting all over MMO and questioning the reason for using it. Well, I think it is time to clear a bit of air within these airheads and explain why MMO or Seafoam, or these top end lubricants are almost a must.
If you will take a look at this picture of the valve chamber, you will see to the right a copper tube protruding from the bottom of the valve valley. Well,...09-05-2017, 10:30 PM -
I’ve had my rear main bearing cap off for over a week and was expecting the oil in the back of the valve chamber to slowly ooze down the oil gallery and past the crankshaft and drip out. There’s still a bunch of oil in the valve chamber and I don’t see oil coming out around the crank. Would this mean the oil gallery is stopped up, or is it even supposed to work that way?.gif "confused")
11-02-2021, 12:19 AM -
Question, has anyone had success in soldering the oil return pipe back onto the ends? Mine fell apart when I took the bolts out of valve cover! I’ve read that some say yes others say no. Is it done on or off the engine? What did you use for solder? Lead based or brazing rod? Do they sell a fully assembled new one? I know they changed the bend for better flow can’t remember what years fit what?11-12-2020, 09:52 PM -
Many of you have been following my other timing gear thread, but wanted to start a new one for future searchers. I have checked my car before for oil flow, by loosening the side return pipe and having oil poor out of it. I just started by car for the first time since the most recent timing gear swap. I let it idle for about a min and then started to loosen the oil return pipe and no oil came out....08-18-2021, 07:28 PM -
Al, we really need a fresh thread to get this going, so here it is. I am very interested in the way you did that, and it looks so simple.01-26-2018, 09:42 PM
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Out of curiosity, where do the valves pick up their lubrication? I have my valve cover off currently, and noticed the hole to the timing gear is lower than the crown of the valve guide, so it must pick it up from underneath somewhere...07-27-2021, 07:41 PM
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I changed my oil today but did not pour any oil down the distributor hole as many claim they do. I have read, looked at pictures and diagrams but fail to understand the logic behind it. To me the oil would go around and down the shaft, over the pump and into the sump. Oil poured into the crankcase tube goes to the same place. If changing oil removes oil from the upper valve chamber so would letting...03-30-2021, 05:43 PM -
I got my 31 coupe started for the first time in 10 to 15 years two weeks ago. with the exception of a stuck exhaust valve everything seemed pretty good.
I pulled the head and valve chamber cover to address the valve issue. under the head looked pretty good, but the valve chamber had a lot of thick gunky oil still in it. While I am working would it be worth my while to pull the oil pan and clean...07-12-2020, 12:35 PM -
Has anyone been using the EZ oil drain valve for draining the crankcase oil?
If so, do you recall which size you use? The chart does not list Model A Fords.png "smile")
https://ezoildrainvalve.com/index.html01-21-2023, 04:10 PM -
I have a 1931 Model A with an original engine, never out of the frame or rebuilt. What type and weight oil would be the best for this Car ?11-28-2018, 10:30 AM
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