Oil system myths

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yellow rose

yellow rose

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I just sat through a webinar that featured Tim Foster from Melling (another name drop...never met the man or talked to him but some think that’s a name drop) and the lecture covered many areas of oil pump and oil system requirements.

Three things stood out to me that were myths he debunked.

The first one was a high volume oil pump “sucking” the pan dry. As most of us understand, the system has a volume of leaks built into it from bearing clearances and clearance between the lifters and the lifter bore.

Once those clearances are set, the volume of oil the engine uses does not change, no matter how much oil you try to force through the leaks.

A high volume pump can not “suck” the pan dry.

The second was about lubrication for the timing chain. He pointed out several OEM’s are now specifying pumps that have a built in spray hole to put direct pressure oil on the timing set. He mentioned the OE’s doing it and I don’t recall exactly which engines they were but IIRC one was the late model Hemi.

The third thing he said that I found interesting was his discussion about oil pump mounting surfaces. Tim Foster said the surface of the main cap where the oil pump mounts and the surface of the oil pump should be as flat as possible to maintain any kind of seal.

When asked the question about using a gasket between the cap and the pump if one was available his unequivocal answer was YES. Since a SBM has a gasket available, and according to Tim Foster of Melling that gasket SHOULD be used.


The upshot of all this is get the correct pan to pickup clearance according tone pan you are using, get some pressurized oil to the timing set, and use the gasket between the pump and the cap.

I think by Friday the webinar will be posted online, but I’m not sure if you didn’t listen to it today that you will have access to it.
 
My thing about the gasket is why in the world did Chrysler never use one? I don't think it's price, but something else Chrysler thought didn't warrant the usage of the gasket. I agree about the HV pump though, and it's interesting about the pressurized oil to the chain. Doesn't the factory just use a slinger bolted to the cam gear?
 
Have they ever machined those mating surfaces to accept an o- ring rather than a gasket?
 
Stock (maybe not all?) smallblocks came with a hole in one bolt holding them the cam retaining plate and thereby oiling the timingset long before gen 3 hemis where even thougth about.
 
1Fast340 said:
Stock (maybe not all?) smallblocks came with a hole in one bolt holding them the cam retaining plate and thereby oiling the timingset long before gen 3 hemis where even thougth about.
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But that's not pressurized oil. That's just leaking out of the intake valley.
 
I have to imagine that with a stock pan your timing chain gets oiled every time you decelerate .
 
RammerJammer75 said:
My thing about the gasket is why in the world did Chrysler never use one? I don't think it's price, but something else Chrysler thought didn't warrant the usage of the gasket. I agree about the HV pump though, and it's interesting about the pressurized oil to the chain. Doesn't the factory just use a slinger bolted to the cam gear?
Click to expand...
They probably thought they had Swiss machinist
 
The slinger is constantly whipping up oil to the upper regions of the timing case, and you could drill a small jet in the plugs that go into the lifter bores and continue it through the plate.
jet.jpg
 
Maybe on a race engine it would be a different story, but, has anyone had a good quality double roller chain assembly fail because of lack of lubrication? I've pulled engines apart with 300k on them with the stock chain. Yeah, it was real loose, but, still functional, not blue from heat, and not about to fail. The setup with the silent cam gear (the ones with plastic coated teeth) will fail for sure, but, mainly from the plastic cracking due to age.
 
cudamark said:
Maybe on a race engine it would be a different story, but, has anyone had a good quality double roller chain assembly fail because of lack of lubrication? I've pulled engines apart with 300k on them with the stock chain. Yeah, it was real loose, but, still functional, not blue from heat, and not about to fail. The setup with the silent cam gear (the ones with plastic coated teeth) will fail for sure, but, mainly from the plastic cracking due to age.
Click to expand...

I was thinking about how many really loose chains I've removed through the years on stock engines. Makes me wonder if having pressurized oil to the chain would make a difference.
 
cudamark said:
Maybe on a race engine it would be a different story, but, has anyone had a good quality double roller chain assembly fail because of lack of lubrication? I've pulled engines apart with 300k on them with the stock chain. Yeah, it was real loose, but, still functional, not blue from heat, and not about to fail. The setup with the silent cam gear (the ones with plastic coated teeth) will fail for sure, but, mainly from the plastic cracking due to age.
Click to expand...
Harley had the same problem with their early twin cam chain tensioners coming apart and the gerotor oil pump sending plastic and/or pieces of fine metal throughout the motor until crunch time. Anywhere between 1,000-20,000 miles. Because of supplier change ups the plastic was blamed or the poor finish on the chains edges.
 
RammerJammer75 said:
My thing about the gasket is why in the world did Chrysler never use one? I don't think it's price, but something else Chrysler thought didn't warrant the usage of the gasket. I agree about the HV pump though, and it's interesting about the pressurized oil to the chain. Doesn't the factory just use a slinger bolted to the cam gear?
Click to expand...


Chrysler DID use them. I can’t think of a single small block I took apart that I knew was virgin that did not have that gasket.

So Chrysler did use it. Did it make it into every engine? I don’t know.

But the guy from Melling said to use it.

I will post a link on Friday (or sooner if it hits sooner) so anyone who wants can listen for themselves.
 
yellow rose said:
Chrysler DID use them. I can’t think of a single small block I took apart that I knew was virgin that did not have that gasket.

So Chrysler did use it. Did it make it into every engine? I don’t know.

But the guy from Melling said to use it.

I will post a link on Friday (or sooner if it hits sooner) so anyone who wants can listen for themselves.
Click to expand...
Interesting. I've never seen a small block with a gasket, neither did my Dad. I've pulled apart a few that were for sure virgin and they never had it. Must have been one of those things that either got installed or didn't.
 
I modded my engine to pizz oil all over the place, and depend on the HV pump to still be able to keep up everywhere else. So far so good at over 100,000 miles.
People laugh at me when we talk about it but people also laugh at my flat Earth theory, so pizzonem.

I had a boss once that built a 340 for a customer, and the oil pressure went off the gauge. he spent hours working that pump over, to no good effect. He didn't want to hear anything I had to say. After about the third time the pan came off, he installed a stock pump, and the pressure was still thru the roof. I shut the heck up, cuz he was the boss, and like said, he was sure I would never know the answer.
So the days turned into weeks, and the customer's E-body languished in the corner.
I quit that job over other issues, and when I left, it was still gathering dust.
I had nothing to do with the designing or the assembly of that engine, so I wonder if, or how, he ever solved the problem.
 
In the early 80's I had a 71 RR that I built a 67, 915 headed 440 for. I used a high pressure pump on it and with 6 quarts of oil the gauge would fluctuate. With 7 quarts it was rock solid 72 lbs pressure at cruise, cold it would peg the 100lb gauge. When I rebuilt it I used a HV pump and the pressure was normal with 6 quarts. :realcrazy:
 
yellow rose said:
The second was about lubrication for the timing chain. He pointed out several OEM’s are now specifying pumps that have a built in spray hole to put direct pressure oil on the timing set. He mentioned the OE’s doing it and I don’t recall exactly which engines they were but IIRC one was the late model Hemi.
Click to expand...

I don't know about the V-8 mopars (can't remember)but the slant six did have pressure oiling to the timing chain from the factory.The factory number 1 main bearing had a 45 degree champher on the parting line of the upper bearing shell. Oil sprayed out this channel directly on the chain/slinger. I have never seen a after market replacement bearing with the champher. I always put the champher on that bearing if not using OEM bearings. This can be proven by the fact, that the oem bearings had a different part number for #1 then for #2 and #4. The after market bearings have the same part number for all three locations.

Edit: Just did some checking and the big blocks had the same "oiling" champher on the #1 upper main bearing shell. I did not find any referance of this on the small blocks.
 
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my experience:
  • Every factory stock small block mopar I've taken apart did not have a gasket for the oil pump.
  • Every factory stock small block mopar I've taken apart did not have a hole in the bolt for the cam retaining plate.
 
318willrun said:
my experience:
  • Every factory stock small block mopar I've taken apart did not have a gasket for the oil pump.
  • Every factory stock small block mopar I've taken apart did not have a hole in the bolt for the cam retaining plate.
Click to expand...


That’s weird. Well not the second part but certainly the first part.
 
By the way, if I use the oil pump gasket, I ALWAYS use Indian head shellac on both sides of the gasket.
 
I've torn down so many engines, there's no way in hell I'd ever commit to know "ALL" of them were one way or another. No way in hell.
 
Same here, but, it seemed to me that for the most part, the engines up to.'68 or so had the holed bolt, and the ones after that came with the 3 bolt plate and the oil slide.
 
Maybe it was factory specific ?
1 plant used gasket .. 1 did not ...?
 
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