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If you have hydraulic roller lifters (like a ZZ4, L98, or any modern engine), my understanding is that you do not need extra ZDDP. That's only for flat tappet cams.
I’m going to be gone for 4 days but I’ll cut ‘er open when I get back. And maybe even share some photos — how EXCITING!!
While I don’t doubt you, Jebby, and I know you’ve got a ton of experience, I will challenge you to offer a different explanation. In the end, all I did was an oil and filter change (along with a lot of mini-checks along the way that just confirmed there weren’t any outside issues). I’ve detailed everything I did and tested. If all of that evidence I presented was presented to me, a clogged filter would be my first guess — regardless of whether I’d ever personally seen that or not. And, yes, if it is clogged with metal shavings, then the smile on my face will quickly fade.
Ok....simple.....the pleated filter area would have to be almost 100% plugged to cause the oil pressure drop you described, you would see a LOT of **** on the pleated filter media, it would literally shine with metal it would be so much, and for an engine to have that much metal or anything else in it, it wouldn't just start and run with no noise........AND.....if it was that low....you would have heard the lifters just clattering away. So no, I don't think your filter was clogged......
A filter is pleated and has that much area so it can never plug.......I have only heard of a plugged filter in engine applications that have MUCH smaller filters......the BBC/SBC filter is huge compared to say, an LS filter......and I have heard of LS filters being plugged due to neglect....AKA sludge....from not changing oil.....
But anyway....cut it open and prove me wrong.
If you have hydraulic roller lifters (like a ZZ4, L98, or any modern engine), my understanding is that you do not need extra ZDDP. That's only for flat tappet cams.
Originally Posted by pspicci
you beat me by a few seconds
Pat
The "flat tappet" is the fuel pump lobe on any cam roller or not. The pushrod is hardened steel.. That lobe may not even be hardened. You want pictures????
Other unknowns: Who knows how many miles the PO put on the engine after the build and whether or not he used any zinc additives or what oil brand he used.
In any case, I’ve already ordered the ZDDP additive and the car won’t be run until I can get that in … and until I’ve cut open the filter and dragged a magnet through the used oil for metal shavings. I will reiterate that the rockers were all snug (not sloppy) when I had the valve covers off the other day. If any cam lobes were wiped or even badly worn down, I should have found some sloppiness, right?
Depending on how far you want to go with this on your unknown build, you can get your oil analyzed for its metallic contaminants. Tells you more or less what's going on inside and what's wearing. I have my analysis somewhere around here, I may look for it.
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Wish I kept that fram filter...I watched the oil pressure get lower and lower on my way up the interstate to my buddies...Now I go with the tall K&N filters not the little tiny girlie filters. https://www.knfilters.com/hp-3003-oil-filter summit lists it for for big block or small block
The "flat tappet" is the fuel pump lobe on any cam roller or not. The pushrod is hardened steel.. That lobe may not even be hardened. You want pictures????
That really makes the case for an electric fuel pump.
Wish I kept that fram filter...I watched the oil pressure get lower and lower on my way up the interstate to my buddies...Now I go with the tall K&N filters not the little tiny girlie filters. https://www.knfilters.com/hp-3003-oil-filter summit lists it for for big block or small block
I wonder why the HP-2002 does not have a bypass valve and the HP-3003 does.
I have the 3003 on my 72 LT-1. Whew.
The HP-2011 on my truck and the HP-1020 or HP-1017 on my C7 GS all have a bypass valve.
Ok....simple.....the pleated filter area would have to be almost 100% plugged to cause the oil pressure drop you described, you would see a LOT of **** on the pleated filter media, it would literally shine with metal it would be so much, and for an engine to have that much metal or anything else in it, it wouldn't just start and run with no noise........AND.....if it was that low....you would have heard the lifters just clattering away. So no, I don't think your filter was clogged......
A filter is pleated and has that much area so it can never plug.......I have only heard of a plugged filter in engine applications that have MUCH smaller filters......the BBC/SBC filter is huge compared to say, an LS filter......and I have heard of LS filters being plugged due to neglect....AKA sludge....from not changing oil.....
But anyway....cut it open and prove me wrong.
Jebby
When the OP said plugged filter, I wasn't thinking the media was plugged. You're right it would take a lot of schmutz to plug the media. I was thinking more in terms of some cheap filter where the media itself broke down and plugged up the passages.
I'm not real familiar with the details, but in addition to the bypass in the filter, there should be a bypass in the filter adapter. Mine was blocked off when I assembled the engine on the concern that they sometimes stick open. Whoever built the OP's engine may have done the same thing. That would explain why a plugged filter resulted in a loss of oil pressure.
Bottom line is there's more to this story.
And since it came up, if anyone is considering oil analysis, I would recommend Blackstone Labs. I use them for my airplane and their service is excellent. IIRC it costs about $30 to have a sample analyzed plus whatever it costs to ship it to them.
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
probably the size of the canister for certain applications limit it...??? Dont know...I use the one with the built in bypass and an adapter without the bypass. OIl gets changed in the spring and depending on the usage maybe in the late summer early fall so Im not worried about the filter getting clogged, but do worry about nonfiltered oil getting to my bearings
Ok....simple.....the pleated filter area would have to be almost 100% plugged to cause the oil pressure drop you described, you would see a LOT of **** on the pleated filter media, it would literally shine with metal it would be so much, and for an engine to have that much metal or anything else in it, it wouldn't just start and run with no noise........AND.....if it was that low....you would have heard the lifters just clattering away. So no, I don't think your filter was clogged......
A filter is pleated and has that much area so it can never plug.......I have only heard of a plugged filter in engine applications that have MUCH smaller filters......the BBC/SBC filter is huge compared to say, an LS filter......and I have heard of LS filters being plugged due to neglect....AKA sludge....from not changing oil.....
But anyway....cut it open and prove me wrong.
Jebby
I’m not trying to prove you wrong. Trust me, I doubt that it’s plugged, too, for all the same reasons you stated. I was merely asking you what YOUR guess as to what the issue is/was.
I’m still at a loss at this time to come up with anything else EXCEPT for maybe a passage in the block that narrowed and narrowed over time (like an artery in the human body) and eventually closed off completely — specifically, the passage that serves as a path to the oil pressure gauge port. But then that blockage magically and inexplicably disappeared — coincidental with a complete oil and filter change — and now oil is flowing normally again to the oil pressure gauge port.
I don’t have a schematic/diagram of all the oil passages in a 1973 350 small block so I don’t know if this passage to the oil pressure gauge is a direct and dedicated passage or if it’s just some tributary/branch of other passages. I’m guessing that it’s just a branch off of some other passages but that’s purely a guess.
Presuming that’s indeed what happened (temporary blockage of some passage), how long before it happens again? *gulp*
Depending on how far you want to go with this on your unknown build, you can get your oil analyzed for its metallic contaminants. Tells you more or less what's going on inside and what's wearing. I have my analysis somewhere around here, I may look for it.
Do you have a source for this analysis? I’m kind of interested. Does it need to be mailed off somewhere (I see a risk with mailing used oil)?
Contact them for a sample kit. You take the sample, fill out the form, seal up the package, and ship it off. The results will come via email in afew weeks.
The greatest value is in watching for changes over time, but it will pick up coolant or fuel contamination, excessive bearing wear, and a long list of other things.
They send you a kit as to how and when to collect the oil and you mail it back. They had about 30 different materials, e.g. copper, silicon that they checked for and gave you a PPM. They flagged any that were out of line. Cost was pretty reasonable. I have no way to choose between Blackstone or Titan. If you still have oil left over from this adventure, that's probably what you want to send them. A fresh oil change wouldn't be very useful in my opinion. Go read the instructions.
Agree with the above. On some of the railroads I was with, we relied on oil analysis rather than a calendar. When you're talking 200 gallons a pop, and a smaller railroad that isn't working the locos 24/7, there's no need to change oil "just because". As said, they will immediately notify you if something serious shows up. And if you do a sample at given intervals, they will show you previous tests as well as the current one so you can see if some level or other is starting to climb.
The way it used to work, and maybe still does, you buy ____ number of kits. When you take a sample (after running the engine, shut it down and drain fresh warm oil) into a small bottle. This gets sealed and there's a label you fill out. That bottle goes inside a larger bottle. I don't know if USPS will handle or if some other carries has to take it.
Not sure if this outfit is even still in business but here's a kit I still have kicking around. Hope this answers some questions.
One more bit of information which adds more detail
Someone along the way (likely the engine builder) chose to block off the built in bypass on the oil filter adapter plate.
Here are 2 images I took during the entire journey I have described in this thread.
I’m not sure if the engine builders intended there to be that pin hole of a gap in their plug but whatever…
If I understand correctly, with that bypass blocked off, it would force all oil through the filter. And since the Purolator filter I had on there also had no internal bypass valve, well, yikes. I’m not sure if I mentioned this or not but the oil that I drained out had less than 1000 miles on it.
Having said all of that, Inwill reiterate that the AC Delco filter I have in there now DOES have its own internal bypass valve.
I’m sure I’ll get a mixture of opinions on this but I’m considering swapping out the doctored oil filter adaptor base that’s in there and installing a replacement which has the bypass valve intact and functional. I’ve seen guys say they block off the bypass valve on the adaptor plate to force all oil through the filter. That sounds reasonable… as long as the filter itself also has an internal bypass valve.
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
ive done it, my buddy that raced methanol engines did it, and his 11 second 377 75 fette has it. Its good for the motors bearing life but you have to use a high end, quality oil filter. The $4 Fram, puralator, stp filters will suck in the cheap cardboard/paper filter element and plug up the outlet. Its not dirty oil, its just the oil that is getting forced through there and cant get through a cheap filter fast enough collapses the element IF you cut yours up I bet thats what you wouold have seen, not bearing material, crud or pixie dust. I just put a brass plug in the filter adapter on my 427 build but I am using the tall truck K&N filter for more surface area and it has a bypass in the filter if the pressure differential is too great.
These racing application modifications are fine for street engines if you are aware of the how and why that its being done and what to do to make it work.
Now it's starting to make sense. I think your next step is to cut the filter open so we can see what was going on in there.
FWIW cutting the filter open and examining the filter media is a required step in every oil change on an airplane. We could probably learn from that. There are filter cutters available to make the job easy. I have a couple of different models.
Now it's starting to make sense. I think your next step is to cut the filter open so we can see what was going on in there.
FWIW cutting the filter open and examining the filter media is a required step in every oil change on an airplane. We could probably learn from that. There are filter cutters available to make the job easy. I have a couple of different models.
I was going to ask the best way to cut it open. I realize a hacksaw or Sawzall would do it but I’m asking about the best way. I’m thinking the best approach would be to cut around the body just adjacent to the crimp where the body meets the base of the filter. I think if I do that, I should be able to slide the body (case) off, leaving the filter element effectively intact. I do not want to buy a filter cutter for this (probably/hopefully) one-time use.
Of course I would ignore any shavings I create during the cutting.
