Hey! New here, I'm having issues with my 1969 327sbc (in a 69 c10). Stock motor no fancy bits. I get 50lbs of oil pressure up top. And i get oil in the front up top. ( little screw leading into main oil galley above timing chain cover) but zero oil to lifters/ pushrods ect... Even running the engine.. No oil. Any help would be awesome!
Not a Chevy expert but I do recall something about the rear cam bearing having to be installed a certain way to let oil to the top end. I'm sure the real experts will be along shortly to prove me correct or likely wrong.
I've read that too.. I haven't dug into the engine. Just cleaned it up. Im getting oil up top to the main oil passage and all the way down it to the front of the motor... But yea could be..im hoping there's a simpler solution. Hate to have to pull it.
The oil pumps up though the pushrods on V8 Chevy engines. Make sure that the pushrods aren't plugged up. I've seen some sbc sludgemobiles that had the pushrods plugged solid with crud. I'd pull a couple of pushrods and look though them to See if they were clear or not. Here is one of the better tutorials on SBC oil passages from Grumpy Jenkins. oil system mods that help | Grumpys Performance Garage he explains it a lot better than I can. In fact back about 40 years ago I think I used his info to explain oil passages when I was teaching. Simple terms that a classroom full of high school kids could understand.
Hey thanks! Ill check out that link! Sorry i should have gave more info initially. The lifters & pushrods are new. ( exactly the same as the old ones) it was not getting oil before i changed them this was the first thing i tried. I've also filled the engine with diesel left it soak for a week. Hoping to clean any passages.. After draining & flushing still no oil to rockers.
Hydraulic lifters? Working? If so you have oil pressure in the lifter gallery and all should be good to that point.
Yea hydraulic lifters.. I ran it for a total of 30 minutes no more than 5 minutes at a time. Alot of lifter clatter the whole time... Pulled the intake pulled the lifters i could push all but 3 down by hand.. & i think those 3 only stayed primed because i was oiling manually. So no i dont think they are working.
Could be an issue with the rear cam bearing or rear galley plugs. There's an oil port in the back where the oil pressure sender normally lives. You should hook up a gauge to that port, use the priming tool to spin the pump and see if you have pressure there. There's also a hidden plug in the block forcing the oil through the filter. Going by memory here but you can look at the oiling circuit diagram.
I always stand new Chevy hydraulic lifters in a clean coffee can and pour oil in it to cover them and let them sit for a while. Then take a pushrod and work each one in the can to make sure it has oil in it. I'm thinking that this engine has an oil problem beyond lifters and pushrods though.
I do have 50lbs of oil pressure up top ( next to dizzy) when runung the priming tool... Really dont want to, but i might just pull it...damn!
I just brought home a perfect running 4.3 Chevy for my 95 1500 pickup. When I unloaded it the crank damper moved forward about 3/32"! Long story short a galley plug on the front of the engine had fell out! One whole lifter galley wasn't getting any oil! It had caused the thrust surface of the crank to wear out on one end! Had to put a crank kit in it. You might pull your front cover & check those plugs behind the cam gear. If it were the rear ones they screw in I think & would be dumping oil on the floor if out. OR maybe cam bushings turned in their bore?
Keep in mind the forum is for American classics 1965 and earlier, The earlier Chevrolet blocks had a different rear cam bearing if I remember right.
I will pull the timing cover & check them.. I know they were in there!.. Buut wouldn't i still see oil coming from #7 lifter bore? the more i look at those oiling diagrams the more confused i become lol.
Ah did i post this in the wrong forum? If so i apologize. I checked the casting # it says 1962. The stamp on the front says 1969.. Cast in 62 & assembled in 69? Idk literally all of this is new to me. Just started getting into it over the summer. I'm a novice.
I'll save you some grief. Read this. https://www.jalopyjournal.com/forum...-journal-327-no-oil-pressure-at-idle.1024437/
The grub screw in the front of the block taps into the main gallery. So you're getting oil to the mains but not the lifters. Are you using a proper oil pump priming tool [or a cut down dizzy]??? If not, oil could be bleeding off where the Dist housing goes through the RH lifter gallery. Incorrect rear cam bearing installment wont cause oil starvation to the lifter galleries because they are all fed from the same groove under the bearing Here is a 327 with the rear cam bearing removed If the rear cam is incorrectly installed on a 327 it only causes oil starvation to the rear cam journal.[eg: the hole in the bearing is the yellow dot]
So to be clear. There is a suffix code consisting of letters and numbers stamped on the pad right below the passenger side cylinder head on the front of the block. That can be decoded to reveal the assembly plant, date of assembly and vehicle application in most cases. There is also a casting date code cast right into the block as well as the block casting number. Almost no way a block is cast in '62 and assembled in '69. Blocks can and have been re-stamped or had suffix codes altered.
I have built lots of sbc's, mostly 327" and 283". I only had one issue like you describe and that was because the shop installed the new cam bearing upside down on the back cam bearing journal. There is a hole on that bearing that must line up with the hole on the block.. Once we put it right side up, oil flowed like we had hit a Texas oil well. See the post 2 ahead of this one. The question is, did you install new cam bearings?
Even if the engine had No Hole in the cam bearing it will still get oil to the lifter galleries.[it only affects the oiling of that particular cam journal] The 327 block has a 360 deg oiling groove machined into it. [The oil comes down from the centre hole out the other 2 holes behind the cam bearing] The only trap is some early cam bearings the groove/hole is offset so you must line up the hole over the groove. Aftermarket early cam bearings have 2 holes so they can be installed either way [only 1 hole needs to be over the groove] Later cam bearings groove are in the centre so they can be installed either way [front or back] @Beng87 The rear plugs could be installed too deep or it has restrictors installed that can be an issue
Hmm this is super helpful! Thanks.. So that center hole fills the main galley? & the 2 on the sides the lifter galleys.. Im getting oil in the main galley up top.
There's alot here.. Sounds like my best option is to pull it and check the cam bearing.. The groove and holes underneath it....
The rear cam bearing only seals the groove. and has a journal/bearing feed hole in it. That groove is a cheap way for GM to machine an oil gallery. Then the bearing seals it from leaking. If the bearing is installed wrong, it will only starve that journal NOT the lifter galleries. What are you using to prime the oil? or are you just cranking the engine over?
I have 2 styles of priming tools one with a wider channel and one with a smaller one.. Neither makes a difference. The dizzy in & running makes no difference either. So i think i can eliminate that.
I also remember something about some people over tapping the rear galley plug holes and installing plugs that were too long which would block oil feed ports.
Stamped or roller rockers? Roller rockers usually are constant feed and require lifter gallery restrictors. Stamped rockers a pulse oiling [they only oil when the pushrod hole and the hole in the rocker align in a certain position]
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