Top End Oiling Issue – SBC

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btwick
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Top End Oiling Issue – SBC

Post by btwick »

Hoping for help with a top end oiling issue on a new motor. Some background:

• 383 SBC bottom end assembled by shop. 1996 and up, OEM roller block
• Eagle rotating assembly w/10.5:1 comp
• ProMaxx 2169 heads
• Cam is Comp hyd roller
• Lifters are Sealed Power HT 2148 OEM rollers, using OEM collars and spider clamp
• Push rods are aftermarket
• Rockers are Comp stamped steel (1.6), roller tips, with grooved pivot balls
• Oil pump is Melling high flow

At first prime, didn’t get oil to top end of motor. Was advised to run it anyway as sometimes SBCs can do that. Ran it on a stand and eventually got oil spray out of the push rods, so it went in the car and driven for ~100 miles.

Pulled the valve covers off and found 8 of the 16 rockers had blackening and light bluing on the bottoms. Balls seemed darkened in spots as well. No bias on either bank of cylinders or intake vs exhaust--random.

Motor was out of car for another reason and inspected the oiling system. Have checked:

• All plugs are correct in block
• No oil restrictors as far as I can tell
• Groove on aftermarket HEI dist looks normal
• Pushrods are clear
• Lifters fit in bore as well as I can tell without proper measuring tools
• Oil pressure is 25 at idle and 50-65 with revs

Bought a new set of rockers/balls and ran the motor on a stand without valve covers. Was getting droplets spitting out of the pushrods. But, no real flow.

Thinking I was OK (yeah, not smart), put the motor back in and drove it for ~30 more miles. Pulled the valve covers and rockers again and found the same darkening of the bottom of 8 rockers and some galling of the balls. Other 8 look fine. Again, in a random pattern of intake vs exhaust rockers and sides of motor.

Also have an oil burning issue and in the process of trying to solve that, found my rocker studs were not sealed properly. But, don’t think either of those are related to lack of oil on the top end.

Could it be the channels in the lifters don’t match the galley channels in some bores? Try new lifters? Could it be the oil filter adapter dumping pressure, but that would reflect on my gauge, right? Anything else I am missing?

Thanks, Brian
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Re: Top End Oiling Issue – SBC

Post by In-Tech »

Many times, the "anti-gall" rocker balls don't match the radius of the stamped aftermarket rocker. These have to "break in" requiring plenty of zddp.
Many times the pushrods told to run are too long by at least .100. 7.200" rings a bell for stocker factory hyd roller with higher cam lift than stock.
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btwick
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Re: Top End Oiling Issue – SBC

Post by btwick »

In-Tech wrote: Mon Aug 02, 2021 11:21 am Many times, the "anti-gall" rocker balls don't match the radius of the stamped aftermarket rocker. These have to "break in" requiring plenty of zddp.
Many times the pushrods told to run are too long by at least .100. 7.200" rings a bell for stocker factory hyd roller with higher cam lift than stock.
Thanks. Balls and rockers are Comp, should be OK. Still running 2X zinc oil, and measured the pushrods with running cam and rockers, and wear pattern on valve tips are centered.. So OK, on those fronts.
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Re: Top End Oiling Issue – SBC

Post by jred »

been building sbc chevys for 40 plus years I have had 2 engines that have had a self induced
problem ,, when installing cam bearings you have to make sure that the #5 cam bearing is not only in far enough but that the cam bearing completely covers the oiling groove in the block,,If not you can have low oil pressure or no oil pressure to the top of the engine..
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Re: Top End Oiling Issue – SBC

Post by BillK »

Another thing to look at is if the pushrods are actually aligning with the oil hole in the rocker correctly. Watch I through its entire travel. I had a very early set of the Comp roller tip rockers that were not made correctly and the pushrod simply was not aligning with the oil hole enough to get any flow.
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Re: Top End Oiling Issue – SBC

Post by BillK »

One more thing, I know that the oil hole in the lifters is supposed to face "up" when you install them. Not really sure what happens if you dont.
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Re: Top End Oiling Issue – SBC

Post by btwick »

BillK wrote: Mon Aug 02, 2021 12:22 pm One more thing, I know that the oil hole in the lifters is supposed to face "up" when you install them. Not really sure what happens if you dont.
Funny you should mention that. First installed them down thinking gravity in the galley could help fill the hole, but then switched them to up after some research. Learned having the holes up (theoretically) allows them to hold the oil better, as down has the potential to leak oil out of the hole. So yes, the holes are up..
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Re: Top End Oiling Issue – SBC

Post by rebelyell »

as you ID'd ... OF adapter bypass
as jred mentioned ... cam bearing placement

Oil pickup tube ... if it's cracked, or not seated & sealed into pump, it Will suck mostly Air & little oil. FWIW, sbc & bbc pumps are great at pushing oil but lousy at sucking oil.
Rarely does a street motor come close to Needing an HV pump. Note how years ago GM upgraded OE sbc from M55 (5/8" tube) ... to M155 (3/4" tube) ... because GM & Melling found the larger diameter 3/4" tube helped pump draw oil at low to mid rpm. Melling offers M155 and a range of 3/4" pickups for M155; GM likewise. I've learned from that & no longer install new M55 ... only pumps with 3/4" inlets.

Run from whoever advised: Was advised to run it anyway as sometimes SBCs can do that... let 'em gamble w/ their own stuff
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Re: Top End Oiling Issue – SBC

Post by PRH »

Try priming with the rearmost lifters/pushrods all the way down(will likely requires doing each side separately).
You’re looking to see if you can obtain proper oil flow through that one pushrod.

We haven’t run into this yet with hyd rollers yet, but we have had some SFT lifters where the oil band wasn’t correct, and when the lifter was near the top of its travel, it blocked off the oil going forward past it. Each successive lifter also blocks the oil going forward.

The rear rockers got oil fine, but you had less and less going forward from there.
The fronts were basically running dry.
Somewhat handy with a die grinder.
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Re: Top End Oiling Issue – SBC

Post by PRH »

Try priming with the rearmost lifters/pushrods all the way down(will likely require doing each side separately).
You’re looking to see if you can obtain proper oil flow through that one pushrod.

We haven’t run into this with hyd rollers yet, but we have had some SFT lifters where the oil band wasn’t correct, and when the lifter was near the top of its travel, it blocked off the oil going forward past it. Then, each successive lifter also blocks the oil going forward.

The rear rockers got oil fine, but you had less and less going forward from there.
The fronts were basically running dry.

In our situation, the length of the oil band on the lifter was too short, with the lower edge of the band being too high.

Edit:
Of course, after thinking about it........
If the oil supply to the hyd roller lifters was compromised....... the hyd portion of the lifters shouldn’t be functioning properly, and they’d be noisy.
Somewhat handy with a die grinder.
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Re: Top End Oiling Issue – SBC

Post by prairiehotrodder »

i had a similar problem. I put together the top end dry, pre-oiled it and oil came up. However it burnt up a couple stock rockers. Switched to comp magnum rockers, they turned blue and started to get chewed up. Replaced them with the comp roller rockers and never had a problem again. Always had lots of oil at the top end but the sliding ball type rockers just couldn't handle the friction. Could have been a combination of having more spring pressure than a stock motor ( mild cam, stock edelbrock E-street heads) or maybe the oil just isn't meant for that type of friction anymore. Do not know. But roller rockers fixed it.
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Re: Top End Oiling Issue – SBC

Post by PRH »

The issue with the motor that had the problematic SFT lifters in it was that it kept eating up pushrods.
It already had roller rockers on it.
Somewhat handy with a die grinder.
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Re: Top End Oiling Issue – SBC

Post by btwick »

prairiehotrodder wrote: Mon Aug 02, 2021 4:14 pm i had a similar problem. I put together the top end dry, pre-oiled it and oil came up. However it burnt up a couple stock rockers. Switched to comp magnum rockers, they turned blue and started to get chewed up. Replaced them with the comp roller rockers and never had a problem again. Always had lots of oil at the top end but the sliding ball type rockers just couldn't handle the friction. Could have been a combination of having more spring pressure than a stock motor ( mild cam, stock edelbrock E-street heads) or maybe the oil just isn't meant for that type of friction anymore. Do not know. But roller rockers fixed it.
Brian
Thanks everyone for the tips. Couple thoughts.. Spring pressures are 145 closed, 325 open, and perhaps pivot balls don't like it?

But, still more worried about flow. Motor running without valve covers had spitting droplets. Watched a video of priming a sbc with drill, and saw oil flowing out, enough to fill the rocker cup. If the spitting droplets were flying up against the valve covers, can't see them filling the cup to lube the ball. Heard about valvetrain oil deflector plates from Moroso, but not thinking that would be sufficient.

Anyone run a motor with no valve covers, or cut ones? Does it flow out and fill the rocker cup, or spray droplets around?
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Re: Top End Oiling Issue – SBC

Post by allencr267 »

Should flow like Niagara Falls, but on a bad day :wink:
Adjusting valves with the engine running, SOP in the 60s, would lose a Qt if you didn't use these little clip-on deflectors on the rocker and then it was still a MESS.
//
//
Qt is a bit exaggerated, but it sure was a lot IIRC.
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Re: Top End Oiling Issue – SBC

Post by smeg »

Try taking the rockers off and then primimg with just the push rods in, you can then see if the flow is better. This will tell you if it is a rocker problem.
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