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By MoonShadow - 9 Years Ago
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I recently had to replace the head gaskets on my 292. Prior to switching them I had no problem with rockers getting oil although pressures were a bit low. Now I find the passenger side is not getting oil. I pulled the rocker shaft this am and found one rocker was split and several had galled the shaft. I didn't make any other changes so why am I having oil problems now? Front cover wasn't off but the rockers were. I checked and the feed holes are lined up and I get good air through the shafts. So any ideas? Hoping for a simple fix, expecting bad news though. Chuck
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By charliemccraney - 9 Years Ago
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Nah, totally normal for a demon spawn motor.
The passenger side is the first to go. How low is the oil pressure?
Maybe some trash clogged the hole before it was reassembled.
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By topgun1 - 9 Years Ago
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I just read something on another site. One guy said the front and rear head bolts under the valve cover are longer? He said it could cause an oiling problem. Not sure if he's correct. I thought I would throw it out there. 
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By MoonShadow - 9 Years Ago
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Those two bolts are longer but I don't think they would cause an oiling problem. Just wouldn't clamp the head correctly. Charlie may have it with something plugging the feed hole. Hate to pull this again this year! Tomorrow I'll pull the rocker shaft and put some air pressure on the block side of the feed hole. This engine does seem to be a demon. I've rebuilt it and had it balanced twice. Never seem to get a full year on it. First repeat was the number 2 main bearing had spun. Tore it down went all the way through including a line bore and since then its always had low oil pressure when idling hot. I blew a head gasket this year and tore it down to replace them. While it was down I pulled the pan and re torqued the mains and rods, cleaned out the oil pan and put on a new oil pump. I added a couple washers behind the oil pressure relief spring to bring the pressure up. Now it runs at about 40lbs and idles hot at 15lbs. Had a noisy rocker so I decided to pull the covers and adjust the valves that's when I found the lack of oil on the passenger side. I've replaced the rocker assembly with a spare but still no oil. I'm a bit disgusted with the whole affair now.
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By Ted - 9 Years Ago
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When the oil to the right side (pass side U.S.) rocker arms is diminished or quits, cam bearings are at the top of the list. But not to be discounted is any kind of restriction in the oil galley in the block or the heads. And if the heads have been heavily milled, then an oil flow problem in the slot on the deck surface of the head is another possibility. Assuming the rocker shafts have been disassembled and given a clean bill of health, I’ll suggest pulling the distributor and priming the engine with the passenger side rockers off and observing the amount of oil actually coming from the rocker pad at the top of the head.
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By charliemccraney - 9 Years Ago
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My engine has always had about 15psi at idle and 45psi at speed, hot. I've thought that seems low but I've never had problems about oil getting to the rockers.
It's been the same story with two builds of the engine and the only things common between the two that could have an effect on oil pressure is the block and the guy who put it together (me).
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By MoonShadow - 9 Years Ago
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Well its confirmed the Demon Spawn engine is indeed the work of the devil. Took off the rocker shaft and blew compressed air into the oil feed hole. There was no back pressure on the air gun and I could hear faint sound of air blowing inside the engine. Hooked up a start switch and cranked it over while watching. Absolutely no oil is coming up to the rocker stand. I stuck a wire through the feed hole and it went way in past the gasket surface so it not a gasket problem. Obviously the "easy fix" ain't gonna happen on this one. The first rebuild I had a shop do all the work and balance it. I assembled it myself. After the main bearing problem (less than 500 miles) I took it back for repair and freshen up. The Y-Block guy at the shop took care of it. While fitting the rings he decided since the pistons and rods were going in he put it together for me. This block and all parts were hot tanked both times. Once back in the car I was seeing the low oil pressure I mentioned. I didn't put another 500 miles on it this time before the head gasket blew (mostly because of using G heads with a McCullouch supercharger). There is nothing physically obvious about this engine except it has some sort of oil problems. I'll have to park it for the winter. I'll work on the throttle linkage and other setup items for the new blower motor and put it in next spring. I'm hoping to get this problem engine down to Ted next year and have him go through it just to see what he can find. I hate problems without explanations! Like why did I have no rocker oil problem until I did the head gaskets?
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By Ted - 9 Years Ago
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Another thing to check is gasoline contamination of the oil. If you have changed the oil since your recent road trip, then you can probably discount this.
I would send you a high volume oil pump to try but it’s already loaned out to someone having a similar low oil pressure problem. A high volume oil pump (20% additional oil volume) may be just enough to overpower whatever fluid loss that’s taking place that has in turn lowered the overall oil pressure to the point that the rockers are no longer getting oil. If you’d like to try your hand at making your own high volume oil pump, here’s the link.
http://www.eatonbalancing.com/blog/2014/09/19/hi-volume-oil-pump-for-the-y/
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By Ted - 9 Years Ago
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I’ll suggest also double checking the flange nut at the oil pump. Pulling in just a little bit of air at that point can significantly lower the oil pressure.
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By speedpro56 - 9 Years Ago
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You're right on that one Ted, had that happen to me. Man what a relief it was when I found it!
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By 2721955meteor - 9 Years Ago
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nut for oil suction is important,as over lightning will crush the tube,i made a tool to drive into the tube while heating it to reshape(pan off) then do not over tighten i snug the nut if it drips over night just a small amount of tighter till no drips. i do not use the ring with the metal crush sleve. runs 25 psi at idea 55 to 60 hot.run 5/30 oil,with gear typ pump.
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By PF Arcand - 9 Years Ago
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Meteor is quite possibly on to something there. A replacement pump I had here came with a tag which stressed making sure that pump seal is installed straight & carefully snugged into place.
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By Ted - 9 Years Ago
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Ted (9/17/2016)
I’ll suggest also double checking the flange nut at the oil pump. Pulling in just a little bit of air at that point can significantly lower the oil pressure.
I liberally coat the rubber grommet with white grease before installing it on the tube and into the pump housing.
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By DANIEL TINDER - 9 Years Ago
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Ted,
Instead of axle/bearing grease? White grease couldn't contaminate the oil then?
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By DANIEL TINDER - 9 Years Ago
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Oops. Sorry. Confused about which surface exposed. Still, question is relevant for pan/valve cover gaskets, etc.
Is white grease contraindicated for surfaces exposed to circulating engine oil?
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By Ted - 9 Years Ago
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DANIEL TINDER (9/18/2016)
Ted, Instead of axle/bearing grease? White grease couldn't contaminate the oil then?
I’ve no problem with using axle bearing grease as an oil pump rubber seal lubricant as long as it’s clean and not used in excess. Depending upon the brand, it may have a higher melting point and could ultimately end up in the oil filter or in the bottom of the pan if used in an excess. But simply using it to coat a rubber seal should not be considered an excessive amount.
The white grease I use is clean (Lubriplate brand) and has a lower melting point than the typical wheel bearing grease. If a little bit of it ends up in the oil, then it’s fully melted at 140°F and essentially of no consequence. While I use white grease as a sealer on some of the various gaskets and seals, I do not use it on engine bearings or as a cam lube. It can stop up the oil filter if used in excess and if used as an engine assembly lubricant for the bearings, then the potential is there to hydraulic the bearing surface if it cannot squeeze out adequately when the various bearing caps are being torqued in place.
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