brokenjeeper
So I have the 401 assembled on the engine stand finally, and fill 'er up with oil + break-in additive. I install the oil pump primer and proceed to run in up with a 1/2" drill. After half a minute or so I feel the pump get oil and continue priming watching for oil to reach the rockers. Nothing after a couple of minutes, so I rotate the engine by hand 90 deg. and spin some more. Still nothing, so I rotate another 90 deg. and spin some more.....until oil starts coming out of the water pump at the lower radiator hose connection???? What gives? Before I tear this down again, I would like to have some idea of where the oil blockage might be. I remember a vague mention of some plugs behind the timing set being of different lengths? Would that completely obstruct the oil passage and create enough pressure with a drill to force it into the water pump? I did opt to install the valley oil line, but everything looked good. Your help, as always, would be greatly appreciated.
For the sake of continuity I am posting this here vs. the Oiling board. After disassembling the engine, I opted to leave out the valley line and plug the holes vs. drilling on the assembled block. I also took some time to double check all of the oil galley plugs, lifters, etc. I reassembled everything and filled the engine with Joe Gibbs break-in oil and primed up with the drill. I could feel the pump grab prime after just a couple of seconds, but after several minutes spinning with a Milwaukee @ around 1300rpm I still had no oil to the rockers which were also checked to be clear. Long story short, I have disassembled the oil pump, re-checked cavity clearances (right at .0045) and blown air through the pressure and suction ports to ensure they were clear, checked pressure bypass for free movement, filter bypass was rechecked, reassembled with still no oil to rockers. The gears(Melling) were new and gone over thoroughly with all nicks hand stoned and polished to include the shaft running through the timing cover. The cavity was in good shape with very minor scoring on the leading edge of the suction side of the drive gear. I am using a steel midplate as well. The engine was turned over four times by hand in 90 deg. increments during priming. At this point, some of the lifters have pumped up slightly, mostly on the driver's side, and I am getting a steady drip from the cam gear. There is no evidence of oil seepage past the oil gear drive shaft into the timing cover, and my mech. gauge is registering approx. 5 psi (it barely moves off 0). Removed, the gauge line gives a steady drip as well, but not as much as is coming off of the cam gear. I know the oil pump has good suction because I spun it with the filter removed to check flow, and it seems to be pumping into known clear passages (including the coolant passage previously), so what am I missing? Timing cover out of spec., or bearing installation issue? Your help, as always, is appreciated.
jeepsr4ever
Bad gasket or cracked timing cover.
ironman_gq
There is no connection between the oil passages and the water pump so for oil to be coming out of them you must have a crack somewhere or a bad gasket. Find the source of the oil intrusion and you will probably have found your problem. as far as the pushrods go pull one out and see if there is oil getting to the lifter end of it and look through all of your pushrods to make sure the passage through them isnt plugged. I had several new pushrods come with metal shavings inside them that would have blocked oil flow if I hadnt found em before I put it together :lo1l:
brokenjeeper
Thanks for the quick reply MC. While disassembling the engine I drained the oil and got back 3 qts. Figuring a qt. or so for the filter, and I pumped a good qt. into the coolant passage/water pump. Concerning the bad gasket/cracked timing cover, I'm a little confused as to where the oil might enter? The oil passages to and from the oil pump seem a good ways from the coolant passages. I also used RTV around the coolant passages where they meet the timing cover and they appear intact externally with no external oil leaks anywhere on the engine? At what point would the oil enter the water pump under pressure, never having made it to the rockers? Is there a chance the valley line mod. was drilled into a coolant passage? I'll post some pics. as soon as I reset photobucket.
jeepsr4ever
Holy cow something is missing or damaged somewhere!! Is this a new timing cover, what intake?
brokenjeeper
The timing cover is used, but appeared to be in good shape. The pic. is of the valley line as installed by the machine shop. I'll know more tomorrow when I disassemble more, but I would like to know where to look or what to look for. The block came back as a short block and looked good from what I could tell then, so me looking at it some more looks like a hit or miss proposition right now.
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jeepsr4ever
Hmmm nothing there looks wrong
brokenjeeper
Just FYI, the pics. are from the initial assembly. I haven't torn it completely back down, yet. As per ironman, I did check the pushrods prior to install and ensured they were clear. I'm just curios what might be missing , broken, or misinstalled besides the timing cover. I can't see even a cracked cover allowing a quart of oil through with a drill, and the crack would have to be small enough for me not to notice it. The block was magnafluxed @ the shop and did reveal a small crack on on the 7 main where the oil passage is, but not a deal breaker by any stretch, and nowhere near a coolant passage. With any luck I'll know tomorrow, but I wanted to pass it by the experts to keep from having to tear it down more than I need to.
ironman_gq
pull the timing cover and see if the oil is coming from the water jacket of the block or from the cover. you should be able to see the oil residue anywhere it went that it shouldnt have been. Is it possible that the oiling line mod was drilled too deep and hit a water passage?
brokenjeeper
So, I finished tearing the engine down some more. After pulling the timing cover, I noticed the oil seemed to be concentrated on the driver's side water port of the engine, but a closer inspection revealed puddles of oil in the passenger side water passage. I guess the oil must have flowed over after filling up the water pump. I pulled the manifold and removed the line and fitting in the lifter valley. At first, I couldn't really see anything because there was a puddle of oil which I thought was a good thing, figuring that if there was a hole into the coolant passage it would have drained into it. But, no such luck. I blew some air through it with a compressor only to watch a nice puff of oil vapor shoot out of the passenger side water port. I'll talk to the machine shop to see if there is a fix and if they are willing to make it right. Thanks again for all the responses. I had kind of a sick feeling that it was in fact the valley line, but I was hoping there might be something else. I'm glad at least I found it now vs. later....
tufcj
Looking at that pic of the block again, the rear fitting IS IN THE WRONG PLACE.
It should be BETWEEN the lifters. It's definitely in the water jacket where it is.
Might be as simple as a pipe plug, but it would always be something I would worry about leaking.
Bob
tufcj
brokenjeeper
Right, after closer inspection now that I've calmed down a little, it doesn't look too bad. The fitting is drilled smack dab into the coolant passage using one of the raised bosses that run the length of the valley. I believe I can epoxy a pipe plug into the hole. The only real issues I have is deciding whether or not to drill the new hole and worry about drill shavings, getting new gaskets and cleaning the parts once again, reassemble, and of course getting the oil out of the coolant passages. Could have been worse. Live and learn , I guess.
brokenjeeper
tufcj
I certainly wouldn't drill/tap the oil hole in an assembled engine. The metal chips would do more harm than the line will do good.
If a shop did the job, I'd make them disassemble it completely and re-do it right. The couple of engines I've done with that mod, I did the drill/tap before the block was tanked. The last engine I built, I just used the reduced hole cam bearings without the oil line. So far, so good. (about 2000 miles).
If you're done with the shop, and you won't be running high revs for extended periods, you're better off to just plug the holes on both ends and call it good.
These engines ran years without that oiling mod. If it's rebuilt to factory spec and not overly abused, it will be fine.
Bob
tufcj
46flattie
What a bummer. I agree w/TufCJ, but if you decide to reinstall the oil line, with a little careful planning I have done it successfully. Remove the lifters on the affected oil galley side, flush valley and the oil galley w/brake clean or other solvent to remove any oil residue, cover lifter bores, and use a vacuum to suck up the chips while your drilling and tapping. Also run a magnet down the oil galley to pick up any chips that the vacuum missed.
I would go after the machine shop for a new gasket set at a minimum. Unfortunately, it's hard to put a price on a 401 block.
djaponi3
thanks for helping me decide to leave my block oiling routing alone! I will use the bulltear cam bearings! by the way my machinist asked me what kind of rockers I will use with these reduced oil hole cam bearings he stated stock rockers might not be happy with em and said roller rockers would be better choice!
73hornut
Whoevr drilled that, missed the lifter galley and drilled into the water jacket. The lifter galley is the hump below that hole.
ironman_gq
your stock rockers should be just fine with the small hole bearings just make sure they are put in right I think there are two sets of holes on them one is the stock size the other is smaller. the oiling system on these motors favors the valve train over the crank so it can handle a little less oil
djaponi3
front bearing uses larger oil hole correct?????????
brokenjeeper
TTT with a new, or maybe ongoing, issue.
