rooster287 Posted February 23, 2009 Share Posted February 23, 2009 I'm hoping someone can help me with a question on engine break in. I have 74 260z with a SBC 350 that i've recently had rebuilt (bottom end only) and today we were supposed to break the motor in. The entire top end had been put on and the cooling system in place and we filled the radiator. The first issue I noticed was leakage from around several freeze plugs. Although it wasn't gushing out, there was a steady drip from at least two of the plugs. We weren't entirely happy about but figured that we could fix it with some Bars leak. Ok so onto pumping oil up into the top end of the engine. We added five quarts of non-detergent oil to the engine and a filter. We then attached an old distrubtor without gears that would engage the oil pump. We also put on a oil gauge outside to be able to read the pressure as we worked the oil pump. We put a drill motor onto the old distrubtor and slowly turned the distrubutor so that the oil pump would push oil through the engine. This was going fine for about 10-15 seconds when the drill motor seemed to "seize". I could see the pressure reading at about 40 and when the drill stopped it slowly fell to 0. I pulled the drill off the distributor and cranked it by hand. Two things i noticed. One, I could get up to 40 PSI with a few quick turns of the distrbutor. The second issue was that the distriubtor was really fighting me so much that after about three turns by hand it wanted to back out - kind of like winding a rubber band. We had the valve covers off and on the several of the push rods oil spurted out. I thought maybe the filter was the issue (wrong type for the car) but verified that I had the proper one installed. I spoke with a different friend who said that there should be no way to get up to 40 psi oil pressure by just turning the distributor by hand. Now i'm wondering if the oil "passages" in the engine weren't propelry cleaned and that the high PSI is from the oil being forced through the clean passages. Has anyone experience a problem like this on break-in with very high oil pressure? thanks! Quote Link to comment Share on other sites More sharing options...
Kingnothing616 Posted February 23, 2009 Share Posted February 23, 2009 Where did you attach the oil pressure gauge to? And on another note.. bars leak is the last thing you want to put into your engine, it generally makes things worse, clogs up the passages in the radiator, yes it "MIGHT" stop a leak, but the adverse effects are far worse. Quote Link to comment Share on other sites More sharing options...
rooster287 Posted February 23, 2009 Author Share Posted February 23, 2009 the oil gauge was attached to the port on the motor where you would put the sending unit. Quote Link to comment Share on other sites More sharing options...
jasper Posted February 23, 2009 Share Posted February 23, 2009 After reading your post, I'm not quite sure you have a problem. I would not be surprised that you could hand crank 40 psi on a cold engine, that wasn't rotating. The initial spinning of the drill will slow down to a crawl, once you fill all the voids and passages, and develop some psi!! Quote Link to comment Share on other sites More sharing options...
jt1 Posted February 23, 2009 Share Posted February 23, 2009 The "rubber band effect" is normal. I've seen several engines do the same. Don't know about getting 40 psi turning the dist by hand. Are you doing it with just your fingers or do you have a speed handle on it? I would probably run the dist with the drill, and turn the motor slowly till I saw oil at all the rockers. Then I would call it good and try to crank it. What kind of break in lube are you using? That is absolutely necessary with a flat tappet cam and today's oil. jt Quote Link to comment Share on other sites More sharing options...
rooster287 Posted February 23, 2009 Author Share Posted February 23, 2009 hi Jt1, we were using just fingers before we put the drill on it. I'm using CompCams break in lube. one item i didn't mention was that oil was "squirting" out of the rocker arms on 1/2 cylinders while the ones towards the back of the motor were hardly a dribble of oil. I'm not sure if the position of the lifters could cause this kind of distribution of oil when priming. Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted February 23, 2009 Share Posted February 23, 2009 There is no problem. The stock oil pump takes about 7hp to turn at any kind of rpm so your wimpy little drill motor won't cut it even at a couple hundred rpm. I use a 1/2 inch drill and it'll wrap you up if your not holding on with both hands. If your running a high volume pump it'll take upwards or 10hp to run it. You can prime it with the regular dizzy just make sure it's not hooked up and crank it. If you built it right with proper lube is shouldn't be a concern, crank it over with the starter and the plugs out till you build oil pressure, put it all back together and start it. Break in, I've heard so much about that and IMO you need to drive it like you normally would with the exception of sustained high rpm. I'd break it in via the cam manufacturers recommendation and then let her rip. They talk about non detergent, regular, EOS, all the additives, etc, but IMO if you lubed the cam and lifter excessively with cam lube, have oil pressure, run it at the right rpm at start up, it'll work. I have had cams go flat, there seems to be no rhyme or reason, even with non detergent oil, eos, mega cam and lifter lube, etc, all cam types, hyd, solid and roller (although roller is typically due to lifer rotation or lifter bind I have seen some that just went flat). Tear it down, change cams with the same exact one but new and no problems, go figure. Quote Link to comment Share on other sites More sharing options...
jt1 Posted February 23, 2009 Share Posted February 23, 2009 All the rockers don't get oil all the time. When you turn the crank two revolutions, the cam turns one, so that should show oil on all the rockers. It doesn't sound like you have a problem, just strong fingers! Crank her up and let it rip! jt Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted February 23, 2009 Share Posted February 23, 2009 All the rockers don't get oil all the time. When you turn the crank two revolutions, the cam turns one, so that should show oil on all the rockers. It doesn't sound like you have a problem, just strong fingers! Crank her up and let it rip! jt True, the oil hole in the lifter only allows oil when the valve is closed or nearly closed, that is a good point you made. Hence my statement that if it was built correctly. Often times alot of builders using stock type ball and rockers do not use white grease or assembly lube on the ball and rockers which is a big mistake and can lead to galling of the ball and rocker. Quote Link to comment Share on other sites More sharing options...
rooster287 Posted February 23, 2009 Author Share Posted February 23, 2009 thanks everyone for your comments. we'll be back in the saddle over the next few days and i'm feeling a lot less nervous about starting the engine for the first time. Quote Link to comment Share on other sites More sharing options...
ZZZeee Posted February 23, 2009 Share Posted February 23, 2009 Charge the battery well... disconnect the coil... crank it with the charger set to "crank" for a minute or so... reconnect the coil and start that puppy uppy!! Quote Link to comment Share on other sites More sharing options...
rooster287 Posted February 24, 2009 Author Share Posted February 24, 2009 UPDATE: Yesterday we ran the drill for a bit longer to finish priming the oil pump and buttoned the engine up. We proceeded to start the engine and take it up to around 2500 RPM to start breaking it in. The engine sounded great! There were no odd noises and it ran very smoothly. We ran into a couple of issues including having our timing gun go out. Also, it appears that I had a crack in one of the lines connecting the tranny to the radiator so I had a pool of tranny fluid under the car so we shut it down after about 45 seconds. Today we'll be getting the gun and fluid lines fixed and going back at it. We did notice that the oil pressure was reading 95 psi. After pulling both valve covers the oil inside the cover on cylinder 7 seemed low (not alot of spalshing inside the cover). Is 95 PSI too high? One of my buddies seemed to think so. Quote Link to comment Share on other sites More sharing options...
jt1 Posted February 25, 2009 Share Posted February 25, 2009 95 psi is pretty high for only 2500 rpm. Since you can get 40psi with your fingers, the first thing I would do is try another gauge. If possible, one you know is working right. Another possibility would be to test your gauge with compressed air, using a compressor with a gauge you figure is about right. jt Quote Link to comment Share on other sites More sharing options...
jack46 Posted February 25, 2009 Share Posted February 25, 2009 ...Since you can get 40psi with your fingers, the first thing I would do is try another gauge. If possible, one you know is working right. Another possibility would be to test your gauge with compressed air, using a compressor with a gauge you figure is about right. jt I don't believe it is possible to turn the oil pump by hand and achieve 40psi...the guage is wrong. SBC can often have 80 psi start up cold and barely get to 60psi when at operating temps Good luck let her rip keep RPMs up if non roller cam for ~20 minutes Quote Link to comment Share on other sites More sharing options...
rooster287 Posted February 25, 2009 Author Share Posted February 25, 2009 UPDATE 2: So yesterday we threw caution to the wind, fixed our leaky transmission and started the car up. The engine fired right up and we immediately started breaking the motor in for about 25 minutes. Our timing light took a dump again so we couldn't set the timing but the car ran awesome! After shutting her down and checking the valve covers for oil we buttoned the engine back up and fired it again. The engine started right up again and had a nice subtle lope at idle )) (big grins here). I think we have a winner! I wanted to thank everyone who posted and i'll be uploading pics / video in a few days. Quote Link to comment Share on other sites More sharing options...
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