MID12sSSS Posted October 5, 2012 Author Report Share Posted October 5, 2012 Hmm.. shit. I hope im not dealing with a bearing problem then. I was hoping the pump was making the noise ive been chasing, as it doesnt sound like a bottom end noise. If i dont figure it out soon, im gonna have to pull it and call in the experts. Quote Link to comment Share on other sites More sharing options...
KrausMotorSports Posted October 5, 2012 Report Share Posted October 5, 2012 First off! Take a deep breath and walk away for a few minutes. Lol at least it works for me. I'm not a professional engine builder but have built quite a few for myself and friends. . But I do know this! If it's a brand new engine with aluminum heads. You are supposed to retourque them to specks after initial break-in. Could be the cause of possible valvetrain noise but doubt it in this situation. This is on old school small and big block CHEVY's and occasional fords. I would pull what you can off the front of the engine before yanking the whole thing. And check that cover. Was there anything else you did check? End play/ new rodbolt clearances? Quote Link to comment Share on other sites More sharing options...
MID12sSSS Posted October 5, 2012 Author Report Share Posted October 5, 2012 I pulled the front cover the other weekend, hoping to find some scuffs or marks where something may have had clearance issues (such as the double roller timing set). Didn't find much. Then I pulled the oil pan and inspected the windage tray for marks. Still nothing. You cant hear the noise when you turn the motor by hand or while cranking. But once it's idling you can definitely hear it. I was so convinced the rod bolts were tapping the windage tray somewhere, since you could only hear it at idling and higher rpms, but not at cranking speed ( thought clearance wasn't enough to compensate crank stretch and so it was tapping). But nothing. It's loudest in the front of the oil pan (using a stethoscope). I put the stethoscope on the front cover and its not very loud, but I touch the front of the pan and both side of the front of the block, near powersteering and A/C pumps, and its very loud. I ran the motor with the belts off to eliminate the accessory pumps and pulleys. The noise still exists. I disconnected the ignition coils one at a time, to see if it was a slight rod knock. The noise didn't quiet down at all. And everyone I've had give me their .02 ( shop foreman and other techs), they're all convinced its not a lower end noise. So I checked base oil pressure, found it to be low and priming slowly, but as stated above, I'm using the stock red o-ring, not a green one, with the slp pump. I have got to get rid of this noise. I couldn't imagine it's a bearing clearance noise or anything like that, but I guess the only way to find out is to get in there. Gonna put my stock pump back in this weekend and take a look at the rod bearings and rod cap side to side movement while I've got the pan off. I've seen a few posts on forums that describe a Diesel engine like sound, loudest in the front I the oil pan, being caused by a bad oil pump. So I'm keeping my fingers crossed for that. Any other ideas that I should keep an eye out for while I'm in there? Quote Link to comment Share on other sites More sharing options...
Cramer Posted October 6, 2012 Report Share Posted October 6, 2012 The sound might be the lifters not pumping up. The sound they make can radiate through the engine and be hard to pinpoint but if the sound is consistant with a valvetrain noise I bet this is it. The pump isn't providing enough pressure to them. If the o-ring is pinched or not the correct one in the pump it will suck air in along with some oil giving you pressure but areated the oil. Use a NEW RED o-ring with the stock pump. I really think the SLP pump is ok but it is a issue with the o-ring. Quote Link to comment Share on other sites More sharing options...
MID12sSSS Posted October 6, 2012 Author Report Share Posted October 6, 2012 The sound might be the lifters not pumping up. The sound they make can radiate through the engine and be hard to pinpoint but if the sound is consistant with a valvetrain noise I bet this is it. The pump isn't providing enough pressure to them. If the o-ring is pinched or not the correct one in the pump it will suck air in along with some oil giving you pressure but areated the oil. Use a NEW RED o-ring with the stock pump. I really think the SLP pump is ok but it is a issue with the o-ring. I'll definitely throw a new pump in it tomorrow, but if it was lifter noise, wouldn't I be able to hear it at the valve covers with a stethoscope. That's why I suspected the pump, but thought it was weird that I couldn't hear anything at the front cover, but like you said, noise carries through a block. There is airspace between the front cover and oil pump, so you won't hear it as well, but the pump is bolted to the block so its loud as hell in the front of the pan and sides of the block it bolts to. Maybe it's the same with the lifter. Could be hearing the noise through the cam, behind the front cover, but can't hear anything at the heads. Engine are such a pain! Haha. Quote Link to comment Share on other sites More sharing options...
Cramer Posted October 6, 2012 Report Share Posted October 6, 2012 Do not reuse your old oil pump pick up tube o-ring if you didn't already know. I would also change the oil and look for any shiny shavings or anything out of the normal in the pan or filter. Take a extending pencil magnet and reach around in the oil pan with it and pull it out a few times. Mainly looking for lifter material like some bearings or at the worst the parts of the roller. If nothing is found hopefully no major damage was done. Quote Link to comment Share on other sites More sharing options...
MID12sSSS Posted October 7, 2012 Author Report Share Posted October 7, 2012 (edited) Installed new oil pump with new pickup tube o-ring. primed motor by pulling fuel pump relay and doing 5, 5seconds cranks. Put relay back and fired it up. Instantly i hit 45psi. So my base oil pressure problem is solved.. But the motor still sounds like a diesel. I dont know if its the timing chain or a bearing, or lifter, but the sound may be a repercussion from running it without good oil pressure, or maybe, i havent run it long enough with good oil pressure for the noise to go away? I didnt run it very long today once i could tell the noise still existed. I took a quick clip with my phone so you guys could listen. http://s1244.photobu...nt=IMG_0942.mp4 video is choppy on photobucket, but the audio is pretty clear. Sound is loudest in front cover, front of oil pan area. I appreciate all the input you guys have been posting. Thanks again. Edited October 7, 2012 by MID12sSSS (see edit history) Quote Link to comment Share on other sites More sharing options...
The_aSSet Posted October 7, 2012 Report Share Posted October 7, 2012 That does sound like a diesel lol wtf that's weird. Everything should've primed up pretty quick I would think. Quote Link to comment Share on other sites More sharing options...
gmJake Posted October 7, 2012 Report Share Posted October 7, 2012 That is a loud click from the right bank. Quote Link to comment Share on other sites More sharing options...
MID12sSSS Posted October 7, 2012 Author Report Share Posted October 7, 2012 Haha yeah. Any ideas? Quote Link to comment Share on other sites More sharing options...
shawnss Posted October 7, 2012 Report Share Posted October 7, 2012 Wow sorry to hear this that really sucks. how many miles do you have on it now sense the build? from the go did it have low oil pressure right at the build? It seems like when you have rod knock the bottom end won't stay together long. i have had rod knock in 2 honda in the past and tried to baby is home and it didnt make it far. ended up sending a rod through the block. what did you do to the motor stroker or just a rebuild? i once had a similar noise coming from my 6.0. i was sure it was a rod knock. it ended up that the skirt of the piston was coming down and touching the courter weight of the crank. ill see it i can find a video i took of it. Quote Link to comment Share on other sites More sharing options...
MID12sSSS Posted October 7, 2012 Author Report Share Posted October 7, 2012 Just a rebuild. Stock displacement but went with a forged rotating assembly. There is about an hour of run time on it now. All idling, minus about 10 seconds of 3000 rpm. All of the run time was with about 20 psi of oil pressure. It's a low number compared to 45, but I wouldn't think 20psi would cause any engine damage. I could pull the motor and put all new bearings in it, but I'm not sure if its a rod knock. I don't think it is, but who knows? I'll have to have the machine shop put some cam bearings in as well, if that's what it comes too. I'd rather save the motor I got, than run it and throw a rod and need to replace everything. Quote Link to comment Share on other sites More sharing options...
KrausMotorSports Posted October 7, 2012 Report Share Posted October 7, 2012 As far as engine building goes its always been a rule to have at least 10lbs of oil pressure per 1000 rpm. You should have been okay with the 20psi you had before. If you do pull it out I know when I worked at the machine shop we would assemble the short block for you, which we gave all clearances and specs on all tolerances for insurance purposes. We also warrantied them as well. Is there a shop nearby that can do that for you? Save you a hassle and have some insurance? I know forged bottom ends are $$$. And I believe the bottom end assembly was around 250 or so. Quote Link to comment Share on other sites More sharing options...
The_aSSet Posted October 7, 2012 Report Share Posted October 7, 2012 Stock pressure is around 40 ±5 at idle. 20 seems pretty low at idle but I've heard different things from different builds. Since its just a rebuilt to stock specs 40 should be where it should be. But that's all my opinion lol I could be wrong Quote Link to comment Share on other sites More sharing options...
AKSSS Posted October 7, 2012 Report Share Posted October 7, 2012 Northern machine on Davis did my short block. They do good work. Quote Link to comment Share on other sites More sharing options...
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