Author Topic: LQ4 OILING ISSUES  (Read 2727 times)

Offline LSXCHEVY

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LQ4 OILING ISSUES
« on: May 12, 2015, 11:11:39 AM »
I recently got my shortblock back from machine shop, guy says that piston to bore clearance was too much...I have since installed new pistons and had it bored 20 over (or vice versa).. my question is that I bought the DJM stock oil pump (bad move) and had pressure problems from the beginning, would the piston jumping around in cylinder cause the rod bearings to get chewed up?(see pics, this only after a couple hours of running and all bearings were brand new) could it have been the oil pump?, I just purchased a Melling 10296 this time. another question that I have done research one but find conflicting answers is do I need to prime this motor first? I didn't prime first time but oil pressure jumped to 60psi on first start after a few seconds of running.. does anyone run VR1 in their motor?

PS. I am not a CPU expert but how do I get pic size down to be allowed to attach? or is there another way?

Offline Car10s

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Re: LQ4 OILING ISSUES
« Reply #1 on: May 12, 2015, 07:33:13 PM »
I use photoshop. It works well
Floor IT!!

Offline frotosride

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Re: LQ4 OILING ISSUES
« Reply #2 on: May 12, 2015, 08:37:27 PM »
would the piston jumping around in cylinder cause the rod bearings to get chewed up?
  Yes and if you check for shavings in your oil it will be obviouse.
(see pics, this only after a couple hours of running and all bearings were brand new) could it have been the oil pump?, I just purchased a Melling 10296 this time.
Often times this is caused by improper attention to the oring that seals the pickup tube to the pump and or the tube shifted during pan instalation.
 
another question that I have done research one but find conflicting answers is do I need to prime this motor first? I didn't prime first time but oil pressure jumped to 60psi on first start after a few seconds of running..
if the motor was a fresh build and high quality synthetic assembly lube was used on all parts you may be safe but its still really risky business especially with new parts getting to know each other/seating. It is always bad practice not to prelube an engine after any lengthy and or in depth overhaul. The protective film doesn't last long. Since you are popping the front cover to replace the oil pump go ahead and take the oil pan off to inspect bearings. If there is damage it will be evident. For your sanity and the sake of your wallet I hope all is well.
"Beat it like a red-headed ford"
1987 v10 Silverado 4" RC, 35's, 700R-4, 3.73
2006 Boulevard M109R 109 cid, straight pipes, PCMlll,k&n
2009 Jeep XK, 2" lift springs in mail (future LS Swap)
GSXR 750 engine awaiting go kart

Offline LSXCHEVY

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Re: LQ4 OILING ISSUES
« Reply #3 on: May 13, 2015, 11:25:50 AM »
thanks froto for reply... I used the black o ring last time from what ive researched I think I need the thicker green one plus I bought a pick up tube o-ring girdle, uses both bolt holes, the engine is back from machine shop now, I was trying to post pics of the crank and bearings that got chewed up...there was shavings in the oil also but not sure if that came from oil pump or spun bearing or both!   let me see if I can get these pics up here...I saw a guy make his own oil primer but I feel confident in the lube during assembly.

Offline LSXCHEVY

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Re: LQ4 OILING ISSUES
« Reply #4 on: May 13, 2015, 11:45:31 AM »
the pics below are the #5 rod bearing, #5 crank journal, and 1st cam bearing...looks like lack of oil?.. about 3 more of the rod bearings turned also but this is the worst one.

Offline LSXCHEVY

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Re: LQ4 OILING ISSUES
« Reply #5 on: July 14, 2015, 06:05:23 PM »
Update on this ..new oil pump installed and good pressure around 60-70#cold.. the old o ring wasnot as thick as new one...original was green..melling had specific instructions for which one to use.. Made it simple...also realized that I was running way too much timing...motor might only like 28* total...idles around 23*..runs cooler too..

Offline frotosride

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Re: LQ4 OILING ISSUES
« Reply #6 on: July 17, 2015, 12:24:21 AM »
Sweet nothing like figuring things out. You will never make the same mistake. I'm putting off sticking my LQ4 in the 87 until I get relocated. But once I finish a 4 banger build for a guy at work the funding and possibly a new cam will be ready to start on the run stand.
"Beat it like a red-headed ford"
1987 v10 Silverado 4" RC, 35's, 700R-4, 3.73
2006 Boulevard M109R 109 cid, straight pipes, PCMlll,k&n
2009 Jeep XK, 2" lift springs in mail (future LS Swap)
GSXR 750 engine awaiting go kart