03 Z06 lost oil pressure / missing
07-08-2012, 10:10 PM
#1
TECH Resident
Thread Starter
iTrader: (10)
Join Date: Oct 2005
Location: Cincinnati, Ohio
Posts: 948
Likes: 0
Received 0 Likes
on
0 Posts
03 Z06 lost oil pressure / missing I just got this Z06 I bought running today. It sat with a blown engine for 2 years. It dropped a intake valve at 44K miles. I bought a LS6 short block and another set of 243 heads and out her back together again all stock. I used the cam and lifters and kept their proper order. I transferred the oil pump and tube, pan, everything else. I pre lubed the engine with a home made oil tank. The car fired up like I just shut it off. It had 40psi at idle cold and would slowly climb to 60 as you gave it gas. Everything seemed fine. I drove it up the road and back with the old gas (yeah I know) but drove it very easy. I put maybe 10 miles on it just driving easy. I came home and pushed the clutch in revved to say 4000 and it died. I started it up but it was making some noise that sounded like lifters. I pulled the valve covers and checked everything. All springs good, all rockers tight. I pushed down on the #7 intake rocker and it felt soft. I started it again and pulled injector plugs and isolated the dead cylinders all 4 of them. 3,7,2,4. At this point it still had 40 psi at idle. The more I messed with it trying to figure it out the lower it got. I have 10w30 mobil one in it. I am at a loss, I have busted my *** the last 2 days getting this thing back together. Did I spin a cam bearing? Did I dick up the oil pump oring? I installed the pickup tube straight in while the engine was upside down. I hate to yank the engine but I will if I have to. Sorry for the novel but if you guys have any thoughts I would appreciate it. THanks
Dave
Dave
07-09-2012, 05:41 AM
#3
TECH Resident
Thread Starter
iTrader: (10)
Join Date: Oct 2005
Location: Cincinnati, Ohio
Posts: 948
Likes: 0
Received 0 Likes
on
0 Posts
Engine was not blown, dropped a valve at idle and broke piston and block. Engine shut off and stuck at that moment, no water went through pump. No bearing damage or lack of oiling. I can't see how that would affect the oil pump.
07-09-2012, 08:17 AM
#4
TECH Resident
iTrader: (2)
Join Date: Sep 2010
Location: Salisbury, NC
Posts: 909
Likes: 0
Received 0 Likes
on
0 Posts
Idk how long it ran but if you drop all the parts and pieces into the oil pan when you punch a hole in the piston and let the pump suck it up not only will it hurt the pump but you'll then pump metal through the next engine the pumps on. Im not there so I don't know the case but that is where I would look first
07-09-2012, 09:11 AM
#5
TECH Resident
Thread Starter
iTrader: (10)
Join Date: Oct 2005
Location: Cincinnati, Ohio
Posts: 948
Likes: 0
Received 0 Likes
on
0 Posts
When valve dropped it locked engine since it was at idle. Piston did not shatter only had dents. Cylinder wall was broken and pieces were in cylinder. Unless the pump had a internal failure or o ring blew out or something what could it be? Lets say for a minute i used a brand new pump and not a perfectly good used one, what now?
07-09-2012, 10:49 AM
#6
TECH Resident
iTrader: (2)
Join Date: Sep 2010
Location: Salisbury, NC
Posts: 909
Likes: 0
Received 0 Likes
on
0 Posts
well whats bothering me is that it slowly got worse and worse. I suppose its possible that the oring got sucked up and slowly caused the problem. I guess i would start there but if not you may have spun a cam bearing or something. Someone else chime in though this is all speculative of course
Trending Topics
07-11-2012, 06:25 PM
#9
TECH Resident
Thread Starter
iTrader: (10)
Join Date: Oct 2005
Location: Cincinnati, Ohio
Posts: 948
Likes: 0
Received 0 Likes
on
0 Posts
UPDATE: I have some ketchup so I can eat my words. The oil pump from the original engine had a stuck bypass valve. It took about 1 1/2 hours to get the steering rack out and pull the water pump, cover and balancer. I pulled the pump off and disassembled it. Everything looked okay until I tried to take the bypass valve. It did not slide out easily like the other one. When I finally did get it out it felt rough and I imagine the inside of it's bore was chewed up too. The pump gears looked great. I started the car with a new pump and the oil pressure jumped to 50 at idle so I shut her down so I can put it back together. Live and learn.
