Oil pan!

[SunlitComet]

well the pm does not work yet either it looks like. there were three plastic parts related the oil pump i believe shaft bushing, shaft guide and shaft retainer. cylinder head drain holes are not that big and i dont think the cylinder block drains were either. have not taken out the oil pump before but here is a breakdown of the lower block for the most parts.

and those are quick disconnect lines on the oil adapter.

if you lost oil pressure suddenly i would not propose reusing that pump and it is likely the the press in pick up assembly may not really stay press in any more after tearing it down. you can get a new pump or a repair kit for it. as for the sludge being there. clean it out of course but i think i would be careful and put a new complete one in there withe a new pick up part as well. both should cost under $50 for melling parts.



cant think of anything right away of where else that plastic part would come from.

 

[HardKnox]

I remember the size of the drain holes in the valley under the intake and it would be a very tight fit for that black part to have made it through. I see your point on that.

I'm replacing the pump and took apart the old one. Thank you for that link to the spec/parts sheet. Will take a closer look and compare to what was removed but kind of looks something like the part #415 Think this is the pressure regulator valve. I did pull the spring from the old pump after drifting out the pin. There is for sure one more part inside, but did not remove it yet. By the pic it looks as if there should be two.

Other than the black part (smaller inner diameter than the pump shaft) the only other plastic part so far is the retainer/bushing that joins the pump shaft to the pump. Is there a legend of any kind for that break down of parts on the spec sheet?

Still have yet to come up with good instructions for the quick release lines on the adapter. I know this type of plastic is/can be very britle. I have not tried anything yet that would break them. Will see if they can be replaced easy and if so pick them up if possible.

My oil pressure went out like this... Pressure fell to near zero at idle speed...At about 1500 rpm it would raise to about 40.... This lasted a very short time however. (maybe a mile total) When the pressure fell to 20 at higher rpm I did smell the oil. As quickly as possible I turned off the motor and coasted to a stop. Did not attempt to start the motor again.

Thanks again Be back later

edit; just checked those pdf's Very, Very helpfull Thank you

 

[SunlitComet]

this is for a 1996 chevy tahoe 4wd with 350 vortec and 4l60e tranny. you can go to the home page and input your vin so the database will filter out the unnecessary listings.

http://www.gmpartsgiant.com/Page_Pr...4WD&RPO=X88&eCode=L31&tCode=M30&mCode=CK10706

no signs of external leaks i suppose or in the tailpipe? check you galley plugs as well and the pressure switch in back of engine to the left of the dizzy. you said you did the lifters and rockers just before correct? and when pressure was lost any difference in engine running? cylinder drop offs and such?

 

[HardKnox]

Thank you for the link. Havent checked it yet but everything else you have pointed me to has been of great help.

Yes, I did replace lifters, push rods and rockers. Long story as to what led up to that project but suffice to say I knew the tapping I was hearing was located in the valve train. Did not know for sure when I tore into it but knew what ever it was wasnt going to fix it self.

What I found was worn push rod ends ( 8 to be exact ) It varied and some were exhaust, some intake, several cylinders. The scoring was pretty severe on a few. I had allready purchased the lifters and intended going that deep regardless. I did not find any lifters that appeared to be damaged and all had operable and smooth rollers.

I did find a leak in the exhaust manifold. There was a build up of oily but wet sludge.

At the time of that project I also replaced rotar, cap, wires and plugs. New oil filter and a total of 2 complete oil changes. Dumped the first oil and filter at 300 miles. Only a small sign of leak but appeared not to be in any area I had recently worked. Old slow leak. Think I found the source of it tonight actually. Oil pan gasket just beneath the timing chain cover. Not large mind you, just a lot of blow back over time.

When the pressure fell the motor wasnt missing a beat. It has been running strong allthough a noticable stutter under power occasionlly. Not constant, but it was becoming more frequent, and the morning of the oil pressure loss was notably more. At power doing 60mph it felt almost like a soft bump, but clearly was from the motor. No noise with the stutter.

I'm going to clean and go over everything I can think of. You say galley plugs? I'm not sure what that/those are. Will probably replace the pressure switch as well while I'm at it.

Compression check and timing where done at a reputable local shop. This was done after my lifter : slash : tuneup job. Ran good other than the stutter and then the loss of oil pressure.

As for the mystery black part in the pan. After looking at the pump ( old one ) which I took apart, it does not appear to be from the pump itself. All parts are acounted for and the demensions of the part are to large, or small. Still scratching my head on this one...

Back to it tomorrow after work. Still havent figured out those disconnect lines but havent had much of a chance yet to look at them again.

Thanks again

 

[SunlitComet]

i would give your valves a good wiggle to make sure they are not loose. grab them at the top off the valve assembly. since you did the lifters and found the worn valve train parts i would like you to consider that, with your finding in there and in the oil pan, that maybe some of the sludge had begun to block passages and stripping the lubricity of some parts. when you get it back up and running and perhaps later inspect to see if the problem redevelop that you may not have a choice to tear it down and clean it out. when the blocks are made all the oil passages are drilled. most will meet a moving bearing and such to they will flow appropriately. however the main feed passages in the blocks need to have plugs in then oil the oil will go right out the block. you will find a 1or 2 of them around the bottom of the block. if you decide to deal with the timing cover leak you need to get a new cover. you can not reuse it once it is removed. if you have the tools and time and since the oil pan is out it would not hurt to button of as many leaks as you can. btw what brand and part #'s of ignition parts did you use?