Durango_Boy

Fram is crap. They have the cool grippy stuff on them, but they can't filter clean water...

Wix is one of the best I have found.

Lilysdreamvette

New cam bearings were used both times. I know enough to line them up when installing them so I'm sure they were lined up the first time.

I have been using the Fram filters since the beginning and will take your advice and switch. I recently saw a cutaway of the major brands and Fram did look the worst. Bosch looked the best out of the three that they cut apart. I do like the Fram HP-1 filter though.

With the block possible being cracked, I fear the only way to tell would be to dissassemble the whole thing and Magnaflux, right?

Thanks for the ideas and keep them coming.
Greg.

TERRY CLARK

Maybe a bad oil pressure gauge !

bashcraft

TERRY CLARK

Is the pressure low at just idle or always? Normal is 40 PSI @ 2000 RPM for Chevys. How much assembly lube did you use. I have heard of people using too much and clogging oil passages !

Durango_Boy

You're saying too much oil pressure will cause a clog? What's the logic there?

Twin_Turbo

too much assy lube or moly grease

Durango_Boy

That I agree with, but even still it would dissolve in the hot oil wouldn't it?

turtlevette

Most things i've read say replace the oil and filter after about 30 min because the grease plugs it up.

Hard to belive it could be this simple but it might be.

Lilysdreamvette

Thanks for the replies again - I dump the oil and filter immediately after break - in of the cam on all the motors that I ever built. Then again after a few hundred miles and then regular intervals. This one didn't even have 20 miles on it both times it was rebuilt. The moly lube was used but not excessively and I used the same procedure with this motor as with all the others.

The oil pressure, if yu can call it that, is very very low (I won't see how low actually because I shut it down after it falls to 7-8). Add a little speed to the motor and like I said it only goes up to maybe 20, if that.

Thanks,
Greg.

TERRY CLARK

No, I'm not saying to much oil pressure will cause a clog.....With a new rebuilt engine oil pressure should be even above 40PSI with a stock oil pump. Are you running a high pressure or high volume oil pump? You should run stock or high volume but not high pressure, high pressure could pump the pan dry. Your machine shop should know if something is missing from the block causing the loss of oil pressure. Could be a bad oil pump!

Durango_Boy

I would think, if the pan were sucked dry, a good portion of the oil would have to have been sent up to the heads via the push rod. If they are not getting oil, and the pan is dry...where isle is it going if not that high?

...Roger...

Greg is this a made up story ???

TERRY CLARK

A rebuilt engine if it was done right should have some serious oil pressure....somebody has left out a step. or somethig is clogged or bad oil pump !

Lilysdreamvette

Dwncchs,

With all due respect, I don't have time to sit here and make up phony stories for no reason. I am restoring a 71 Cuda, rebuilding and reinstalling a TKO600 tranny for my 68 Charger, trying to get a 66 Dodge polara 4 door driveable, sorting out electrical problems with my daily driver 92 dodge stealth, completing some house projects and working full time (in addition to sorting out this 69 vette issue). You get the picture.

How and why on earth would I want to waste time on ficticious stories is beyond me.

This is a real and true mystery to me and that is why I came here to seek help from corvette enthusiasts alike.

Greg.

...Roger...

Sorry Greg didnt mean to offend.I have a few questions in the pursuit of trying to solve this problem.Please bear with me and not take offense to my odd questions.I really am trying to sort out your problem and partially by sparking new questions and ideas from other more knowledgable members.

Obviously as you have said you have done a lot of engine work.I'm a little surprised you gave up and took it to a builder and replaced 100% of all the new parts that you just put in 20 miles ago.That was expensive,how much did that cost?

Magnaflux....Cheap....I would have thought that would have been tops on your list given your problem.From your posts your no dummy,you know a lot about an engine.
I think it is unlikely that a seasoned block would crack in the oil passages when its initial problem was a worn cam lobe unless it was severely overheated and you didnt mention that.

You said 2 of the bearings were wiped....."WHY" would you tear into it after you just paid a builder to do the complete engine ???I would have had that back in his shop the next day.
You also said you never let the oil pressure dip below 8lbs.In my opinion these would not be wiped due to low oil pressure because the pressure was never below 8lbs.Could you send some pics of the 2 wiped bearings and rest of the bottom end please? A couple pics of the engine compartment and the car would be nice also...we love pictures !!!
Being that the bottom end is open did you recheck the plug that 427hotrod refered to?I ask if the distributor had been changed,it is also part of the oil passages.I have see some of the old big block dist.that didnt have the lower groove ground all the way around screwed up by someone trying regroove.When they do this they go too deep and then some of the oil gets dumped back into the engine causing low oil pressure.
I hope my questions dont upset you and if they do remember they are "mine" not the other members.This IS a great forum and there are only a couple of a$$holes like me in it.

Durango_Boy

In regards to the bold print...don't EVER say that again. I know you're kidding, but there really are a few bad apples here, and I don't like the thought of you lumping yourself in with them.

...Roger...

Thanks Durango--That A$$hole catagory is pretty big and there is plenty of room in there for me. I fit in the "****" section and some of the forum members have told me so. Thats OK I'm fine with it,even my customers have told me I'm **** and then they go on to say and thats why "you" get to work on my car.
(Its only when I break that bolt off "being" **** that it pi$$es me off)

Lilysdreamvette

DWncchs: I understand. No offense taken. It's just that sometimes some members are so quick to jump down someones throat, that's all.

Thanks for trying to help me resolve this issue. Let me back up nearly to the beginning. This motor build has been going on for almost four years now due to all of my projects. I have to think hard to remember the correct order of events. I'll quickly recap and add details for what you asked me:

1)Bought Corvette in 2002. Car didn't run.
2)Checked it out and noticed fuel supply line hooked up to PCV port on carb and PCV line hooked up to fuel inlet on carb (Edelbrock 600cfm)
3) I switched the lines and pulled the spark plugs out and fuel just pured out of the cylinders.
4) Let them drain and dried them out with compressed air and oiled them up.
5) new plugs and the car fired right up.
6) Car had numerous gasket leaks on engine.
7) pulled out to change gasket and after manifold off, noticed (1) wiped cam lobe.
8) Realizing metal fragments circulated throughout engine, planned (low budget) rebuild.
9) Dissassembled engine and thoroughly cleaned block after:
only honing cylinders myself, New rings, same pistons, same rods untouched, new main/connecting/camshaft bearings installed,new freezout plugs, installed cam bearings in proper orientation in block (I have the install tool)
10) Cylinder heads were completely rebuilt with all new quality parts: new SS valves, new comp cams springs that cam with cam, new stampled steel roller rockers, new screw in studs installed (ARP), 3 angle valve job performed and I confirmed seating by hand lapping.
11) I assembled engine components using fel pro gaskets throughout and DID NOT verify clearances because rods and crank was not machined.
12) New Edelbrock Perfromer manifold and New Holley 750 Vac sec carb installed.
13) New Melling Standard oil pump and pickup used as well as new ARP hardened oil pump drive shaft***
14) Oil pan thoroughly cleaned out and degreased and reinstalled.
15 )Broke the cam in and all was well for a few weeks.
16) Noticed when engine warmed up oil pressure would drop excessively.


17) Dropped pan and few main and connecting caps - bearings down to copper!
18) Removed engine again and due to too many projects, brought to professional machine shop/engine builder for SHORTBLOCK REBUILD ONLY. Cylinder heads were freshly done prior.
19) Block was tanked, align honed, bored w/ plate, honed, decked, new freeze plugs, new Sealed Power pistons, moly rings, conn. rods caps cut and resized, crank cut .010/.010 and polished, new cloyes roller timing chain, comp cam magnum 280 cleaned and reinstalled.
20) static comp. designed: 9.5:1
21) Assembled top of motor and oil pan and installed in vette.
22) primed pump using drill and purchased priming tool and confirmed oil at both sides of rockers. All is good.




23) Same story as first time around. Good oil pressure for a little while (a week maybe - Total run time maybe 2-3 hours) and them lose oil pressure when getting up to temp.


*** The only thing I noticed when installing the new oil pump and drive shaft was that there was about 1/4" movement up and down at the shaft between the distributor drive and the oil pump. Has anyone noticed this and/or is this normal. with the shaft up all the way or down all the way, the oil pump drive is still engaged and therefore turning, but this doesn't seem right to me. I no longer have the orig. one to compare lengths to.

I could swear that I recall reading once that there is a short and a long oil pump drive shaft for the Small Block Chevy. Does anyone know of this? I don't even know if this presents a problem.

That's about it. I pulled off the caps again to find the same situation: Bearings down to the copper and scoured.

I will try to get some pictures of the car/engine comp posted soon. The bearings are going to be tough, because the pan is back up and the car has to be moved for me to get under it. I'll try though.


Thanks again for any help. I hope this information helps any diagnosis.

C64BOB

If this plug is not there the oil pressure decreases with load (like when you stuff your foot in). Then you start wiping out the bearings due to low oil pressure. Now you've got crap in the oil and it's not being filtered. Things go bad in a hurry.