Sorry for re-post, bad topic on previous.
Salute fellow 3rd gen'ers. 87 IROC-z 5speed with oil cooler, she has 160k miles has been daily driver for 6 years. The oil gauge has always been near 60lbs of oil regardless of accuracy it had oil pressure. My problem now is poor oil pressure. Im stuck at clearance problems for the oil pan removal. I hope this information is enough to get a good reply/and or help future readers. Im all ears to possible solutions for poor oil pressure.

The car is set to 1250-1500rpms on cold start and 500 idle. Now when the car does a cold start I have a slight knock; I even pre lubed the engine by bumping the starter. When its a warm start, it doesnt knock noticeably. Sometimes while taking off from a stop, if I baby it, she knocks a little not extremely loud but somewhat noticeable.

Whats weird is the oil pressure on cold start is normal, but on warm/hot start the oil pressure is the same as if Im driving. I get 15-20lbs of oil while driving, at stop lights 0lbs of oil according to the gauge, and 15lbs of oil if I slightly increase the rpms at stop lights.

I drove out of state and when I went to leave the first of 2 stores in a small mini mall, definitely on first hot startup it had a valve tap for 1-2 seconds. Havent heard it since. I believe because the engine is not sufficiently being supplied with oil, the oil pickup line/screen could be clogged? Im trying to get the pan off, the back of the oil pan just barely cleared the bell housing of transmission to pull out but is being hung on what my dad says the front main bearing cap, but I believe I seen its being held on the crank.

Im not a certified mechanic, but have always worked on my own %&^$, including my old 86 lg4 sport coupe. My father is well knowledged with cars. I have been reading many posts about removing oil the pan/knocking problems and Im currently stuck trying to get the little extra clearance to pull the oil pan. The motor is jacked little over 3 inches (eye to eye) in-between motor mount brackets

I just rebuilt the top end last winter; the intake gasket was letting anti freeze in the oil. So Im pretty dang sure the top end/valves are not the problem. Had a valve job done with new guides, new seals, and new seats. Also put new rocker arms and nuts. When the motor was apart there was glycol (mayonnaise substance) all under and in valves; which was cleaned out, except the oil pan. It never struck my mind. After the rebuild we did put 4 quarts of oil and 1 transmission fluid to ensure the system was clean. Changed oil after test drive.

I dont have an engine hoist so I compromised and made a makeshift lift. I have the chain hook on the lower front side alternator bracket and for balance also bolted on to the a/c bracket on top. Chain then lifted by a come-along attached to a long 4x4 piece of wood hung in loops of 2 straps. The other end of straps tied to a 2x4 piece of wood across 3 beams of the garage's roof (if you have use a 4x4 too, for extra beam support), which works well.

I loosened motor mounts, removed oil filter, starter, distributor cap and rotor, dust cover for flywheel, y pipe too since it was loose at cat anyway, the transmission mount nut is loose, put motor at Top Dead Center and spun the motor 1 revolution on timing putting me at 180 degrees (or 6 o'clock), and tried jacking the transmission a little, AFTER I maxed out my *** along lift AND bottle jack started raising the car. My engine has a factory oil cooler so I loosened it looking for clearance/wiggle room to of no help.

I jacked all I could its now lifting car so transmission is probably maxed not motor. Here I am for advice hoping someone can fill in the missing link I need for clearance.

Any help or shared knowledge is appreciated. Ill be checking back to keep up with replies.

p.s. worst case scenario ill loosen transmission bolts so motor can be pulled to front of car for my clearance, but Ive read you dont have to.

 

i did the work yesterday. in my 85 with manual trans. unbolt your eng mounts, jack up enough to fit a short 2X4 between each eng mount(you will need to jack higher, but its a safety measure). now remove your distributor cap, rotate your balancer so that the notch is at 6o'clock. continue to jack until you gain enough clearance to slide the pan out. you should actually gain plenty of clearance. good luck!

 

roger, yes distrib is off, starter, oil filter, ypipe is off, crank is spun once from TDC(have to make sure its 6oclock), motor mounts seperated with right now 3 inches inbetween (going outside now to shoot for another 1/2 inch read somewhere guys said 3.5 inches)

i even took off nut to hold oil cooler sandwich block on, didnt help. i also have nut loosened on transmission mount, its so close im just afraid of pulling something. ive checked over and over before i jack but im nervous and seeking tricks of the trade.

p.s. vasq, nice car

 

just watch while your hacking, mine appeared to be lifting the car a bit, but you can gain the clearance, to go straight back and down. i didnt take my filter off. but the starter was off for different reasons.

 

ok my *** along was maxed, so i bottle jacked from under now its jacking car slightly. last night i got 3 1/8" clearance eye to eye in mounter mount brackets. today i couldnt achieve 3 because i believe the driver side engine may be cocking bc of bottle jack. im just going to have to loosen the transmission i guess. im still all ears if im missing something.

also someone feel free to introduce other explainations as to why im not getting sufficient oil pressure. i understand the oil pump almost never fails but i may replace anyway. im trying to get the pan off to look at the pickup line, but is there any other reasons why i could be getting the knocking and/or explain why i had the temporary valve tap on one hot start after my trip?

 

I can understand the nervous part of this project, after checking the oil pickup if it was my car I would check the rod and main bearings.

 

Update: I got the oil pan off without using my bottlejack. I had the counterweight for the crank was spun 360 instead of 180 from TDC. Even when I did spin 180 from TDC, i was a few degrees off causing the 2nd counterweight on crank from front of motor to slightly hang up the pan. My dad stuck a prybar inbetween the motor mount brackets driver side and applied pressure, clearing the 2nd counterweight and the pan slipped right out. Once the pan was off I could see these counterweights were the problem the whole time.

By spinning the harmonic balancer once, it puts the motor at 360 out of 720 even tho the engine is a 4 stroke, the harmonic balancer only spins twice per engine loop. So the correct way is to spin the harm bal 1/2 rotation. So that explains why my counterweights werent lined up. I backed up the harm. balancer 90degrees counter clockwise moving me from 360 to the desired 180 from TDC. So from TDC the harmonic balancer needs to be spun 1/2 revolution.

Point being, transmission does not need to come off on my 87 iroc-z. Also, no metal shavings in oil pan nor the oil filter. Connecting rods appear to be in good shape. Oil screen has a small chunk in it. Ill post more updates.

When the pan did come off, I was so excited seeing/invisioning it come off I kinda dropped the pan and chipped my front tooth. lol

 

How long did it end up taking you to pull the pan? I'm thinking about dropping the pan in my 89 Iroc. Its got a slight leak at the back of the pan and I'm going to replace the oil pump and pick up while I'm in there. It only keeps about 10 to 15 psi hot idle in gear.

 

well for other reasons, my car has been sitting in the garage for 3 weeks. Apparently, if you read around its a 3 hour job. If you read my topic thoroughly, I share methods to do it without dropping the trans.
#1 make sure the counterweights on crank are out of the way by setting motor to top dead center and spinning harm. Balancer 1/2 turn clockwise, putting you at 180 degrees, it will set the 2 counter weights on front side of the crank out of the way for the oil pan to slide out. When the oil pan is loose you can see in, the counterweights are a 1/2 circle. This was the problem for me, I accidently spun to 360 degrees putting these weights in the way for clearance. You can see if theyre in the way. Just be sure, where, the motor is set to.

 

My 87RS with the 2.8L V6 had the same problem. Good oil pressure when cold, 0psi hot and 30psi above 1500RPM. I did replace the oil pump and didn't help. The problem is excessive bearing clearances. When the engine is cold the oil is thicker and takes up the clearance so it has oil pressure. When the oil warms up it thins out and the pressure drops due to the excessive clearance. If you're going to change the pump use the Melling M-55A high pressure pump it gives about 10-15 psi more than a stock pump. High volume pumps don't give higher oil pressure at idle but above 1500 RPM they flow more than stock for enlarged oil passages and added things like oil coolers and remote oil filters. Basically the bearings are worn and its time to freshen up the engine.

 

The bottom end rotates once per balancer rotation. The four-stroke aspect ONLY affects the camshaft and the valvetrain, ie the top end of the engine. If you turn the balancer a full revolution, the crankshaft counterweights are going to be in the exact same spot as before.

Sucks about your tooth, sounds like something I would do. Also, it's very common for a piece of the oil pump driveshaft to come off in a big chunk and end up in the oil pan somewhere for decades. I dont remember exactly what this piece is but I learned it from some of my research material back in the day. It's some kind of unnecessary collar/sleeve thing on the shaft itself, and it's notorious for falling apart early on, and it isnt a big deal. Might as well get it out while you can but if that's what it is, dont worry about it. Other possibilities are that it's some part of a valve seal or valve spring.

 

On a cold start my car will go to 50 or 55. If you bump the throttle slightly it'll peg the gauge on cold start. 15 to 20 minutes of driving I can keep 45 ish and it slowly drops to around 35 driving. I hold 10 to 15 hot idle in gear. Let us know if the pump fixes it. I'm hoping mines just got a piece of a carbon patty in the pick up.

 

I vouche to this. My father was trying to tell me thats why on hot-hot startup after my out of state visit to a store, additional to my knocking, I had a mean valve tap roughly 1 second on start. He said the lifter started collapsing, I felt it was just poor oil pressure and something was getting starved. This was the only valve tap Ive heard from any of my 3rd gens. This proves your theory, which is pretty logical.

First, thanks. Negative on valve train, I had a full valve job done by a reputable machine shop in december 2010, when the intake gasket went(lots of "mayonaise" in topend).
Yeah my friend already got me the high volume mellins pump. Ive read, AND he specificaly told me about the nylon collar piece you speak of, my pump comes with a metal one, so, done. Ill let you know the condition of the nylon piece; engine at 160,000 miles.

Was going to install oil pump, but with taken advice from 3rd geners and friends, decided to order main and rod bearings.

So decided to stay busy and install new rubber hoses on my oil cooler. Drained the radiator lines from the radiator to the oil cooler, and noticed oil globs in the anti freeze, some big ones. Also, there were traces of antifreeze in my engine oil I drained initialy, so obviously my oil cooler is failing, pictures below. Now I need an oil cooler, I know the minute significance but it came with the car and will stay.

P.S. dentist fixed my tooth, cant be having that in new jerzy d:]

 

pictures off my HTC evo cellphone
our engine hoist







my oil cooler cracks

 

i have a 91 auto tpi, and i cant get the oil pan out as well...ive removed the distributor cap and rotor, engine mount through bolts, starter, exhaust from the headers, the timing mark on the crank is at 6 o clock and ive maxed out on how high i can lift the engine, the flexplate seems to be in my way and ideas on how i can get this thing out?

 

if the timing isnt right what happens is when you pull the rear of oil pan down, the pan gets hung on the crossmember, and the front of the pan hits the engine. the only way the pan can pull out is if the crank is correctly positioned so the front of the pan is not hung up when you slide it out. so you can "see" the clearance inbetween the oil pan and the gasket surface when it can slide out.

its gotta be the crank counterweights in the way. when mine came off, if you move the pan the right way you can see it has room to come out. when you see the clearance inbetween oil pan and motor dont get too excited, i rushed the pan out and hit my tooth lol. try having someone pry the driver side motor mount open more, its how mine slid out. eye to eye on the motor mounts i had 3"+

 

After 168K it's time for a full rebuild.


Once you touched the top end that was the clue of "good things" to come.


Better off to do a full re-build, otherwise you will be constantly changing parts.

with the oil pan off you can replace the oil pump and possibly the main bearings.. but the stock k-member is a PIA. easier to pull the engine out.

what about the small end rod bearings. cam bearings, piston rings, etc, etc?

the motor simply will not run forever.. it sounds like it is due for a complete overhaul.


You can rent a cherry picker.. etc etc.. try to find a reputable engine shop and get a quote to rebuild your engine.. it can be rebuilt stock if you are happy with that or start looking at crate engines you can buy online.