momentai91

Hey guys, okay before you go ahead and roll your eyes at me and say that's a rod knock there are other variables to take into factor. So I bought a beautiful 79 firebird from the original owner of 71 years of age. This car had some very absurd modifications that didn't make much sense. It has 2 electic fuel pumps fed into a mechanical pump on the block which ran to a fuel pressure regulator which just could not compensate and was reading over 40psi of fuel (the gauge's limit). So after loading it up and draining the oil it's obviously saturated with gas. So we replaced the fuel pump with a carter mechanical and the carb which was gunked up and only 2 squirters functioned (demon 800) with a holley 770 avenger. The motor makes power, it has NO metal shavings in the oil, it did however have visible sludge pouring out which just amazed me. It looked like it hadn't been changed in ten years. I have some clatter coming from the back right of the motor which i'm thinking may be the lifters but i'm interested to see if anyone has feedback. Otherwise the motor seems to run fine, it just has a bit of a shake and a "clacking" type sound if that makes sense but again NO metal shavings to be found. Timing is back to a safe point right now until I figure this out. I hear olds having oil circulation issues, a clog maybe?

What do you guys think?

tru-blue 442

Suggest pulling the valve covers and checking for plugged drain back holes on the ends of the heads to start with. Sludge is never a good thing. I thought the screami'n chickens that didn't have the crappy Poncho 301's were all Olds 403's from the factory?

oldcutlass

Welcome to the site, Olds engines really do not have oiling problems. Time to pull the valve covers and see where the offending noise is coming from. You may have lifter/cam issues.

momentai91

Thanks for the welcome guys.
It was pure black slime that we pulled out.It was probably only slime and sludge rather than sludge because of the amount of gas in it. I'm frantic this is a rod because I lost my 2j supra to a rod issue but it seems to run exactly the same even when I pull the plug wires so I ruled that out for the most part. I was thinking clogged lifters or a worn cam lobe? It has a mean sounding idle and i'm getting small amount of oil on blowby out of the exhaust (have to hold something over it to catch it) but it hasn't started in ten years previously so i'm guessing it's also pushing a lot of crud out of the motor. I'm afraid to try any aggressive treatments life b12chem or seafoam like I would in a newer motor. I plan on opening the valve covers next free day. I'm still learning olds motors so i'm hesistent to adjust the valves. it sounds like a very audible clack but there was no metal anywhere to be found to make me think rod issue.

tru-blue 442

Pulling the covers may tell a lot from a broken rocker bridge or even a rocker arm
or a possible bent push rod. Can you up load a video? I never could but maybe
you will have better luck. Olds valves are not adjustable FWIW.

momentai91

Bent push rod would be kind of nuts but maybe it would account for the shaking. Yes I can upload a video tomorrow When there's daylight. And for those asking this was a swapped motor by the womans son and was an original 301 car. Her son drove it in high school apparently. This was 20 years ago though.It runs fine though and I would think the shake was a motor mount of there wasn't that noise. I was checking the oil pan with the magnet and couldn't pick anything up and it also had a magnetic drain plug. I really would not look forward to another rebuild at this point.

tru-blue 442

It could be a stuck valve as well. When you pull the covers use a short piece
of wood, 2X4 or what have you against the stem an give each a rap or 2 with a hammer.

momentai91

I'll give it a shot. Gonna have to revise my original statement as well, very small fragments of metal, more than likely from normal wear in the oil pan. If any were more than 1mm i'd be surprised. Just need to state that. The magnet on the drain plug had nothing on it though.

How bad can a motor really shake from an issue like that? it's rev happy now with the holley but I haven't taken it for an actual drive yet. Are stuck valve and lifter issues common on olds? just seeing a lot of threads about them.

oldcutlass

Your making a lot of baseless assumptions. An broken engine mount will not cause it to shake. Olds valves are non adjustable stock. A magnet is not the best way of testing for metal, cut the oil filter open and inspect the pleats in the filter material. Since the engine is making noise, that most likely will be the reason its running poorly. Do some logical troubleshooting chase the noise first.

momentai91

I'll find it and cut it open today some time and post pics as well as a video of it running. if it's a rod i'd imagine i'd need to rebuild the motor

oldcutlass

Your imagination is correct, the lower end will need a rebuild.

Kennybill

Usually an extra fuel pump is for N.O.S. I may have missed it but I don't remember you saying anything about "oil pressure". Did you pull the plugs? X2 on cutting the oil filter open, Summit sell a oil filter opener. It could be a wipe camshaft.

momentai91

A few things before you click it. I did not realize my mic was covered for a period of time, I started it right where you can hear the noise clearly for about 5 seconds. Sorry about the alternator belt queel we haven't tightened it completely since replacing the fuel pump yesterday (need a pry bar to really get it tight again). The black soot coming out of the exhaust is NOT the same color as the oil in the engine. It did run insanely rich for a period of time but I'm not sure if that's stuff left in the exhaust or fresh. No visible exhaust fumes otherwise.

oldcutlass

I can't tell from that video whats going on. I hear all kinds on things. If you put it in gear and raise the engine rpm with brakes on do you get a distinct loud knock?

droldsmorland

Is it a 403 or a 455? What're the alphanumeric numbers behind the water pump?
As mentioned use your senses, mainly sight. Read the plugs, look at the oil filter media, look at the rocker movement at idle, observe hot oil pressure with a known good aftermarket gauge,(read no harborjunk). Perform a dry then wet compression check. Hopefully, you saved the old oil filter and you are not doing all of this TBL shooting with the old oil??? Listen to the exhaust, observe its color and odor. Does it smell like burnt oil, it should if you're seeing it at the tailpipes? Raw oil making its way all the way out to the tailpipes isn't good. That's bad oil control (rings, guides, seals). Any of the three could be fouling plugs. That could be the shake and knock your observing as your only running on 6 of 8 cylinders. Could be as simple as valve seals and an ignition tuneup and a timing adj.
And yes as Eric said, does it knock when you power brake? If yes it's rod knock.
By the way, a millimeter of metal in the bottom of the pan = a dead engine. How'd you measure this?

If all the above checks let us know. We'll guide you to the next step(s).

Recap, one step at a time:
1. plug read
2. Filter media read
3. Oil pressure read
4. Wet Dry compression check(keep track of all readings on each cylinder, dry test first).
5. Post the data

oldcutlass

The junk you saw on your hand from the exhaust is probably condensation and carbon that has built up in the exhaust.

momentai91

Okay where to begin....Well the black stuff is more than likely carbon like they stated. It's not what I just put into the oil with a fresh oil change. On that, no I am not running it with the old oil. I've never driven the car too far so I wouldn't know whether it power brakes. The furthest was the test drive when I bought it and it went fine.It however hadn't been started in years it seemed besides just checking that it would apparently and while the chassis is extremely clean I fear the engine was put away with no care at all. The oil was so gas ridden due to that fuel system that i'm thinking it may have fouled the plugs but pulling the plugs connection seems to make very little difference in engine noise. I would think a rod issue would smooth out if the cyl was pulled? Please correct me if i'm wrong there. How fast would a rich engine foul the plugs? and how can I test the compression? i'll grab a kit from amazon.

Edit: Oh and I was told it's a 455. I have a friend who's a mechanic who's been doing this with me and he told me to wait for him to crack the valve covers but I have replacements and gaskets for it. He installed the new holley for me and handled the bulk of things while I did the oil. I can also submit a pic of what the oil looked like if that would help. I filtered out the larger particles already so it's just goop and small bits of metal. I can upload it if anyone is interested. He personally doesn't think it's a rod but isn't sure but this is also his day job so he's giving me a hand when he cans.

Fun71

I read it as CHUNKS of metal in the pan, which sounds bad.

oldcutlass

Sometimes pulling a spark plug will quiet a rod knock. What he meant by power braking is what I described in post 14. Yes, an over abundance of fuel will foul the plugs quickly. At this point I don't think a compression test is necessary, pop the valve covers and check your rockers for tightness and see if they all move the same amount. If you had a lot of crud in the oil you may have some clogged and collapsed lifters. Also by removing the valve covers if you see a lot sludge buildup, be assured the lower end will probably be worse. Cut open and inspect the inside of your oil filter.

momentai91

Did this. Had the normal low sounding idle sound but sped up. Did not sound like when my 2j had a knock. revved it to about 3000 and then my brakes decided that they were done. They may need some work in the near future but it was sitting for years. I was very surprised and was dreading doing this test to be honest. I got a clunk from the suspension but that was about it.Reminds me of my low compression camaro lg4 with basically straight pipes chugging along in sound but not like a rod knock.

The timing is set back to "safe" levels at the moment. we're getting into it again saturday and changing the plugs. Have a compression tester on it's way from amazon just to be safe. I feel like under those valve covers is going to be nothing but sludge and carbon buildup.

Wait wouldn't this just be the burnout test? lol

matt69olds

The chunks from the oil pan may well be from the nylon timing gears. Put a mechanical gauge on it, make sure the oil pressure is good. The sludge is probably stuff all the gas in the oil softened up and broke loose. Plan on changing the filter a few times assuming you get the other issues resolved. Check the plugs, rockers, pushrods, valve springs, etc. Any of those can cause no is and rough idle.

momentai91

We bought 2 kinds of oil, one cheaper kind to run the first time and then drain again and another filter so i'm definitely on top of that. I'm thinking the plugs may be fouled by how insanely rich it ran (pretty sure I could run a car in the oil that came out of it). It wasn't long but it could be enough to do it. I just want it drive able, I don't care about a little noise but I just need to make sure it isn't anything more serious.

oldcutlass

If it did not sound like someone was banging on the engine with a hammer with the noise increasing with rpm during your power braking test its not a rod. Chances are its all valve train related. You'll know when you pull the valve covers.

tru-blue 442

Just a thought but you might check and see if the torque converter bolts are tight
to the flex plate. If loose they can make a clunking like we are hearing.

momentai91

Going to try it again tomorrow just to verify as it gets very loud within the vehicle but i'm fairly certain it didn't sound any worse. I'll record it this time.

momentai91

So it was the plugs making it shake so bad. As soon as I checked them they had fouled and it was missing. However the "clacking" has not totally gone away and after pulling the valve covers see that the rocker area had some play on both sides. It runs fine for the most part (still need to advance timing,tune, detent cable and some small stuff) but it's obviously not being driven around yet.It went down the street and back today when we put wheels on it but that's been the most it's been driven. I have a holley avenger 770 on it and i'm hoping that is enough for it. Cam seems like an RV cam, anyone else end up with play under the valve covers but it generally seems to run/rev fine?

oldcutlass

Drain a qt of oil and add 1 qt of Rislone engine treatment. Drive for 1-200 miles to see if noise goes away and change oil.

momentai91

A buddy of mine suggested running rotella for an oil change. Any input on that? noticed mondello mention it as well in a video but said they didn't want to run it long due to sludging.


I'll pick up some Rislone.

oldcutlass

Rotella is just a diesel oil and won't do what your friend suggests. A lot of people run it regularly in their cars, but thats another discussion in itself. You can also run a qt of transmission fluid in your oil it will do the same thing as the Rislone.

With your valve covers off, disconnect the coil wire or unplug the HEI if applicable and hand turn the engine to each cylinder so that the valves are closed. Pulling all the spark plugs makes rotating easier. Move the push rod up and down and see if there is play. There should be no up and down play in any of them. Oldsmobiles have non adjustable rockers so any play leads to tapping noises.

Kennybill

Did you put a name brand mechanical oil pressure gauge on and if you did how was the oil pressure?

momentai91

They did in fact have some play when pushed down which seems to lead to the clatter (around rocker arms specifically). It has quieted some since it smoothed out when the plugs are changed but it almost seems like oil wasn't flowing up well if that makes sense.

Also no we didn't get a new one in yet. After cleaning up some wires for the newer battery terminals some things need hooked back up. The one in it was some junk one. It idles just fine and actually broke traction with little effort while taking it down the street for the wheels. We were looking at lifter/cam/AIO kits just in case I do need to replace anything.

Kennybill

I don't want to be a bad person but the most important "tool" one can have is a good mechanical oil pressure gauge. Pipe it into the block where the oil sending unit should be. The factory timing nylon coated sprocket are famous for deteriorating sending chunks of nylon into the oil pan and getting sucked into the oil pump screen. Once plugged little to no oil will be pumped. A sign of low oil pressure is collapsed lifters. As I said in a previous thread, I would not have started the engine until it had a mechanical oil pressure gauge. I still think that.

oldcutlass

An inexpensive mechanical oil pressure gauge as suggested is a good idea. Engines producing very low oil pressure is an indication of other issues also.

momentai91

I'll pick one up. Again this car sat for many years (15 or so) before I started into it. I'm amazed it's capable of running like this at all. There's a broken one in the car with a little oil in the line but it doesn't seem to feed in at all. i'll replace the line and gauge

momentai91

So the vehicle runs but it's got blow by in the left exhaust pipe and the mechanical oil pressure gauge doesn't seem to be working but I think it's due to a lack of oil pressure. Definitely sounds like the top end is starving. Is there any other port I can try for oil pressure?

oldcutlass

The one above the water pump on the left flat area of the block.

momentai91

Mine is plugged almost directly center below the intake manifold on the flat portion. Is that normal?
Any pics that might help? sorry for playing twenty questions guys. No oil pressure up top is making me panic a little bit. Would explain the lifter issue as well due to starving out.

oldcutlass

There is only 1 place you can use, you may as you said earlier in the thread have a bad gauge.

droldsmorland

That shelf contains the engine identification number.

Lets stop chasing our tails. That port is part of the internal oiling system circuit for the whole engine. If there is not any oil coming out of that port you have an engine that is dead or close to blowing up. Pull what ever is plumbed into that port. Leave it open and crank the engine for 30 seconds, isolate the ignition system you dont want it to run. Oil should shoot out not dribble out? No oil = Dead oil pump, dead engine.

oldcutlass

That'll work, however if there is oil pressure it will get messy.