I pulled my valve cover to investigate some tapping, but it's a real mess on there, big flakes of crud sitting at the bottom and caked on sludge on the valvetrain. Should I just tale care of the big pieces, or tale care of the whole thing, and what's the best way? Wire brush and compressed air? I don't want to pour chemistry in there and have it end up in my sump, but I also want to make sure the oil returns are clean... Speaking of which where are they?

 

Rebuild the engine.

 

The oil returns are at the front and back of the head. About 1/2" wide near the bottom.

If it were me I'd Drain the oil, and save it in a jug.
Leave the drain plug out, grab a case of Brakekleen, a bag o rags, and the shop vac.

Vacuum out the oil drainbacks first, and clean em up. then block them off with a piece of rubber hose before tackling the rest of the mess. that way the biggest chunks that will make it to the sump, will have traveled via the pushrod holes.

Nilsson is correct. The engine has had a rough life with cheap oil, and this cleaning is only a crutch.

 

I have plans for that soon as my budget allows, I just want to clean it up for the few miles I'll drive it til then

 

Using the shop vac on the oil drain holes is a good idea, because the oil holes dump into the valley. Crud going down thru the holes could end up on the cam, and has to pass thru the crank/rod area before it hits the sump.

But don't vacuum any brake clean or other flamables, it could explode.

Note that the drain holes have a sharp bend in them, and they neck down to 5/16" at the bend, so you need something flexible to push through them for your final cleaning.

 

I was gonna rig up some .25" vacuum line to my shop vac and get in there, cap off the drains and blow the rest out, then change the oil, sounds good right? Hah bikes I know, cars are something kinda new for me

 

This is like putting a Band-Aid on a gunshot wound. My suggestion would be to remove the crud with a shop vac, clean as much crap out of the oil drainback holes, change the oil and filter and refill the crankcase with ATF. Don't drive it hard, don't drive it on the highway for hours on end. The ATF is much thinner than engine oil, doesn't have the viscosity or abilities to handle the heat of engine crankcase. What it does have is lots of detergents, it will clean alot of the gunk. It wont get rid of 20 years of neglect. Drive it around and change the oil and filter again, this time refill with engine oil

 

I'd have to agree w/Nilsson - you're just looking for trouble.
Clogged returns lead to all kinds of problems, such as a clogged oil pickup and clogged oil passages - do it right - at least pull the pan and clean it out, after the heads!!!!!!!!!!!

ETA - There was another member a little while ago with the same problem - he rebuilt it, as after the head cleaning, it just started other problems!

 

I agree with the bandaide on the gunshot wound remark, however, the mention of the tapping is a concern. What I think will end up happening is that he will clean all the gunk under the valve cover, normal for an oldsmobile, but he will still have to address the tapping. This is probably bad rocker assy/'s, and or a lifter. Then he is going to have to pull the intake, which will lead to another pile of gunk!! I would not suggest the the full ATF treatment but just a quart or 2 for 100 miles and then change the oil and filter. Remember all the stuff inside the engine will get flowing thru the bearings etc...

What I would do is pull the intake now, clean the head and intake area, remove all the lifters and check to see if any are concave. I would replace the bad lifters if any, the couple of worn rockers, and clean and reassemble everything and drive it until he can afford to do it right!

Good luck!

 

Yeah very true, I didn't buy a 95k mile young motor just to have it die....it needs to be taken care of!

 

My guess would be the lifters are not coming out the top with that kind of junk in the engine. They are probably mushroomed and need to go out the bottom of the lifter bores after the cam is removed. I have seen it more than a few times with neglected engines.

 

My perspective is just a bit different - if it ain't broke, don't fix it!

IF you can find / see any obvious chunks of stuff obstructing any holes, then by all means carefully remove them. If you want to snake a long bottle brush through the drain holes to be sure they're clear all the way through, then go ahead.

I would never pour in any liquid other than motor oil, or loosen up any crap that is not actually in the way, because you don't know what will happen next.
Right now, your motor has reached a state of filth equilibrium - all the stuff that's going to stick has stuck, and all the stuff that's going to fall off has fallen off. If you loosen stuff that's stuck in places you can't see, it can come loose later and get in the way and cause problems. If it's been there for all those miles, chances are it's not hurting anything.

Your motor has 95,000 miles on it. That means it's time for a timing chain, and that it can probably go another 30 to 50K if treated well, but that it COULD fail much sooner (depending on the level of past abuse). Because of this, plan and save for an eventual rebuild, treat it well, and figure each mile as a little happy bonus. If it dies soon, there's nothing you could have done, and it will step up your rebuild schedule. If it seems to go forever, you got lucky, and you have the luxury of choosing your battlefield. But, if you screw with it, and then something happens, you'll be kicking yourself for messing with a perfectly good running engine.

As for the tapping - investigate it as you would for any engine - localize it as best you can, check rocker clearances, change rockers or rocker pivots, or clean or change lifters if absolutely necessary, but if you're going to rebuild it anyway, don't get into it too deep, or before you know it, you'll be rebuilding it without meaning to (the "might as wells").

- Eric

 

I'm going to post a pic of what I'm talking about bc maybe I made it Sound worse than it is, maybe I didn't, someone posted a pic in another thread of a 'bad mess' and it looks much much worse than what I have, the rebuild is planned, but maybe no as critical as it may seem.. The tapping, really
only seems to be the #3 exh rocker, it has a little play as the motor turns, either way a
full set of litters and pushrods is going to be
ordered soon, may as well go with rockers too.
Of course it's a pain to do things piece by
piece, but in the end all it costs is time and gaskets, right?

So to give accurate info, bc judging by response it may seem like it's all clogged up, but it flows oil well, at least it seems to me. Ran ~5 mins, sat 10, popped the cover off and there wasn't any oil
pooled up, in fact there wasn't even enough in there to make a mess when I pulled the cover. But, after that, when it ran, I could see the pushrods flowing oil, so it's not like there was none in there in the first place. Trying to explain this w/o pics is difficult I know, but a guys gotta work, and I can't take the car without the valve covers on lol

 

9d2295a1.jpg

e41e26ae.jpg

So here it was before I cleaned anything off, any opinions? bad? not so bad?

 

Looks like a typical 40 year old motor to me. I've driven much worse (and cross-country, too).

As far as the tapping, if you've isolated it to one valve, and can turn the motor and see that that one rocker isn't depressing the valve as far as the others are (or has more play than the others), the first thing I'd do is pull the rocker pivot - if the pivot is worn, the rocker will sit high and have extra play. You can always just change that one pivot if necessary. While it's off, you can compare the wear patterns of both rockers - if they're the same, the rocker itself shouldn't be the problem - and you can pull out the pushrods (try to keep track of which is which, and what end is what, on general principle) and roll them on a piece of glass - if the affected pushrod isn't straight, there's your problem.

If all of that is good, and you're sure that it really is that valve, then you can pull the intake manifold (it is VERY HEAVY, especially when you are leaning over the fender trying to lift it up) and take a look at the lifter - it might worn or screwed up, but it might just be clogged with a little piece of crud. You can take it apart and blow it out.

See Chassis Service Manual for more information...

 

Other pages...

 

Yes, you did make it sound a whole lot worse than it really is. Possibly you might have a lifter not pumping up do to some dirt in it, or like stated above 1 bad rocker assy. You might try and swap the assy with one of the adjoining ones and see if the problem moves.

I would just scrape the little bit of sluge off, and wet a some rags with solvent, and wipe the rest of the area down.

I would then drain 1 qt of oil from my pan and add 1 qt of rislone or ATF, run the car for about 100 miles, and change the oil and filter.

 

Who said that was bad sludge build up?
That looks pristine, mine had so so much sludge the valve covers weighed about 10 pounds each and you couldn't even see the rocker arms.

The really bad sludge is also caused by never letting the engine warm up enough, old lady cars driven a few blocks once a week to church and back are the worst.
My engine had 60,000 miles put on it in 20 years and the original owner told me he drove it every day of the week to work and also used the car to haul his boat back and forth to the ocean and for family road trip vacations.

 

Agreed. That is not bad at all. I opened up motors you could not see the bottom half of the rocker.

 

Well now I've got something else, there's a knock, almost like someone knocking their knuckles on a countertop, and the oil light flickers a idle intermittently. It's loud enough to hear in the drivers seat. When I pull the plug wire to #5 it changes tone. It goes away with a little throttle ( it'll speed up with rpms and quiet down. It doesn't do it immediately on start but will come in after a bit, or if I put it in gear, is my bottom end done?

 

HMMMMMMMMMMM? What have you done since the last post?????

 

Time for a rebuild. Its more than likely a rod. You will have nothing but scrap metal if you keep driving it.

 

Like I suggested, rebuild it.

 

All I did was vacuum out under the left
side valve cover, put in a new gasket, and put it back together and torqued it down at ~7ft lbs. (I did vacuum the oil returns and some junk came out, not a ton this and mostly thick oil) this mornin I ran it and put some seafoam on the vac line. The noise got louder

 

Yeah looks like this is my big project for the summer, now is this that a "rebuild kit" from summit or jegs will adress?

 

That does sound like a classic rod knock description...

- Eric

 

If the oil light flickers, the motor is most likely toast.
There is only 1 motor with an oil light problem that I had minor success with.
The oil filter was clogged solid with sludge, so I changed the filter, ran it with oil,trans fluid, and kerosene mixed.
It's at a whopping 14psi now with new oil. No knocks yet though

 

Well the oil light started to flicker about a mile from home and hasn't been driven since, hopefully nothing is too damaged, but I won't know til I take it apart. Any suggestions on where to ge what's needed for the rebuild?