1984 6 cyl. knocking sound

OK - i have a 1984 Chevy S-10, 4-wheel drive, 6 Cyl. engine, just over 180,000 miles. After starting at after it sitting for about 2 weeks, I noticed thier was a slight ticking sound coming from the valve cover
area - was not worried about it - have dirven it a coule of times since them, now it is VERY loud, oil presure is good, oil level is good. I took off the belts today, to make sure the noise was not coming from the alternator or the water pump, no difference - got one of the automotive stethescopes, and it is much louder on the passanger side - and of course, gets louder when the engine is going faster - will still quite loud at an idle.
Engine is not smoking at all, and uses no oil, has plenty of water - this is really the only major issue I have had with since I got it over a year ago.
I have never dealt with a rod going out, or other problems like that - so I have no idea what to look for or what they sound like - so if anyone could give me some ideas, I would love to hear from you.
If it something going on with the engine, I think it will be headed for the junk yard, unless I can sell it - it does still run, and has a new transmition in it - so it might be worth something to somebody just for the trany.
Any insight into what may be going on would be greately appreciated,
Scott
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Remove and replace on spark plug wires at a time and if it is a rod knock it will change sound went you pull wire on cylinder with a bad rod.

TheSnoMan.com
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ok - got some advice from a firend here - and I took off the valve cover gasket, and the valves obviously are out of adjustmest for some reason - with the engine running, 3 of the springs are not even being compressed - but the rocker arm is moving - so now, what is the rpocedure for adjusting the rocker arms - I have a book, but is does not say anything about adjusting them - so that is not any help, I would assume, you just don't tighten them down all the way, call it good.
Scott
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They cannot get that loose without something wearing out or failing. This is not a good sign. You might start by roughly measure the lobe lift on push rods (it should be around .28 inches) ----------------- TheSnoMan.com
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wrote:

Or look for a the rocker being broken right at the stud. They sometimes pull the ball through the rocker.
Al
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wrote:

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OK - sa far, everylooks normall - except for the lack of oil when the engine is running - going to buy an oil pressure guage tonight - that should give some idea of what is going with the oil thing - and I will let you all know what kind of pressure I am getting
Scott
wrote:

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Scott wrote:

Well being an 84 with a 2.8 I would suspect that the cam is going bad. It is not an uncommon problem with the 2.8.
First thing would be to check the rocker arms and pivots and see if maybe they are worn out. Also look and see if the studs are pulled up (measure the others and see if the bad ones are the same). If neither one of those are the problem then I would measure the cam lobe by measuring the travel of the push rods. I'm betting you have either a failing cam or failed lifters.
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ok - so i got all the valves adjusted - no change in the noise level - i did not notice while adjusting, and running the engine - that thier is no oil plashing around like one would expect - everything seems to have a oil coating - but it does not appear thier is any new oil - wonder if the oil pump is going bad - or the passageways are plugged - if the passages are plugged - how would I go about cleaning it out.
I did notice once I got the valve cover off, that thier is deeper knock - and I can hear it on one of the valves through the stethescope.
will also look into the cam thing - but with 180,000 miles, it may not be worth putting much money in at this point.
wrote:

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Have you done oil pressure check with a manual gauge? ----------------- TheSnoMan.com
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I don't have a manual pressure guage - other than the one in the dash, which I though was not wokrin - becouse it always showed so little pressure - and everything was wroking just fine - but who knows, maybe that guage is working, and I really don't have much if any pressure to speak of. Wondering if I should be other valve cover off, and see if thier is any oil coming up on that side?
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A low gauge reading together with lack of oil in valve cover area an a knock is engine all adds up to serious problems from lack of oil pressure. IF pressure is indeed low and signs suggest it has been slow death for engine and it is now in its death throes. ----------------- TheSnoMan.com
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I have an 85 S-10 Blazer, 4 WD, 2.8 V-6, with 152 K on it. Bought it new in 85. Here is my thoughts based upon all you provided in the threads. My S-10 (oil gauge and idiot light) at idle shows zero (20w-50 valvoline high mileage oil in her) oil pressure. Started this about 5 K ago after watching it slowly go down through the years. Just off idle it picks up a little and the best she does hot is about 15 to 20 psi. The engine makes all the sounds that you described and also at idle does not pump oil up to the rockers. My daughter drives the car and is off to college next month. She can't take it with her and my plan is to pull the motor then. Just has to last about 4 more weeks. The vehicle is grounded to about a 15 miles radius of our house. I really believe that is where you are at. The main bearings have wore to the point were all of the oil dumps out on the bottom end and very little makes it up.The question now that I need to answer (you may want to also) is Chevy makes a beautiful crate motor that is 3.4 L (Google GM part # 12363230) that will just bolt in. Is this what I do or should I just rebuild the original that has never left me down and had all PM down appropriately. Take care GM
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On Sat, 28 Jul 2007 19:58:40 GMT, "GM"

Go with a crate motor. There are improvements you can't see, more power won't ever hurt(especially since we're talking 2.8's here)and the warranty on the crate motor is a lot better than you'll get from a rebuilder. Oh, and you can put the motor in yourself and still get the warranty.
My '85 S-10 4x4 with the 2.8L went 358,000 miles before I wrecked it and got rid of it. I put a junkyard motor in it at about 202,000 when the original motor began behaving just as you describe. The guy that bought it put a new front end on it and is still driving it. -- Old Crow "Yol Bolsun!" '82 FLTC-P "Miss Pearl" '95 YJ Rio Grande BS#133, SENS, TOMKAT, MAMBM
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On Sun, 29 Jul 2007 22:39:38 -0400, "Stormin Mormon"

Walmart 15w40 is good for worn engine bearings too! ----------------- TheSnoMan.com
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Last time I did rocker arm adjustment was on a six cylinder Dodge van. I remember slipping a feeler gage between the valve rod and the rocker, and adjusting the nut with a box wrench. One used a 010 gage, the other a 020 gage, and I can't remember w hich.
Need to adjust with the motor idling, veyr slowly. Expect to get oil on your hands.
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