s10 either rod knock or valves dying
 

how the heck can you tell? Whats a good way to test to see what it is?

either way the engine is trashed... why does it matter? I suppose you could run the engine with the valve cover off and look or get under the car and try to hear the oil pan.. Though if I had this problem, I just would either rebuild or just trash it considering that both problems are serious.

A compression test would tell you if it is a bad valve. A bad intake valve will usually make a popping noise out the air filter. In general, a bad valve will also usually cause a miss at idle.

A rod bearing noise will get worse under load. Heavy (20w-50) oil would make the rod bearing more quiet. Usually you will hear a rod bearing knocking for a second or two at startup (when oil pressure is building) before it gets bad enough to knock all of the time.

Do you have hydraulic lifters? It could just be a collapsed lifter and you are just hearing a huge tick. Use a broom handle to isolate where the noise is coming from (one end to your ear, the other end against the block)

Where are you located? I have a 1994 S10 2.2L engine that runs great that I'm planning to sell.

I think that may only work for an intake valve... if it is an exhaust valve that is going bad, the popping will be out the tailpipe.

well i prolyl should have gave more info:

its a 1995 chevy s10 2wd 4 banger (2.2L)

for years now and prolly the last 50K miles at startup cold engine it would tick and sound like popcorn being popped, drove great tho, same power, no stumbling.

it would ALWAYS go away (obviously dead of winter would make the tick last longer till the oil warmed up) well its not going away anymore. same power it seems but when im driving in the open i cant hear the tick but if i get near a curb or a wall (drive thru, atm, alleyway) i can hear the sound.

oil psi according to the guage is about 60-80 driving 40 idle and it does change with rpm.

it does have hydraulic roller lifters.

reason i need to know is to replace the lifters, headgasket, head bolts its only going to be ~$170 in parts (i do the labor, ive had another 2.2L torn apart so its easy to do)

if its rod knock im pretty well screwed or have major work that i may not want to do...

even tho the sound is getting worse it starts fine (seems i have to crank it an extra second sometimes tho) runs fine (no stumbling or bogging) still has the same power (can haul 1000lbs of rock still)

heres a video of it this past winter (it was near 0*F on the first start in 4 days)

https://www.youtube.com/watch?v=28IRZ9l2MCE

it used to go away 100% (i know it sounds pretty bad now)

ive always ran 5W30 conventional oil

I think it is more likely a lifter. A small rod knock would likely get pretty quiet as soon as the oil pressure came up (5 seconds after starting) and then might come back when the oil got hot and thin- especially under load.

A sticky lifter would likely take longer to quiet down. Load wouldn't make a difference for a bad lifter and eventually it would tick loudly all of the time if it stopped working completely.

Start it up and try to pull a big trailer or try to start on a hill- in any case, put a load on it and see if the noise gets loader (rod) or stays the same (lifter).

Listening with the broom handle should quickly tell you where the noise is coming from. You have to put the handle against your skull to "hear" it.

I had moderate success with a sticky lifter (chevy 305 v8) substituting 1 quart of ATF for engine oil. The ATF is supposed to have more detergents than engine oil. The lifter was quieter and acted up less than it had been- but it wasn't as good as new.

i'm w/ Erik. i've had several GM vehicles w/ noisy lifters. they never got that bad tho. amsoil 40 weight quieted them down. i've heard about the use of tranny fluid as well.

well i had the local school bus mechanic (friend of the family) take a look at it with this expertise and mechanics stethoscope and he believes its the lifters too for the same reasons listed above, temperature really affects it (thats dead of winter so super thick) summer it goes away ALOT faster and not as loud on startup.

sooo $170 in lifters, headgasket, headbolts and i should be good to go.

I've heard you have to preload lifters when their new before you install them. I've heard of submerging them in oil and slightly pressing on them to get the air out. Is that true?

Also another thing the auto parts store suggested is to have the head magnafluxed for cracks. Its never leaked any coolant and compression is pretty even across them all so would you recommend doing that?

Another question is its pretty inevitable to get coolant in the oil when you remove the head. i literally JUST changed the oil in it 2 days ago. Can I drain the oil and save it to put back in?

I plan to drain the coolant and flush the system anyways but plan to put green back in instead of the dexcool orange (havent had any problems with dexcool but we have a crapload of green antifreeze sitting around the garage) would you guys recommend draining the orange, replacing lifters get it back together, fill radiator with straight water running it and treat it like a regular coolant flush? We usually just drain coolant into buckets, run truck with garden hose till clear water comes out (heat on in the cab) then drain that and refill with 50/50 mix. Do I have to do anything special because Im changing colors?

Even if it's a rod knock (which it probably isn't), if the crank shaft is still in good shape (check with a micrometer), it's not that difficult a fix. Just annoying.

Have you tried running something like Rislone through the engine, then changing the oil again? BTW, I wouldn't save the oil in the engine...oil, even now, isn't THAT expensive.

Does the auto parts store have a machine shop attached? That does magnafluxing? If so, they're probably looking for an add-on sale. That said, it wouldn't hurt, and if it did show up a problem...

the autoparts store that suggested that was advanced auto (same as checker)

i dont think they have a machine shop attached.

ive tried countless stuff and none seems to last long. valve medic (supposed to free sticky lifters/lube them/seal them) works the best for about a week then back to clackety clack. the engine restore in a silver metal can does seem to do wonders but is short lived.

ive tried some oil additive (stp somehting that makes it super sticky so it clings better, supposed to help) i think that made it worse personally haha.

well like i said ive maybe driven a whopping 20 miles on this oil and filter so id like to reuse it (im saveing it no matter what, maybe change some lawnmower oil or somehting)

yea i figured magna fluxing couldnt hurt but theres been no leaks and runs beautifully besides the clacking haha. plus its like $40 + time for them to do it.

i plan to clean up the head real good. ill take pics of everything so you guys can see what 158K mile engine thats run on dino oil looks like.


lol and its true, i changed the chevette oil today and those cars cant run without coating the whole underside in oil... it looks like it leaks from everywhere but level never goes down...

I don't see why you can't drain and re-use the oil. Drain the coolant before the job too. If you think you got any coolant into the oil during the job, be sure to drain it again after the job before refilling. Maybe flush it with some old oil, if you have any.

Before you tear it apart, here is something to try- The older Chevy small block V8 rocker arms could be tightened down from under the valve cover. If yours are similar, perhaps you could just tighten the rocker that is worked by the faulty lifter a turn or two and reduce the tapping noise.

If you do decide to tear it down:
I wouldn't risk running the engine with coolant contaminated oil. I have heard that the coolant can trash the bearings.

Here's an idea to eliminate the coolant/bearing issue:

Drain the coolant and replace with plain water. Run the engine.
Drain and replace with plain water. Run the engine.
Drain and then pull the head. If anything enters the crankcase, it will be plain water- which will not hurt the bearings and will boil off completely when the engine gets hot after the job.

The other issue is small chips of head gasket material that fall down into the oil return passages as you scrape the block clean- changing the oil helps get rid of these. Maybe you could just flush the passages out with a funnel and a quart of cheap oil after you finish scraping (leave the drain plug open). Stuffing rags in the holes while you are scraping will also help minimize this.

This website mentions "plastic lifter guides" https://www.enginebuildermag.com/Arti...2l_engine.aspx That could also be part of the problem.

Expect to spend at least 1-2 hours cleaning off the old head gasket material. Just don't gouge the head or block surfaces (which is easy to do if either is aluminum). Don't be tempted to use the abrasive disks (that you put on the end of a drill) to remove head gasket material if the surface is aluminum. You will remove aluminum from the surface and make the new head gasket less likely to seal (I found this out the hard way).

yea ive done headgasket jobs before so i aint worried about it. i had to do it on the chevette but cant remember the steps i took to do it...

i could always drain the good oil and coolant, do what you said replace the coolant with water and fill the truck with cheapo oil or half full bottles (we have tons of half filled bottles around here i can use)

yea i knew about those bastard plastic holddowns. that is a very good site tho, thanks for the link.

Re: s10 either rod knock or valves dying
 

update?...

Re: s10 either rod knock or valves dying
 

havent had time to fix it, started a new 3rd shift job that is turning out to be craptastic haha. trucks still tickin away

Re: s10 either rod knock or valves dying
 

My S10 sounded like that. I was certain it was collapsed lifters because it was worst at startup.

The factory manual said the temperature sender to the pollution control crap can cause knocking if defective. Mine read open. Replacing it ($10.46 including tax, NAPA) made the knocking disappear 100%

At 77 degrees F it should read about 2700 ohms across the two spade terminals on the sending unit with the connector removed.

At operating temp it should read less than 1000 ohms.

Re: s10 either rod knock or valves dying
 

what year is yours? mines still OBD1

Re: s10 either rod knock or valves dying
 

Did you ever figure out what was causing the noise? Unfortunately my girlfriends truck is doing the same thing.

Re: s10 either rod knock or valves dying
 

just run a good cleaner like seafoam or transmission fluid in the crank case several days before you change the oil. then, run a TRUE synthetic oil, like mobile1 or amsoil when you do change it. try a 40 weight variety...stay AWAY from 20 weight!