sounds like rod knock, maybe?

[krazydbiker]

Alright heres the deal, i have a 97 gst, evo3 16g, 550's, 8lb flywheel, 255 warlbro, safc2, anyway, it was running 20lbs when I bought it, it has 130,000 miles almost, and yes its a 7bolt. so I was driving the other day, and I noticed the turbo was spooling but I had no power, then I started to hear a slight knock, but my axle was going and broke on the way home, so i assumed it was that. replaced the axle, took it up the street and it started knocking, not loud but I could hear it, so i thought maybe it was the lifters, as it sounded like it was coming from the valve cover. Cleaned all of them this morning, let them clatter, finally smoothed out, noise is still there . I know to drain the oil and look for shavings but its raining at the moment. i unplugged every injector, one by one to try to diagnose it, but it still did it. oil level is fine, i dont get it im stumped till I drain the oil. Just looking for possible answers or maybe i should just yank it and drop in a 6 bolt. Any ideas/suggestions?

 

[TSG59_Steve]

Sounds like what happened to my car right before it spun a bearing. Loss of power/ oil pressure gauge started freaking out/ knocking - got worse.

Anyway... now I'm six bolt. . Good luck. PS> Use a magnet through the oil, it's easier to find metal shavings that way.

 

[Defiant]

it was running 20lbs when I bought it, it has 130,000 miles almost

It's beaten past dead. If it still has a rear balance shaft, its bearing is blown.

 

[krazydbiker]

Thanks guys, I'm gonna drain the oil today and see whats up. If its the rear balance shaft bearing can I just go out and buy one, or probably order one from mitsubishi? Or would it be better just to do an eliminator kit for now? And I know its beat, i was in the process of saving for a 6 bolt, but this is my daily driver also. So if the bearing was blown would that throw metal peices in the oil also? I'm assuming it would.

 

[krazydbiker]

One more thing, I unplugged every injector again, and it still keeps "knocking." now generally that would be a good thing in the sense of knocking, would the rear balance shaft ALWAYS make noise? or just when you rev it up? I could take a sound clip if that would help, and it sounds like its coming from behind the motor too.

 

[krazydbiker]

Alright, well I drained the oil, no shavings, nothing even with a magnet. What do you think? Like Defiant said, think it's the rear balance shaft bearing?

 

[Mr Peepers]

A vid would be very helpful. When my rear balance shaft bearing spun, no shavings came out when I drained the oil. When I removed the pan they were all sitting at the bottom, along with the bearing.

If it was the balance shaft bearing you might as well eliminate them so it can't happen again. Most likely the bearing seat has been worn away from the balance shaft scraping and banging on it. It won't be easy either way.

Any driving with it like that is putting excessive strain on your timing belt, mine had rubber "dust" deposite around the inside of the timing belt cover from when I was forced to limp it to work a day(horrible idea).

http://www.dsmtuners.com/forums/showthread.php?t=262587

 

[krazydbiker]

Thanks, looks like fun removing those, meh I just drained the oil so I don't know if I'm going to put more oil in it just to start it to take a vid, but it didnt make noise at idle, just when reved, but it just doesnt QUITE sound like a rod knock to me. The engine doesn't sound horrible like when my honda did it. Only question is, when yours spun the bearing, did it knock all the time or just when the rpm increased?

 

[TSG59_Steve]

Thanks, looks like fun removing those, meh I just drained the oil so I don't know if I'm going to put more oil in it just to start it to take a vid, but it didnt make noise at idle, just when reved, but it just doesnt QUITE sound like a rod knock to me. The engine doesn't sound horrible like when my honda did it. Only question is, when yours spun the bearing, did it knock all the time or just when you revved it?

Mine didn't make any noise when it spun at first but after a bit it got worse and worse as less and less of the bearing was left over.

 

[Mr Peepers]

I believe mine was thrown out of the seat as soon as it happened, and had an obvious constant noise that went with rpm. At idle it wasn't too obvious, but around 3k rpm you couldn't miss it. Vid please, the sound still haunts me

 

[h8r]

If your oil filter is doing its job... You should be able to cut it around the seam at the top , take it apart and inspect it for metal.... Alot of times you won't get metal in the drained oil...but loaded in the filter.

 

[krazydbiker]

Alright thanks guys , well mine just happened all of a sudden, changed the axle, took it up the street, heard a knocking, took it back to my house. I'll probably yank the filter while I'm at it, I might throw some oil in and take a vid, but it will be tomorrow. Except I don't have a constant noise, which is bothering me cause I've heard rod knock before and it sounds very familiar, except for the fact that in my Honda it came from the front of the engine and was very distinct, and this sound seems to be coming from behind. Looks like I'll be getting the eliminator kit, and checking all the rods this weekend.

 

[Mr Peepers]

Vendors will probably hate me, but you really don't need the eliminator kit. If it was the rear balance shaft bearing that spun, there is no oil galley, so you don't need a bearing/plug to block it off. There are many articles on how to do it for free, using your existing bearings.

p.s. the noise seemed to resonate at different rpms. I still say balance shaft bearing.

 

[krazydbiker]

Alright, mine gets louder as you rev it, I mean its not a constant noise it sounds like something hitting something else, as from the pictures I would expect the balance shaft to just make a loud rubbing noise, but then what do I know I've only had the car for 3 months. One of my friends said to check for rod knock by unplugging the injector for each cylinder, when I did that, it didn't make a difference so that's why I'm questioning the balance shafts. Thanks for the help though, and you can remove just one balance shaft? Or maybe just for a little while to get the car back on the road? Thanks again, I've been reading about these engines every day, alot to take in.

 

[Mr Peepers]

If you removed just the rear shaft and replaced it with a stubby shaft, or sawed it off and plugged the hole going down the center, you'd want to leave the other one in to keep oil pressure up, but without the belt attached. I'd see no problem with that, but either have both spinning or none, preferably none.
By the way an easier way than unplugging the injectors one by one is using the spark plug wires instead.

 

[krazydbiker]

Yeah, the only reason I do the injectors is because I'm usually the only person working on my car, and I get lazy so I don't like shutting the car off, unplugging one, starting it back up, I'm sure you can do it with the car running, but me and electricity don't have a good history Alright, well I may just do that, I know it's hard to do it with the engine in the car, but it's possible right? Especially the rear shaft, as I have been reading. Man I hope I pull the oil pan and look up and just see the balance shaft bearing shot, that would sure make my weekend rather than a bad rod bearing. So just cut the belt to the front one, leave it in there, and then you can just pull the rear, and saw it off? I'm getting excited here

 

[Mr Peepers]

If you saw it off make sure to plug the oil hole leading from the oil pump inside the shaft. I'd recommend tapping it and putting a bolt in there with JB weld.

I have never tried removing the balance shafts with the engine in the car, as you have to remove the entire front plate. It's something I would not try to attempt personally, your experience may differ. Be sure it's the balance shaft bearing before you get too far ahead of yourself

Good luck either way

 

[krazydbiker]

Alright good thing I have all this to look back on if I find out its the balance shaft, I'll probably end up pulling the engine anyway, I want to go over the whole thing, time to buy a beater for now. I know all I have to do is pull the end caps off of the rods, and if the bearings aren't toast then I know what the problem is. Thanks for all the help though. I'll post back probably tomorrow night and let you know if I got lucky or not.

 

[krazydbiker]

Sorry, guys, have been busy all week, I just pulled the oil pan off, some big chunks of metal in the bottom. Anyway I grabbed all 4 rods after removing that stupid plate in the bottom of the engine, and none of them moved more than the other one, all had the same amount of play, maybe like 1/16 of an inch, just a rough estimate, they all made the same sound when i grabbed them. So then I look up at the rear balance shaft, grab ahold of it. It moved so much I could make it make the same sound it was making when the car was running probably had a good 1/4 inch of play . Now, I know I asked this before, but is there anyway possible to remove it while the engine is still in the car?


edit: and I checked for crankshaft play while I was down there, didn't move at all.