rod knock

I believe I have rod knock its consistent with engine rpm and the sound is almost dead on except that its not very loud. My question is what now? What can I do to help with the problem to prevent from getting worse? What is rod knock exactly? It just started making the noise after changing my oil from amsoil to royal purple. What do I do now I deffinetly don't have the money to buy a short block. When I do have the money what r my options

if youre asking what rod knock is, how do you know that it is rod knock?

royal purple oil is crap. it turns to water very quickly. change the oil, put something like syntec 5w-30 in and see if the noise goes away.

I've heard rod knock b4 and on YouTube and a couple of people said that's what it sounds like or a bearing. I was just meaning what exactly is happening when you have it. I will post a video of the sound in a lil while.

if you have rod knock your engine is trash.

 

is your engine making noise when the engine is at operating temperature or jsut cold ?

 

cold engine noises is common.

Rod knock happens when there is enough wear between the crankshaft and connecting rod bearing that the crankshaft "knocks" around inside the connecting rod. Because the bearing is no longer working properly wear happens rapidly if there is any noise.

 

The other day mine made a little noise at startup. It scared the #@$% out of me. I hadn't driven it in about a week, and the noise went away in a few seconds. Like frankster said this is normal.

 

Your options are.

Drive it, this will probably contaminate the oil, possibly causing damage to other parts of the engine.

Tear it down. A reputable shop may be able to install a new bearing. (there may already be other damage) I have no experience doing this with an EJ255, but I've done it on other motors with success.

Replace the shortblock.

 

Royal purple does not hold up well. I don't know what weight oil you are running, but I would suggest either mobil 1 0w-40 turbo diesel truck, or shell rotella t-6 5w-40. They are much cheaper than the oils you mentioned, and provide excellent protection.

Would a used oil analysis be able to detect anything without the need for a teardown? Several people are recommending an oil change anyway, so this would be quick and inexpensive.

 

And yes, if your car sits for several days expect it to sound like BAD when you start it. Scared the heck out of me.

If there is definite knocking type noise at all from the rotating assembly, you're pretty much hosed. The used oil analysis isn't going to tell you much beyond "hey look, bearing material" -- which you already know.

 

You can use a mechanics stethoscope to try to make sure the noise is coming from the block. There are a few other things outside the block which can make knocking sounds when they fail. Idlers/pulleys come to mind.

It does it hot or cold...so can anyone give me any directions to what I should replace or is it tear the motor down and assess the damage. My heads still should be good right? So then maybe go with an sti short block or machine shop the motor and go with new internals and bigger valves and cams?

an ej257 would suffice with your heads and everything.

+1 ^^^ 255 heads slammed on a 257 block is proven to be the best combination. Hence why the 05-06 are the best LGT. hehehhe

I can't believe you'd have rod knock just cause you used different kind of oil

Usually it's from oil starvation, engine abuse (trying to do doughnuts, over-revving, etc) or turbo failure or all of the above

If the oil turns watery, it doesnt provide good lubrication to the cylinders. So its not a smooth motion. Right?

Honestly though, the best oil I have ever used in Rotella T6 5-40.

OP take a video and post it, it just could be the normal boxer sound and your hearing it cause you used a different oil

 

Yay another oil thread

the thinner the oil gets the easier for bearing wear and provides less of a shield barrier between metal parts (rod bearing/crank bearing). Using a heavier weight oil can reduce noise especially on high mileage engines, but also can mask underlying issues. The op should try some 5w-40 Mobil 1 for turbo diesel trucks or a 5w-40 syntec, it may help with the noise. But we won't know till he posts a video of what exactly is going on. And yes, crap and thin oil can make an engine louder.

Thx bmx I will post a video soon just crazy busy. I was using amsoil 5w40 for the longest...but this last time I used royal purple so its kinda weird I hear it now using this oil.

Yeah. Take a video but change your oil to one of bmx's recommended brands or Rotella T6 5-40 (blue bottle.)

 

See where that gets you.

http://m.youtube.com/index?client=mv-google&desktop_uri=%2F&gl=US&rdm=4oox72jis#/watch?v=Iy44s5YWoEA

 

Here it is hope you can hear it well enough

That link doesn't work.

Hmmm I can view it...?

Here's a direct link.

 

[ame=http://www.youtube.com/watch?v=Iy44s5YWoEA]November 24, 2011 5:06 PM - YouTube[/ame]

 

The video is really pretty terrible and you can't really hear much. I wouldn't feel comfortable diagnosing with out a better video to clearly show the noise a bit better. However, there does sound to be a bit of knock.

Thanks for the help with the video posting!!!! Yes I know it is shitty but I will get a better one maybe if I have the video camera further away it will sound clear. It seems I will go with rotella 5w40 and see what happens...but I guess I am saving for a ej257 short block but aren't they the same as the ej255 block that is in the lgt because people say the sti block is better but I've read they r exactly the same??

that sounds horrible, does sound like rod knock. Not quite as bad as mine was when our engine died. Piston was hitting head and it was LOUD.

sounds pretty consistent hard to tell with that vid.