Rod vs. Valve knock
- Thread starter eboutin88
- Start date
http://s373.photobucket.com/albums/oo175/Bri7manx/supra/?action=view¤t=PB280012.flv
Here's rod knock. The quality is shit and I didn't rev it because I don't want to scratch up the crank anymore than it has, but I think it's pretty obvious.
Here's rod knock. The quality is shit and I didn't rev it because I don't want to scratch up the crank anymore than it has, but I think it's pretty obvious.
^^
Here's rod knock.
The quality is shit and I didn't rev it because I don't want to scratch up the crank anymore than it may already have, but I think it's pretty obvious.
Here's rod knock.
The quality is shit and I didn't rev it because I don't want to scratch up the crank anymore than it may already have, but I think it's pretty obvious.
That one *is* pretty obvious, however, there are much lighter cases of rod knock. I've dealt with one where you couldn't hear anything at idle, only a tapping when you let off the throttle and the load on the bearings went from accel to decel.
yeah before i took my engine out nobody could hear it but me from 5+ people and people that watched the vids I posted of it here. To me i think its something only an owner knows at first because only you know what your engine normally sounds like.
But I definitely do believe RK and valve tick is a miles difference but I'm not gonna elaborate on it cause I think most people disagree and my ears are better than anyone I know.
But I definitely do believe RK and valve tick is a miles difference but I'm not gonna elaborate on it cause I think most people disagree and my ears are better than anyone I know.
eboutin88;1447057 said:
OEM parts had nothing to do with your engine failure. OEM parts are fantastic, and many guys on stock rebuilds make 400+rwhp all day long for years. The flaw was likely in the build or machine work.
black89t;1461057 said:
IJ.;1461146 said:
Ian, if I made add to this...
When you pull the injector clip, the injector is getting no voltage, therefore is not being told to open. If the injector doesn't open, no fuel is being sprayed into the cylinder. No fuel means no combustion in that cylinder, meaning much less load on that bearing. (feel free to add to or correct any of that)
If it was valve tick, it would always be there, because the cams are always rotating as long as the engine is running.
IJ.;1461146 said:
IJ i understand that. :icon_roll
i have used that trick on other motors. its just i don't see why you would have to replace the injector clip. i know you wouldn't say that for fun. i was curious as to why.
didn't you notice the bold. lol.
Well with the engine running, everytime you pull the injector clip the engine has a misfire. You only have 6 injectors and if you leave them unplugged the engine will run like shit if at all, thus preventing you from finding any noticeable change between cylinders.
Listening to the engine is how you determine what the problem might be.
Listening to the engine is how you determine what the problem might be.
89supra7mgte;1461344 said:
Negative, Ghostrider. If you do it right, pulling an injector clip is probably the easiest way to tell. You won't have a misfire, that cylinder just won't fire, period. When you first remove a clip, the engine will bog, but then go back up to the RPM you were holding it at. When the knocking goes away (which it will as there's no load on the bearing), you've found the cylinder that's knocking.
I've done this a few times, and it's worked every time.
Edit: you seem a bit confused. You unplug one injector at a time. If the sound doesn't go away, you plug that injector back in. You shouldn't have more than one unplugged at a time. And you ARE listening to the engine. Dunno what else you're going to do, because you certainly can't LOOK at it to diagnose RK without pulling the bearing caps.
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787m
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haha! Was gonna try IJ's injector trick, but the bastard spit out a headgasket first! Now I could care less if it's any of the three, time to go JZ...
shaeff;1461366 said:
I know how this works i was replying to the post that was asking IJ why you replace connector after unplugging. And if a cylinder does not fire isnt that along the same lines as a misfire? on a more controlled basis?
EDIT: read quote from IJ post above that was what my post was referring to. Sorry for your confusion
The knock sound won't go away by pulling the inj clips, it will just not sound as loud. At least in my case. So listen carefully.
LOL!
I think 89supra7mgte is asking why IJ says to replace the injector clips!
I mean really, IJ- why would I want to cut off and splice in new injector clips, just to verify rod knock??
:yelrotflm
I think this was just a case of misunderstanding. IJ means that after you've unplugged each injector clip, you place it back on the injector- IE; replace it.
I think 89supra7mgte is asking why IJ says to replace the injector clips!
I mean really, IJ- why would I want to cut off and splice in new injector clips, just to verify rod knock??
:yelrotflm
I think this was just a case of misunderstanding. IJ means that after you've unplugged each injector clip, you place it back on the injector- IE; replace it.