Rod Knock?

[Cokedoctor]

Hey peeps, this is my 1st post ever on SupraMania. I just bought my first Supra, an 89 GTE 5 speed with 122k miles on it. As soon as I started driving it, i noticed rod knock. I had my friend Joseph come over, and analyze it better for me, since I'm a newb at these engines, and we took the head apart, and checked camshaft caps, and there journals. The cams are VERY beat, and the cam caps aren't too good either.

Is it possible that my cams are making the noise I hear, and not rods?

I have the gut feeling, I'm going to need to pull the engine out, and redo the bottom end.

What a great 1st experience with Supras, LOL. I come from the Conquest/Starion community (Starquestclub.com), where rod knock is also a popular fate for the G54B, but I've never had it happen to me, til now. :icon_mad:

Thanks!

 

[Push]

7ms* knock knock... whos there? 7m...

Just build the motor, it will be fun

 

[p5150]

2jzge->t!

 

[rumptis]

There is a big difference in the way Rod Knock sounds and the sound the cams make.

If its got Rod Knock it will make a Knock sound, as for the cams its more of a sewing machine type noise.

Might as well pull the engine and inspect everything.

 

[Kai]

Knock is most pronounced in the 2000 to 2500rpm range - and sounds very much like a clack. It'll be a 1:1 with the engine speed.

Rod knock is common on these engines if they've been poorly maintained. Word of advice - when you rebuild it - use an extra quart of oil in it. Comes in handy sometimes....

 

[Cokedoctor]

Yeah, I'll be pulling the motor shortly.

 

[a_sesshoumaru]

Knock is most pronounced in the 2000 to 2500rpm range - and sounds very much like a clack. It'll be a 1:1 with the engine speed.

Rod knock is common on these engines if they've been poorly maintained. Word of advice - when you rebuild it - use an extra quart of oil in it. Comes in handy sometimes....

:aigo: i got rod knock then, luckily i am just waiting for my rods to start my rebuild :naughty:

 

[mkiiSupraMan18]

It's not a knock 'til it does it at idle...

Go ahead and pull it and rebuild it. You'll be glad you did.

Oh, and welcome to the mkIII lifestyle.

 

[slidebabyslide]

Better hope your crank does not look like mine when you pull it.

 

[bigaaron]

www.driftmotion.com/MOV03425.MPG

 

[p5150]

funny vid

 

[3p141592654]

If it goes away when you disconnect the sparkplug lead on the affected cylinder then it's rod knock. Valve problems will not be sensitive to removing spark.

7M cam journals always look bad due to a soft coating of mystery babbit like material. The cam caps should be mirror smooth though.

 

[p5150]

The cam caps arent coated - the journals look jacked because the aluminum from the head sticks to them.

 

[Cokedoctor]

Well, last night me and Joseph put the top end back together, after cleaning up the cams and caps best we could. Something I noticed...I drained the oil, and strained it, with a paper towel. The towel did not catch ANYTHING. The oil strained out clean. No metal, bits, or anything. Seems odd...rod knock should be the sign of metal shredding in the crankcase, i'd assume. What do you think of that?

 

[2543arvin]

I would check the bottom end with a stethoscope, and if you can hear it there as opposed to in the head, then it could be a rod knock.

 

[eman2289]

http://youtube.com/watch?v=B0Zq6-YaKDU

Mine with rod knock.

 

[mkiiSupraMan18]

Check to make sure your harmonic balancer is tight. That sounds like RK. :icon_bigg

 

[veedubin]

Check to make sure your harmonic balancer is tight. That sounds like RK. :icon_bigg

pulled my god d*mn engine aprt because of that!!!! BTW.... you should not be able to remove the crank bolt with a 3/8" drive ratchet!! like i did with mine. so ye be very sure that it is rodknock before you go pulling it. But with mine i'm glad i did, it'll give me a chance to do things my way..

 

[mkiiSupraMan18]

Another thing to check is loose flywheel/flexplate, check to make sure the flexplate bols aren't hitting the engine or anything lie that (masking tape on the ends of the bolts and see if any gets torn off)

 

[p5150]

you wont necessarially have lots of metal in your oil until your oil filter runs out of mesh