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ƒ=1/2π(√k/m)
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"Let me sing you the song of my people!" - MKIII Supras

Hope it's not rod-knock dude.
Really sounds like it from that driving video.
 

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Could drain the oil and have a look at it.
Cut open the oil filter and look for copper.
This. Or you could go with a Blackstone Oil analysis. It's $28 but they'll be able to give you a full breakdown of what's in the oil and it's far more precise than eyeballing it.

Something else you might attempt trying, pull one plug wire/coil at a time and put a light load on the motor. If the sound goes away with one of the cylinders not firing that would at least give you a starting point.
 

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Discussion Starter #25
I did test for rod knock with a long screw driver, no play. Also tried pulling one spark coil at a time but that only work if you can hear the knock at idle or rev. It had 3 oil changes and all looked normal.
 

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Discussion Starter #26 (Edited)
Alright i pulled the trans off today and everything looks normal. Flywheel is tight, no cracks. Clutch and pressure plate looked normal. There is some play between the pressure plate and the throw out bearing but i think thats normal. Other then that im leaning towards the bottom end now.
 

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ƒ=1/2π(√k/m)
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Alright i pulled the trans off today and everything looks normal. Flywheel is tight, no cracks. Clutch and pressure looked normal. There is some play between the pressure plate and the throw out bearing but i think thats normal. Other then that im leaning towards the bottom end now.
Yeah. Will be interesting to see the mains and rod bearings.
 

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475RWHP 449TQ and climing
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You didn't have a rod cap torqued properly.....forget about it pull the motor and get the crank properly done. That rod needs to be cut and resized. If those are rods that never been replaced or resized do all of them. Cheap build, poor assembly, and piss poor tuning will cause rod knock from the word go. Since your friend had the same problem I'd say you both need a lesson in proper engine assembly.....no disrespect intended.

I've made a bazillion post about this with the 7mgte, and the 2jzgte is no different when assembled improperly.

Hey Brent.....and everyone else
 

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I've made a bazillion post about this with the 7mgte, and the 2jzgte is no different when assembled improperly
Kinda goes for all motors to some extent. Always entertaining to see people bag on the 7M, then turn around and have the same issue on the 2J.

Hey Brent.....and everyone else
 

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Discussion Starter #32 (Edited)
Update on this....

I slapped on a different transmission with a stock pressure plate and stock clutch, new throw out bearing and pilot bearing, same knocking still there.


I pulled the motor, checked all the rod bearings and main bearings. They are all clean, no scoring or anything bad. At this point I dont know what else to check that could make that knocking/tapping. Its been a nightmare trying to diagnosis this knocking noise.
 

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ƒ=1/2π(√k/m)
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got any pics of the bearings? It’s gotta be something in the rotating assembly id think.
 

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Discussion Starter #34
I should of took some pictures, i already put everything back In place with the oil pan. Ill take some pictures tomorrow.
 

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Discussion Starter #36

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ƒ=1/2π(√k/m)
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Man, I agree with you. Journals and bearings look pretty good, minus one looks scarred a little.
No signs of heat/wear. (discoloring.)

Any noticeable play in the wrist pin at the piston? That clacking was coming from somewhere.

Maybe piston slap.
Could take the block to a machine shop to bore mic it.
Curious now, did you compression test this engine? (I'll re-read your thread to see if you did.)

Literally in the first post.. ~200psi... This is frustrating. haha.
 

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Discussion Starter #38 (Edited)
Yeah this is frustrating, im like out of ideas what this knocking is coming from. The bottom end was the last thing to do. Really in person it doesnt sound like a rod knock. Ive heard rod knock before and it doesnt sound like that.
 

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Discussion Starter #39 (Edited)
Ok got the pistons and rods out, looks like piston slap is my problem but not 100% sure. Not sure why its slapping when its already warm and comes on when driving but revving in neutral has no knocking. Still holds good compression 200psi-210psi. Gotta take my block to machine shop to have them check the bores, check the clearance From piston to wall.
 

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So, I can't get another look at the bearing photos to confirm this for some reason. But I just compared yours with apx 2500(?) miles on them with mine removed from a 114k 7MGE. Your rod bearings looked like the wear was already through the Clevite's grey top coating, where mine are not. So I think your bearings may be too tight. A couple things you can do. One - use Plastigage to check the clearance. Two, put just the rods on the crank with the caps and bearings torqued with oil during assembly. Will the rods fall down by themselves if pushed away from straight up? If not, that's another indicator the rod bearings are too tight. If this is the case, then the too tight bearings are exerting a piston push against one wall noiselessly from being too tight on the rotating crankshaft, then slapping the full distance to the other side when ignition happens. Not happening with free revving so much would also follow, as when you load the rod bearings by making the engine "do work" the friction also increases because there is not enough oil film and the extra rod pressure causes extra rotating force on the rod/piston. If I were a betting man, Plastigage will reveal those are too tight. And I also think your pistons are indeed not sized right (too small). If you had only one problem or the other, I think you'd never have noted this. For instance, the bearings are increasing the tolerance through wear and that would have gone away if the pistons were the right size. YMMV
 
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