Rod knock?

Epy

New Member
Jan 15, 2009
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Florida
I have a video here, just tell me and pay attention as close as you can to tell me if you truly think that's what it is.

I put a stethoscope to it(Using a long screwdriver) and it seemed to be coming from the top.

I've already made alot of threads(other forums) and talked to mecahnics around here and they said that's because rod knock can sound up high when it hits the head, I ended up pulling the engine, but I didn't start the teardown process, on top (cams, studs,) and stuff like that look fine so far.
I got pics also. I've already pulled it anways because either way something's wrong...

also btw, the car was going nowhere(when I drove it) like when I was slamming on the pedal...
seemed like I had no compression because tranny is fine.

(startup)

(revved)


(can't seem to embed it)
 

dumbo

Supramania Contributor
Jul 16, 2008
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giving her some revs for the vid woulda helped, but i would lean towards knock, maybe a cam cap is coming loose if your sure its coming from the head.

as for the mechanic who said 'it can hit the head' trust me...you'd know if it did.

i would pull the vave covers and check cam caps, ect. doesn't hurt to cut a oil filter open and squeeze the oil outta some plights and see whats left.
 

87tomanymods

87tomanymods
Oct 25, 2008
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lansdale
www.myspace.com
ye i agree most likley rod nock but def check the lash caps under the cams make shure it didnt spit one out if it didnt check the clearences before removing the cams which u will most likley need to remove to seperate the head good luck
 

arizzle

Lov'in the boost.
Nov 1, 2006
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burnaby, BC
seems like cam cap lash! but remove the cover and inspect it but if u hold it pass 2500K RK is louder well should be. and you car would retard the timing.
 

dumbo

Supramania Contributor
Jul 16, 2008
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Albera, Too Far North
BlackDynamite;1224387 said:
MY dear god. Rod to the knock sir! That sounded EXACTLY like mine. I can tell you that the bearing is completely gone...

Here was mine when it spun a bearing.

wow yah i'd say that bearing is gona haha, love the end "She's a little dirty, I apologize." haha awesome

OP good luck, you gotta it out thats the hardest part:)
 

grimreaper

New Member
Jul 2, 2008
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I ended up pulling the engine, but I didn't start the teardown process,

we dont need to guess for you. flip it over and pull the pan. should take you less then half an hour:3d_frown:
 

Epy

New Member
Jan 15, 2009
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Florida
yes, believe it or not I DID read that thread BEFORE I made this. I just went ahead and decided to make it anyways to see how nice this community is and to get a direct response.

it seems like there's a majority. I have pics of the valve covers off and everything and close up pics, I probably wouldn't be able to spot if it was cam caps. I mean, they looked right.

ALSO btw to the person above who says it gets louder over 2500, yes it did.
It tend to get very loud.

Thanks guys, soon I will post my thread then of my build/project, since I migth as well go with that while It's out.

Hopefully over this weekend, I'll have the engine completely apart and also oil drained and shit to check for metal.
btw, I heard the hardest part is assembly, not the pull ;)
First pulled Very first two pics when first opened

p1224529_1.jpg

p1224529_2.jpg




p1224529_3.jpg


p1224529_4.jpg


p1224529_5.jpg


Very most recent pics, that's where I'm at. (bottom 3)
 

AJ'S 88NA

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Jul 26, 2007
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How many miles on that motor? Looks like it had been rebuilt not too long ago due to the shiney paint on the block and clean head on the outside.
 

Epy

New Member
Jan 15, 2009
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Florida
Yea, the sad part is, the guy before me rebuilt it, and I had no idea what he meant when a buddy of his kept saying ... "and if anything a rebuild kit is only like 400 dollars on ebay" yea you piece of shit because you dont know how to build one.

The tb is new, the water pump, clean block/head, rods, and maybe rod bearings?

On my way home from buying it... it produced rod knock. That's my theory. It was fine when we test drove it for about 15 minutes, even opening up. Then I bought, and started to drive home and it got worst as I got home. (42 miles away) please don't tell me what I should do.. it's already been thought and discussed and bought. I took care of business already...

they did a ghetto ass job, like wires were blacktaped together, some were broken, every bolt was loose and probably not torqued properly.
 

Epy

New Member
Jan 15, 2009
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Florida
So it looks like I don't have rod knock...

I mean, I don't know, I can't tell. My bearing is toasted but it wasn't spun. There was just alot of play between the cap, bearing and rod.

uploading pics and vids right now

I don't get it though, this wouldn't cause it to not 'pick up' when I slam on the pedal like it has no compression when I was driving it.
 
Last edited:
Epy;1226361 said:
So it looks like I don't have rod knock...

I mean, I don't know, I can't tell. My bearing is toasted but it wasn't spun. There was just alot of play between the cap, bearing and rod.

uploading pics and vids right now


The owners Could have spun a bearing before and when they rebuilt it, they decided the have the crank machined. BUT didn't get an over sized bearing.

Or also, they could have spun a bearing completely. Then the drove around with it knocking and it wore away at the rod, then putting a stock bearing back in...causing some slack.
 

AJ'S 88NA

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Jul 26, 2007
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Yes that spun a bearing for sure. Had you drove it much more it could have thrown the rod. Black I think hit the nail on the head, probably wasn't clearanced properly when it was rebuilt. If yopu were to plasticgauge the others you will probably find that they are not sized right either.

The only other thing I can think of to cause that is no oil or loss of pressure for some reason. Happens with the 7M under hard braking or cornering.
 
As AJ said, Plastic gauge will be the most common to check all clearances....a micrometer will come in handy also :]

Can you send me some CLOSE up pics from different angles of that #6 bearing cap?

ALSO, when you put this motor back together get some oil, that you're going to run in the car, OR some assembly lube, and lube the bearings and caps etc. Also do the same on your cam shafts. And when you get the car back together, unhook the coil wire (the wire to the middle of your distributor) and turn the car over a few times so your engine doesn't dry start. This will get the oil in the oil pump etc. Also remember to check the head bolts and head gasket...since these guys F'ed up...i wouldn't chance it... :]

AJ - I Autocross my 7m... and i drive the living shizite out of my car...never heard of losing oil pressure while cornering....Explain more about this! I'm curious now... ;]
 

AJ'S 88NA

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Jul 26, 2007
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BlackDynamite;1226699 said:
AJ - I Autocross my 7m... and i drive the living shizite out of my car...never heard of losing oil pressure while cornering....Explain more about this! I'm curious now... ;]
I had done some autocrossing also, didn't have a problem then, well didn't notice any. When I started running at Sebring, a lot harder braking and harder corners at higher speeds was when I found the problem. Threw a rod the first time, then spun 2 rod bearings after that before I realized what was happening. Under hard braking the oil was being pushed to the front of the pan and under hard corners it was being pushed to the sides, everytime it happened it was about at the same place in the course, both things happening at the same time, braking and then hard turns.

Since those very expensive lessons and this forum, I believe I have corrected the problem, a deeper oil pan with baffles and extended pick-up, oil accumulator, extra quart of oil, larger rod bearing clearences, and turbo oil pump shimmed. There are other things you can do to make sure this dosen't happen here in the threads, I think there is a stickie about doing the most you can to help, but it needs to be done when you are rebuilding.