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> Got Another F-ing Problem, Stupid Knock
Nor.Cal.914
post Feb 21 2006, 11:14 PM
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Well, just after the rebuild on my 2.0 liter, I get to enjoy the lovely sound of a stupid knock. I got home a little while ago and my dad said he heard some popping like there was a miss. I told him I didn't hear anything and pretty much thought nothing of it. Well I just went back outside to start it up again and see if I heard the popping he was talking about. And what do you know, a god damn knock is there. Definetly sounds valve related again, but I'm hoping to god it isn't anything bad that would cause a shitload of damage again. Is there any chance that I could be lucky and it's just like a loose valve for some unknown reason? I mean is there anything it could be besides a f-ed up valve that's hitting the piston and is threatening to the well-being of the motor? Please let me know. If this is a problem that's going to involve money to fix, there goes my car! (IMG:http://www.914world.com/bbs2/html/emoticons/sad.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/sad.gif) Thanks everyone
-Chris
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Nor.Cal.914
post Feb 22 2006, 12:55 AM
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Anyone got any good ideas on if this could be something that I shouldn't worry too much about? Please let me know! Thanks
-Chris
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alpha434
post Feb 22 2006, 12:56 AM
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No, dude. You're screwed. Noone else wanted to just say it.

Sorry!

Maybe a bad valve spring.

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redshift
post Feb 22 2006, 12:59 AM
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Oh, could ba a flat cam.... both sides?

Loose studs... lose exhaust... don't drive it.


M
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Nor.Cal.914
post Feb 22 2006, 01:02 AM
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I know it's nothing exhaust related. I can definetly tell by the noise. I'm for sure not driving it for fear of having something really bad happen. It couldn't be a bad valve spring because they're all brand new. Just had the heads rebuilt with brand new valves and springs during the motor rebuild. I'm just praying to god this isn't something bad, but we're pulling the valve covers off tomorrow to check the clearances then we're gonna go from there. I'll update on how things turn out. Thanks
-Chris
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Dave_Darling
post Feb 22 2006, 01:15 AM
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Sometimes parts are bad out of the box. Don't assume a new part is good just because it's new.

Sounds like a good plan to check the valve clearances and inspect the upper part of the valve train. If you don't see anything obvious, try running the engine while checking around with a mechanic's stethoscope. Or a piece of vacuum hose. That can help you isolate the part of the engine that the knock is coming from.

Good luck!

--DD
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Nor.Cal.914
post Feb 22 2006, 01:29 AM
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Thanks Dave! Well hopefully we can figure out what the damn problem is. Again, I'll post up once I find anything out. Thanks
-Chris
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Joe Ricard
post Feb 22 2006, 08:42 AM
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YA know there could be a bunch of things. Like Dave said parts CAN be bad out of th box. That's why the good engine builders check and measure shit before builind up an engine the final time.

Measuring valve springs is always good. mocking up a motor and measuring clearance/ interferance IS REQUIRED.

Not that you didn't do this but .......

Knocks can happen. Check the easy stuff 1st even if you are absolutley positive you think it's good.

an exhaust leak at the head can be loud or just a subtle wierd sound. got a exhaust stud not pulled up tight? only takes one.
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type47
post Feb 22 2006, 08:56 AM
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what follows is a very uneducated unexperienced comment only. could it possibly be a piston slap caused by installing the piston "upside down"? since it's a 2 liter, the piston pin is offset and the piston should be installed with a certain "orientation" using the mark on the piston top toward the flywheel.

just a wild guess
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John
post Feb 22 2006, 09:22 AM
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Just a side note, is the knock only with the clutch out (internal trans parts turning but car not moving)?

If the knock goes away when you press in the clutch pedal, it could be something inside the tranny instead of the engine. We had a tranny that did that just before the trans died....

It would make a kind of clunking with the car in neutral with the clutch out. Sound went away with your foot on the clutch.

I'm not entirely sure what it was, but we ended up breaking all the teeth off of the 4th gearset.
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Nor.Cal.914
post Feb 22 2006, 03:52 PM
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Hmm never thought about tranny problem. I'll definetly check that out too when I get home. We're checking the valve clearances first just to make sure nothing is wrong. My dad said when he pulled the valve covers off he didn't notice anything wrong. This worries me quite a bit because when the same kind of thing happened last time, we didn't notice anything obviously wrong at first until we pulled the head off. I'll check everything that has been suggested once I get home and see what I come up with. Thanks for the advice so far
-Chris
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Nor.Cal.914
post Feb 22 2006, 07:16 PM
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Well we figured out what the problem was. We started out by checking the valves for cylinder 2, they were a little tight, but nothing way out of the ordinary. Then we get it set up for a valve check on cylinder 1. It was extremely loose and it seems to be that the valve seat for the intake valve I believe it was has slid out and is allowing the piston to hit the valve. Hopefully it was caught early enough and we can have it back together again sometime early next week. Thanks for your help everyone
-Chris
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Jake Raby
post Feb 22 2006, 07:53 PM
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Ah...
a dropped seat...

Someone skimped on the heads and got bit in the tail!

Please listen when we say that ALL valve seats MUST be replaced!

Sorry to hear it man. Let me know if we can help.

BTW- Inspect that piston VERY closely and have someone thats a TIV jead specialist do the re-install for you- OR you'll be right back here again! Pull both heads and do ALL the seats, anything else is just plain skimping!
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Nor.Cal.914
post Feb 22 2006, 11:12 PM
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Yeah well what pisses me off is that we did just have them all replaced during the rebuild, but apparently they weren't done well enough to hold up together long enough. We're taking them back and having them re-done so I can get my damn car back and hopefully be in the clear for at least a long while. Thanks for the support everyone
-Chris
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Dave_Darling
post Feb 22 2006, 11:26 PM
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I know your pain, dude. Dropped 3 seats within a few thousand miles of each other... (IMG:http://www.914world.com/bbs2/html/emoticons/sad.gif)

--DD
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Jake Raby
post Feb 22 2006, 11:42 PM
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Who did the work on the heads??

All those that say it's not a Science with the TIV are the ones that create issues like this.

Its all in the material and the procedure.

Going back to the same guy would not be too bright-
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