Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum (#/f/index.php)
-   Engine Tech (#/f/forumdisplay.php?f=96)
-   -   SR20DET Rocker Arms and Valve problems.... (#/f/showthread.php?t=565913)

LuckyRPS13 05-19-2014 03:09 AM

SR20DET Rocker Arms and Valve problems....
 
Just to keep this short and sweet, I miss shifted to a lower gear and red line the piss out of my SR. continued to drive fine. the next time I drove it I made it about 2 miles normal calm driving and tossed all the Rocker Arms from the exhaust side only, and breaking the cylinder 4 rocker arm.

Now I replaced that rocker arm and went to start the motor and I broke the same position (cylinder 4) rocker arm again. The engine did not get a chance to start as well. After cylinder 4 rocker arm broke for the 2nd time the valve to the rear on the exhaust side was jacked up, the retainers were not seated properly, and the valve spring assembly was sitting higher than the adjacent valves. I reseated the valve clips springs ect. now that 1 valve is sitting higher than all the rest in my head.

My questions;

Has this happen to any one else?
What ended up being the problem?

http://i373.photobucket.com/albums/o...Attachment.jpg


I feel like I broke part of the valve off and it is now going up further. I just don't know. Would be soo nice to have a small inspection camera.

aga 05-19-2014 03:20 AM

i'd say you won't get out of this without taking the head off....

your luck continues i see. well, if it makes you feel better, you re making my own car problems seem tiny.

indomiekid1 05-19-2014 07:04 AM

i agree with aga, remove the head, and inspect it.
GOOD LUCK

Mikester 05-19-2014 07:04 AM

Shouldn't there be a shim and guide sitting on top of the retainers, or did you remove them for the pic?

LuckyRPS13 05-19-2014 07:18 AM

The shim and guide were removed for the picture. Tear down will have to wait till I close and move into the new house.

I am strongly debating on doing a monster rebuild, or parting the motor set out and dropping in a motor with more cylinders.

aga 05-19-2014 07:22 AM

mo cylinders, mo money. even if its not the engine that's expensive, its the whole conversion that is...

cotbu 05-19-2014 09:14 AM

Quote:

tossed all the Rocker Arms from the exhaust side only, and breaking the cylinder 4 rocker arm.
Did the guide and shims stay in place or something magical happen to where the guides and shims matched back up to their original location?

Remove the exhaust manifold, get your valve spring compressor, compress the spring and valve see if you notice anything. I agree the head has to come off!
You should probably examine the turbine wheel for damage, if you think something broke off.

Tom N 05-19-2014 03:08 PM

1 Attachment(s)
I feel your pain.

jr_ss 05-19-2014 04:15 PM

Quote:

Originally Posted by LuckyRPS13 (Post 5637323)
The shim and guide were removed for the picture. Tear down will have to wait till I close and move into the new house.

I am strongly debating on doing a monster rebuild, or parting the motor set out and dropping in a motor with more cylinders.

Just put a VE head on and the necessary pieces for it and call it a day. More power every where at lower pressures.

Mikester 05-19-2014 05:57 PM

Quote:

Originally Posted by Tom N (Post 5637701)
I feel your pain.

Dude- please tell me that wasn't taken immediately after pulling the valve cover off :coolugh:

Quote:

Originally Posted by jr_ss (Post 5637737)
Just put a VE head on and the necessary pieces for it and call it a day. More power every where at lower pressures.

Spoken like a true baller my friend~

jr_ss 05-19-2014 07:47 PM

Quote:

Originally Posted by Mikester (Post 5637799)
Dude- please tell me that wasn't taken immediately after pulling the valve cover off :coolugh:

Yeah, that was the unpleasant sight he found once the VC was removed, but wait there's more. Tom show the man what is behind door number 4.

Quote:

Originally Posted by Mikester (Post 5637799)
Spoken like a true baller my friend~

Far from it these days, just a squirrel trying to get a nut... In all honesty though, if he wants to go "all out" it's as simple as a head swap. No need to add more weight or cylinders in the engine bay.

Tom N 05-19-2014 10:27 PM

1 Attachment(s)
Cylinder #4 piston

aga 05-19-2014 11:14 PM

Quote:

Originally Posted by Tom N (Post 5637998)
Cylinder #4 piston

i would just throw the towel and get my coat.

indomiekid1 05-20-2014 06:50 AM

:-/ahhhh damn!

LuckyRPS13 05-20-2014 03:10 PM

I would say time for a a tear down, bore the cylinders, sleeve the cylinders, and completely redo the bottom end.

As for me I am going to go ahead and rebuild the whole engine. After giving it more thought, I am not going to do any thing crazy big, just an OEM refresh. I am buying a house in the next week; I know I will want to dump money into it to set the house up the way I want it. Including my new small garage.

indomiekid1 05-20-2014 03:13 PM

HAHA yep, oem refresh is good!

Mikester 05-20-2014 06:16 PM

Quote:

Originally Posted by Tom N (Post 5637998)
Cylinder #4 piston


Damn man... Sucks!

LuckyRPS13 08-25-2014 10:37 PM

I hate threads that leave you hanging when searching for an answer to a problem. so in case some one is searching and they find this thread.

I took the engine apart and was able to identify what happened. From me miss-shifting into a lower gear instead of the intended gear I rev'ed higher than you ever want to go with a stock head. I ended up putting ALL my valves into my pistons enough to put a slight bend in them, and break one.

As for what I am doing to fix this, I am installing Eagle rods, CP pistons, Total Seal rings, Seal power main, rod, thrust bearings, for the bottom end internals. Tomei cams, Tomei Head gasket, ARP head studs, BC valve springs, ect, ect.

Check out this thread for for more info as to how every thing turns out.
#/f/showthread.php?t=474939

http://i1030.photobucket.com/albums/...1D189B04C1.jpg

http://i1030.photobucket.com/albums/...3EB25E2F61.jpg

http://i1030.photobucket.com/albums/...A36DEA7A03.jpg

jr_ss 08-26-2014 08:48 PM

I had a feeling this was part of the cause. Bent valves bind in the guides preventing them from returning "level" with the other valve or at all. Then the destruction occurs.

Good luck on the rebuild, take my previous suggestion into account.

Dboyizmlg 08-26-2014 09:17 PM

I'm sorry this happened to you! I really am!

But hey, now you can do VET head(BALLER status) lol, jk.
Or build it, with aftermarket goodies.
Don't forget to hit up our good friends from MaZworx so they can do the dual rocker arm guide conversion!

aga 08-26-2014 11:58 PM

Quote:

Originally Posted by Dboyizmlg (Post 5709959)
Don't forget to hit up our good friends from MaZworx so they can do the dual rocker arm guide conversion!

dude i didnt know that. i'm gonna switch heads soon in mine so that's useful to know!


All times are GMT -6. The time now is 04:04 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
vB.Sponsors
Copyright © 1998 - 2019, Zilvia.net™