Newly Minted 257/WRX hybrid -- rod knock or noisy valvetrain?

[wigglesxjr]

Hey guys,
just wanted to thank all the guy on here, especially DrinkAV8 and everyone else who has posted up their hybrid build stories -- I'll shortly be doing the same as soon as I can get the kinks worked out. Those include:

1) chattery/shuddery clutch (ugh)
2) strange knock/tick from the driver's side

SETUP:
EJ257 shortblock (new)
cleaned/decked WRX heads
STi head gasket
stock turbo/accesories
downpipe, prodrive axle back

I noticed this knock/tick shortly after starting up the engine...though I'm not exactly sure it was present during the first time that I started my new hybrid up. The noise is RPM dependent, and at idle I estimate about 350-400bpm at my 750-800rpm idle (worrying).

video of my problem:
http://www.youtube.com/watch?v=Z1Vb4uvRQME

haven't taken a look at the oil yet, but thought I'd get some opinions here first. THanks much.

-JT

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[reddevil]

how long has the motor run? miles?

[wigglesxjr]

Reddevil,
I have about 3 miles on it, but I noticed it after during it's second or third start/idle in my driveway, each about 2-3 minutes. Not sure how long its been there.

-JT

[LiquidForce]

is it a stock 2.5 short block?

did you remove the buckets and possibly not put them back in the right place?

[reddevil]

Are there any hydralic lifters in the heads? If so, it can take up to (in my experience) 20 miles of driving for lifter noise to go away.

[wigglesxjr]

sorry, i didn't mention my setup at all! i edited the original post, but my setup is basically EJ257 shortblock, stock and new mated to WRX heads w/ STi headgasket.

-JT

[wigglesxjr]

Originally Posted by LiquidForce

is it a stock 2.5 short block?

did you remove the buckets and possibly not put them back in the right place?

I had them adjusted for lash/shimmed at a reputable shop -- they should be fine? He did mention than the 2 and 4 (driver's side, wheere thenoise is) seemed to be tight, but within spec.

-JT

[BigC]

Sounds like valve train noise but I'd want to make sure the thing was at OT before I worried too much about that. When it heats up and the tolerances shrink the noise should diminish some. I've got close to 2000 miles on mine and I had some noises that made me nervous too but either I'm used to them now or they've worked themselves out over time. Get a nice long screwdriver and hold it up to the valve cover and put your ear against the handle. If it's coming from that area, you'll be able to hear it clearly.

Brent

[wigglesxjr]

BigC,
I'll definitely try that along with disabling the injectors in the 2 and 4 cylinders, one at a time. The FSM says that if the sound is diminished when this is done, it is probably a rod or main bearing. i hope to heck that isn't the case -- it'd be some heartbreak to have to tear it all down after just putting it together.

So you didn't think that the clicking/tapping/forceful tapping was rod related?

Thanks for the help, definitely appreciate it an I'll keep the thread informed.

-JT

[LiquidForce]

With a new stock block I wouldn't expect any piston slap when the motor is cold. I also wouldn't think it would be rod knock unless you didn't crank the motor over for a while before starting it to get oil through the system. Even if you didn't the motor is put together with assembly lube that should buy it the second or two it takes the oil pressure to come up.

Have you checked for exhaust leaks around the #2 and #4 manifold?

[wigglesxjr]

Originally Posted by LiquidForce

With a new stock block I wouldn't expect any piston slap when the motor is cold. I also wouldn't think it would be rod knock unless you didn't crank the motor over for a while before starting it to get oil through the system. Even if you didn't the motor is put together with assembly lube that should buy it the second or two it takes the oil pressure to come up.

Have you checked for exhaust leaks around the #2 and #4 manifold?

I haven't checked, but I will when I get the chance...I did notice that when I checked the dipstick on it, it was reading below the "low" line, even though I had filled it with 4.7 quarts of oil -- is this normal on a hybrid? I wouldn't think so since the oil pan/dipstick assembly is the same...hence i think that i might have run it on low oil for a while, munching a rod or main bearing I have since added about .3 quarts,and the oil level did come up alittle...could this be the probleM? damnit.

I'll drain the oil next time I get the chance. Ugh.

so the sound on the vid...inconclusive?

-JT

[Do_It_Sidewayz]

the sound in the video sounds to me like it is too FAST to be bottom end noise. also a little too high pitched for bottom end, when the bottom end is coming apart you know, because it sounds like the entire world is coming to an end.

sounds like valve tick to me.

with hydraulic lifters there is a process of "pumping them up" which is basically like working them with your fingers in an oil bath for a while, and alot of guys do not do this.

i think with some driving that will go away

[wigglesxjr]

Originally Posted by Do_It_Sidewayz

the sound in the video sounds to me like it is too FAST to be bottom end noise. also a little too high pitched for bottom end, when the bottom end is coming apart you know, because it sounds like the entire world is coming to an end.

sounds like valve tick to me.

with hydraulic lifters there is a process of "pumping them up" which is basically like working them with your fingers in an oil bath for a while, and alot of guys do not do this.

i think with some driving that will go away

hmm..yeah, all that was on there was assembly lube...I've only driven it about 3 miles...

-JT

[Whiteghost 2.5]

I have that same issue. I have a na bottom end and just refreshed the heads and I am getting that same ticking. I have driven it about 150 miles at highway speeds and no ill effects. I will be checking my valve clearances again.

Josh

[Acostafan]

Guys, these heads DO NOT have hydraulic lifters. That noise to me says out of adjustment lash or leaky HG. I know you say you had it done at a shop, but that 's just too noisy. And that ain't an exhaust leak either.

If lash is too tight, you can throw misfire codes, too loose and you have a lot of noise for one. I'd start ruling out serious things first, like the HG. If you don't know how to test for a leaky HG let me know.

[wigglesxjr]

Acostafan, how could I check for a leaky HG?

-JT

[Josey Wales]

No hydrualic lifters.

Your valves are WAY out of spec. Pop off those valve covers and measure the lash.

I'd check your timing also.

[Josey Wales]

I just rewatched the video...

For a headgasket leak... (But I doubt you have one )

A leakdown and a compression test are helpful for testing for HG leaks. They are usually visible and you can smell the coolant cooking (in subarus). Check for air bubbles in the radiator fill point as well. Heavy white smoke from the exhaust is usually a definate. An air hose is really all you need to confirm it though.

I hate to be the bearer of bad news, but that is the noisest subaru valve-train I have heard in a while. That's pretty bad considering how far out of spec they are from the factory (I have seen +/- .2+). Did a reputable shop do the work?

Here is what I would do if I was you. Your valves are extremly loud, and the clearances are off enough to cause big problems later on.

Start by removing your timing belt. It almost sounds like your belt may have jumped a tooth too. Pop off the valve covers, and measure each individual clearance. Compare the exact measurement to what subaru requires. Also look for consistancy between each corresponding cylinder. I have seen measurements be off, but equally-off on each cylinder and the engine would run prefect. It might be something as stupid and re-arranging buckets, but you have to take things back apart to make sure. Triple check your timing belt when you go to reinstall. I have had times in the past where I was setting the timing, and would go to answer my cell and overlook the stupidest things .

Good luck!

[kingtut12]

2 years ago - I had a 2002 PSM hybrid WRX with the EXACT ticking - and it happened right after the swap. Turned out the valve clearances were way off and resulted ultimately in a blown motor (on the dyno). As crappy as it sounds - you need to get back in there and remeasure the clearances and I know its the last thing you want to do after patiently waiting for the swap to be done. I know because I SHOULD have done it myself.

[Acostafan]

So do I get a cookie or what?

[wigglesxjr]

DrinkAV8, Kingtut12, acostafan, thanks for all the input, i'mgoing to look into all of it as soon as I get the chance. you guys have been great, and have helped me a bunch getting through this crap.

I'll keep you guys posted.

anybody else?

thanks much! I'll follow the valvetrain lead first and check lash/clearances...where do i get the tools to do that? I dont' have the FSM with me just at this moment, but I'll look it up. Should have done the work myself, damn...hope it's just the valvetrain though...not the bottom end.

-JT

[mick_the_ginge]

Oh that's so valvetrain noise. I'm with the others, pull the covers and measure the lash. It does not sound like piston slap or rod knock, I've had both and it did not spund like what you have.

You just need a feeler guage to measure the lash. With the covers removed turn the engine over by hand (socket and wrench on the crank bolt) until the backside of the cam lobe that you are measuring is next to the bucket. measure the gap between it and the bucket. 0.008-10 intake and 0.0010-12 exhaust should be fine. If they are larger than this then you ahve found the source of the noise.

[wigglesxjr]

Mick,
thanks for the advice...I'll definitely go this route. If i find that a valve is out of whack, how do I go about changing out the shim without taking the cams off (shudder). is this possible?

-JT

[mick_the_ginge]

I'm pretty sure you will have to remove the cam to replace the bucket or shim. Other maybe able to comment, I've only measured, never replaced.

[wigglesxjr]

Oh yeah, quick question too...I've put 5 quarts of oil in the engine, but it's still reading low on the dipstick..should i just add more? My guess is yes...

-Joseph