Finally my JDM motor is installed but it seems to be making a lot of internal noise. I believe it's mostly valve noise but diagnosis isn't my strength.

It's also running kinda rough, especially from about 1000-2000rpms, but it idles okay most of the time, sometimes it vibrates a bit more than I think it should.

Anyone run into this or have any ideas?

Edited October 25, 20214 yr by laegion

It sounds like a diesel...

Copy of Untitled_0.mp3

and again in drive (with e-brake on) at idle.

ez30d in gear idle.mp3

premium fuel?

may need live data to see where timing is....?

 

yeah, the EZ30 is supposed to get premium fuel, altho my partner uses standard grade unleaded in his with no major problems...

just curious how many miles are supposed to be on this motor?  do you have anything in writing for a guarantee of any kind? cause honestly, that does not sound very good to me

did you perform any kind of maintenance on it before installing? like checking valve clearances?

assuming you at least changed the oil & filter on it.. i hope..

 

 

16 hours ago, 1 Lucky Texan said:

premium fuel?

may need live data to see where timing is....?

 

The first tank after the swap was premium. I usually run mid-grade.

Unfortunately I have no way to log data at the moment, because my OBD port only wants to work with my ancient reader. It can record data but has no way to export it. I could do a video?

6 hours ago, heartless said:

yeah, the EZ30 is supposed to get premium fuel, altho my partner uses standard grade unleaded in his with no major problems...

just curious how many miles are supposed to be on this motor?  do you have anything in writing for a guarantee of any kind? cause honestly, that does not sound very good to me

did you perform any kind of maintenance on it before installing? like checking valve clearances?

assuming you at least changed the oil & filter on it.. i hope..

 

 

I run mid grade normally. I haven't noticed a difference, but I kinda baby it. I assumed it would just adjust the advance curve if it detected knock?

It's supposed to be less than 65k. It definitely looks it.

I don't have a written warranty.

I replaced the valve cover gaskets, exhaust gaskets, changed plugs, changed oil and filter, lubed up the cam lobes with oil, changed the pcv valve, and the serpentine belt.

I used all subaru oem parts and fluids other than the oil and filter. I used the 10w30 synthetic from napa and the 1334 napa gold filter I had for my EJ22.

I did not check valve clearances.

Edited October 25, 20214 yr by laegion

what did the old plugs look like?

17 minutes ago, 1 Lucky Texan said:

what did the old plugs look like?

Well used, but pretty normal. One had a little oil gunk around the top of the threads. They were oem subaru, the replacements are also.

Edited October 26, 20214 yr by laegion

timing chain issues would account for noise and performance issues. Early H6s had timing chain guide issues resulting in noise.  

Ive installed those timing chains but I’ve never had a chance to check timing alone. 
what year is the car?

Vacccum leak?

any check engine light?

how long did the car sit before new engine installed. 

On 10/28/2021 at 9:17 PM, idosubaru said:

timing chain issues would account for noise and performance issues. Early H6s had timing chain guide issues resulting in noise.  

Ive installed those timing chains but I’ve never had a chance to check timing alone. 
what year is the car?

It's a 2003.

On 10/28/2021 at 9:18 PM, idosubaru said:

Vacccum leak?

any check engine light?

how long did the car sit before new engine installed. 

No vacuum leak, no CEL, it sat for a day or so.

sorry for a dumb question but all we have is a screen. You’re positive it’s internal and not exhaust shield rattling?

Early H6s have known timing chain guide noise issues. Without more facts or data to tell that’s the obvious starting point.

Get a stethoscope on it and see if it’s the front, right, left, top, bottom of the engine.  Might be hard to tell since chain and valve components aren’t mounted to external covers. But you should get a sense for if it’s left right or center and maybe front?

On 11/8/2021 at 4:31 AM, idosubaru said:

sorry for a dumb question but all we have is a screen. You’re positive it’s internal and not exhaust shield rattling?

Early H6s have known timing chain guide noise issues. Without more facts or data to tell that’s the obvious starting point.

Get a stethoscope on it and see if it’s the front, right, left, top, bottom of the engine.  Might be hard to tell since chain and valve components aren’t mounted to external covers. But you should get a sense for if it’s left right or center and maybe front?

It's possible that some of the noise is exhaust shields; but the majority sounds like valves. However there is one tapping sound that is louder than the others that seems to go away when the transmission is in gear.

My mechanic acquaintance thought it might be the "flex plate"; which I didn't check the bolts on before install so I separated the engine from the transmission and replaced the flex plate with the one from my other motor just in case it was bent or cracked somewhere I couldn't see.

It is a little more quiet now that I switched to OEM oil and filter but it's still far more noisy than it should be especially with "65k" on it. I don't know what the other sound is of course I am worried it could be the start of rod knock or severe piston slap but my friend doesn't think it sounds like piston slap. The strange thing is that it seems to be somewhat intermittent.

Also the engine does a strange thing when letting off the throttle at cruise; the RPMs will drop down below 1k for a second and it will feel like it's engine braking but then the RPMs will jump back up to normal after a second or two...but this is also intermittent.

I was able to do a little bit of data capture with my ancient OBD interface but I need to convert it to a spreadsheet to make it usable. I'll post when I have time. Maybe it will help shed some light on this issue or others.

Very interesting. I’d  get a mechanics stethoscope and narrow down front rear left right fuel injectors etc. and check exhaust shields   

ive seen H6s with tight exhaust valves but never noise or guide issues. 

Certainly check crank pulley bolt and flex plate bolts are tight, and try without the serp belt, and make sure the crank pulley isn't rubbing the front cover (I had that happen, the rubber degrades).

 

On 11/10/2021 at 7:52 AM, idosubaru said:

Very interesting. I’d  get a mechanics stethoscope and narrow down front rear left right fuel injectors etc. and check exhaust shields   

ive seen H6s with tight exhaust valves but never noise or guide issues. 

I am not sure yet as I haven't gotten a stethoscope yet; but I believe it's a combination of things; possibly chain tensioners that sat for too long and are now not providing correct tension at idle; and/or 1 or more dirty injectors, and/or more weak ignition coils.

The valves and chain may be making noise than necessary but the main issue I think that I was perceiving as extra noise is an intermittent miss; it doesn't throw a code but if I drive it too much like a grandpa or let it idle for more than 5 min it will have a slight miss until I do a medium (30% throttle) pull from a stop then it will run fairly smooth for a while (still not as smooth as I feel a flat 6 should be; but maybe the EZ30 isn't naturally as smooth as the EG33 is supposed to be?).

Thankfully I've got 12 injectors and 12 coils to choose from; just need to do some testing.

leaking VC gaskets could be causing a miss. check coil boots for oil.

7 hours ago, 1 Lucky Texan said:

leaking VC gaskets could be causing a miss. check coil boots for oil.

Seems unlikely as I just replaced the valve cover gaskets with brand new OEM gaskets.

So I’m surprised this hasn’t mentioned this yet, but how are the idler and tensioner bearings on the serpentine belt drive? They are notorious for failing and making noise on the H6’s. Pull the seep belt off and start it to see if the noise goes away. If the bearings are bad, you can replace just the bearing in the on those metal pulleys.