7mgte top end rattle?

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#1

(Ignore all the zip ties and other things wrong lol it's just temporary as I figure this out. It's on a MAFT pro so boost leaks wont really affect the noise)

I've recently put together this 7m after it sat for about a year. The head was off of it to replace a head gasket that had not blown (preventative maintainance). I picked it up from my friend who owned it before and hes the one that took the head off.

Before the head was removed it ran fine with no noise.

Oil pressure is around 6 at idle

The strangest thing about the noise is that it does not start happening until the car warms up. After about 3 minutes of running at idle, the noise starts. The oil was changed twice before I ran it just to ensure it was clean. There was never water in it.

I'm currently doing a valve adjustment as several were loose and some were tight. That could be the cause of the noise but I'm skeptical.

Let me know what you think gang!
 

3p141592654

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#2
If it was a lash issue it would be constant. A sticking valve might do that, but the sound doesn't seem right. Also doesn;t sound like rod knock. But pulling the plugs one-by-one will rule that out for sure.

I would put a stethoscope on the injectors. Although I've never heard one make that noise.
 

Piratetip

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#3
The speed of that horrible clattering sounds like something in the valvetrain to me.
When you are in there checking all the valve lash, look for something broken or out of place.
Valve springs / keepers / retainers ect...

I would highly recommend pulling out every valve bucket and checking all the components under.
Check the condition of all the camshaft lobes also.

That noise sounds very bad.

Also do you have any rod or main bearing issues?
Hard to tell from the video but sort of sounded like low pitch thud like bad / high clearance bearings.
Though could just be related to the valvetrain noise also.
 

Piratetip

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#4
Agree Pi, the inconsistency of the noise is really throwing me off.
You might be on to something with the injectors.
Pull the injectors wiring plug one at a time while it's running.
Maybe find something that way.
 
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#5
Agree Pi, the inconsistency of the noise is really throwing me off.
You might be on to something with the injectors.
Pull the injectors wiring plug one at a time while it's running.
Maybe find something that way.

I will try everything suggested when I get back to the car on Thursday. The motor has never had rod or mains issues just to clarify (I know that dosent rule it out, but the more info the better)

Keep the ideas coming
 

3p141592654

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#6
Another possibility is something left inside the covers like a socket or a bolt or who knows what that is getting bashed around. I wouldn't run it any longer until you pop the covers off and check for anything in there that's not suppsed to be.
 
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#7
I'm back with the car now. Everything in the valve train looks fine as far as I can tell. All the retainers are in and all the cam lobes are fine. Nothing has fallen into that area either. I'm still lost on what this could be.

I cant really check injectors while the car is apart but as far as the wiring goes they are fine.

Any more ideas? Like I said I'm completely lost with this
 

Enraged

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#8
you can check to make sure the injectors are opening using a 9V battery. Or you could send them out to be cleaned and flowed. A local shop charges around CDN$35 per injector.
 

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#9
You could put it back together and check the injectors by unplugging.
Or use a stethoscope and search around for the source.
It's awfully loud, you should be able to find it.
 
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#10
You could put it back together and check the injectors by unplugging.
Or use a stethoscope and search around for the source.
It's awfully loud, you should be able to find it.
With the intake shape it's nearly impossible for me to reach the injector plugs once everything is together.
 
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#11
Also I dont have a stehtescope on me right now lol. The thing that keeps throwing me with it is it ONLY makes the noise once the car has heat in the motor. For the first couple minutes of cold start it's not there at all. Wouldn't a faulty injector be faulty all the time?
 
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#12
I've been reading that a loose cam gear would make such a noise and only when hot... what do you guys think? I dont recall what I torqued them too but they werent all that hard to get off (granted I was using an 18in breaker bar)
 

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#13
I don't know about the hot part, but you can retorque the cam pulley bolts easily enough if you suspect them. Might also want to look at the oil pump pulley. Check if it has excess axial runout which can be an issue on high mileage motors. though I never heard any make that noise.
 
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#14
UPDATE: I've got the car back together

The noise is not there as you can tell in the first video. That was taken right after start up in about 45° weather. This was the first time it had started after the ecu was reset (hence the high idle). Also the exhaust manifold has several leaks which cause that generally gross but quiet ticking in the background

The second video was taken about 5 minutes after the first, and the noise had come back at that point. The engine was warm now and idle was closer to normal.

I listened all over the engine using a long extension, and could hear the best on the top of the middle of the head where I point in the second video. I listened to the injectors and they were perfectly normal. I took each of the spark plug wires out and the noise persisted (although slightly different as idle fluctuated). I also properly torqued the cam gears but it made no difference.

I still have no clue what this noise is. All the clearances are within spec so that is out of the question.

What else can you guys think of?
 

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#15
Only thing I can think of is piston slap. But I doubt that is it.

Does this car have a flex plate or flywheel?
 

suprarx7nut

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#17
Valve train. If the noise persists with each plug wire removed, I don't think it could be piston related.

I'm voting sticking valve.

Have you done a compression test? If not, I'd do that and I'd do it 2 or 3 times (not sequentially, don't kill your starter) through all cylinders and see if you can find one low.

I think that has to be valvetrain and if lash is correct and there's no loose components in the valve cover area, all I can think of is a sticking valve.
 
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#18
I'll have to borrow a compression tester from someone but that seems unlikely to me too if I'm honest. There is no reason for the valve to stick, at least that I know of. The head is very clean and the car runs well like it's got good compression. I guess I wont really know until i test it though.
 

3p141592654

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#20
I can't think of any easy solutions at this point. One suspect area I would look at is the cam bearing themselves. They have a tendency to wear especially at the rear of the cam far from the oil feed. But that is a teardown job to inspect. It fits the "only when hot" datapoint since aluminum expands faster than steel.

The sticking valve is also plausible. You might hook up a timing light and see if the noise can be timed to the flash for any of the plugs. Waste fire makes this a little less reliable test though.
 
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#21
I've had the cams out a couple times already while redoing the valve lash (I don't have that special tool to do it with the cams in). The cam bearings are worn a little but not anywhere near enough to cause the noise. I've seen others with worse bearings and there was no semblance of a noise. I'm getting the compression tester today and I'll post the results tonight
 
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#22
Here is what the compression test results were ( I did it twice about an hour apart. Temp dropped about 20 degrees in between if that makes a difference). Keep in mind this motor has a 3mm head gasket

1st:
139
145
150
140
138
147

2nd:
140
150
150
135
148
155

Nothing there seems enough to indicate a sticking valve or anything else for that matter.

What now?
 

figgie

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#23
As stupid as this might sound, have you checked the ignition wires to make sure you are not arcing to ground? Easiest way is to turn off all lights and check at night. See if there is any blue.

A valve would not be ticking that often. The ignition would as it would tick essentially every revolution since thanks to waste fire.

That crisp sharp clack on video sounds almost exactly like an ignition event (yes it is loud).

That is my best guess based on the video.

You said you took out the cams, did you visually inspect the valve springs?
 
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#24
As stupid as this might sound, have you checked the ignition wires to make sure you are not arcing to ground? Easiest way is to turn off all lights and check at night. See if there is any blue.

A valve would not be ticking that often. The ignition would as it would tick essentially every revolution since thanks to waste fire.

That crisp sharp clack on video sounds almost exactly like an ignition event (yes it is loud).

That is my best guess based on the video.

You said you took out the cams, did you visually inspect the valve springs?

Yes I did take a look at the valve springs. None of them were broken

I haven't checked the wires but they've been rearranged a bunch and they could have been cut at some point. The noise being gone when cold doesn't really match up with that guess but anything is possible at this point
 

figgie

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#25
Yes I did take a look at the valve springs. None of them were broken

I haven't checked the wires but they've been rearranged a bunch and they could have been cut at some point. The noise being gone when cold doesn't really match up with that guess but anything is possible at this point

Well there is nothing else at that level on the 7m head.the other thing to check is to see if any of the spark plugs are getting grounded via contaminents.
For giggle I would take the ignition caps of, take out spark plugs and then inspect them. See if there is any grounding paths especially on 3&4. Wipe them down and make sure you have no oil in the spark plug galleys.

edit: your first video is defienetly metal to metal (has a ring to it).

what oil do you use? (Weight wise).
 

Piratetip

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#26
Any chance you can remove the upper timing cover and inspect the timing components idler/tensioner/oil pump pulley.
Run the engine and watch in there for any abnormalities.
A timing light could help inspect the components by creating a strobe effect.
Or use a strobe light if you have one to see that way.

At this point we are all shooting in the dark.

The noise to me had 1 standout aspect.
Engine accel and decel vastly increased the intensity of the noise.
To me that points to components to that will be affected on a change rather than a static load (steady rpm)
 

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#27
Other than that.. I still think it sounds like rod or main bearing issue.
Though hard to tell from the video.
A lot easier to diagnose these things in person.
 
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#28
Well there is nothing else at that level on the 7m head.the other thing to check is to see if any of the spark plugs are getting grounded via contaminents.
For giggle I would take the ignition caps of, take out spark plugs and then inspect them. See if there is any grounding paths especially on 3&4. Wipe them down and make sure you have no oil in the spark plug galleys.

edit: your first video is defienetly metal to metal (has a ring to it).

what oil do you use? (Weight wise).
There is definetly a little bit of oil in some of the spark plug holes. I didnt think it would do anything so I just cleaned it up as best I could, but there is still some residual oil.

I use Valvoline VR1 20w-50
 
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#29
Any chance you can remove the upper timing cover and inspect the timing components idler/tensioner/oil pump pulley.
Run the engine and watch in there for any abnormalities.
A timing light could help inspect the components by creating a strobe effect.
Or use a strobe light if you have one to see that way.

At this point we are all shooting in the dark.

The noise to me had 1 standout aspect.
Engine accel and decel vastly increased the intensity of the noise.
To me that points to components to that will be affected on a change rather than a static load (steady rpm)

I've done cursory inspections of that area and nothing is really out of place. I'll check again whenever I go there tonight
 

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#30
Other than that.. I still think it sounds like rod or main bearing issue.
Though hard to tell from the video.
A lot easier to diagnose these things in person.

Agreed hence my question about the oil.

There is definetly a little bit of oil in some of the spark plug holes. I didnt think it would do anything so I just cleaned it up as best I could, but there is still some residual oil.

I use Valvoline VR1 20w-50
20w-50?

Way too thick. You might have spun a bearing because of it.
 

Piratetip

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#31
AGREED!

I run 0W-30 in most of my vehicles now, and love it. (Honda gets 5W-20 or 0W-20.)
The backwards mentality of using heavier oil makes no sense to me.
 
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#32
There is definetly a little bit of oil in some of the spark plug holes. I didnt think it would do anything so I just cleaned it up as best I could, but there is still some residual oil.

I use Valvoline VR1 20w-50
Eeeeeeek. That's not good, unless you had the bearings specifically clearances by a race shop with excessive clearance. Way too viscous for OEM spec 7M bearings.

AGREED!

I run 0W-30 in most of my vehicles now, and love it. (Honda gets 5W-20 or 0W-20.)
The backwards mentality of using heavier oil makes no sense to me.
Completely agreed. I use 0-30 or 0-40.

Removing EGR to "cool temps" and using thick oil to increase pressure (as indicated on the oil pressure gauge) are the two biggest irritations I have in the mk3 community. It used to be folks using MHGs with zero machine prep on the block, but that seems to have subsided in the last 3-5 years.

Hopefully this isn't a 7M that was killed due to incorrect oil.
 
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#35
RESOLVED:

The guy I bought the car from just admitted to me that it had rodknock in the past. Apparently he "forgot". The noise is definetly early rod bearing I've narrowed it down to that.

As for the whole oil thing, I read up on it as best I could and found alot of people having success with the valvoline vr1. I know everyone has their own opinions and I understand each sides points. I was damned if I did and damned if I didnt, but I had to pick one.

And just to add fuel to the oil fire, the guy I got it from used 0-40, always over full, and still got rodknock. I'm not saying it caused it by any means, but I havent found an oil that everyone likes.

Anyway, I got a new 7m from a buddy so I'll be swapping soon. Whenever I tear down Ill post pics up of the damage.
 
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Piratetip

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#36
RESOLVED:

The guy I bought the car from just admitted to me that it had rodknock in the past. Apparently he "forgot".
Haha. "Forgot"
Right.

That's an awfully convenient thing to forget.

Glad you figured it out.

On the oil weight topic, only run heavier weight if you know the rod / main bearings were clearanced wider than spec on purpose.
Otherwise if the clearances are in spec, run the recommend Toyota oil weight.

If heavier weight oil is needed to "cover" an oiling issue internally, there is something seriously wrong and needs to be addressed.
 

seoul4korea

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#37
Haha. "Forgot"
Right.

That's an awfully convenient thing to forget.

Glad you figured it out.

On the oil weight topic, only run heavier weight if you know the rod / main bearings were clearanced wider than spec on purpose.
Otherwise if the clearances are in spec, run the recommend Toyota oil weight.

If heavier weight oil is needed to "cover" an oiling issue internally, there is something seriously wrong and needs to be addressed.

FOR REALS hahaha, that guy didn't forget shit lol.
 

max-89supra(t)

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#38
Wish I saw this thread earlier to help out. My little brother bought a 92 turbo a few weeks ago and it had the exact same sounding knock. Ive had rod knock before but this sounded a lot like top end to me. After pulling the motor, it turned out to be a spun/destroyed rod bearing - cylinder #1.

The motor (7mgte) had a seemingly fresh rebuild. Mls headgasket, arp studs, braided oil pickup tube etc.
The oil seemed a bit thick to me, but the amount of silicone all over the oil pan was also suspicious. I have seen silicone destroy an engine before (cummins isx).

Going 2jz now, motor just showed up today.
 

max-89supra(t)

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#39
Took some pics of the damaged rod bearing but cant seem to attach them. Anyway its just a messed up bearing and a lot of metal in the oil pan. Good luck John, make sure you clean out the oil cooler etc from any metal left over, on mine the bearing material was all over the place.
 
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