1HZ ticking in certain RPM range (1 Viewer)

[lynchmob]

Ive got an odd noise coming from a 1HZ between 1600 and about 2300 RPM. It happens while driving or just raising the RPM into this range while parked. It doesnt seem to be related to engine load.

I recently adjusted the valves (almost all of them were too tight) and it made the noise before and after adjustment.
It has a new timing belt and idler as well as new injectors.

While driving, the noise sounds like a bad exhaust valve. While standing over the engine and revving its hard to tell where its coming from. It sounds like its in the head, but it also sounds like it could be from the area of he IP.

Some odd things to note:
While driving the noise sometimes goes away. If you power up to higher rpm in 5th and slow down into the offending range and drive normally sometimes it stops. It doesnt just go away under power. It seems to be tied to the rpm range.

While under the hood with the timing belt cover off the timing belt flutters significantly on the long run between the cam and IP.


Any input would be appreciated.

 

[lshobie]

I have it as well, and tons of other 1hz's have it, I wouldn't worry about it though. I will be replacing my injectors and doing a valve setup for the hell of it - but I am prettyy sure it won't fix it either. Only thing after that is the injection pump.

Check the aussie forums - they discuss this all the time = and there is no cure no matter how much money you throw at it. Bottom line is drive it and enjoy it.

Louis

 

[ThePookieBear]

Sounds like a 3FE...

 

[lynchmob]

I have it as well, and tons of other 1hz's have it, I wouldn't worry about it though.

Louis

Thanks Louis, I read a little on mud about some odd noise in 1HD and 1HZ but I wasnt convinced it was the same thing. Ill have to dig into some other forums (too many forums)

From the little I read Im not sure its the same. The noise Im getting is quite loud. So loud that if it was a bad valve the engine would run poorly (which it doesnt) . Its hard to describe how loud it is, but id say as loud as a significant rod knock.

Ill read more, but its not the kind of noise that I would let go.

 

[Radd Cruisers]

This sounds like valve noise.

The valves must be done when the engine is fully cold. We had one in the shop with tight valves, and it sounded nasty. The noise was most apparent when fully warm (after a decent run on the highway) and at certain RPM ranges and loads.

I'd suggest checking the valves again...


~John

 

[lynchmob]

This sounds like valve noise.

The valves must be done when the engine is fully cold. We had one in the shop with tight valves, and it sounded nasty. The noise was most apparent when fully warm (after a decent run on the highway) and at certain RPM ranges and loads.

I'd suggest checking the valves again...

~John

Thanks John, The engine was stone cold when I did it (60F or so). Two are still just a little below the tight spec and I will do those when I get the shims. Currently it doesnt seem to matter if its fully warmed up or not.

When I did the adjustment several of the valve shims had almost no clearance (all intake side I think). Ill check them all again now that its been driven a while after adjustment. Going to check compression again too.

 

[gifu]

I've heard that if the main bearings are on their way out, they can allow the piston to just barely kiss the valve(s). I'm not sure I believe it, but this was talked about on a couple of the other forums.

there were also unrelated occurrences where upgrading to ACL bearings made the ticking noise go away.

 

[roscoFJ73]

My HZJ75 does something similar,but only under a light load ,at 1800-2100.It disappears under heavy acceleration and cannot be heard free revving it in neutral
Its a tick that is regular and sometimes irregular and each tick sounds vaguely like gas escaping.
I have noticed some discoloring around the manifold gasket at number 6 exhaust port and wondered if it was leaking.
Ill get around to checking it one day but if it was leaking I would probably smell it and it would have gotten worse by now.

I dont think the tick was there when I bought the vehicle at 190000k but started after the 200000k mark

I have had the BEB replaced with ACL(old ones were like new) and the valves done(tight because they hadnt been done) to no avail.

There is a long thread somewhere on the 4WD Action forum and some call the noise "crank flex" which they got from Toyota
According to Toyota Australia it is caused by a block that is not perfectly aligned.
Thats their excuse and they will not replace the engine as it doesnt hurt the longevity.

I cant get my head around how a crankshaft can flex enough to make a noise and not self destruct.

I dont really worry about the noise any more but I would love to know the cause

 

[lynchmob]

I just cant get myself to dismiss this noise. Im not really sure its the same thing that so many others seem to post about. Its nothing like a ticking 2F or 3F with valve noise. Its troubling to the point where I may pull the head if some other things dont affect it. Someone suggested it may even be a precup.

 

[roscoFJ73]

Someone suggested it may even be a precup.

That has been at the back of my mind but an engine reconditioner I asked said they sound different
I can hear it well if I bounce the noise off a concrete wall on the freeway

 

[tmarx]

I have convinced myself that it is my exhaust resonator

 

[Adam B]

My 1HD-T does the same thing (similar, anyway) and I've been wondering if it was the beginnings of rod knock. I've had a 7M-GE so rod knock is always in the back of my mind. My rod bearings are only 2 years old (40,000 km), done by ATEB before I got the truck. There's no change between 5W30 Synthetic and 15W40 Synthetic.

It's most noticable when I'm going slowly up a bridge and can hear the noise reflect off the concrete divider. I'm really not sure if it's worse now but the weather is nice so I'm driving with the window open and can really hear it. Seems worse than last summer. I can't hear it below 1200rpm and can't hear it above 1800rpm but my exhaust is pretty loud above that so I don't know if it actually goes away.

Mine is only evident under load. Revving in neutral doesn't make the noise.

No exhaust leaks that I know of, but I can't rule out one at the manifold.

It really doesn't sound like top end noise to me. I've also had a 22R-E with very noisy valves and this is very different.

Oh well. Might be the same as others, might not.

 

[mac]

I know this is an old post but i just stumbled across it. I had a nagging noise from my 1HD-T that I couldn't rectify through valve adjustments, etc. It turned out to be an oil pump gear wandering back and forth on the shaft and striking the timing cover. Toyota doesn't give a spec for end play on the oil pump gear, only lateral play so I never measured it when I put the engine together. Caused me a ton of frustration and time.

 

[roscoFJ73]

Pete,can you give us a description of the noise. I still have a faint ticking in the 1800-2100 rpm range.
Ive snapped off a bolt in the timing case,so when I get the energy to strip it down I may check the pump

 

[lynchmob]

I know this is an old post but i just stumbled across it. I had a nagging noise from my 1HD-T that I couldn't rectify through valve adjustments, etc. It turned out to be an oil pump gear wandering back and forth on the shaft and striking the timing cover. Toyota doesn't give a spec for end play on the oil pump gear, only lateral play so I never measured it when I put the engine together. Caused me a ton of frustration and time.

I pulled the timing cover as part of the witch hunt. There was no indication of contact anywhere. The only thing that I would have done if I had the parts was replace the idler gear shaft and perhaps the idler gear. The design of that gear on the hz/hd seems to lend itself to a lot of axial stress. It was worn but still at the high end of the spec for backlash.

 

[metaljong]

Check the aussie forums - they discuss this all the time = and there is no cure no matter how much money you throw at it.

Long thread on lcool if you're a member there:

LCOOL.org :: Log in

 

[lynchmob]

we finally let it go. The engine that prompted me to start this thread is still going well. It has a few thousand miles on it since then.

 

[Volcano cruiser]

we finally let it go. The engine that prompted me to start this thread is still going well. It has a few thousand miles on it since then.

So no one has tracked the source of this noise down yet? I am now officially slightly worried. This could escalate to mildly worried once the 1HZ goes into my rig this week and IF I start hearing stuff other than my normal 30 year old car body creaks.
Thanks.

 

[lshobie]

Don't worry about it, many if not most higher km 1HZ's do it - even after a rebuild. Some say it is the pulsing of the injector lines or something like that as well.

I have a clicking but it is the r151 tranny

 

[roscoFJ73]

So no one has tracked the source of this noise down yet? I am now officially slightly worried. This could escalate to mildly worried once the 1HZ goes into my rig this week and IF I start hearing stuff other than my normal 30 year old car body creaks.
Thanks.

Forget about it. Mine has been doing it for 50000 klms and it has never gotten any worse.
Its so quiet most people cant hear it
Toyota Australia wont even fix it under warraty because they say it cant be fixed and they dont really seem to know what it is anyway.
Of course this all depends on what the ticking is. You could check the BEB but its rare for a 1HZ to have problems there.