See video: https://youtu.be/YVRDqrHCh3s?t=116 (you cant hear it from the cabin very well on this video, though it is pretty obvious in real life)

Hi all

I've got a horrible grinding noise coming from the head of the engine at around 2000 rpm. It carries on until above 3000 rpm at which point its not so bad, or you're on full throttle and cant hear it over induction sound. It sounds like something hitting something. You can hear a light grind / buzz when cruising along on part throttle. Not sure what in the head could be making the sound.

Using a stethoscope you can feel it coming from the front of the head. The only other component which sounds loud through the stethoscope is the belt tensioner. I will be taking the belt off shortly to factor out any belt driven accessories as the cause.

The previous owner had a new TCT and chain put on 6k miles ago. I believe the sound has slowly gotten worse over my ownership of 6k miles.

Car still revs to 9k happily. Problem is at its worst when using around 2.5k rpm when setting off in 1st or reversing.

I'm going to take the valve cover off and have a look inside but doubt I have the ability to diagnose anything visually.

Any ideas? Weeks of scouring the internet and I haven't found anyone with the same issue.

Cheers

 

Sounds similar to when my valve adjustment nuts came loose, so I would suggest a valve adjustment if you haven't done one already. They are very important for this car regardless.

 

Thanks Soviet.

The car is booked in for the valve adjustment and to investigate the rattle on Friday. I hope it is something as simple as a slightly loose bolt.

 

"Booked in" meaning some shop is doing the work? The valves should be on the loose end of the spec as they tighten in use. "Somewhere in range" is certainly in spec though.

-- Chuck

 

Yes, the local Honda dealership are carrying out the work. There aren't really any specialist garages around here so they will have to do.

£100 flat fee for the valve adjustment, that isn't so bad. Part of me thinks it wont make any difference though. But, the issue may be more obvious to a trained eye when the valve cover is off, assuming the mechanic has seen a few valve trains before.

 

Just got the car back from Honda. They adjusted the valve clearances, noting that 1st cylinder were all tight, 2nd cylinder loose and tight, 3rd ok and 4th one valve out of 4 tight.

The rattle has pretty much gone now. Its about 90% better. So I'm happy with that.

Would probably have been worth checking the valves first, before the 1st garage suggested checking the big end bearings as they thought it was a knocking noise! Waste of a few hundred quid there.

 

I had the valves adjusted on Friday, a few were loose a few tight. The engine did sound better for a a day or two but now is back to making the same noise above 2.2k rpm or so.

I'm not sure what to do. The gearbox is very loud especially in 3rd gear at high rpm, so I was going to get a new gearbox and clutch put in. The engine noise troubles me and I want to solve that before dropping more money into the car.

All of the easy options have been explored. There must be something wrong with the cylinder head. There doesn't seem to be a garage in the UK with the expertise to diagnose what the issue is.

 

Maybe whoever adjusted the valves left a jam nut loose?