Rattle at 2000rpm and 3000rpm only

m1dg3 · April 30, 2018, 12:01

Hello everyone. Long time listener, first time caller.

I wonder if anyone has heard a noise like this before: https://www.youtube.com/watch?v=7mGIFBvRk6I

The rattle only occurs when the car is in gear and moving and only at 2000rpm and 3000rpm, not between. Seems to be in all gears. It is quite loud - that clip was taken from the cabin with the roof down and the rattle is much louder than the engine or the wind noise (although I was only driving at about 25mph).

It started making the noise after a trip over to the Brecon Beacons from Cheltenham and back so it had done a couple of hundred miles that day. When I checked the oil it was very low (hardly troubling the bottom of the dipstick) so I've been thinking it is bottom end but from watching clips of other bottom end problems it really doesn't sound like those. It doesn't have that metallic knocking / sewing machine sound to it, it's more like a stone stuck in the tyre turned up to 11. I also have had a heat shield rattle and it doesn't sound quite like that either although I appreciate that depending on which bits are loose it may sound different.

I've been tearing my hair out and the nearest I can find is something to do with the valve train or an exhaust manifold leak. Can anyone recommend the best way to diagnose it? I'm relatively handy with the spanners but would like to eliminate things in a logical order.

Thanks folks if you've managed to get this far as I'm sure most members have got 'engine noise question fatigue' by now!

Ardent · April 30, 2018, 12:53

Hello and welcome.

Sorry cannot help with the sound.

Ardent · April 30, 2018, 12:53

Where arw you based

Carolyn · April 30, 2018, 13:15

Very low oil. Were you giving it some beans around long bends? If you've been hooning with low oil, chances are you've done damage.

If so, it does rather sound like a rod bearing. Typical rev range for it to show up. A really bad rod bearing failure CAN result in a piston tapping on the head. That's unusual.

It's extremely difficult to discern rattles and noises on Youtube vids, though.

The only way to know is to examine a few things. You can drop the sump easily enough, though breaking the glue bond is a pain, then you can pull a couple of bearing caps and see what the shells look like.

Also, if it's struggled for oil at the top end, the last pressurised bit in the system is the chain tensioner. Hard to examine, but easy to replace. If the tensioner has suffered, then the chain may have suffered too.

You can pull the timing cover and check for a loose chain.

No substitute for having a look-see, I'm afraid,

m1dg3 · April 30, 2018, 13:47

Thanks folks.

I'm in Gloucestershire - I'll amend my profile.

Carolyn, thanks for your reply. Just to clarify, it isn't a rev range that it rattles at - only at 2000rpm and 3000rpm but not 2100, 2200, etc. That made me think it was something resonating, like a heat shield. Also seems strange it is only when actually driving.

If dropping the sump and inspecting the bearings is the best thing to try first then I'm happy to do that although whipping the rocker cover off and checking the chain sounds more appealing from a time perspective. I suppose what I wanted was a bit of a clue as to where to start so thank you very much for that.

Carolyn · April 30, 2018, 14:30

Ah a resonance. That's different. Could be a loose baffle in the exhaust..

That WILL drive you nuts until you find it.

If it's running OK, don't open the engine up on my say-so!

m1dg3 · April 30, 2018, 15:31

Don't worry, I'm old enough and ugly enough to take responsibility for whatever I do to my engine! I'm just grateful for the opinions.

What's really frustrating is that it doesn't make the noise when stationary so I can't push bits of the heat shield or exhaust to see if the sound changes. I guess I could remove the heat shields completely to test it.

MisterK · April 30, 2018, 16:28

I've got a loose baffle in my TTE exhaust. It rattles at 2000 rpm whether moving or stationery & is worse when cold...when hot things have expanded and the noise reduces so I'm living with it for now. Your noise doesn't sound the same as it is when only moving. Mine is worse when revving engine slowly past 2k when stationery - at 2.3k it disappears again so it's a resonance rattle. Hope this helps.

m1tch · April 30, 2018, 16:48

Its the heat shield on the manifold to cat pipe, they are tack welded on as standard which then rusts and fails, its the same on mine - jubaliee clip fixes the rattle

m1dg3 · April 30, 2018, 17:31

MisterK - exactly my thoughts. I can't see how it would only rattle when moving. I have had a heat shield rattle before and it sounds more like a drink can being dragged behind the car.

m1tch - thanks for the suggestion. A jubilee clip has got to be worth a go given how easy it is to try.

m1tch · May 1, 2018, 07:39

Quote from: m1dg3 on April 30, 2018, 17:31
MisterK - exactly my thoughts. I can't see how it would only rattle when moving. I have had a heat shield rattle before and it sounds more like a drink can being dragged behind the car.

m1tch - thanks for the suggestion. A jubilee clip has got to be worth a go given how easy it is to try.

If you look under the car where the exhaust goes into the main cat you should be able to work out if that is causing the issue - found that mine was where the 2 heat shields were clattering together.

The Other Stu · May 1, 2018, 12:41

Quote from: m1tch on April 30, 2018, 16:48
Its the heat shield on the manifold to cat pipe, they are tack welded on as standard which then rusts and fails, its the same on mine - jubaliee clip fixes the rattle

I'm surprised it took that long!

Sounds like classic rattle. Mine did it when I first bought it. Drove me up the wall!

MisterK · May 23, 2019, 19:44

Ok, so it's a year on & I've eventually got around to sorting the rattle coming from my TTE exhaust. It got to the point where I could stand it no more. When at Rogue a couple of weeks ago I had a chat with Matt about the problem & it was agreed that the solution would be to remove the exhaust, cut the silencer open and identify the issue & hopefully resolve it.

The exhaust eventually came off after Matt wrestled with the 3 amigos and he managed to get the studs out without snapping them. We decided to cut out a panel from the rear of the silencer to see what we would be up against inside.

Suprisingly, there is not a lot inside the box apart from the pipe coming in and the 2 exit pipes, plus what looks like lots of screwed up piles of fibreglass loft insulation.

The fibreglass bits were removed and we discovered that the inside of the box where the exit pipes fed through the side of the silencer were not actually welded - there were welds on the outside obviously. This meant that the pipes were loose and rattled against the side of the silencer box, especially when cold. Matt wleded up these joints, plus the inlet pipe joint and everything then appeared solid.

He then welded back the panel which had been removed and I must admit he did a fabulous job...we left out the fibreglass as we couldn't see that it was performing much of a function. The exhaust and cat were re-attached with new gaskets and nappies etc fitted back. Exhaust tested and no leaks I was a happy bunny.

The car now sounds fantastic... maybe a little bit louder and crisper than before, but I like it and NO rattles.

I would thoroughly recommend Rogue and Matt was a pleasure to do business with.

MisterK · May 23, 2019, 19:46

Silencer after opening

MisterK · May 23, 2019, 19:47

After fixing issue and welding panel back on.

shnazzle · May 23, 2019, 20:45

Christ... That's not the quality of work I expected in a Remus.

Thanks for posting those pics. I've always wondered what it was like

m1tch · June 19, 2019, 07:13

Hmm glad I sold my TTE now looking at that exhaust routing and restriction!

StuC · June 20, 2019, 00:55

@MisterK interesting post mate.
I am taking Lily to Rogue on Monday for a service, with Steve out of action. Nice to get another trusted opinion of them.

I am glad the rattle saga is finally over!!!

shnazzle · June 20, 2019, 10:17

Is the rattle saga also over for @m1dg3?
Or did I miss that?
Damn rattles. Enough to drive one up the wal

frogger · June 20, 2019, 12:29

My TTE has just developed the same rattle!
:`( it is rather annoying!!!

How much did the work cost?

I can't make out in the images what was actually done to resolve it.

MisterK · June 20, 2019, 22:49

Quote from: frogger on June 20, 2019, 12:29My TTE has just developed the same rattle!
:`( it is rather annoying!!!

How much did the work cost?

I can't make out in the images what was actually done to resolve it.

The rattle was as a result of the internal welds for the 2 exit pipes working loose inside the box. Matt removed the whole exhaust and then cut out a panel from the whole of the silencer which gave access to all of the internals. Inside the box was loads of 'loft insulation' in 4" sections. This was removed and the loose welds were re-welded and the removed panel welded back on. It now sounds fantastic with no rattles. Costs..£200 ish, but I think it was well worth it.....the TTE exhaust should last for many years to come & is already 14 years old. Its the best exhaust for the Roadster in my opinion. Matt at Rogue did a fab job & I'm very happy.

shnazzle · June 20, 2019, 23:01

Quote from: MisterK on June 20, 2019, 22:49
Quote from: frogger on June 20, 2019, 12:29My TTE has just developed the same rattle!
:`( it is rather annoying!!!

How much did the work cost?

I can't make out in the images what was actually done to resolve it.

The rattle was as a result of the internal welds for the 2 exit pipes working loose inside the box. Matt removed the whole exhaust and then cut out a panel from the whole of the silencer which gave access to all of the internals. Inside the box was loads of 'loft insulation' in 4" sections. This was removed and the loose welds were re-welded and the removed panel welded back on. It now sounds fantastic with no rattles. Costs..£200 ish, but I think it was well worth it.....the TTE exhaust should last for many years to come & is already 14 years old. Its the best exhaust for the Roadster in my opinion. Matt at Rogue did a fab job & I'm very happy.

Mark, out of curiosity, are those internal pipes perforated and wrapped in essentially wire wool? Or are they solid pipes underneath the wrapping?

MisterK · June 20, 2019, 23:10

Now you're asking

The internal pipes are definitely covered in wire wool but whether the pipes underneath are perforated, I couldn't say ... I didn't pull the wire wool off. The sound is slightly louder with no 'loft insulation' but sounds better in my opinion with just the wire wool around the pipes. Hope that helps.