33 replies to this topic

[jakejakejake1]

I know what you're thinking! Its the exhaust knocking on the bulkhead due to worn engine steady bushes

Yeah well I thought that too at first, but the engine steady bushes were only replaced last week (coincidence?) and I cannot move the engine by hand, although when rocking the car in 1st there is a bit of movement (+/- 5mm or so), and the exhaust has plenty of clearance with the bulkhead.

The knocking doesn't occur when the clutch is down, and doesn't happen when acceleration, and I cant replicate it by rocking the car in gear, and it doesn't knock when pulling away (in 1st or reverse).

I have had a look in the engine bay but there doesn't seem to be much close to the bulkhead that can move so I'm a little confused at what it could be.

Any suggestions?

Cheers, Jake

[jaydee]

Open the bonnet and turn the steering wheel full lock side by side, is the engine moving?

[[email protected]]

It may be the engine steady mount on the bulkhead, they are only spot welded on and can work loose. Bit of a pain! I fitted an ultimate engine steady kit and it solved the knocking. When I rocked the engine I could see the plate moving. might be worth a look.

[jakejakejake1]

Ok, well the steady mount on the bulkhead seems fine.
The engine moves slightly when reaching the last 20-30 degrees of lock in either direction, but only by a small amount (maybe 5mm or so, but the knocking happens regardless of direction of travel)

Also some more background information that could be on interest.
The knocking started after I jacked up the driver side front to fit the exhaust to gearbox mount, and also the suspension seems softer on the driver side front wheel (which left the floor when jacked up).
I have never noticed the suspension being so soft before, when rocking the car there is noticeable deflection, whereas the other three corners are pretty rock solid (old crappy cones that need to be changed).

So could I have dislodged something while lifting the car up, and this is causing soft suspension and a knocking noise? As the noise seems to be coming from in front of the steering column, although we all know how hard it is to pin point knocking noises in a mini!

Cheers, Jake

[MrBounce]

Check your front subfame rear mounts. And the condition of your subframe. Someone I once knew had a similar noise and his subframe turned out to be cracked...

[jaydee]

Sounds like the subframe to floor mounting is gone..

Edited by jaydee, 21 August 2012 - 07:40 PM.

[Cooperman]

Check sub-frame mountings. Best to fit solid ones anyway.
Check the damper bushes, although it's unlikely that that's the problem.
Check the engine mountings and the lower steady bushes if a lower steady is fitted.

[jakejakejake1]

Well I had a look after jacking the car up, and both the rear mounts look ok - their not brand new condition but they don't look overly compressed, cracked or otherwise out of the ordinary as far as i can tell, all the bolt/studs/nuts look to be fine and unmoved.

The bottom steady bar from the gearbox to the front of the car has perished rubbers, but this is nothing new so i will replace these when possible but don't suspect them as the cause of the knocking.

But an interesting note - after lowering the car back down, when I first was driving the car the knocking had stopped, I even tried replicating the conditions that made the knocking worst, but nothing. That was until after a while it came back again, but doesn't seem as bad as before - weather this is a placebo effect due to the period of no-knocking I don't know.

[silver_toes]

Sounds like the subframe to floor mounting is gone..

Is this the mounting you can see in the passengers footwell ?

Sorry for the hijack, but i have exactly the same issue

I've checked the engine mountings and they're rock solid. Couldn't move the engine a mm whilst swinging on it. I suspect now my issue may be subframe related

[jaydee]

Yes the attach to the subframe and to the floor pan by two retaining bolts connected together with a strap as you can see in the footwell.
They usually look fine when they fail because they're two metal plates (one bolts to the floor, the other to the subframe) connected together by a thick rubber part, you cant see when the rubber part disconnects from one of the two plates unless you poke the subframe with a pry bar.

[KSTANDSTEVE]

Anyone got a pic of this rear subframe mount?

Have a knock myself and this is something I havent checked.

[dklawson]

I cannot add anything relative to checking subframe mounts and it sounds like you have already ruled out engine steadies. I have a different item for you to check instead.

Jack the car up and support the front on stands (both wheels off the ground). Turn the steering so it is all the way to lock. Grab the rack (where the inner joint is hidden behind the gator). Push and pull on the rack to see if it moves and you can create a click or clunk. Check both ends of the rack. Turn the steering to the other lock and repeat your test. If you find at either lock condition you can make a click or clunk at either end of the rack the bushings inside the steering rack may have deteriorated. That can cause a much louder clunk inside the car when you are accelerating, decelerating, or hit bumps in the road.

[Spitz]

Solid ones
http://www.minispare...lassic/subframe mount.aspx|Back to search

Factory rubber ones ( not a great picture
http://www.minispare...lassic/subframe mounts.aspx|Back to search

[Equinox_Monty]

Jake, have you manged to resolve the problem with the knocking yet?

I'm interested to know what sorts it as I have virtually exactly the same problem.
The top engine steady bar on mine is adjustable due to the bolt having sheared off at some point and the bar has been extended to reach the front hole.
I have quite a bit of movement when pushing the engine from the top which does appear to allow the exhaust joint to bang on the floor pan.
Just by rocking the engine by hand, I can't replicate the knock though.
I need to check both engine mounts when I have good light to rule out those, but I am trying to plan the next thing to look at if the mounts are OK.
I have adjusted the top steady to allow the engine to tilt back towards the bulkhead which then gives loads of clearance for the exhaust. The knocking doesn't happen when set like this but there is a horrible grinding sounds coming from the drivetrain when its the engine position is set like this.

I just can't find a happy medium when neither problems are evident and my hair is getting more and more grey by the day!
Any help would be so appreciated.

[jakejakejake1]

Unfortunately I have had no luck with this, although my engine doesn't move at all my hand (well maybe a few mm, what would be expected on new steady bushes)
But I have been able to replicate the noise now when stationary, and putting the car into 4th, and getting someone to push the car.

The noise sounds like it is coming from the clutch end of the engine bay, to the left of the engine, so possibly the top subframe mount? I'm unsure as I'm not entirely sure what around that area could be causing the noise.