11 replies to this topic

[20Drift]

Hi all,

 

Had an issue which has been driving me mad trying to find, just looking for some pointers!

 

Mini is a 1986 Mini Mayfair 998cc.

 

When coming off the accelerator sharply, I get a very loud knocking sound which sounds like it's coming from the firewall. I've been doing some hunting and checked the following...

• Subframe mountings to the footwell are not cracked - they've had reinforcement plates welded before. Using a pry bar on the underside gives no movement at all (rubber mounts being used)
• Subframe mountings to the top of the strut towers under the bonnet are solid

 

Whilst I was jacking the car up from the front teardrop mount, I noticed the bushing looks a bit worse for wear:

 

When jacking it up, that bush deflected a fair bit more than the passenger side. I've also noted the front tie rod bushes are cracking, so I'm wondering if this is the cause? 

 

It was booked in at the garage before corona kicked in, so not sure when it'll go down to have a look at properly. I want to get it over an inspection pit and have someone look under it when it knocks to see if something obvious is moving! Any pointers in the mean time will be much appreciated.

[sonscar]

Grab hold of the rocker cover and rock the engine,see if it moves.Put it in gear Not Running and rock the car back and forwards to see if the engine moves.!Steve..

[alex-95]

More than likely the engine steady bushes are worn or the bracket has snapped. how much does the engine move when you push it back and forwards? it could be the carb hitting on the bulkhead which may have bent the jet.

[20Drift]

Sorry should have added - tried the rocker cover Trick but the engine barely moves. Definitely not enough to hit the carb on the bulkhead

[cal844]

Under load the engine moves much more, personally change both stabilizer bushes

[20Drift]

Grab hold of the rocker cover and rock the engine,see if it moves.Put it in gear Not Running and rock the car back and forwards to see if the engine moves.!Steve..

Interesting hadn’t thought of this. Will have a check later

[andyapanel]

+1 for top engine steady

[timmy850]

I had a similar problem on mine and it went away after I changed the lower arm suspension bushes which had deteriorated. Worth checking the lower arm and tie bar bushes 

[20Drift]

Just an update for you all... couldn’t track down the issue with the car on jack stands or ramps, so took it down to the local garage as they have an inspection pit.

They found when letting off the clutch, the rear passenger side mount for the front subframe is coming away from the body. Looks like the rubber has come away from the metal. Currently got two new rear mounts on order and two front teardrops as well. Hopefully that’ll sort it!

Thanks for all the tips!

Edited by 20Drift, 02 June 2020 - 07:42 PM.

[Algordo1100]

That's good it's getting sorted.

It will certainly drive better too with the subframe held on properly! :)

[MiniMadRacer]

Side issue.. dont jack the car up under the tie rod bracket,,, sooner or later you will bend that tie rod

[cal844]

Side issue.. dont jack the car up under the tie rod bracket,,, sooner or later you will bend that tie rod

I do, however only if I really have to, if my jack wint go under the subframe to my preferred lift point. I do however have two Jack's so life is slightly easier