10 replies to this topic

[pip]

Model: Mini Flame
Year: 1990
Description of problem (please be as in depth as possible): Car makes a knocking noise when driving, doesn't make the noise at idle or when revving in neutral and also stops when you take your foot off the acclerator, the car has also suffered a loss in power since the noise started, apologies for starting a new thread on the same subject but my other post seems to be being ignored and I need to get it sorted ASAP

Any ideas?

[lawnmowercrap]

Does it sound like an engine knock or like something is hitting the body?

This is the first thing you need to decipher before we can help you.

If its an engine knock it can be anything from timing to bottom ends.

If its something hitting the body it could be poor engine mounts, worn steering / suspension components or the exhaust flapping about.


Lee

[pip]

Does it sound like an engine knock or like something is hitting the body?

This is the first thing you need to decipher before we can help you.

If its an engine knock it can be anything from timing to bottom ends.

If its something hitting the body it could be poor engine mounts, worn steering / suspension components or the exhaust flapping about.


Lee

The noise has come on all of a sudden whilst driving at town speeds yesterday, and is definately coming from the front of the car and given that it's caused a loss of power and goes away when you let off the acclearator then i'd say it is an engine knock but like I say it is fine idling it's only when driving.

[Neil7744]

id be tempted to get the car on jack's and check for play in wheels, bearings and joints first. Id also do what is mentiponed above and check lower mounts and engine steady for wear first.

[lawnmowercrap]

Does it do it from both cold and hot? Or just one?

Grab the oil filler cap and rock the engine forwards and backwards. The engine shouldnt really move at all. If it does, new engine steady and gearbox bushes are required.

Check all of the subframe mounting bushes. If any are split, replace them.

Check the tear drop mounts as these cause excessive knocking on pulloff and when changine gear.

Check the tie bars for split bushes.

Jack the front end of the car up and wobble the wheels side to side and up and down. There should be NO play at all. Play here can be either wheel bearing, track rod end, steering arms, ball joints etc.

Whilst its jacked up, check the shock absorbers and bump stops are ok.


If all this is ok, look all around the front end of the car for something that could be loose and causing the knocking.

If that is also ok then you need to start to look at your engine.


Is there any oil in it? When was it last serviced? Is the carb hitting the bulkhead? Etc.


If you cant replicate the noise when its in neutral then its unlikely to be an engine fault, more of a gearbox / driveshaft fault.

If however when revving the car in neutral you can replicate it then get someone to rev it and use a screwdriver and place it on the head, block, gearbox, timing cover etc. and put your ear on the other end. You should blatanley hear the knocking.


When you've done all this, get back to us.


Lee

Edited by lawnmowercrap, 25 February 2010 - 07:30 PM.

[pip]

Ok, thanks for the replies, i'll work through the list tomorrow and get back to you

[samski]

engine mounts change all of them should sort it out,

[pip]

I really think it's coming from the engin/gearbox/driveshaft/clutch, came on all of sudden, loss off power etc etc

[sonikk4]

I really think it's coming from the engin/gearbox/driveshaft/clutch, came on all of sudden, loss off power etc etc

You say it only happens when under load, its possible your big ends have gone if its a heavy continuous knocking noise or something else internal.
You may not hear this noise when no load is applied, idling etc.

I know minis have a habit of knocking out their engine steadies but for sudden power loss under load would point to something internal.

Sorry this is not good news but if your engine steadies are good and your drive shafts, cv joints are fine then it could be something a lot more serious. Possibly gearbox.

Drop your engine oil and have a look at the drain plug for any metallic debris as this will show if there is any sign of internal distress.

[pip]

Dropped it off at the garage this morning, will report back next week

[pip]

Had a compression test done, head gasket. Thanks for the help, especially those who suggested engine mounts etc