I am stumped...

I can'f figure out what this knocking sound is when I do fast right hand turns. Only when doing fast rights, left makes no sound and slow rights make no sound either.

The knocking is a knock knock knock, maybe 3 knocks per second? I can feel it in the brake pedal so I thought maybe it's something knocking against the firewall. Investigation has come up with the following:

1) The exhaust is on tight, all clamps and mounts are in A1 condition and don't move at all. I can't see it being that

2) engine steadies on both sides (I have an 1098) are in A1. I replaced it all not long ago and they don't move a inch. Grabbing the engine and rocking it rocks the whole car

3) I just spent the weekend under the car on the swivel hubs, brakes etc. No change in knocking sound, it's still knocks. I have all new rubbers under the car now too so I can't see it being that

4) I thought it was maybe the electric fuel pump but that's mounted at the back and it's on tight. Can't see it being that.

5) I looked at the dellorto 45 mounted on a redline. Now there is clearance (Doc kicked up the intake a few degrees on both sides and used a BFH to slightly modify the firewall. I can fit my fingers between the Lynx ramflo and the firewall so I can't see the engine swaying that much?? could it possibly be that? how come I've never had this problem for 2 years until now?

6) I can't see anything loose or needing attention gearbox side. Mounts are good, bolts are all in, rod change is stable (as it can be)

My only thoughts could be that my timing chain is loose currently. Can that be the sound? as I do a fast right the chain hits against the cover or something making a knocking nose? but If this is true I think it will just be a loud scrubbing noise as apposed to a knocking...

Any ideas guys? I really think it's an anxillary and not internal engine as the engine is running VERY mean currently (See you at the dyno day )

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Lillee - 1969 Morris Mini K

you mentioned rod change. It is a rod change gearbox with pot joints ??????

I would be looking at either the pot joint or the CV joint in that a ball may be beginning to run oval or the engine mount is broken and allowing the bottom of the engine to move and placing strain on the pot joint structure.

Thanks Mike, I have pot joints that I regreased and rebooted not too long ago. CVs are brand new.

Hmm i thought it may be the engine mounts as I have no idea their condition. Why would great strain on pot joints do this? and why is it only when going right?

Maybe it is the engine mounts that is allowing the engine to sway left when doing a right hand turn and the dellort hits the firwall?

I am pretty sure the sound is something knocking against the firewall, but as car as I can see fron top and bottom the engine bay, I can't find anything that would do this... I need a home car hoist

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Lillee - 1969 Morris Mini K

Hi Chong,

That sounds like a wheel bearing.
Most likely one of the left bearings.
I have the same problem with my MGB at the moment
,it has the left rear bearing seal leaking.

Felix

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1966 mustang coupe 289 auto
1970 mgb roadster auto
1970 cooper S mk2
1976 mini S
1964 wolseley 24/80
http://s160.photobucket.com/albums/t173/1966mini/

Easy to check - jack the suspect side of the car - secure it with a jack stand and then jack up the ailing end of the motor using a block of wood between the jack and the gearbox. Dont jack too far as you will pop the engine mount (even if it wasn't previously broken) as the rubber does perish reasonably quickly.

Why - the pot joint - well the balls dont fit too far into the steel joint canister and with a lateral gravity load and an engine moving (even millimetres) the balls begin to bang around the edge.

Since you have recently rebooted and regreased the pot joints, just feel around the boot to re-assure yourself that there isnt a ball in the boot that has dropped out at some point. I have, in the past had to have three goes to get a pot joint in with out dropping a ball.

Felix: Brand new timkin tapered roller bearings both sides... Actually swivel hubs are totally brand new/reconditioned by Doc Can't be anything there

Hmm will check the pot joint and report back...

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Lillee - 1969 Morris Mini K

discs or drums ?????

It's not the passenger knocking his head on the door trying to get out in those fast right hand turns is it 68Delux????

did you take the toolbox out of the boot after your infamous spin up the central coast going to Kazjim's?
KB

A mate had this exact problem in his Astina recently. Turned out to be the starter motor. On Astinas the starter springs back out of the way of the flywheel but this one was re-buit without the spring. Click-click-click as the pinion bounced off the flywheel turning right. His did it when parked on a hill with passenger side lower than driver's and wheels pointing straight ahead.

Yours could have a similar problem. If the starter has a return spring that is a bit slack, then under hard rights the weight of the pinion assembly may be stronger than the spring and bounce it goes off the flywheel.

Wouldn't be able to feel it through the brake pedal though.... Hmmm???

M

Great suggestions guys, thanks for the input.

Cooper S disc brake front end, fully rebuilt, tight ball joints, new bearings, new CVs etc...

No no passengers Smokie

No toolbox either Kev... I won't ever get rid of my 360 Chong title will I?

Interesting Mokesta... but I have a NOS starter which I am sure has a spring and is not slack. I can check but I doubt it as I have had the starter for more than 2 years without problems...

Dun worry I'll take it to the good Doctor for a diagnosis I'm booking an appointment now

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Lillee - 1969 Morris Mini K

Steering rack to firewall u-bolts tight?

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Curly
'64 Cooper 'S' (Group Nb spec)
'67 Mini Marcos GT www.mm7056.wordpress.com

Yes. Recently did this to drop the steering wheel via lowering bracket.

Will double check all these things though... Gee never thought about any of these! you guys rock!

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Lillee - 1969 Morris Mini K

Mike Byron scores 10 points!

When changing the bottom arm bushes, the races must have been pulled too far out of the pots and a ball fell out on the right hand side!

Popped the top ball joint and popped the ball back in, abit of grease and away I went, no more knocking !!!

Now the next problem, my timing chain is so loose it's knocking on the side of the cover radiator out time I think, fun!

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Lillee - 1969 Morris Mini K

On the latest drama, are you sure it is the timing chain?

I had a rattle that slowed/sped with engine speed (more or less) and stopped at certain revs. turned out to be the bottom pulley - the rubber splits and cracks and it moves in opposition to the rest of the pulley.

Doc should be able to give you a consult, probably even bulk bill it to medicare!
KB