Judder on take off

[triumphelan]

I have a judder when pulling away from standstill at slow speeds ,not when I make a quick getaway,once moving the car runs sweet.I can feel it through the clutch pedal but only at initial take off
.To try a cure this problem I recently replaced the clutch ,friction plate,diaphram and release bearing I did not have the flywheel skimmed I put new engine & g/box mounts on.The judder is still there .I have TT drive shafts fitted and have spoken to Tony re this problem He did not think it was a drive shaft problem they are assembled correctly,I cannot move the diff. casing with a lever,the prop shaft has new universal joints fitted,all the rear bushes seem ok. The diff has a small ammount of back lash .Everything seems ok .With the car on jacks it does not happen.It is nearly undriveable in traffic. Any ideas? what have I missed?
Regards John S41969 DHC

["Bob Layman"]

--- In ***@***.***, "John Harrison" <johnharrison@d...>
wrote:

sweet.I can feel it through the clutch pedal but only at initial take
off
*************************************

John,

I would suggest two possibilities based on your info and inference
that all listed actions did not change the shudder.

Can you feel the shudder at very low speeds in the various gears or
only on takeoff (slipping the clutch)? If the latter, then I would
worry that the flywheel should have been trued/ground when you took
all the listed actions.

If the shudder is present under high torque at most speeds in 1/2/3
gears and noticeably less in 4th, then you might have a failing
gearbox input or output bearing (rare). However, this should show up
on quick getaways also so is unlikely to be the problem.

Bob Layman

[triumphelan]

Thanks for the reply Bob
I only feel the judder whilst slipping the clutch at take off,it will also judder in 2nd gear at take off .I do not get any judder at any other time in any higher speeds than say 2mph
Regards John S41969 DHC
----- Original Message -----
From: Bob Layman
To: ***@***.***
Sent: Monday, May 02, 2005 4:46 AM
Subject: [LotusElan.net] Re: Judder on take off


--- In ***@***.***, "John Harrison" <johnharrison@d...>
wrote:

sweet.I can feel it through the clutch pedal but only at initial take
off
*************************************

John,

I would suggest two possibilities based on your info and inference
that all listed actions did not change the shudder.

Can you feel the shudder at very low speeds in the various gears or
only on takeoff (slipping the clutch)? If the latter, then I would
worry that the flywheel should have been trued/ground when you took
all the listed actions.

If the shudder is present under high torque at most speeds in 1/2/3
gears and noticeably less in 4th, then you might have a failing
gearbox input or output bearing (rare). However, this should show up
on quick getaways also so is unlikely to be the problem.

Bob Layman
















------------------------------------------------------------------------------






***@***.***

[rgh0]

John

My brake and clutch guy ( who races a Lotus Cortina) will never
guarrantee a pressure plate and clutch plate rebuild or replacment
unless he gets to see and if necessary regrind the flywheel clutch face.

He says its based on long and bitter experience and is possibly your
problem. Given all the other things done / checked on the drive train
hard to see anything else except perhaps an internal gearbox problem.

I had a gear box problem with the layshaft becoming loose and affecting
the gear alignment in my race car which gave me some shudder on easy
take offs but this is unlikely in a road engine and it also gave gear
engagement problems that ultimately lead to syncro ring failure

Rohan

[saarhus]

John,

A couple of things to check, not necessarily in priority order. The clutch disk lining might be contaminated. Just a hint of brake/clutch fluid on the lining could cause judder. Attempts to burn it off with a torch are usually not successful. Of course this is only done with the disk removed. ;^) Replacing the lining AND cleaning up the flywheel face are the only cure in this case. This is the "traditional" method. I have not had occasion to try Bra-Kleen or other such, this may possibly help as well.

Second, look for worn out engine mounts or transmission mount, or both. A clue that all is not well in the engine mounts might be a groove worn in the top of the right-hand footwell by the airbox back plate. HTH

Cheers!

Stan


Thanks for the reply Bob
I only feel the judder whilst slipping the clutch at take off,it will also judder in 2nd gear at take off .I do not get any judder at any other time in any higher speeds than say 2mph
Regards John S41969 DHC
----- Original Message -----
From: Bob Layman
To: ***@***.***
Sent: Monday, May 02, 2005 4:46 AM
Subject: [LotusElan.net] Re: Judder on take off


--- In ***@***.***, "John Harrison" <johnharrison@d...>
wrote:

sweet.I can feel it through the clutch pedal but only at initial take
off
*************************************

John,

I would suggest two possibilities based on your info and inference
that all listed actions did not change the shudder.

Can you feel the shudder at very low speeds in the various gears or
only on takeoff (slipping the clutch)? If the latter, then I would
worry that the flywheel should have been trued/ground when you took
all the listed actions.

If the shudder is present under high torque at most speeds in 1/2/3
gears and noticeably less in 4th, then you might have a failing
gearbox input or output bearing (rare). However, this should show up
on quick getaways also so is unlikely to be the problem.

Bob Layman

[Elan45]

And then look at the diff torque rods. The rubber bushes that are on eitherside of the diff housing will get oiled over time and get spongy and soft.They can be replaced with shock rubbers. Then, you also need to take them loose from the frame at the front end and hope that the frame is still whole in this area. Since your car si an early S4, it might have the welded in bolts to secure the front end of the rods, but maybe not. This is a very delicate area of the Elan chassis and if it is cracked and broken, will causethe symptoms you describe. The frame can be repaired, but be very careful.

Roger



A couple of things to check, not necessarily in priority order. The clutchdisk lining might be contaminated. Just a hint of brake/clutch fluid on the lining could cause judder. Attempts to burn it off with a torch are usually not successful. Of course this is only done with the disk removed. ;^) Replacing the lining AND cleaning up the flywheel face are the only curein this case. This is the "traditional" method. I have not had occasion to try Bra-Kleen or other such, this may possibly help as well.

Second, look for worn out engine mounts or transmission mount, or both. A clue that all is not well in the engine mounts might be a groove worn in the top of the right-hand footwell by the airbox back plate. HTH

Cheers!

Stan


Thanks for the reply Bob
I only feel the judder whilst slipping the clutch at take off,it will also judder in 2nd gear at take off .I do not get any judder at any other timein any higher speeds than say 2mph
Regards John S41969 DHC
----- Original Message -----
From: Bob Layman
To: ***@***.***
Sent: Monday, May 02, 2005 4:46 AM
Subject: [LotusElan.net] Re: Judder on take off


--- In ***@***.***, "John Harrison" <johnharrison@d...> wrote:

sweet.I can feel it through the clutch pedal but only at initial take off
*************************************

John,

I would suggest two possibilities based on your info and inference
that all listed actions did not change the shudder.

Can you feel the shudder at very low speeds in the various gears or
only on takeoff (slipping the clutch)? If the latter, then I would
worry that the flywheel should have been trued/ground when you took
all the listed actions.

If the shudder is present under high torque at most speeds in 1/2/3
gears and noticeably less in 4th, then you might have a failing
gearbox input or output bearing (rare). However, this should show up
on quick getaways also so is unlikely to be the problem.

Bob Layman


























**********************************************************************
This email and any files transmitted with it are confidential and
intended solely for the use of the individual or entity to whom they
are addressed. If you have received this email in error please notify
the system manager.
This footnote also confirms that this email message has been swept by
MIMEsweeper for the presence of computer viruses.

**********************************************************************

[elansprint71]

John Harrison wrote:


Are the diff mounts OK and correctly adjusted ?
If so, I hate to take issue with Tony, as he has far more experience in
these things than me, but... given the stuff you have done to try to
sort out the judder, my bet is on a worn component in the TT shafts. Can
you borrow/fit some substitute shafts and try it out? Can you feel any
play at all in the TT shafts? On full lock, left/right does it feel any
different when you start off?
Cheers,
Pete.

[steveww]

Check the bushes on the diff torque rods and the diff mounts.

John Harrison wrote:

--

Regards,

Steve Waterworth
***@***.***

Einstein: "The faster you drive, the slower you age..."

[tdafforn]

Are you sure its judder, I had a sticking servo combined with a slight
out-of-true rear brake disk, which gave a similar sensation when I
pulled away.
Cheers
Tim

Steve Waterworth wrote:


--
Dr Tim Dafforn
MRC Fellow
Biosciences
University of Birmingham
Edgbaston
Birmingham
B15 2TT
(0121) 414 5881


--
Dr Tim Dafforn
MRC Fellow
Biosciences
University of Birmingham
Edgbaston
Birmingham
B15 2TT
(0121) 414 5881

[DGanzer]

John,
Another often overlooked cause of clutch judders is excessive end play of the
crankshaft caused by worn thrust bearings.
It's pretty easy to check, not so easy to fix......

Dave Ganzer

--- In ***@***.***, "Rohan Hodges" <rghodge@o...> wrote:

[lotuselan2]

Dave

Aren't oversize thrust bearings available? Dropping the pan and one bearing
cap is "all" that is required.

Ken



_____

From: ***@***.***lto:***@***.*** Behalf
Of dave_ganzer
Sent: Tuesday, May 03, 2005 10:56 AM
To: ***@***.***
Subject: [LotusElan.net] Re: Judder on take off



John,
Another often overlooked cause of clutch judders is excessive end play of
the
crankshaft caused by worn thrust bearings.
It's pretty easy to check, not so easy to fix......

Dave Ganzer

--- In ***@***.***, "Rohan Hodges" <rghodge@o...> wrote:











CopyrightC LotusElan.net and the author:





_____