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MG MGF Technical - VVC Engine Disaster - Help!

Hello all techno-buffs out there.
I urgently need some advice before my local MG service centre starts emptying my bank account.
My 7 year, 43,000 mile old MGF VVC failed me a couple of weeks ago. On my usual drive home from work, doing about 45-50 mph (2500-3000 rpm) a nasty zinging (??)noise started in the engine compartment and my first thoughts were of a bearing breaking up. Unable to stop safely immediately I drove on for another mile only for the engine to completely shut-down and I coasted to a halt.
The good old AA got me home and I concluded the cam belt must have snapped. On investigation the cam belt proved to be in good order with no teeth missing or damaged, the tension correct and all the pulley wheels etc. turning normally. A compression test though confirmed my worst fears with two cylinders down and I expect to find a nasty case of bent valve disease.
My theory is that the super-dooper VVC cam operating gear has failed in a big way and caused the cam timing to go anywhere it chooses.
Please tell me I'm wrong and all I need to do is clean the spark plugs.
Has anyone knowledge of this? I would like to write to MG-Rover with some background before I claim compensation. I work for Perkins Diesels (tractor engines) in the design dept. so I understand engineering issues.
Thanks in anticipation.
A Rawlinson

Hi,

Which two cylinders?

Regards, Kes.
Kes

Hi Kes.

Cylinders 1 and 2 (at the crankshaft/alternator pulley end).

Regards,

Tony
A Rawlinson

Hi Tony,

I asked because the VVC splits the camshaft operation on the inlet side into two, with the drive for cyls 1 and 2 being from the cam wheel/cam belt, and cyls 3 and 4 being through the exhaust camshaft and then by a short belt at the rear of the engine back to the inlet side. (The exhaust canshaft does not join in the benefits of VVC.)

After saying all that I have no answers. Maybe the lack of compression on 1 and 2 indicates that there is some problem with the VVC at that end, maybe it's coincidence. You need some pro advice.

Is the car at your home? Who can you trust within towing distance? Techspeed, MGF Centre?

Good luck, Kes.
Kes

Hi Kes

Thanks for your note.
After posting my original message I searched the 2003 bulletin board and found a note from J. Connell-Smith of London who describes similar breakdown symptoms to mine. Mike (no surname) replied with a plausible cause, specifically, the cam pulley bolt for the inlet cam coming loose and the pulley coming adrift causing the cam timing to go out and subsequent valve damage.
My 'F' is at home in my garage and my next step will be to take the cam cover off and turn the motor over gently by jacking up a rear wheel, selecting a high gear and rotating the wheel. If Mikes theory is right I may see one half of the inlet cam turning and the other half not and the root cause will be established.
The real bad news is the potential costs. Mike indicated a bill of between £500 to £900. A car mechanic relative of mine thought £1500 more likely.
The following link provided by Dieter K. (thanks D) included an invoice for a whopping £2610.59 . Gulp!!
http://www.mgfcar.de/hgf/cam_bolt.htm

What I need to know now is how many MGF 1.8VVC owners have experienced this failure. On a purely selfish note I would to have some ammunition to fire at the guys at MG/Rover for their poor design and validation process for the valve train components. If it is a frequent failure then the manufacturers have some moral obligation to stand some of the resultant costs.
Has anyone out there had any success trying to pursue this with MG/Rover?

Thanks again all.
Tony.

Thanks
Tony Rawlinson

Tony,

I suspect the Mike that you refer to might be none other than Mr Satur himself.
David Clelland

Can I suggest a call to Techspeed..

They are reasonably close to you...

Stu
Stu Dickens

I would suggest a call to Mike Satur - he is the Mike referred to in the post and has seen Cam Bolt failure on more than one occasion.

Paul
P9 VLS
Paul

Was there not a recall for these 'f's to have the tension on the cam bolt checked? If so, might be worth trying to find out if this was done (service history)?
Leigh

More on the cam bolt problem here too Tony: http://www.mgf.ultimatemg.com/MGF_recalls.htm#r2

As Leigh says, check to see if the necessary rectification work had been carried out - as there was a batch of VVCs in late 1998 that do suffer more than their fair share of problems :o

Numbers? There's been a few celebrated cases on this BBS, but it is not an especially common problem.
Rob Bell

Thanks everyone for all your comments.
I have owned my F from new and do not remember any recall for the cam bolt torque. I'll check with my dealer - Trinity Motors of Hinckley.
I would like to know the reasons why only late '98 cars were recalled. How did this show up on the production process records? It would have been nice of MGR to ask dealers to adjust the torque on the bolt when all pre '99 vehicles have their next major service. Maybe this happened. I'll find out.
As a point of interest, my car is still on its' original cam belts and they look in excellent order. The car has 43,000 miles on the clock and they have all been relatively gentle miles. I like to push the handling more than the engine.
In my last note I said I would turn the motor over and check to see if all the cams were turning. I did and, no suprises, front end cam pulley turns but cam does not. Bugger!!! A set of four nicely bent valves are evident as well.
I have a theory.
My problem has been caused by the break-up of the VVC sleeves, pins and especially the needle roller bearings and this has resulted in a siezure of the components. The cam belt has continued belting around and at the point of siezure has 'pulled' the cam pulley free from the (too loose) holding torque of the cam pulley bolt. I'll know this for sure when the nominated repair shop starts its' autopsy.

I'll keep you posted on this and all the costs that are accrued.

Thanks again,
Tony

Tony Rawlinson

Tony, I think we will all be interested to hear how you get on. However, in view of your own statement that you have not had the car serviced to manufacturers specification (my car is still on its' original cam belts) I suspect you may get short shrift.

The service schedule calls for cambelts to be changed at 60 months or 60,000 miles WHICHEVER IS FIRST.
JohnP

> The service schedule calls for cambelts to be changed at 60 months or 60,000 miles WHICHEVER IS FIRST.

It was brought forward on the Elise service schedule. 54,000 miles IIRC but not sure of timescale.
Bob Millar

Interesting Bob.

Certainly we all agree they should be changed before 7 years.
JohnP

And brought forward on the F from 96k to 60k
Will Munns

Tony

Just to add to what others have said, if you have a cambolt failure, Mike Satur probably has more experience of this problem and haggling directly with MG-Rover(??) than anyone else although he might not wish to be reminded of the grief the company caused him.

From memory, the cam-bolt "recall" for VVCs coincided with a recall of all Fs for a re-designed seatbelt escutchion. The cambolts on VVCs were supposed to be tightened at the same time, so you may well find a single stamp in your log book referring only to the seatbelt.

To be fair to MGR, the cambolt incident is usually referred to in public as a "check" rather than a formal "recall", but the fact remains that a separate notice was issued and numbered either 056 or 058, (sorry I can't remember which).

Chris
Christopher Marshall

A056 was the seat belt escutchion - so was the cam bolt A058?
Rob Bell

The front inlet cam bolt was checked for the correct torque setting, if found to be incorrect it was not just tightened but refered back to Rover for action.This may have involved replacing the inlet cam assembly.HTH
Mike.
mike

This thread was discussed between 10/04/2004 and 16/04/2004

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