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MG MGF Technical - MGF VVC 1.8 Blown motor (stripped timing belt)

This is a really strange problem that I need some help understanding. I have a 1998 MGF that has had nearly every update/fix that is availible for this car. The headgasket has been changed... more or less... everything is up to date... and now it's dead.

The timing belt was changed at 90k KM and just a couple of days ago while calmly driving home, I shifted into 3rd gear and heard a grinding. I thought I had missed a gear, but the engine had shut off.

So now after towing it to the local tech here in town, he says the following chain of events happend.

He says that one of the cam cap seal behind the cam gear failed and leaked oil onto the timing belt, causing it to become soft and loose all of it's teath... and now it has dropped valves and it's dead.

Something doesn't sound right about that situation to me. Is it normal for a seal like that to go at 100k KM? If so... I still don't see how the teath stripped. Sounds to me like whoever tightened the TB tightened it to much... or maybe the tensioner was overtightened.

Any ideas or insight are greatly appreciated!
SBJ Jamison

Hi,

please can you add whether a VVC or a 120PS standard ?

The cars VIN would be of interest also (secret under our both eyes only if you put it there >> http://www.mgfcar.de/vin <<)

Have you already complained about lack of sensitive works at the Garage where the belt change works got done?

I think a overtightened belt could be a reason, but you would have heard this earlier with a strange noise from the engine.

Regards
Dieter
Dieter

This is a 145ps VVC motor. I was thinking that it could be an overtightened belt as well... so did the guy at the ATU I spoke to before we towed it to the MG guy.

The question is still how it is leaking out of that cam cap seal... would a dead motor caused by dropping a valve cause enough pressure to blow it out?
SBJ Jamison

Wow - now that is a pretty serious consequence of a leaking cam seal SBJ! :o(

Engine oil can be pretty bad news for rubber components, so 'rot' of the cam belt would not be that far fetched as a possible explanation of what happened.

Once a tooth from the belt has been stripped off, the valve timing will go, and valves will impact upon pistons = dead engine.

Bad news. :o(

IMO Cam seals don't simply suddenly fail - they are likely to start leaking very slowly, and over a period of time get progressively worse.

I have no idea when your head gasket was replaced, but I would expect that a leaking cam seal would have been obvious at that time - assuming that it was leaking then: the tell-tail signs would be easy to spot.
Rob Bell

Sorry to hear about the total failure of the engine,BUT there is obviously something more to the story than just an oil leak to give this....
1.If the cambelt was "overtight" you would have heard that immediatly after the belt-change. A high-pitched sound comes from the belt,it is easily heard even with a sports-system;O)
2.The force applied on a overtight belt is not that much more than on a correct tensioned one due to the mechanism of the manual tensioner. So IMO the only drawback of an overtight belt is more stresses to the involved parts,waterpump,tensioner etc. And in due time the belt will settle with the tension and bedd in.
3. Oil on the belt is bad as some types of rubber gets soft and swell in short time after contact with oil. The toughest forces on the cambelt is at low revs,usually failure happends at idle or start-up !
Any oilleak in this area would be spread around by the fast moving parts.Any sign of oil where you normally park the car?

It is worth checking that no other failure took the teeth off the cambelt. Seized waterpump? The usual broken cambolt? Crankshaft pulley re-fitted with correct torque AND some kind of LockTite fluid on the threads? Possible VVC-mechanism failure ?
A good mechanic can probably give you the full story after having a closer look.
BR, Carl.
Carl

Looks like the to tight TB is not it then... no sound.

The head gasket was changed by the same guy who is looking at it... so I'll see if he had noticed it then (if he would tell me in the first place).

He said the waterpump was bad... didn't say seized, but I'll definitely ask!

Thanks for all of the help?

Anyone want a 1998 MGF Dark Green w/ black interior? The car is in great shape... minus the motor. I just replaced the tierod ends last month, and a lot of updates have been done. Great body for someone who needs one.
SBJ Jamison

Don�t throw in the towel yet !
Surely there are a lot of second hand engines available in Germany? Probably the fastest and cheapest way to get the car rolling again. Anyway if the valves ,pistons etc. are damaged the repair cost can be well over the cost of a documented good VVC engine from the scrap-yard.
BR, Carl.
Carl

... and a Honda V-Tec can be made to fit! ;o)
Rob Bell

The towel is unfortunately thrown... I'm currently looking for a 2nd hand motor to put in, but they are far from easy to find so far. I will be moving back to the states soon, so I was going to have to sell it anyway. How much should a second hand motor run? The guy at the shop quoted �5000 for a new motor and to install it... however that's a few thousand less than what the car is worth. I know the fab required to put in a motor from another car (I have a car in the states like this)... otherwise I would do it.

If I can get my hands on a used motor at a good price I will rent a garage unit and put it in myself... I think this guy is ripping me off.

SBJ Jamison

5000 euro? Good grief - you should be able to buy at least 2 or 3 VVC engines for that money!!!

VVCs are currently in very high demand - due in no small part because the engine has such an excellent cylinder head for high performance tuning.

No idea about shipping costs, but it may be worth contacting MGF Centre, Midland MGF and various Rover breakers in the UK if no suitable power plant can be identified locally.
Rob Bell

>>... and a Honda V-Tec can be made to fit! ;o)

Honda engine is OK (I have one in my TypeR); but not so good on torque, and very heavy.

I like the K so much, I put an MGF engine into my midget (BTW: �650 for a complete 1.8i with 4K miles/4 months old). Take a look at this link and gain new respect for the engine in your F/TF:


http://www.sandsmuseum.com/cars/elise/thecar/engine/kingk.html

Anthony
Anthony

Sorry to hear about your problems. I've been there, done that, got the T-shirt...

In my case the timing belt tensioner failed at just over 150k miles. I was quoted around �3k plus fitting for a new engine (non-VVC), or a minimum of �1500 to fix the existing engine! I decided to p/x the remains of the F for a pre-registered ZS180.


Ralph
Ralph

> ATU
by godness, I hope you didn't let them do anythng at the MGF.

Anyway, where are you and more important, where is the car ???
What Gargage is the _MG guy_ ?

Good options to get a repair or selling of the engineless body are usually in the north-rhine area and Lotus Elise Tuners.

I'll be off for hols tomorrow night.
Send an Email or use the above webform link if I should forward you to some contacts in DE.

RED Motorsport in Wuppertal. In Remscheid is Heyer, another Elise Tuner is Korff.
Krefeld a good friend with a small workshop.

Eifel Area is Como-Tec. Hannover is Rotec.
Wiesbaden is Moto-Concept.

We have advert boards and Forums in German language.
So hurry up, if you really need help.

Email > mgf at mgcc dot de

Regards
Dieter
Dieter

This thread was discussed between 30/05/2005 and 31/05/2005

MG MGF Technical index

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