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3.4 engine seized a few questions / put me out my misery :-(

996lee

Well-known member
Joined
26 Aug 2014
Messages
748
Hi all

had a nightmare of a weekend :nooo:

my car was booked in for a full service and to have a coolant leak sorted and once again having another split on a dansk flexi joint sorted last friday

i was already expecting it to be an expensive weekend however....

the day prior i did about 400 miles in it but as i went to start it that morning there was a screeching sort of sound after it fired up!
which in my mind was possibly the starter motor giving up the ghost (has had a few slow cranks when hot over the last couple of weeks)
anyway on the return leg of my jouney after fueling up i went to start it and it went to turn over but felt like the whole engine was going to turn over with it
second attempt it fired but same again it felt a really heavy turn over which worried me
i got out listened to it and it was ticking over just fine and got me home with no fault at all

the following morning i go to start it and all i got was a single click
quickly got my jump leads out and still just a single click
not wanting to miss my slot at the garage i then tried to bump start it
on attempting this on letting out the clutch it locked its wheels

so thinking it was just me not building up enough speed i got my dad round and we used his car to tow it
and the same happend
i tried rocking it backwards and forwards in gear and the engine is seized solid
i did try hitting the starter motor a few times
and after that the click did sound more convincing that it was going to turn

i then got it towed to Zentrum in Nottingham obviously expected the diagnosis to be the worst

i was late for my slot so they are stripping bits off it today/tuesday to see what is wrong

but they have already told me they they removed the sump and thats clean with no trace of metal but they can see the flywheel is trashed (this is only a couple of years old lightweight flywheel)

so my question is could a stuck starter motor do that damage?
i'm aware i've not helped matters trying to bump start it if so

and secondly if this is likely what has seized the engine
what are the chances that 2 attempts to bump start it and it locking the wheels has trashed the crankshaft/ anything else whilst doing so?

sorry for the long post i'm obviously pretty gutted that a rebuild may be needed :sad:
 
I'm sure that Mike will be able to tell you pretty quickly. Best hope is that something on the flywheel failed which has locked it up from there, no engine damage. Could be snapped crankshaft which might 'just' mean a new crankshaft and no other engine damage.

Fingers crossed for you, somewhere between a new crank and a new engine is my guess. Good used 3.4l cranks are unfortunately like rocking horse sh!t.

MC
 
My guess is this is all flywheel related and your engine is fine.
 
Yeah as MC and Alex says sounds to me like the flywheel teeth are maybe damaged and holding onto the starter cog. Maybe the starter got lazy at retracting (that would be the screeching sound you heard).

Was it an alloy flywheel?

If thats the case just chuck an OE dual mass on. Hopefully no damage to the crank or main bearing from the bump start attempt.
 
Can't see any damage occuring bumping it as the only thing in motion is the gearbox and the locked flywheel has taken the brunt of that. No load would've been put on the engine. If amything, the gearbox/diff/driveshafts may be damaged but I doubt it.
 
Nightmare Lee.

Hopefully it's whats mentioned above and the engine has in fact survived.

Fingers crossed for you.
 
I'm keeping my fingers crossed and waiting for the phone call

@wasz It is a alloy flywheel I believe (from rpm technic that they use on their csr's)
 
996lee said:
I'm keeping my fingers crossed and waiting for the phone call

@wasz It is a alloy flywheel I believe (from rpm technic that they use on their csr's)

So alloy being softer than steel the teeth on the flywheel could have been damaged by the teeth of the starter which failed to retract properly, and then the next time you start the damaged teeth hold onto the starter even more and then the starter gets bent / stuck / whatever seizing the transmission.

Thats my internet diagnosis :D

Either that or its the other internet diagnosis of AARAGH IMS BEARING FAILURE and OMG BORE SCORE but I doubt it.
 
I second my learned friend with that diagnosis.
 
right had a call off mike at zentrum
it was indeed the started motor seized solid that had mangled the teeth of the flywheel
and there is no damage to the crank or anything else
and also good news was my coolant leak just needed a new jubilee clip to sort :thumb:

now i have absolutely loved my lightweight flywheel and the prices are around the the same as a dual mass so do i go for another :?:
 
Only if you sort your sticky starter motor out 1st.
 
alex yates said:
Only if you sort your sticky starter motor out 1st.

yep they are fitting me a new one :thumb:
 
Not sure I fully agree with Wasz, I would expect that the ring gear on the flywheel is steel and shrunk onto the alloy flywheel, cast iron flywheels are usually like this.

If the flywheel is undamaged, it may be possible to just have a new ring gear fitted and saving quite a lot - try asking the manufacturer.
 
maldren said:
Not sure I fully agree with Wasz, I would expect that the ring gear on the flywheel is steel and shrunk onto the alloy flywheel, cast iron flywheels are usually like this.

If the flywheel is undamaged, it may be possible to just have a new ring gear fitted and saving quite a lot - try asking the manufacturer.

i'll dig out the pic i took of it when it arrived (if photobucket still exists now)but if i remember correctly it was a one piece flywheel
i may be mistaken though
 

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