Author Topic: Symptoms of dog bone or engine mount problems?  (Read 18394 times)

Offline The Dave

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Symptoms of dog bone or engine mount problems?
« on: 12 March 2010, 00:35 »
Had this in my clutch thread but don't think many people read the last bit.

Long story short, my car has had new engine mounts in the last couple of years and a polybushed powerflex set fitted to the dog bone mount. Car is a 1999 AGU GTI, engine standard really bar a remap.

This monday gone, I had a new clutch fitted (single mass conversion was carried out - a Valeo kit). Since this though the gearchanges do feel a little bit notchy/harder and the main thing which concerns me now is if I let of the throttle even when it's low throttle, there is a sort of obvious snatch/jerk and a feel of say worn mounts? No smoothness. As if the car is moving backwards/forwards once, quickly, then settling. No knocking though. It's as if since it has been taken to bits, there's "looseness" introduced into how the car drives. As if mounts aren't as tight.

If this is related to mounts or the fact the DMF has now been removed, I'm unsure. Obviously I can compensate a little if I'm smoother on the throttle but it's as if the box isn't attached as "tight" as before. I'm no mechanic so it's all over my head really.

I guess the gearchanges themselves aint so bad, it's as if the gearbox feels a bit more "loose" though? It's hard to put into words really. It's as if there is "movement" on the box if I'm not dead smooth? The changes are a little bit notchy but not "bad" if you get me, but it's cold out, and it's felt the same for a bit since winter came and low low temps all the time anyway. I intend to get the box oil changed soon as no idea when it was last done.

I am thinking more to do with the dog bone mount as something else I've noticed since the clutch was changed:

It's polybushed... now previously I had no jerk coming on or off the throttle, not snappy/snatchy/jerky at all really, BUT! I did have vibration in the cabin at up to 2k rpm when the car was under load.

Now, I've clicked today, said vibration has gone. Everything is very smooth under 2k, but as I say I get the jerk as if somethings moving forward and backward, just once, very quickly then settling. No noises though.

Just points me to assuming the dog bone mount isn't as tight??? Make sense?

Any comments would be great :)

Offline Purely VAG

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Re: Symptoms of dog bone or engine mount problems?
« Reply #1 on: 12 March 2010, 11:46 »
Sounds like it could be mate, only way to know for sure is put it up on a ramp and just use a pry bar to check.

Just go to like kwik fit or somewhere and ask them to check where your knockings from. Then go on your merry way :)

Unless you fancy getting under it?

✉ Jrd@PurelyVAG.co.uk // www.PurelyVAG.co.uk

Offline The Dave

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Re: Symptoms of dog bone or engine mount problems?
« Reply #2 on: 13 March 2010, 17:38 »
Was hoping get my mechanic look today, but he was snowed under, so I've booked it in for thurs morning for a check over.

I don't get any knocking which is the weird thing lol. Will see if we find anything on thurs :)

Offline pitchy

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Re: Symptoms of dog bone or engine mount problems?
« Reply #3 on: 13 March 2010, 19:58 »
ive got this with mine too mate , as i engage and dissengage through gears i feel the "slack" , i did have the same thing with my old nissan primera gt though , i thought it was a cv , as i went to strip down the hub i found that the main hub bolt was slightly loose! this is the first thing im gona check on mine when i get the wheels off at the end of the month
2002 gti aum mods-cai / n75j / 007p / stg1 remap / rs4 reps .
things done in the last few months - new temp sensor / new gearbox oil / anni matts / painted interior trim / debadged /
things to do - refurb wheels-satin black / coilovers / paint headlights internals black / fit fmic / 3" turbo back / stg2 remap

Offline The Dave

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Re: Symptoms of dog bone or engine mount problems?
« Reply #4 on: 13 March 2010, 20:00 »
Yeah I guess slack is a good word for it :) It aint too bad but I'm very picky! Haha.

Hopefully it aint something like that, just putting it down to whatever was removed and refitted... but looking at the state of my engine cover after I popped the bonnet today (smashed to bits and bodged together with fibreglass underneath!!) and a strewn of loose nuts and washers.. god knows how well the clutch was fitted :(

So having the car inspected on thurs.

Offline gus_79

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Re: Symptoms of dog bone or engine mount problems?
« Reply #5 on: 15 March 2010, 09:20 »
Had this in my clutch thread but don't think many people read the last bit.

Long story short, my car has had new engine mounts in the last couple of years and a polybushed powerflex set fitted to the dog bone mount. Car is a 1999 AGU GTI, engine standard really bar a remap.

This monday gone, I had a new clutch fitted (single mass conversion was carried out - a Valeo kit). Since this though the gearchanges do feel a little bit notchy/harder and the main thing which concerns me now is if I let of the throttle even when it's low throttle, there is a sort of obvious snatch/jerk and a feel of say worn mounts? No smoothness. As if the car is moving backwards/forwards once, quickly, then settling. No knocking though. It's as if since it has been taken to bits, there's "looseness" introduced into how the car drives. As if mounts aren't as tight.

If this is related to mounts or the fact the DMF has now been removed, I'm unsure. Obviously I can compensate a little if I'm smoother on the throttle but it's as if the box isn't attached as "tight" as before. I'm no mechanic so it's all over my head really.

I guess the gearchanges themselves aint so bad, it's as if the gearbox feels a bit more "loose" though? It's hard to put into words really. It's as if there is "movement" on the box if I'm not dead smooth? The changes are a little bit notchy but not "bad" if you get me, but it's cold out, and it's felt the same for a bit since winter came and low low temps all the time anyway. I intend to get the box oil changed soon as no idea when it was last done.

I am thinking more to do with the dog bone mount as something else I've noticed since the clutch was changed:

It's polybushed... now previously I had no jerk coming on or off the throttle, not snappy/snatchy/jerky at all really, BUT! I did have vibration in the cabin at up to 2k rpm when the car was under load.

Now, I've clicked today, said vibration has gone. Everything is very smooth under 2k, but as I say I get the jerk as if somethings moving forward and backward, just once, very quickly then settling. No noises though.

Just points me to assuming the dog bone mount isn't as tight??? Make sense?

Any comments would be great :)

I have the same issues with my car, i bought it with a knackered clutch so dont know what it drove like in the first place! When i replaced my clutch i changed the flywheel for a single mass and put in a performance sachs clutch, I too have trouble engaging gears, i think i have an issue with my 1st/2nd gear synchro as well which doesn't help matters but the other gears can feel notchy at times.
The "slack" which you mention is also present on my car so i know exactly wht your trying to describe, I have a full polly bush kit fitted but at present haven't had time to do the dog bone bushes on the gearbox. I'm in the trade myself and have checked and re-checked all mounts for engine and transmission and all other possible factors for this and found nothing so i have assumed it was because of the single mass flywheel? But im open for anyone to correct me on this.

Hope its of some comfort that your not the only one suffering from this?

Offline The Dave

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Re: Symptoms of dog bone or engine mount problems?
« Reply #6 on: 15 March 2010, 10:18 »
it is lol, after all the raving about how good the SMF setup feels... if everythings on as it should be, then it doesn't feel more positive at all.

Will post back on thurs any findings by my mechanic :)

Offline Muzza_GTI-1.8T

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Re: Symptoms of dog bone or engine mount problems?
« Reply #7 on: 16 March 2010, 15:59 »
Do let us know please mate coz iv got the smf setup with valeo too n have the exact same problem but mine has got to the point of erratic knocking and juddering when comming off the clutch when pulling away it sounds like an engine mount but its not just checked this weekend.hopefully was going to put a new clutch in this saturday to see if it resolves the problem.

Offline haf1zur

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Re: Symptoms of dog bone or engine mount problems?
« Reply #8 on: 16 March 2010, 16:10 »
with the bonnet up, press on the gas while someone watches or get someone to press the gas, in neutral obviously and see how much the engine moves and which direction. Make sure the person doing the watching is on the side rather than the front for safety.

if it moves front to back a lot then its the dogbone mount on its way out


Offline PishY

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Re: Symptoms of dog bone or engine mount problems?
« Reply #9 on: 16 March 2010, 17:16 »
ive just replaced myne, with a standard item, and the difference between the 2 was immense, the flex of the old one was to easy to move, and the engine did bounce around back and forth a little, and a plus was the easy installation, it took 5mins

changed this and it still shook about, and found it was an air leak on the lower pcv breather pipe under the inlet manifold, made up a quick fix with some copper and rubber and my engine moving had stopped all together! and the car feels so much better now.