Harsh vibration under heavy exceleration

[dangle172]

It seems to be coming from the engine and right through the exhaust system. Engine mounts? What damage is this doing under normal driving conditions?

 

[stan*]

Downpipe on the subframe, likely an engine mount is shagged.

 

[dangle172]

Cheers Stan. How much should i expect to pay? Would it be best to replace both of them?

 

[stan*]

its probably the dogbone, ckeck it for excessive play, not sure how much they are tbh from renault.

TMS will sort you one though.

 

[James.f]

its probably the dogbone, ckeck it for excessive play, not sure how much they are tbh from renault.

TMS will sort you one though.

JMS

If its the dogbone, just replace the bushes with powerflex bushes, they tend to last much longer,

 

[dangle172]

No the dog bone is new, only put it on a couple of month back. The vibration only started yesterday after i remover and replaced my lower inlet. I loosened the bolts on the top mount. Do you think this could be the problem?

 

[James.f]

Ahh, ye try and tighten that more, should be rock solid, or it could be that that mount is worn,

 

[W17GLE]

I'd try undoing all the bolts and resettling the engine then tighten everything up it may have just moved further back than it was before. If not then one of your mounts is on its way out.

 

[dangle172]

If i totally undo the bolts the engine will drop wont it. Never changed a mount before

 

[piggoy]

Loosen the bolts on the chassis side of the top engine mount and pull the engine towards the front of the car.

 

[dangle172]

ok thanks once again piggoy, big help. Well try tomorow

 

[Jonny1*2]

Remove the under tray, jack the engine on the sump (put a block of wood between the jack and sump though) to support the engine when you remove the top mount.

When tightening the bolts on the cam cover you ideally want no weight of the engine to make it harder work. So just support the engine at the height it is when mounted if that makes sense. ALL bolts on the mount and the cambelt top cover need to bt 65Nm

 

[dangle172]

Remove the under tray, jack the engine on the sump (put a block of wood between the jack and sump though) to support the engine when you remove the top mount.

When tightening the bolts on the cam cover you ideally want no weight of the engine to make it harder work. So just support the engine at the height it is when mounted if that makes sense. ALL bolts on the mount and the cambelt top cover need to bt 65Nm

Cheers for that jonny, wasn't too keen on the idea of putting a jack under my sump but i guess it'll be fine so long as i just take the weight of the engine.

 

[lazy_arse_pie]

ive got a prob near enough the same

does yours do it when pulling off a bit quick and also when giving it some past like 5K

 

[dangle172]

Yeah its the same but it starts about 3500k-4000k. And it sounds very wrong indeed

 

[lazy_arse_pie]

yeah same here , like vibrates right through the car ?

 

[andyclio172]

My car is doing exactly the same. Perfectly fine under normal driving conditions but as soon as you floor it and it goes over 4000 rpm the noise is aweful. I thought it was my exhaust but it obviouslt isnt.

 

[piggoy]

To do what Johnny1*2 says you will need to support the engine under the sump with the jack and a block of wood - but you will only need to do that if you feel you need to undo the top engine mount bolts on the engine side. The bolts on the engine side are torqued up to 65Nm and lock the mount in a stationary position.

However the engine mount on the chassis side is slotted and so the engine can be slided backwards and forwards by loosening them slightly. If you undo the chassis side bolts slightly you don't need to support the underneath cos the weight of the engine is supported on the chassis itself.

I'd try sliding the engine on the slots first before you decide to undo the engine side bolts. Sorry for the essay.

 

[dangle172]

To do what Johnny1*2 says you will need to support the engine under the sump with the jack and a block of wood - but you will only need to do that if you feel you need to undo the top engine mount bolts on the engine side. The bolts on the engine side are torqued up to 65Nm and lock the mount in a stationary position.

However the engine mount on the chassis side is slotted and so the engine can be slided backwards and forwards by loosening them slightly. If you undo the chassis side bolts slightly you don't need to support the underneath cos the weight of the engine is supported on the chassis itself.

I'd try sliding the engine on the slots first before you decide to undo the engine side bolts. Sorry for the essay.

So i only need to loosen the ONE bolt on the chassis side of the top mount and pull the engine forward and tighten it back up? Is this also tightened to 65Nm? I'm doing the job first thing in the morning so if anyone can advise i would be grateful.

 

[shevo182]

Ive got the same problem with mine. its only started doing it in the last week or so. my vibration happens in 2nd and 3rd when it gets to 5k.

Thought at first it could be a drive shaft or a misfire under load, but ive ruled them out and now im starting to think its excessive engine movement caused by worn bushes.

 

[piggoy]

So i only need to loosen the ONE bolt on the chassis side of the top mount and pull the engine forward and tighten it back up? Is this also tightened to 65Nm? I'm doing the job first thing in the morning so if anyone can advise i would be grateful.

I'm not saying that this will definitely fix your problem but it is definitely worth trying before you look elsewhere.

View attachment 38681

Loosen the FOUR bolts circled and pull the engine in the direction of the arrow. I tighten them up to about 30Nm cos the threads in the chassis don't seem as substantial as the ones on the engine side of the mount. The Renault documents I gave you don't quote the torque of those bolts. I think they prefer you undo just the one bolt on the chassis side and leave the four untouched.

If this doesn't fix your problem I'd then get the jack under the engine and check the tightness of the bolts on the engine side. Remember you must support the engine if you undo these bolts. If you didn't support the engine when you previously undid them to play with your manifold that may very well be the source of your problem - so i'd suggest supporting the engine, undoing them, and then torquing them up properly with the engine supported.

If still no success then your mounts are fooked!

 

[dangle172]

Ok cheers again piggoy.Will try this and see what happens

 

[jaysjetski]

My car is doing exactly the same. Perfectly fine under normal driving conditions but as soon as you floor it and it goes over 4000 rpm the noise is aweful. I thought it was my exhaust but it obviouslt isnt.

have you checkec the driveshafts? driveside is a common fail.

a few ways to check. jack up drivers side put the car in gear and turn the drivers wheel by hand, if it moves then the driveshaft has had it.

another way is to raise the car, put in gear again and try and turn(wobble) the driveshaft.

another is to get a mate to stand outside, put car in gear and drive foward slowly, then go backwards then fowards etc. if it clucks each time, again drive shaft.

 

[dangle172]

Right iv done whats been said with the top engine mount and the vibration is still there. So i checked the drive shaft's and there OK too. I jacked the car up, put it in 1'st and there is a little bit of play on the wheels but only until the slack has been taken up if that makes any sense. Does that sound right??
Has anybody else got any ideas before i pull what little hair i have out!!

 

[stan*]

JMS

If its the dogbone, just replace the bushes with powerflex bushes, they tend to last much longer,

No mate, I meant TMS....

its a motor factors in Carlisle

 

[stan*]

What exhaust is on it? Try adjusting it so as to move the d/p away from the subframe.

Also, did you try shifting the engine BACKWARDS, i.e opposite to whats in that pic above?

 

[dangle172]

What exhaust is on it? Try adjusting it so as to move the d/p away from the subframe.

Also, did you try shifting the engine BACKWARDS, i.e opposite to whats in that pic above?

Thanks Stan

I'll try to get under it tomorrow so i can see whats going on. I never tried moving the engine back. I looked at the mount and it seems live its as far forward as it can go. But iv never touched it before so didn't think that was the problem.

If your feeling helpful I'll gladly let you have a wee look at at

 

[dangle172]

Still no idea what this noise is. Can anyone help!!

 

[AlexG]

Mine does the same and ive yet to cure it.

Ive changed the upper engine mount, dogbone mount and upper gearbox mount below the battery. Tried pulling the engine forward to put it still does it.:dapprove:

 

[dangle172]

well it sounds like you have tried everything i would have ended up doing so I'm now thinking its either something involving transmission of something stupidly simple. I'm hoping its the latter!

 

[bigup7]

Did you find what was causing the vibration mate?

 

[dr16]

bump did you ever cure it? I have replaced dogbone and upper drivers side engine mount which has seriously reduced my knocking/vibrations but theyr slowly creeping back. Seems to be worse in the cold/first thing in the morning? Upper gearbox mount is next.