Sparking/grinding Under Load In Reverse?

[Sinbad 16]

When my car was being tested the tester told me one of the lads spotted there was a few sparks coming from underneath the car as he reversed off the mot brake testing rollers.He showed me when i got there and in reverse under load with the handbrake on, there was indeed sparks coming from the car and it sounded like something was grinding ever so slightly.When the engine moved under load it was happening and when idling or even driving normal it was fine.....

Any ideas what it could be?????

[Anthony 1,003]

Obvious question is where were the sparks coming from?

[Sinbad 16]

The front of the block sort of at the bottom flywheel side,i have taken the shield off at the bottom and that little one at the top of the flywheel and no clean metal grind marks at all

[Tom Fenton 1,547]

My first check would be all the engine to gearbox bolts are in and tight.

[Sinbad 16]

They seem to be.

On the starter side of the teeth on the fly there is clean metal about 1mm into the tooth.Starter catching maybe??

[Anthony 1,003]

Including the rear cap head bolt that goes in from the engine side? That's usually the first one to come loose, especially if the gearbox as been off at some point and either the wrong bolt fitted and/or the dowels missed when refitting.

[Sinbad 16]

Is that located at the back of the engine?

[allye 530 3 Cars]

yep, right down the back near the speedo drive sort of area. As Anthony says, goes in the opposite way round to the rest.

[Sinbad 16]

Right,there is one missing there then,could the engine be twisting and the box catching the flywheel perhaps??

The box is on the dowels fine though...

[Tom Fenton 1,547]

If there is one missing then it needs replacement then see if your problem has gone. I expect it will be. The bolt needs to be the right length as otherwise I think it will bottom out in the tapped hole in the gearbox side.

[Sinbad 16]

Could that really be the cause?? 1 missing bolt??

Anyone have a part number for it??

[Anthony 1,003]

I can't say whether it'll fix this particular issue, but certainly that bolt being missing tends to play merry hell with the operation of the clutch - basically, when you depress the clutch pedal, it tends to force the bottom of the gearbox away from the engine block so the engine and gearbox aren't square to each other. Usually you notice it first as the clutch dragging slightly, and as it gets worse, the gearbox starts to work itself loose and it comes away from the engine and gear selection becomes nigh on impossible and the starter won't engage properly.

 

It's a bit of a flawed design relying on that one bolt and it was rectified on the late XU engines (eg GTi-6) which have two bolts at the back and a further one low down at the front, to stop exactly that issue from occurring. Missing one or both of the dowels from the gearbox tends to significantly exacerbate the problem.

[Sinbad 16]

What you have just said there makes perfect sense to me,i can see how it would do that,then somepart of the bell housing is obviously catching clutch or flywheel.

I'll ring pug and order one then.

[cheesegrater 43 1 Cars]

IIRC its just an M10 bolt. Cant remember how long mind, wont be too difficult to measure.

[chipstick 382 1 Cars]

I'ts a cap head bolt isn't it?

[welshpug 1,666]

yup, 8mm allen headed, around 65mm long from memory, with a serrated washer as well.

 

 

 

 

6913 J4, superseeded by) 6913 N0, M10x1.5 - 70mm, £1.30

 

plus 2221 26, stop plate 70p.

Edited June 26, 2012 by welshpug

[Sinbad 16]

Welshpug your a hero.My local branch farted out of their mouth when i rang earlier

edit-and again just now-only available in packs of 5

Edited June 26, 2012 by Sinbad

[Tom Fenton 1,547]

I would just find a decent fastener store and buy an M10 cap head bolt 70mm long. 10.9 or 12.9 grade will be more than sufficient. The stop plate is a square washer to fit in the casting of the block, no doubt Peugeot will want to sell you a bag of 956, you can fashion something perfectly acceptable in 10 min from a standard M10 washer using a file.

 

These engine to gearbox bolts can be prone to working loose, so I now always threadlock them in. You will need to degrease the thread in the gearbox and the bolt with some spray solvent, then once that has evaporated use some threadlock of your choice to make sure they stay put. Also go round all the rest and double check they are tight.

[Sinbad 16]

Thanks mate,il sort one tomorrow i think.

I even said to partsman-"er i only want 1,the rest are just scrap arent they?!"

"thats what they are to us"

Er ok then,whatever!

Edited June 26, 2012 by Sinbad

[cheesegrater 43 1 Cars]

I'm pretty sure you can get away with using a standard m10 plain washer for the bolt can you not? Ive put a plain and spring on mine.

Edited June 29, 2012 by cheesegrater