Rear Hex Gearbox Bolt

[steve@cornwall 100]

I've just lost the fourth hex bolt in a year I've got used to checking regularly and last weekend when replacing a driveshaft, it was tight as f@@k.Other bellhousing bolts are fine. Any ideas why it does this? It's getting rather tedious and I don't really want to use copious quantities of threadlock as the last thing I want is to round out the hex slot next time it's got to come out.

[SamGTi 0]

I too would be interested in a reply to this as mine did exactly the same last night, could only get it in so far before it started to fall out again...

[welshpug 1,627]

all I can suggest is to clean the threads, oil the bolt thread and head, and torque up with a torque wrench.

 

is it the bottom rear bolt? IIRC on a 205 there arent any brackets there so a normal bolt would suffice.

Edited October 13, 2007 by welshpug

[SamGTi 0]

Easier said then done IMO! Mine torques up to a set force and then won't go any more! It's just the bolt that goes through the block and into the bellhousing (I presume Steve's is the same?)

[welshpug 1,627]

sounds like the bolt is too long, is the washer still on it? there are 2 or 3 different lengths of bolts used here.

[steve@cornwall 100]

sounds like the bolt is too long, is the washer still on it? there are 2 or 3 different lengths of bolts used here.

 

Same bolt, no washer, though, I don't think I've ever come across a washer here, but will try with a fairly chunky one. When tightened it pulls the block and box in together so wouldn't think it's the wrong length. Although having gone from 1.6 ('88) to 1.9 ('91) and from BE1 to BE3 It may be hard to find the right one.

 

Sam, are your top bellhousing bolts loose? as it sounds like maybe your 'box has slipped slightly so the threads aren't lining up right. The starter motor bolts will also do this as they aren't long enough and just catch the threads before stripping them (been there)

 

I think I'll order a new bolt from Pug, I'll feel safer reaming this a bit tighter - having overtightened one and rounded the hex before, I'm maybe being over cautious. Stupid bl@@dy design

[t16ryan 1]

are both the dowels in??

[steve@cornwall 100]

are both the dowels in??

 

Good question.......................probably not...............but I guess they soon will be!!!! That would make sense CHEERS

Edited October 13, 2007 by steve@cornwall

[Miles 331 1 Cars]

the thread in the box maybe worn, so giving it a clean and a re-tap might help, I always use thread lock on any car's that get abused as I;ve seen this may times before

[Anthony 1,000]

I threadlock all the gearbox bolts now as I've had various ones come loose - never had any further issues since doing that

[steve@cornwall 100]

I threadlock all the gearbox bolts now as I've had various ones come loose - never had any further issues since doing that

 

For now I've threadlocked in a spare bolt and reamed it quite tight. The tell-tale rumbling feeling and resonant noise has gone (no trouble with gearchanges) So we'll see while I get a new bolt and see how many dowels I have between spare engines / boxes. Some really helpful replies - thanks, guys!

Edited October 14, 2007 by steve@cornwall

[Batfink 201]

and get a torque wrench

[welshpug 1,627]

and get a torque wrench

 

 

naah, FT with the ratchet usually does the trick

 

did you guys ever find out if the dowels were present?

[steve@cornwall 100]

naah, FT with the ratchet usually does the trick

 

did you guys ever find out if the dowels were present?

 

 

90% certain there aren't any in mine I've got a cv boot to do soon so I'll pull the box an inch or so apart (enough to slip in a dowel ) whilst I have the shaft out. Thing is I've also got new discs,pads, calipers and flexis to do so will do together which will be hard to find time to do (daily driver) . While it ain't (too) broke..........

 

Those hex bolts are easy enough to round out with an allen key alone - when you can feel them give, I stop reaming. Too late with a torque wrench or ratchet! A stud, collar and nylock would be great here I think? I do have the right tools for the job, but choose not to use them in this case - after a few years and bad experiences I think it's best to go with your gut sometimes.... 20 yr old castings don't always like manufacturers spec. torque for new bits- eh?- think head studs (no option, but how many break or strip threads) caliper bolts etc...

You need to be a little sympathetic with older cars, after all most are well past their expected service life by now

Edited October 16, 2007 by steve@cornwall

[Rally Slag 0]

hmmmm i had a gearbox bolt fall out at the weekend on the 309, well it may have been a while ago i just never noticed till now, luckly it was laying on top of the gearbox and i was just randomly poking around under the bonnet. It was the top one closest to the bulkhead just under the dizzy. Mine was a 16mm head with a washer on it, quite long. I just put it back in and done it up realy tight with a spanner. I put it down to the group N engine mounts and hard driving, had loads of things fall of since fitting the group n mounts so im used to it now, must be a common thing though

[steve@cornwall 100]

hmmmm i had a gearbox bolt fall out at the weekend on the 309, well it may have been a while ago i just never noticed till now, luckly it was laying on top of the gearbox and i was just randomly poking around under the bonnet. It was the top one closest to the bulkhead just under the dizzy. Mine was a 16mm head with a washer on it, quite long. I just put it back in and done it up realy tight with a spanner. I put it down to the group N engine mounts and hard driving, had loads of things fall of since fitting the group n mounts so im used to it now, must be a common thing though

 

 

Just now had to tighten it again Guess who's checking for dowels in the very near future?

[welshpug 1,627]

it wont take long to check wether the dowels are in place, you can split the gearbox from the engine enough to do it without actually removing the l/h shaft at all (about 3/4" to an inch), you'll need a pair of slim molegrips (pointy nosed ones, or a pair of large pointy pliers) to put them into place if they aren't, then just tighten it all back up.

[steve@cornwall 100]

it wont take long to check wether the dowels are in place, you can split the gearbox from the engine enough to do it without actually removing the l/h shaft at all (about 3/4" to an inch), you'll need a pair of slim molegrips (pointy nosed ones, or a pair of large pointy pliers) to put them into place if they aren't, then just tighten it all back up.

 

That's the plan- but n/s driveshaft needs a new outer boot and the hub is suspected ovalled, too. So seems to make sense to do it all together. Then there's the brake flexis that appear to be perishing - and the new 1.9 discs, pads (mine have done 30K ) and re-manufactured calipers (be nice to paint these before fitting) .................................................. Could be a long day as I really want to only get the tracking done the once.

[jackherer 543]

A mate of mine did 30k+ miles in a 205 Mi16 with that hex bolt sheared off with no gearbox movement at all which leads me to think that as you do have movement you also have another issue causing this. Fingers crossed its the dowels.

[pug_ham 242 3 Cars]

I've just finished putting a new clutch on Ric Handleys Mi today & was shocked at the state when I started taking it apart.

 

Last week Ric said it was making horrible noises when he tried to start it & we assumed it was possibly the starter was dead which we'd intende top replace anyway. (hard to accurately pin point by a pm ).

 

When Ric dropped the car here on Saturday & I started to strip it down to get everything off I noticed a 1/4" gap between the box & block at the back.

 

As I progressed further it turned out that other than the three bolts into the starter there was only one bolt holding the gearbox to the block & that was at the front under the starter.

 

Once it was all apart I started to check the threads in the block & gearbox to see they were OK. The bolt on top of the box at the back of the block was sheared off . How do you shear an M10 bolt?

 

Luckily I got the remains of the old bolt out earlier today & its now back together with two dowels for the box, one for the starter & the correct amount of bolts tightened up.

 

Graham.

[t16ryan 1]

Was there dowels in there to start with??

[pug_ham 242 3 Cars]

There was the usual dowel on the starter & one dowel with no bolt going through it at the back of the block.

 

The gearbox mount was also torn in two.

 

Graham.

[steve@cornwall 100]

DON'T threadlock this bolt without finding out why it's coming loose!!!!!! Without being able to undo itself, mine has just pulled all the threads out of the gearbox I've not investigated the dowels yet, but I guess I'll have a chance when I change the gearbox now :(

[steve@cornwall 100]

DON'T threadlock this bolt without finding out why it's coming loose!!!!!! Without being able to undo itself, mine has just pulled all the threads out of the gearbox I've not investigated the dowels yet, but I guess I'll have a chance when I change the gearbox now :(

 

 

 

OK here we go! Award to Ryan.. no dowels! Top bolt by bulkhead gone! top bolt at front loose. These were all well tight when I did the clutch so I guess the moral is the dowels are definately there for a reason

 

One last Q. the dowel for the starter, is it smaller diameter than the gearbox dowel? couldn't get one in there,

 

 

Managed to get enough space between engine and 'box without disturbing the driveshafts at all, or needing to drain trans. oil to slip the two gearbox dowels into position. I have new pinch bolts and cv boots on order, so more fun later in the week! MOT looming and I had a very uncharacteristic tantrum when the starter just screeched and wouldn't turn over yesterday and have had to fit another bonnet so there's painting to do also. At least it's an auto bonnet

[B1ack_Mi16 67]

OK here we go! Award to Ryan.. no dowels! Top bolt by bulkhead gone! top bolt at front loose. These were all well tight when I did the clutch so I guess the moral is the dowels are definately there for a reason

 

One last Q. the dowel for the starter, is it smaller diameter than the gearbox dowel? couldn't get one in there,

Managed to get enough space between engine and 'box without disturbing the driveshafts at all, or needing to drain trans. oil to slip the two gearbox dowels into position. I have new pinch bolts and cv boots on order, so more fun later in the week! MOT looming and I had a very uncharacteristic tantrum when the starter just screeched and wouldn't turn over yesterday and have had to fit another bonnet so there's painting to do also. At least it's an auto bonnet

 

Startermotor dowel definately a little bit smaller than the gearbox dowels, confirmed.