exhaust keeps falling off!

Post by **benno** » Tue Jul 24, 2007 9:24 pm

A standard exhaust and manifold, clamped well and a good coating of fire gum, so why does it keep coming loose. Litteraly every week it comes off and I can't see how. Am I just being a muppet or what

Post by **bmcecosse** » Tue Jul 24, 2007 10:43 pm

The manifold may be erroded away - or the clamp may be useless. Best to use 2 bolt type - rather than 1 bolt + hinge type. Only a smear of paste should be used - and crank the exhaust pipe into place witha jack under - then fix the clamp. Also - look to the engine mounts - are they knackered ? And the engine steady bracket - has it sheared away from the bodyshell? And are the exhaust system supports in good order - flexible, but not too flexible ?

Post by **moggyminor16** » Wed Jul 25, 2007 7:16 am

i would also say as i found if you use the 2 bolt clamp (a lot better one ). once you have put the nuts on the bolts get 2 the same and lock the over nuts in place this will stop any thing vibrating lose as they do

Post by **dunketh** » Wed Jul 25, 2007 10:43 am

New clamp needed.
I went for 2 years with the same problem - used to faithfully re-fit it at least once a month!

The clamp will actually stretch around the manifold joint making a super-tight seal.

Old clamps dont do this - they just but up either end and hold it 'tight' but not super tight.
It needs to be 'super' tight.

Post by **rayofleamington** » Wed Jul 25, 2007 5:36 pm

The 2 bolt pressed steel clamps are good, but I prefer the cast type as they are even more rigid.
Your exhaust manifold is now going to be useless - as the exhaus swings around it will wear the manifold sealing face and you may really struggle to get ti to work properly unless you replace the manifold.
Also make sure you have enough exhaust support straps - there are supposed to be 3! Many cars jusat have one at the rear but the ones at the front are usefull to reduce the load on the manifold clamp.

Also make sure that your engine top steady is in place and working. If it's missing, the engine will move much more and this will reduce the life of the manifold joint.

Finally - if your gearbox is rough or if your propshaft is badly out of balance, these vibrations can have a bad effect on keeping anything tight!

Post by **dunketh** » Thu Jul 26, 2007 9:32 am

3 straps?

I have one under the rear passenger area and one at the back of the car - thats two. Wheres the third meant to be?

Post by **rayofleamington** » Thu Jul 26, 2007 7:07 pm

I have one under the rear passenger area and one at the back of the car - thats two. Wheres the third meant to be?

As far as I know (I'm no concours expert!) there should be one one front footwell, one before the exhaust goes over the axle and one at the rear end. I've seen them like this but can't guarantee that the front one was factory fit - none of my Minors have been in nearly new condition - most were basket cases

Post by **bmcecosse** » Thu Jul 26, 2007 10:07 pm

Only have - and have ever seen - the two supports.

Post by **JimK** » Thu Jul 26, 2007 11:25 pm

My '65 2-door only has the two, but several people have told me that another under the rear of the engine bay can prolong the life of the manifold/exhaust join.

Post by **bmcecosse** » Thu Jul 26, 2007 11:38 pm

I doubt it - the exhaust system needs to move with the engine. A support from the engine to the exhaust downpipe would make more sense! This is VERY necessary on Minis to secure the exhaust to the engine unit - surprised it's not done more often on Minors.

Post by **bigginger** » Thu Jul 26, 2007 11:41 pm

It sounds pretty similar to the LCV arrangement though.

Post by **dunketh** » Fri Jul 27, 2007 9:28 am

I have the two as mentioned but have since put a third one in myself.
Its just another hanger strap, bolted through a spare seat retainer nut under the passenger side.
It still allows the exhaust to move with the engine but takes the some of the weight of the system off the manifold joint.

The third mount: