Exhaust Blow...

[Chris45]

GP500S - 97 model.

Has a slight blow on the exhaust port (underside) which is noticeable when the engine is cold. Sounds acceptable after the engine has warmed up and metal has expanded. No money for a replacement 2into1 so need some ideas for a fix please?

Anyone used metal fillers on such a problem?

PS: It's the joint which is blowing, not the pipe itself

Thnx

Chris
Inverness.
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[mudcow007]

that gungum stuff?

[Chris45]

[Teflon-Mike]

If it is blowing at the head flange, ie the very start of the pipe; then the propper fix is a new exhaust gasket. These are probably only about a quid each, and propper fix by replacement far 'better' than a bodge with gloopy shit! It WILL work for starters, and last.

Niggle is WHY the old gasket is blowing? Old age can see them give up, but, if burned out from a hole i the exhaust, missing baffle packing of after-market 'straight through', your tackling a symptom not the case.

Other niggle and possible hassle is that exhaust studs are wont to rust and or shear. I have had a few that have bee very 'thin' eatn away by corrision, and worse, some that have got so loose that the exhaust flage had worn the threads away as the pipe's rattled, and what was left stripped when owners have tried nippg up the nuts, and stipped what threads remain. Digging in there, I have oft found flanges packed with loads of washers to put the nut on threads that are I presue 'were' still 'good' further from the flange, when the washers were fitted, but corrosion and vbration has wreaked its toll there too.

Horrors may manifest themselves when you dig in.. and seem to get worse....

I would, for the sake of 70p each reccomend buyng a new set of exhaust studs and nuts, so when you have got the exhaust off to fit new gasket, you can clamp them up nice and neatly with least hassle; it's still only a fver or so, certanly less than a tenner, and the 'propper-job' rather than a bodge.

There is risk, when you dig in, that old studs wont play ball, and they are want to shear... BUT they wont get any more inclined to play ball if you leave them there, and gloop up with gloopy stuff!

That's a risk you have to accept, BUT, tackling the job soner rather than later, you do stand better chace that the stud will have more metal and least corrosion, and stand better chance of winding out with a pair of mile grips or a stud=-extractor, and you wont have to get the head drilled and tapped and an over-size stud or helicoil or anything.

And its a done and dusted proper fix; not a bodge, that should 'work' work properly, and not have you having to go back and re-do whilst it doesn't get any better, and leaves you wth even harder time and likely more hassle when yo get round to biting the bullet.

New studs, new nuts, new gaskets, for probably under a tenner... is it really 'worth' going down Halfrauds for a tube of gloopy shit to waste time and money NOT fixing the thing?
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[Rogerborg]

I... urgh... have to agree with Mike. Bodging exhausts tends to be a very short term fix. If it was further down the system I'd suggest silicone sealant (it really does work) but not at the head.

However, I'd start feeding the nuts with PlusGas right now, and blowtorch the heck out of them. If you can get access, I'd consider cutting them off rather than risking a snapped stud. Hacksaw or dremel through the nut towards the head, down the side of the stud.
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[kramdra]

Putty is rubbish, brittle stuff.

Try new gaskets. If that fails then fibreglass exhaust wrap with a hose clamp. I have a largish crack/hose in collector and this has reduced noise to acceptable for the last 10k miles.