Blowing Exhaust?

[puremalt]

My x flow started last night to sound as if the exhaust was blowing everywhere, extremely loud. It now burps & farts on every change , not just on the over run, something definitely isn't right. The sound is coming seemingly from the front around the carbs. The idle is still good- around 900 rpm, if very loud, so I don't think it is the mix. I'm going to check the manifold as after driving on a very bumpy road,perhaps it's got loosened(?) any ideas anyone.

 

Dave Robertson

[ashaughnessy]

I would think it would be easy to diagnose a blowing exhaust gasket (I had one of these just about ten days ago). You'll probably see smoke and gas coming from the manifold joint and you will certainly here it from here. Mine was blowing from one cylinder and it sounded like a VW Beetle.

 

If the throttle linkage has gone out of balance so that one pair of throttles is more open than the others, this can make it sound quite rough (also a bit like a VW Beetle) and noisier and could cause increased pops and bangs. If you run the engine with the bonnet off and stand near, you should be able to hear which side the noise is from and decide if its carbs or exhaust. If it's exhaust the solution is probably obvious. If its carbs, I'd check the throttle balance first of all (assuming you've got one of those carb synchronisation tools that have been discussed very recently).

Anthony

[puremalt]

Thanks.

The mid section of my comp. exhaust has worked loose from the head. One bolt lost, the other hanging on by two threads. Yes it sounds like a beetle/spitfire (Supermarine not Triumph).Course I've lost the gasket too.

Off to Ford Dealer....(groan)

 

Dave Robertson

[DohNut]

Make sure new gasket had hole in middle the same size as the exhaust port, You may have to butcher the gasket to do this. I think that in this months low flying there was a Roger K advert for copper? gaskets, probably the best long term solution.

N

[ashaughnessy]

When I rang a Ford dealer for an exhaust gasket set the other week he reckoned that the gasket isn't available anymore, though he thought it might be possible to get one from the factory.

I got my replacement from Burton power products. I think this is an uprated item and probably has a wide enough hole (though it would be wise to check). It's about a tenner for the set.

Roger King does copper gaskets that are about £20 for the set but he says they are uprated even over the burton type.

 

Anthony

[puremalt]

You're right Doh Nut, the gasket from a motor factor has two separate holes, whereas the shot one is one enlarged oval.

Ta vey much.

 

Dave Robertson

[puremalt]

As I've only just joined I don't have the Low Flying issue with Roger Kings details. Could you let me know as I'm worried now that my pretty butchery of the gasket won't be a good enough seal.

 

Dave Robertson

[Roger King]

The copper gaskets are of laminated construction (in the past the centre layer was asbestos, but these days it's something else). There is a ferrule around each exhaust port hole in the gasket.

 

We have to have these made these days and we had run out, but a new batch arrived yesterday.

 

These gaskets are very good at resisting failure, but you must make certain that the flange of the centre pipes is flat where it attaches to the cylinder head. If it is warped (and this is quite common), there is no gasket available that will last.

 

It is quite easy to remove warping by holding the flange against a belt linisher, or you can even file it flat if you are good.

[david farr]

I recently bought my first caterham, 1700 xflow and have just had a similar problem. The exhaust gaskets had gone and it sounded awful. I replaced them with parts supplied by caterham (a novice mistake?). Things sounded fine until a few days ago when the exhaust started blowing again and I found that the welding where the downpipes meet the 4-1 box had failed. Is this a common problem as the exhaust is only secured at the manifold and the rear bracket, allowing the middle section to oscillate? Any suggestions?

 

Dave

[RIC POPPLEWELL]

BURTON PERFORMANCE OFFER EXHAUST GASKETS FOR THE XFLOW WITH THE CORRECT SIZE HOLES......WHY DO CATERHAM SUPPLY ONES WITH HOLES SMALLER THAN THE PORTS??? MUCH BETTER, ALMOST PERFECT LOW END PICK UP WITH THE RIGHT ONES. THEY ARE VERY CHEAP FROM BURTON SO JUST CHANGE THEM EVERY SO OFTEN. CAUSE USUALLY THE ALIGNMENT OF THE EXAHUST MANIFOLD AND IS VERY COMMON.HOPE THIS HELPS.SORRY ABOUT ALL THE EDITING, DAMN NOVICES................................

 

Edited by - RIC POPPLEWELL on 26 Apr 2002 16:46:59

[RIC POPPLEWELL]

 

 

Edited by - RIC POPPLEWELL on 26 Apr 2002 16:45:58

[RIC POPPLEWELL]

 

 

Edited by - RIC POPPLEWELL on 26 Apr 2002 16:45:08

[RIC POPPLEWELL]

 

 

Edited by - RIC POPPLEWELL on 26 Apr 2002 16:44:46

[RIC POPPLEWELL]

 

 

 

 

Edited by - RIC POPPLEWELL on 26 Apr 2002 16:49:38