Exhaust/Inlet Manifold

[esso]

After some advice here,just restored a 1985 Mini-City,its been on the road for about 2 months but it has broke 2 manifolds,it has the standard cast manifold on it and the flange is breaking where the exhaust joins it around the clamp.The car has a Maniflow single pipe exhaust fitted,i`m beginning to think the exhaust is not lined up properly and is straining the manifold.....any ideas?

[MiniGrin]

Do you live in an area with speed bumps, uneven roads or pot holes and so the car is bottoming on the exhaust?

[Bpirie1000]

Does the bottom of the manifold at the y piece attach to the gearbox?
Might be a good idea to have a look and chat with mini sport...

[Phil Hill]

Only things I can think of to check/ensure are : the standard "dog-bone" engine steady and bushes are good and tight, the exhaust joints all fit nicely i.e. don't need to be forced together before clamping them up, the clamp between the down-pipe and the diff housing at the back is fitted and tight.

Add an "ultimate" engine steady between bulkhead and thermostat housing.

Phil.

[DanGT]

Best combination I found was no lower exhaust mount and a good engine steady. I always had problems with the lower mount and was told to take it off. Never had a problem after that.

[esso]

Thanks for the replies chaps,we have already fitted an engine steady to the car.We suspect that the exhaust system is not aligned correctly as the bracket from the downpipe to the gearbox is way out of line.We have removed the exhaust system completely,going to fit another manifold,then the downpipe and then align the rest of the exhaust and brackets to it and see if that helps.

[cone]

Is the manifold clamp a hinged one bolt jobbie or 2 bolt one, if the latter is it the same size top and bottom , years ago I remember people fitting metro ones to a mini and they're smaller top/bottom and thus crack the flange on the manifold .

[guru_1071]

cone said:

fifty years ago I remember people fitting metro ones to a mini and they're smaller .

efa

[esso]

cone said:

Is the manifold clamp a hinged one bolt jobbie or 2 bolt one, if the latter is it the same size top and bottom , years ago I remember people fitting metro ones to a mini and they're smaller top/bottom and thus crack the flange on the manifold .

Good point!,however going to fit a 3 branch manifold now and separate inlet manifold,that better cure it!

[esso]

3 branch exhaust manifold and seperate inlet manifold fitted......sorted!