Manifold leak checking..

[igiveup]

Just wanted to try something. My N/S is blowing and reading the http://www.chimaerapages.com/technical-info.html Exhaust leak testing section I'm wondering of the following would do the same job OK?

I'm thinking of the following:

1 Old bicycle inner-tube cut in half opposite side of valve.
2 Both ends over each exhausts , taped up if need be.
3 Electric Car Tyre pump to provide air to valve
4 Listen with a length of old Hose pipe.

I'm guessing this will work just as well, i'll use a low Psi

[chimyellow]

When doing this you could also use a washing up mixture and spray it onto the join. Any leak should show up as a bubble 'beard'

[igiveup]

chimyellow said:

When doing this you could also use a washing up mixture and spray it onto the join. Any leak should show up as a bubble 'beard'

Oh yeah, forgot to add that bit, doh.

but my "Heath Robinson" idea is sound?

[phillpot]

If engine has stopped with any of the cylinders in the "valve overlap" position won't air will leak through and out of the airfilter?

[igiveup]

phillpot said:

If engine has stopped with any of the cylinders in the "valve overlap" position won't air will leak through and out of the airfilter?

I'm sure this will not be an issue?

As pushing air from back to front, only listening to air coming out manifold area.

I could be wrong.

[phillpot]

igiveup said:

I'm sure this will not be an issue?

May well not be if you have a reasonable air supply, but just pointing out it won't be a closed loop?

could always remove air filter and bung up with a big rag?

[Isitme]

This method has often been quoted on here: Take 2 tennis balls, shove one up one pipe to seal it, make a small hole right through the other ball so that a compressor airline quick release connector will push-fit into one side of it and air will escape from the other, and shove this ball up the other pipe. Connect the compressor, switch on and listen at the manifold.Use washing-up liquid or a strip of paper as a tell-tale to pinpoint the leak.

[J400GED]

Why not try: cut a length of garden hose and, with the engine running, put one end to your ear and then point the other at various parts of the manifold? You will be able to notice the difference in sound when you get to the leak point.

[Mr Supercharged]

The fairy liquid 70% water 30% mix brushed over the manifolds with a paint brush and compressed air up the exhaust is by far the best way of pinpointing the exact location. I removed the plenum hose and blocked up with strong tape in addition to blocking off the other exhaust pipes. Need to make the compressed air gun seal in the exhaust pipe too.

[igiveup]

Thanks for all the advice, I'll remove intake upvto AMF and block it up there.

[QBee]

My TVR expert uses Ged's method.

In his case he uses rubber tube a la gas barbecue, with a short length of thin copper tube in the end to make it heat proof. Other end in his ear, point the copper end at various points around the manifolds.
I have listened and it works.

You could also make sure your manifolds are nipped up tight.

[stesrg]

Now here's the easy way !! Get some gas leak detector get someone to start the car from cold quickly spray on each bank and the one that bubbles is leaking ? :-)
Yep tried it the other day .
Left hand manifold coming off tomorrow as someone has fitted wrong gaskets by the look of it !!
Ste.

[ianwayne]

I found a method I read on here worked for me.

Tape a feather to the end of a pencil and lower towards each manifold joint with the engine idling. Mine fluttered a little at a couple and a lot at the obvious noisy one. When iI had them done, most of them were shot.