You mean for the crank / top end area?
It must be difficult to seal up the gearbox / transmission area? It's not airtight anyway?
Dye Penetrant testing
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B-Race Tuning
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It should be air/ oil tight once the breather is sealed (thats the reason the breather is there).
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mick1
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A top end leak test would require the crank seal to fail to allow air into the gearbox. The weld looks fine and the gearbox area isn't under a great deal of pressure as the breather allows air to escape. Personally i'ld just got for it.
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rosscla
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Yes but it's not intended to be under normal operation, hence the breather and shouldn't run under pressure otherwise one of the seal will eventually blow.B-Race Tuning wrote:It should be air/ oil tight once the breather is sealed (thats the reason the breather is there).
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bryansmudge
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Get the test done or get the gear and do it yourself, 1 tin of dye, 1 tin of cleaner and 1 tin of developer. Clean area with the cleaner, apply the dye, clean off the excess then cover in developer - wait and see if the dye is drawn back from the crack/ weld area into the developer. Easy enough to do, not so easy getting the dye of yer mits. The engineering shops wouldn't charge much if anything at all for this I wouldn't think.
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B-Race Tuning
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if you seal the crank bearing area and fit a gasketed chaincase, use the breather hole as your filling point then it will be 'gearbox end' not 'top end' sealed. I know it's not supposed to be under pressure, hence breather. But, hot oil WILL find is way out with no pressure through gravity/ capillary action. putting under pressure and warming with a heat gun should give you the peace of mind it's crack free/ fully repaired (looks a reasonable job though).
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B-Race Tuning
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I can't open pictures but a leak is a leak, small or otherwise. It's surprising how thin sae90 gets once hot, and surprising how big a small leak can get once the casings get hot. Get it carved out and welded. Simon.
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B-Race Tuning
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I've just been tracing/ tracking an air leak around the welding I did on a T5 casing that's been converted to the LML reed intake. It was easy to find the "out" side of the leak (it was in the clutch housing area) but a pig to find the "inlet" side of it. It was from the locating screw hole used to hold the original T5 carb box (that then becomes redundant) + porosity in the casing/ weld. Yours does look relatively easy to do from the outside, requiring no further machining. Definitely worth doing for what it'll take/ cost (negligible). Simon.


