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[Last Triumph]

[Last Triumph]

I'm still trying to find the cause of my poor running when cold and having changed and replaced pretty much everything in the entire system now, including the inlet manifold gasket this afternoon, I suddenly noticed that the exhaust was leaking a little - when I say a little, enough to keep it running with the tailpipe completely sealed off!

I need to trace the leak but in the dark with a torch the source of the leak was not conclusive, so I'll have a better look tomorrow - but it got me thinking...

Could leaking manifold to head gaskets cause poor running when cold that gets better as things heat up and expand and perhaps seal a gap?

I'm probably clutching at straws, but thought I;d ask if anyone has experienced this before regarding running issues related to exhaust gaskets issues?

If it does turn out to be manifold to head gaskets that are leaking - are there any tips to getting the manifold off - I can already see issues gaining access to the lower row of bolts 'under' the manifold. I assume it's alternator off and a scraped knuckles and forearm?

[Last Triumph]

Found the leak - it's at the joint between the manifold and down pipe and is substantial.

I have already replaced the gasket and made sure the old gasket had been fully removed and that the sealing surface of both parts were smooth.

I just cleaned everything up again and re-made the joint being careful to torque the bolts down evenly and tightly, using copper grease on the nuts to ensure a smooth and bind free tightening sequence.

Fired it up, still leaking, jut in a different place and just as badly.

I didn't use exhaust paste as I shouldn't really need to, plus the area between the hole and the outside edge is so thin, I suspect it'd blow through in no time anyway.

Any clues?

[morghen]

Cant remember how the NA looks there, but should it have a crush ring of some sort? if not, properly torqued the nuts?
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Supercharger and EFI kits
https://www.the924.com

[Last Triumph]

Just thought I'd bring this one to a close having now finally cured it.

I can't honestly say it was one thing in particular, more just a series of incremental improvements that made a difference in the end.

Interestingly, curing an exhaust manifold gasket leak made a fair bit of difference.

Replacing the inlet manifold gasket also made a difference.

The final change was that I adjusted the AAV so in the cold position it was a little more open than it had been previously. It took some experimentation to get right but I've had it though several heat cycles and it's now settled where I want it.

The water pump bearings were goosed, so with that replaced and the exhaust manifold leak corrected, it's now much quieter and smoother sounding.

If fires up from cold instantly, settles to an idle speed of 1,000 rpm before falling back to about 950 rpm when fully warmed up.

Here's a stone cold start to demonstrate....

http://www.volkszone.co.uk/VZi/showthread.php?p=15838073&posted=1#post15838073

I'm calling that fixed.

[brian19600]

Nice! The 16 pages have been an enjoyable and informative read.
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78 924

[ideola]

Congratulations! What a saga! What determination!
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erstwhile owner of just about every 924 variant ever made

[peterld]

Bravo Sir! I salute your tenacity.
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80/81 932/8 ROW