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Re: Fueling too rich, 2.5 Pi
Posted: Wed Jan 04, 2017 11:58 pm
by KieranEbbett2500
I thought so and looking at the list of cars you've got there you'd probably be the one to know!
At the moment it uses a lot more. So I want to get it sorted asap so I can enjoy running the engine in
Re: Fueling too rich, 2.5 Pi
Posted: Thu Jan 05, 2017 3:24 am
by tony
O.K. I'm in Wairoa but won't be any help to you.
We have a Club based in Hastings. Hawke's Bay British and European Car Club. Google it and have a look. We have a lot of Triumph members. Steven Tidswell our Club Captain is an ex Triumph mechanic and has a lot of knowledge. May pay to contact him direct rather than go through party.
Tony.
Re: Fueling too rich, 2.5 Pi
Posted: Thu Jan 05, 2017 3:28 am
by tony
I see Steven is not on the contact list, but email Sue.
Tony.
Re: Fueling too rich, 2.5 Pi
Posted: Thu Jan 05, 2017 5:09 am
by KieranEbbett2500
Have sent an email to Sue.
Re: Fueling too rich, 2.5 Pi
Posted: Thu Jan 05, 2017 9:33 am
by KieranEbbett2500
Spoke on the phone to him.
As I expected there wasn't a lot he could do without any test equipment for vacuum and fuel pressure etc. But he's gonna have a ring around and see what he can come up with.
Re: Fueling too rich, 2.5 Pi
Posted: Thu Jan 05, 2017 5:12 pm
by Alec
Hello Kieran,
"I've tried a few things but it all still points to fueling issue."
A Lucas P.I. will always run rich if the engine is not 100%, anything that affects the manifold vacuum so that it is lower than it should be gives a richer mixture.
If you are sure the engine is 100% then the metering unit can be removed and sent to someone with the right equipment to check the calibration.
Alec
Re: Fueling too rich, 2.5 Pi
Posted: Fri Jan 06, 2017 9:41 pm
by KieranEbbett2500
A bit of an update.
I removed the air cleaner to look at the butterfly synchronization and discovered they weren't quite right. The rear most two weren't opening until about 1500 rpm (which would explain the hesitant running below that engine speed) and the middle two weren't quite closing at idle. Which explained why it would idle with the air bleed screw wound in. It is a large amount better but is still running richer than I would imagine it's supposed to. I'll. Try and get a hold of a vacuum gauge and one to test the fuel pressure once all of the mechanic shops reopen next week. A fellow in town apparently has all the tooling from the Triumph agent that was there many years ago. So hopefully I'll have a bit of luck with it
Re: Fueling too rich, 2.5 Pi
Posted: Mon Jan 09, 2017 3:10 pm
by Mike Stevens
If I remember correctly, the MU signal comes from the middle pair of inlets, so if that pair aren't closing properly, the MU is likely to see a lower that normal 'vacuum'. (Strictly speaking it's 'manifold depression' rather than 'vacuum', but the latter is quicker and easier to type!).
In my experience, the PI system can be be made to run very well indeed, but the condition of the engine, and it's setting-up (adjustments, timings etc) are far more important than with a carb engine.
It sounds like you are nearly getting there!
Cheers,
Mike.
Re: Fueling too rich, 2.5 Pi
Posted: Sun Jan 15, 2017 7:15 pm
by KieranEbbett2500
Since my last post ive retorqued the head down and readjusted the valve clearences.
The car is going well now with just more than 600kms since the rebuild.
Im pretty much stuck with progress on it until i pay the machine shop for thier work.
I really am on the lookout for test gauges and knowledge of somebody in New Zealand who can reset my metering unit.
Re: Fueling too rich, 2.5 Pi
Posted: Sun Jan 15, 2017 8:28 pm
by Alec
Hello Kieran,
you can buy pressure gauges and vacuum gauges from industrial sources, something like a 0 - 150 psi pressure gauge, preferably silicone damped, but that is not essential and a reasoanbly large diameter vacuum gauge. You will then need a suitable short high pressure hose with eth correct fittings. Try a hose replacement service that produce hoses for hydraulic devices, e.g. diggers etc.
Alec