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MFI Cold Start T Piece
Posted: Wed Feb 09, 2022 7:10 pm
by fcd911
Hi
I need the nylon T that splits the cold start fuel feed pipe between the left and right injection stacks.
I have looked on the 1970-73 PET but it does not seem to be shown on the diagram or in the parts list.
I have a horrible feeling these are NLA anyway, in which case what is the alternative?
Thanks in advance
John
Re: MFI Cold Start T Piece
Posted: Wed Feb 09, 2022 8:19 pm
by markm
Re: MFI Cold Start T Piece
Posted: Wed Feb 09, 2022 8:40 pm
by fcd911
I have now found the part / number on the PET - I was looking in the Fuel section but it is within the Engine section
Part No: 999 137 005 40 (Part 46 in Illustration 107-30)
Rose Passion seem to have them
https://www.rosepassion.com/en/entry-re ... one_saisie It looks a rather innocuous part.
Is it possible a Windscreen Washer Tube T may do the job although the part number for these is different, there may be a fuel / heat compatibility issue!
John
Re: MFI Cold Start T Piece
Posted: Wed Feb 09, 2022 9:31 pm
by Nine One One
Dependant on whether you want originality or not, there are plenty of ’T’ pieces on Ebay, including brass ones if Ethanol could be a problem?
https://www.ebay.co.uk/itm/254418387114 ... SwRu5dycjK
Re: MFI Cold Start T Piece
Posted: Thu Feb 10, 2022 7:22 pm
by fcd911
Sorted thanks for the steer to eBay
I find sourcing small low value items on eBay an absolute pain there is so much to wade through, so many sellers chasing the same (tiny) market and I lose the will to live. However I think I have found the right product.
https://www.ebay.co.uk/itm/283884761704 ... Sw6aZexU64
I did not want brass for a number of reason but not hung up on originality for the rally car. I think these fit the bill and actually mention use with fuel.
Have order 4 (2 packs) I felt guilty just order 1 pack with free post.
John
Re: MFI Cold Start T Piece
Posted: Fri Feb 11, 2022 9:33 am
by gridgway
Is this for the fuel squirters? Do you need to run them in a rally car? They scare me, but I'm easily scared

Re: MFI Cold Start T Piece
Posted: Fri Feb 11, 2022 12:08 pm
by fcd911
Yes Graham, the pipe that squirts neat fuel from the Cold Start Solenoid into the Injection stacks when the engine is cold and turning over.
Not too scary as long as it is maintained OK - the Solenoid is operated by a feed from the Starter Motor Solenoid via a Thermo / Time Switch so it only opens (and squirts fuel) when the starter is turning and the engine is cold – in theory.
The “current” T piece was a piece of copper pipe which had been half cut through and bent to open up the cut and another bit of copper pipe had been soldered onto the cut to make a Y – it fell apart in my hands – that was scary
Try telling the engine it does not need the extra squirt of fuel at 6.00 in the morning and it is 3 degrees outside
John
Re: MFI Cold Start T Piece
Posted: Fri Feb 11, 2022 12:47 pm
by gridgway
I'm sure you are right about the need on a cold day and it being fine as long as it doesn't malfunction!!
I'm just transplanting a 2.4S motor into my 911 from 2.0 on carbs and haven't decided whether to get the squirters wired in yet.
Re: MFI Cold Start T Piece
Posted: Fri Feb 11, 2022 2:14 pm
by hot66
Never had a problem in almost 20 years .. on the 2.4 cars the design was improved over previous and they are fine when injected straight into the throttle inlets
I thought these were N/A too ? theyre not just a t-piece or 90deg piece though as they have the injection squirter hole
Re: MFI Cold Start T Piece
Posted: Fri Feb 11, 2022 3:50 pm
by jwhillracer
gridgway wrote:I'm sure you are right about the need on a cold day and it being fine as long as it doesn't malfunction!!
I'm just transplanting a 2.4S motor into my 911 from 2.0 on carbs and haven't decided whether to get the squirters wired in yet.
It's worth having them wired separately to a push button on the dash. If you're driving it hard and stop, the squirters give enough fuel to start the engine when the engine heat produces a vapour lock in the injection pump.
It saves the embarrassment of waiting 1/2 hour for everything to cool before it will start again.................
Ask me how I know
JW
Re: MFI Cold Start T Piece
Posted: Fri Feb 18, 2022 3:42 pm
by camperco
No, you cannot use a screen washer T piece. The correct item has an orifice to control the fuel flow into the air inlet and the diameters are different to washer pipe. Don't use fish tank fittings either.
We know someone who does use screen washer bits for this job and thanks to them, combined with some some other errors such as shoddy wiring and the MFI belt rubbing the fuel line, the engine caught fire.
Re: MFI Cold Start T Piece
Posted: Fri Jun 03, 2022 7:46 am
by g3ngs2
Bringing this back up to the top (as it recently has become relevant having spotted a split in one of the pieces) if the generic T or Elbow pieces aren't the answer what is?
Rummaging on Pelican / Early 911 looks pretty inconclusive and what you seem to turn up is
http://www.autoatlanta.com/porsche-part ... ion=107-30
Group 12 the collection of elbows and T pieces are NLA
Or the brass ones - which whilst they look lovely are also an uninspiring £160+ for a set per side
Re: MFI Cold Start T Piece
Posted: Fri Jun 03, 2022 12:24 pm
by fcd911
Well up to now the T Piece, purchased off ebay, is still behaving perfectly. I have just checked it before posting this and there is no sign of deterioration
I went on my original posted link but that original link no longer worked, back tracking on my order the seller seems to have updated the listing.
Try:
https://www.ebay.co.uk/itm/283884761704
It does say suitable for petrol and diesel so even as a temporary measure it has to be better than a split T piece.
John
Re: MFI Cold Start T Piece
Posted: Fri Jun 03, 2022 3:31 pm
by g3ngs2
Thanks John.
Good to know it's lasted.
I've a split in one of the Ts so on the crossroads of replace one, them all, and if all to go your route or brass.
(Brass is the least attractive as £320 is nuts).
Sent from my SM-G950F using Tapatalk
Re: MFI Cold Start T Piece
Posted: Fri Jun 03, 2022 8:51 pm
by gridgway
What about brass ones from eBay?