Attention: Analytical Minded 75/ZT Techies. Amateur Diagnosis incoming... :-)

[Abott10]

Decided to get my MG6 Engined MG ZT-T 1.8T running and off SORN.

Previous owner drained tank of several gallons of fuel via the In-Tank Fuel Access Panel. So one of the first tasks was to reassemble that which was in a bit of a state. Sometime later with original headless engine removed and MG6 engine in place, started MG6 engine and ran it for a few seconds to confirm it was a runner. Very hesitant to start but, fired up after a few seconds. Started occasionally in the meantime and again hesitant or non-start. When start failed got it running by squirting a few drops of RON 75 into the Inlet Manifold via the Brake Servo Vacuum Tube take off. That results in immediate start. Past couple of days, I have completed 99% of the reassembly of all removed parts and charged and bled the cooling system with 50-50 OAT Coolant. It did start then but again only with a squirt of RON 75 into the Inlet Manifold. Engine then runs smoothly and warmed up nicely with strong heater output too. Always a good sign that for me.

Then, on fully warmed engine switch off, car would start immediately every time whilst warm. However, if left to cool, it would not start only with a squirt of fuel.

So based on this scenario which has been happening over the past few days, I think that any residual pressure in the fuel lines in the warm engine will enable the engine to start every time. When allowed to cool say overnight, needs a squirt of RON 75 to start. So it looks like the fuel pressure is being lost as the engine cools.

So, a quick look into the In-Tank Fuel Filter will be necessary. Which as far as I know was the only part disturbed when removing the fuel previously by the then owner.

So, have I correctly identified the problem is the In-Tank Filter needing attention or, is the Fuel Pump the guilty party here?

In any event, I will disassemble the In-Tank Filter and fit a new large O-Ring and Clip. If that does not do the trick then The Pump may be the guilty party after all.

Any thoughts on this will be appreciated before I look at the Fuel Supply issues more closely.

Thanks in advance.

[kaiser]

I would certainly pay attention to the fuel delivery system.
Sounds as if something might be leaking on the suction side, could be a union or maybe the filter lid.

Might be related to the emptying of the tank by previous owner.
But it could be coincidence.

[roverbarmy]

Have you tried clearing any fault codes and re-reading after an attempted start?
Mike

[Greeners]

From My recent fuel experiences on my Turbo, its very easy to get the filter assembly back together incorrectly. The O ring must be in the right place to seal and lock together correctly

Don't forget to fit the clip as well

[Lovel]

When you fit o-ring make sure it does not roll or extrude. Use silicon grease or similar to fit.

Rather than all this guessing why not check the fuel pressure reading from the Schrader valve on the manifold. The cost of the gauge is pocket money

Here's my experience. I still reckon a stainless self tapper is better than the orange plastic clip.

http://www.the75andztclub.co.uk/foru...5&postcount=20

[T-Cut]

It might be what I call incipient FFS. The filter module leaks just enough to inhibit starting from cold, but once started (using an independant fuel), the engine runs. I suspect it would be problematic to actually drive at any speed. Don't know if you tried that. I'd suggest that any work done on the filter module, even lifting it so far out of the tank is enough to cause slackening, especially if the forces causing it have been acting positively for some time. My gut feel is this will resolve when you fit a FOC. I'd also agree about renewing the rubber oring, which will probably have dried out during the long stand without fuel

TC

[Billyuk1]

hi john,
it might be worth replacing the fuel filter while you are in there.
i have done a lot of reading on the subject and had good reply's from forum members on hear.
i ain't got around to taking my tank units out yet to fix my faulty fuel gauge due to a bad back.
i think the Mini Cooper (R50/53) uses the same system as our 75's / zt's
hear is an interesting article you might find usefull regarding the fuel filter unit.

http://www.billswebspace.com/MiniR50...erDIYGuide.htm

also i bought a replacement fuel filter that i intend to fit from ebay.
not a bad price for the full kit inc seals..

http://www.ebay.co.uk/itm/3716080828...%3AMEBIDX%3AIT

[Greeners]

If you use the mini cooper filter kit, the O ring is fatter and won't fit.

[T-Cut]

Originally Posted by Greeners

If you use the mini cooper filter kit, the O ring is fatter and won't fit.

I guess BMW realised the MGR module is prone to cap leakage and modified the joint. A thicker o-ring suggests a different screw thread/bayonet pitch is used for holding the body and cap together. My understanding is MINIs don't suffer FFS (?). Does anyone know for sure?

TC

[Greeners]

Originally Posted by T-Cut

I guess BMW realised the MGR module is prone to cap leakage and modified the joint. A thicker o-ring suggests a different screw thread/bayonet pitch is used for holding the body and cap together. My understanding is MINIs don't suffer FFS (?). Does anyone know for sure?

TC

Ive Got a mIni Cooper R53 project at present, If I get a moment I'll check