Fuel pipes .. puzzled

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Ya5
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Post Mon May 05, 2014 9:33 am

Hey all .. Got hold of a very clean coupe shell its an E reg.
I believe it was 1.6 originally ( I got shell without engine ).
Looking at dropping M20B25 into it.

Just looking round noticed there is only on fuel pipe coming from rear of car to the engine bay :?

Would this be because it was originally carb setup ?

Any suggestions on what to do ?
Do I have to run a new second pipe from engine bay to rear ?
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Brianmoooore
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Post Mon May 05, 2014 9:58 am

It would have been a 316 (not 316i) which had a 1.8 carb. M10 engine.
You will need to run the second fuel pipe, and connect it to a two pipe in tank fuel pump, and the fuel pump wiring will possibly be missing from the rear under car wiring loom.
If you have the fuel tank that came with the shell, check whether it has the cup welded inside the bottom of the tank, for the fuel pump pick up to sit in.
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Ya5
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Post Fri May 16, 2014 12:35 am

Thanks for the info Brian...
Just to clear it up, having a slow day sorry, I'm going to remove the second pipe along with the fuel pump from doner car and is it just a simple matter of putting pipe in and fuel pump and just plumb it together ?
The shell tank doesn't have cup in the tank either.
Thanks
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Brianmoooore
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Post Sat May 17, 2014 2:04 pm

If the tank you use doesn't have the cup under where the pump will fit, then you'll get fuel surge when the tank gets low on fuel.
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Ya5
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Post Mon May 19, 2014 1:52 pm

Brianmoooore thanks for the help :-)
Got it sussed and found the wiring already there too ( wasn't looking hard enough )
Will I need to add a relay / fuse for the fuel pump ? As it is pre wired already.?

Thanks again
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Brianmoooore
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Post Mon May 19, 2014 2:25 pm

The relay will be part of your new B25 engine loom. It fits, along with the DME and lambda sensor relays, on a bracket which is part of the AFM mount which you will need to fit on the LH inner wing of your car.
The fuse is probably missing - it's #11 and should be a brown 7.5A one.
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Ya5
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Post Thu May 22, 2014 7:12 pm

Everything you mentioned is there. All fuses and relays are in place.
When trying to start car from ignition the replays click and that's all.
The starter does not turn at all.
When shorting the starter out ( screw driver method ) the starter spins.
Its like the starter is not engaging.

Just off the key nothing happens :-/

Any idea.. so close now ... :mad:
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Brianmoooore
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Post Thu May 22, 2014 7:28 pm

Sounds like you have the smaller wires on the starter motor wrongly connected.
Is your 2.5 engine pre or post facelift?
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Ya5
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Post Thu May 22, 2014 7:46 pm

Wires I checked and look fine. Took photo before removing them and look the same configuration.
Engines is 2.5 from pre facelift mate D reg cab.
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Brianmoooore
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Post Thu May 22, 2014 9:38 pm

Does your shell have a 20 pin round C101 engine loom socket?
If so, what colour are the wires going to pin 15 and to pin 18?
What colour wires on the same pins of your engine loom plug?
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Ya5
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Post Fri May 23, 2014 2:19 pm

Yes has the C101 ..

Shell loom Pin 15 has nothing. Pin 18 is Black/Yellow

Engine loom Pin 15 has nothing. Pin 18 Black/Yellow


Does Pin 15 need wiring ?

Thanks
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Ya5
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Post Fri May 23, 2014 11:31 pm

Plot thickens :roll: Had another look at starter today after removing it noticed that I had the smaller/thinner wire on the wrong lug on starter :o:
Didn't notice the lug on bottom as couldn't see it.
So now car turns over, fuel looks fine, just doesn't seem to be a spark?
Is there some wiring issue still regarding the C101 ?

Thanks for help so far :)
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Brianmoooore
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Post Fri May 23, 2014 11:41 pm

There was a change in the way the unloader relays (K5 and K7) are operated when the engine loom changed from pre facelift to post. Facelift has a wire on pin 15 of the C101, but both halves of yours appears to be pre, so that's not the problem.
The 'facelift' extra wire ends up on the starter motor, probably to the extra terminal you have discovered.
Fuel pump working without sparks is unusual, and won't be anything to do with the C101.
Are you absolutely sure the fuel pump is running when you crank the engine?
Connect a 12 volt bulb between the + terminal (green wire) of the ignition coil and a good earth, NOT the other terminal of the coil, and confirm that the bulb lights when you switch on the ignition, and stays lit when you crank the engine.
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Ya5
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Post Sat May 24, 2014 11:37 pm

Ok that explains the vacant pin 15. Does it seem like I've got starter from a facelift on mine.
Had another set of eyes to give it a look over. Don't ask, ( was having a brain fart day ) but I do have spark :roll:

Should have mentioned this earlier I guess if it helps... :roll: Engine while removed has been completely stripped down and all parts cleaned and painted etc and put back together.
Everything has been put back as it should.

Found the crank sensor connectors were green and oxidised so these have now been cleaned up too.
I've cleaned all grounding points on engine and chassis, so earth is good.
I have fuel flowing, spark is good.

Engine seems to start an fire for split second, kinda splutters and then dies.

Does TPS have any involvement in firing engine?
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Brianmoooore
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Post Sat May 24, 2014 11:55 pm

An E30 should be started with your foot clear of the accelerator pedal, so that it starts on the idle map, and a duff TPS will mean it starts on the run map. This shouldn't make any major difference however.
An engine that fires, splutters and dies may indicate a duff fuel pump that is failing under the reduced voltage it gets when the starter motor is working.
Power the pump up with a separate battery connected directly to it and see if that helps.
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Ya5
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Post Sun May 25, 2014 7:44 pm

Found a little problem today, the "fuel damper" ( think that's correct name ) which comes just after the fuel pump underneath had three pin holes due to rust and was losing quite abit of fuel at this point.
Have removed this and just connected fuel pipe up.

Have got a booster pack on too, car splutters for 1-2 seconds occasionally and dies, other times just keep on cranking and it kinda is trying to start, but no go :(

I didn't get time to wire fuel pump direct to battery today, but will do tomorrow.
Would this still be an issues even with the booster pack connected too ?

Thanks for the help and suggestions, finding my way round these engines is a lesson itself everyday :mad:
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Brianmoooore
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Post Sun May 25, 2014 7:57 pm

What fuel pump do you have in this car? Damper was only used with the ancient external pumps.