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iain
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Sold the turbo and seeing what the C20XE can do!

Near Lincoln

My car will only run for about 30s hard driving, i dont know why.

So far ive checked fuel pressure, change the dizzy/coil etc, checked the voltage to the coil, changed the carb and still no joy.

Guessing its something simple as its only just started doing it but cant think what. It seems like its running out of petrol but the pressure never dips when it cuts out.

Maybe a float chamber problem? Only thing is ive changed the carbs so that would be strange if it was.


iain
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8506 Posts
Member #: 16
Sold the turbo and seeing what the C20XE can do!

Near Lincoln

My car will only run for about 30s hard driving, i dont know why.

So far ive checked fuel pressure, change the dizzy/coil etc, checked the voltage to the coil, changed the carb and still no joy.

Guessing its something simple as its only just started doing it but cant think what. It seems like its running out of petrol but the pressure never dips when it cuts out.

Maybe a float chamber problem? Only thing is ive changed the carbs so that would be strange if it was.


FesterTurbo

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Check your fuel filter. Know someone who had this problem on a Mini Pickup and the standard filter got blocked. Most people remove them I think.


FesterTurbo

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Check your fuel filter. Know someone who had this problem on a Mini Pickup and the standard filter got blocked. Most people remove them I think.


AlexB
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The boring bloke who runs this place.

Berkshire

Thinking about it, Fester might be right, when I first got my mini, it kept dying on the way home, because loads of crap from the tank was clogging up the carb. (it didn't have a filter) - it felt as if it was just letting go..

I'd give the entire fuel system a check over -- loads of stupid little bits to check.


AlexB
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The boring bloke who runs this place.

Berkshire

Thinking about it, Fester might be right, when I first got my mini, it kept dying on the way home, because loads of crap from the tank was clogging up the carb. (it didn't have a filter) - it felt as if it was just letting go..

I'd give the entire fuel system a check over -- loads of stupid little bits to check.


turbodave16v
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SouthPark, Colorado

Awight,

By the sound of it, you have a fuel pressure gauge connected, such that you can see the fuel pressure gauge whilst driving, and this is as it should be (3-4psi at tickover, rising to around 10psi whan at boost transition point - Zero on the gauge - and rising proportionally with boost thereafter) then you can discount the pump or regulator without question.

I will also assume you have the anti-run-on outlet tube blocked. I personally suspect an ignition problem - despite you changing the dizzy already.

To check, get yourself a nice small 12v bulb of no more than 2w (a gauge illumination bulb is ideal). Connect a simple switch to it, and two long wires, so the bulb can be taped to your dashboard, and the ends of the wire can reach your coil and dizzy.

To start with, connect the wires across the + & - of the coil. At tickover, the lamp will be seen to be flickering quickly, but consistently. As you increase the revs, it flashes much quicker, and from a distance, just appears to get brighter up to around 3500 rpm. From then on, it seems to be permanently on bright.

If the bulb flickers when the engine cuts out or loses power, It IS an ign problem.
If it stays on, maybe dulling as the revs drop, it is NOT related to the ign system, short of the plugs, leads, cap and rotor arm.

You need to isolate this first - assuming the fuel checks out as should be....

D

On 17th Nov, 2014 Tom Fenton said:
Sorry to say My Herpes are no better


Ready to feel Ancient ??? This is 26 years old as of 2022 https://youtu.be/YQQokcoOzeY



turbodave16v
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SouthPark, Colorado

Awight,

By the sound of it, you have a fuel pressure gauge connected, such that you can see the fuel pressure gauge whilst driving, and this is as it should be (3-4psi at tickover, rising to around 10psi whan at boost transition point - Zero on the gauge - and rising proportionally with boost thereafter) then you can discount the pump or regulator without question.

I will also assume you have the anti-run-on outlet tube blocked. I personally suspect an ignition problem - despite you changing the dizzy already.

To check, get yourself a nice small 12v bulb of no more than 2w (a gauge illumination bulb is ideal). Connect a simple switch to it, and two long wires, so the bulb can be taped to your dashboard, and the ends of the wire can reach your coil and dizzy.

To start with, connect the wires across the + & - of the coil. At tickover, the lamp will be seen to be flickering quickly, but consistently. As you increase the revs, it flashes much quicker, and from a distance, just appears to get brighter up to around 3500 rpm. From then on, it seems to be permanently on bright.

If the bulb flickers when the engine cuts out or loses power, It IS an ign problem.
If it stays on, maybe dulling as the revs drop, it is NOT related to the ign system, short of the plugs, leads, cap and rotor arm.

You need to isolate this first - assuming the fuel checks out as should be....

D

On 17th Nov, 2014 Tom Fenton said:
Sorry to say My Herpes are no better


Ready to feel Ancient ??? This is 26 years old as of 2022 https://youtu.be/YQQokcoOzeY



iain
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Sold the turbo and seeing what the C20XE can do!

Near Lincoln

Yeah dave i agree but its strange that the car revs fine through the first 3 gears then only really does it by the time you get to 4th. Ill try the bulb thing but ive got a feeling that it will be fine. I tried it before on the old dizzy and it seemed fine.

Ive got the two connections from the dizzy to the coil right but not sure about the other end.

I take it i should have a live ignition feed to the +ve of the coil but what about the negative?

I know there are two wires attached but what are they?


iain
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Sold the turbo and seeing what the C20XE can do!

Near Lincoln

Yeah dave i agree but its strange that the car revs fine through the first 3 gears then only really does it by the time you get to 4th. Ill try the bulb thing but ive got a feeling that it will be fine. I tried it before on the old dizzy and it seemed fine.

Ive got the two connections from the dizzy to the coil right but not sure about the other end.

I take it i should have a live ignition feed to the +ve of the coil but what about the negative?

I know there are two wires attached but what are they?


minimark

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newcastle

how would you describe the fault ??
is it backfiring and popping ???
try changing the fuel pressure regulator , if that is f`ed it will give 3/4 psi at idle but if the diaphram in side is worn u get over or under fueling as soon as u hit any can of boost .

Everyone knows that instructions only have to be read if the thing doesn't work....


minimark

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newcastle

how would you describe the fault ??
is it backfiring and popping ???
try changing the fuel pressure regulator , if that is f`ed it will give 3/4 psi at idle but if the diaphram in side is worn u get over or under fueling as soon as u hit any can of boost .

Everyone knows that instructions only have to be read if the thing doesn't work....


minimark

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newcastle

just fully read dave`s reply and as he says you need to id the fault area

Everyone knows that instructions only have to be read if the thing doesn't work....


minimark

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newcastle

just fully read dave`s reply and as he says you need to id the fault area

Everyone knows that instructions only have to be read if the thing doesn't work....


turbodave16v
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SouthPark, Colorado

Ign modules do break down under load - this is what i used to have happen with mine...

The ign works (as with all cars - as far as i'm aware) by supplying a constant feed to the coil (and ign module) and it simply switches the earth on & off to complete the circuit. This is done through the module unit.

If all seems OK with a bulb on the coil, there is little point looking elsewhere - aside from the leads, plugs, cap and rotor - although they usually work, or don't work....

You still haven't confirmed if you actually WATCH the fuel pressure whilst driving (i stick a gauge under my wiper and feed a pipe through the holes in the back of my bonnet from the fuel line). If All is well here - a carb stripdown is in order. Bear in mind the SU is so simple, they tend to Work, or not work!! *oh well*

I'd be concentrating on cleaning out the float chamber, checking the float is water (fuel) tight and free to pivot, checking the float level jet isn't blocked or sticking, checking the height of the float, check the main jet hasn't got any cr4p stuck inside it, and that is about all that can give the symptons you describe.

If you haven't seen the fuel pressure whilst driving the vehicle, and only when static, then it can be a whole host of other problems...

Call Burlens (01722 412 500) and purchase a turbo carb gasket / seal kit - it'll cost around ?20. The seals in the float chamber and choke spindle are well worth changing whilst it's all apart.

D


On 17th Nov, 2014 Tom Fenton said:
Sorry to say My Herpes are no better


Ready to feel Ancient ??? This is 26 years old as of 2022 https://youtu.be/YQQokcoOzeY



turbodave16v
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10980 Posts
Member #: 17
***16***

SouthPark, Colorado

Ign modules do break down under load - this is what i used to have happen with mine...

The ign works (as with all cars - as far as i'm aware) by supplying a constant feed to the coil (and ign module) and it simply switches the earth on & off to complete the circuit. This is done through the module unit.

If all seems OK with a bulb on the coil, there is little point looking elsewhere - aside from the leads, plugs, cap and rotor - although they usually work, or don't work....

You still haven't confirmed if you actually WATCH the fuel pressure whilst driving (i stick a gauge under my wiper and feed a pipe through the holes in the back of my bonnet from the fuel line). If All is well here - a carb stripdown is in order. Bear in mind the SU is so simple, they tend to Work, or not work!! *oh well*

I'd be concentrating on cleaning out the float chamber, checking the float is water (fuel) tight and free to pivot, checking the float level jet isn't blocked or sticking, checking the height of the float, check the main jet hasn't got any cr4p stuck inside it, and that is about all that can give the symptons you describe.

If you haven't seen the fuel pressure whilst driving the vehicle, and only when static, then it can be a whole host of other problems...

Call Burlens (01722 412 500) and purchase a turbo carb gasket / seal kit - it'll cost around ?20. The seals in the float chamber and choke spindle are well worth changing whilst it's all apart.

D


On 17th Nov, 2014 Tom Fenton said:
Sorry to say My Herpes are no better


Ready to feel Ancient ??? This is 26 years old as of 2022 https://youtu.be/YQQokcoOzeY



iain
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8506 Posts
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Sold the turbo and seeing what the C20XE can do!

Near Lincoln

yep i have the same setup as you dave, the pressure gauge stuck under my wiper so i can watch it as i drive. it goes up perfectly with boost and doesnt faulter even when the car does. Ive just fitted a nice clear inline fuel filter aswell that i can see while driving (advantages of flip fronting and also living in the middle of nowhere hence not needing the bonnet!!!)

Im going to check over all my connections to make sure they are spot on

It does sort of stutter but more cuts in and out than back firing or spluttering.

Just started it up after it was sat all last night and today and it idled perfectly and sat running for 10mins without missing a beat!

Im going with electrical again and go over everything once again!

Found what a nightmare, for something so simple its difficult to find the fault! *angry*


iain
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Sold the turbo and seeing what the C20XE can do!

Near Lincoln

yep i have the same setup as you dave, the pressure gauge stuck under my wiper so i can watch it as i drive. it goes up perfectly with boost and doesnt faulter even when the car does. Ive just fitted a nice clear inline fuel filter aswell that i can see while driving (advantages of flip fronting and also living in the middle of nowhere hence not needing the bonnet!!!)

Im going to check over all my connections to make sure they are spot on

It does sort of stutter but more cuts in and out than back firing or spluttering.

Just started it up after it was sat all last night and today and it idled perfectly and sat running for 10mins without missing a beat!

Im going with electrical again and go over everything once again!

Found what a nightmare, for something so simple its difficult to find the fault! *angry*


SumpNut
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Milton Keynes

I blame fuel problems, i have posted a reply on the met turbo forum, also make sure its not running lean AND check your timing, ive heard of modded turbo engines needing allot of retarted timing - i personally run at over 20 degree BTDC - my high compression turbo engine is a funny one with a funny cam therefore needs funny timing *tongue*


SumpNut
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Milton Keynes

I blame fuel problems, i have posted a reply on the met turbo forum, also make sure its not running lean AND check your timing, ive heard of modded turbo engines needing allot of retarted timing - i personally run at over 20 degree BTDC - my high compression turbo engine is a funny one with a funny cam therefore needs funny timing *tongue*


iain
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Sold the turbo and seeing what the C20XE can do!

Near Lincoln

Im currently running 7-8% as per haynes manual. mixtures fine.

Im checking over all the leccy connections tonight but not sure ill have time to take it for a spin. This is the only way to find out if it still has the problem. *oh well*


iain
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8506 Posts
Member #: 16
Sold the turbo and seeing what the C20XE can do!

Near Lincoln

Im currently running 7-8% as per haynes manual. mixtures fine.

Im checking over all the leccy connections tonight but not sure ill have time to take it for a spin. This is the only way to find out if it still has the problem. *oh well*


turbodave16v
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SouthPark, Colorado

Hi boost Turbo engines do need a lot retard (or more accurately, not as much advance). The rule of thumb is that fore every 1 psi of boost over atmospheric, you retard 1 degree.

As a matter of interest, what boost are you running? If it happens at 14psi, but not at 6psi, then it does kinda suggest fuelling - I hadn't mentioned this as i'd have thought it's the kinda thing you'd have already looked at. Still don't explain whay it'd be ok for 30 secs then pack in... Mixture would generally be weak all the time. *frown*

On 17th Nov, 2014 Tom Fenton said:
Sorry to say My Herpes are no better


Ready to feel Ancient ??? This is 26 years old as of 2022 https://youtu.be/YQQokcoOzeY



turbodave16v
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10980 Posts
Member #: 17
***16***

SouthPark, Colorado

Hi boost Turbo engines do need a lot retard (or more accurately, not as much advance). The rule of thumb is that fore every 1 psi of boost over atmospheric, you retard 1 degree.

As a matter of interest, what boost are you running? If it happens at 14psi, but not at 6psi, then it does kinda suggest fuelling - I hadn't mentioned this as i'd have thought it's the kinda thing you'd have already looked at. Still don't explain whay it'd be ok for 30 secs then pack in... Mixture would generally be weak all the time. *frown*

On 17th Nov, 2014 Tom Fenton said:
Sorry to say My Herpes are no better


Ready to feel Ancient ??? This is 26 years old as of 2022 https://youtu.be/YQQokcoOzeY



Turbo Shed

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Epsom, Surrey

hello all, some of you will know me from miniclassic and lsmoc forums, also my turbo van is in this months rolling road shoot out in Miniworld

I had the same problem. it was the filter in the fuel tank. i cut the tank open, removed the filter and it worked a lot better.

then i changed the needle in the carb as it was too lean and that also improved the power in third and forth gear.

now i'm running a T2 with some help from Turbo Dave

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