fuel starvation

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C 20 CCO
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fuel starvation

Post by C 20 CCO » Sun May 20, 2018 9:15 pm

Getting my car ready for the road and it suddenly died, fuel starvation. I've had it happen years ago and it turned out to be the pump. I've checked inside the tank and it's very clean, I've now replaced all the fuel delivery pipes, the pump, inline filter and fuel vapour reservoir. I ran the engine at 3,400 revs for 4-5 minutes without a problem.
Is the inline paper filter supposed to be almost empty whilst the engine is running?

I did scan threads but couldn't find anything with a fix especially as I've changed virtually everything to do with fuel delivery.

I've had scirocco's for years and, you know I can't remember if the filter is to hold more fuel when running. I thought it should, just a feeling..... The filter does fill after a short period of time after the engine has stopped. Don't suppose anyone can check theirs when you're out next time. I'm even thinking it could be an airlock, if I hold the filter in a vertical position fuel is still pulled through at a slow rate. I've pinched pipes with my fingers to stop fuel flow, no difference to the filter fuel volume.......


kind regards,

Dave.

To be old and wise......
You must first be young and stupid!

In the garage : 2005 Volvo V50 2L D in brilliant blue metallic.
2011 Mazda2 Tamura in vibrant ebony metallic.
Prized possession- 1991 GT11 in Pearl green metallic.

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james butler
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Re: fuel starvation

Post by james butler » Sun May 20, 2018 11:12 pm

you should see some fuel in the filter and should gush when being cranked.
either your pump is dead or you have serious vapour lock or blockage somewhere


I dont mind project cars but I HATE SANDING!!!

mark1gls
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Re: fuel starvation

Post by mark1gls » Mon May 21, 2018 9:14 am

What Carb do you have?


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C 20 CCO
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Re: fuel starvation

Post by C 20 CCO » Mon May 21, 2018 2:52 pm

I have a 2e2 carb, the car has been sorn since last May and the engine has been turned over periodically to try and keep things going.
I forgot to mention; when I disconnected the fuel pipe coming up to the filter from the tank, I blew down the pipe. I could hear bubbles forming in the tank so I guess there is no blockage there. Since I've changed just about every other bit of pipework I doubt there is a blockage there either.

The pump is a meyle pump from VW Heritage bought two weeks ago. It seems all the parts I have changed haven't made a difference. So I'm having difficulty in understanding what else the problem could be.... When I last had this problem I used a pump from my previous rocco. This had been re-boxed after use and sat on a shelf for 12 months. It turned out this pump was goosed too due to fuel being left behind in the pump, so rubber bits perished. When I bought a new pump that cured things, so now I'm questioning the new pump. I suppose I could attach a longer fuel hose to the pump and drop it into a fuel can then crank the engine to see how much fuel is being drawn through????

Cheers for your replies, much appreciated.... need it fixed so I can make the national meet :-o


kind regards,

Dave.

To be old and wise......
You must first be young and stupid!

In the garage : 2005 Volvo V50 2L D in brilliant blue metallic.
2011 Mazda2 Tamura in vibrant ebony metallic.
Prized possession- 1991 GT11 in Pearl green metallic.

mark1gls
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Re: fuel starvation

Post by mark1gls » Mon May 21, 2018 7:12 pm

Next thing on the list must be the carb..... not really up on 2e2 carbs, is there a float chamber on the carb that needs setting up/adjusting?
To much fuel getting back to the fuel tank (I think this is more a Webber carb problem..)


Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
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C 20 CCO
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Re: fuel starvation

Post by C 20 CCO » Tue May 22, 2018 10:07 am

I'd have to study the carb in a bit more detail, never really had much involvement as it just runs and runs.

I'll have a better idea of how it's running when I drive it to the M O T station, up and over the moorland "B" roads. I'm hoping it's something just sticking and needs a gentle prod to get it back in shape.....


kind regards,

Dave.

To be old and wise......
You must first be young and stupid!

In the garage : 2005 Volvo V50 2L D in brilliant blue metallic.
2011 Mazda2 Tamura in vibrant ebony metallic.
Prized possession- 1991 GT11 in Pearl green metallic.

mark1gls
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Re: fuel starvation

Post by mark1gls » Tue May 22, 2018 12:28 pm

Fingers crossed, at least at the MOT you should get a CO reading so you can check the mixture if it's running to lean, about 2% CO is where you want to be..


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C 20 CCO
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Re: fuel starvation

Post by C 20 CCO » Wed May 23, 2018 7:31 am

Do you think even if there was a a problem within the float chamber there should be more fuel sitting in the filter? You know how sometimes you get a nagging doubt...... And something doesn't feel right.
I'd taken the original pump apart to let it air dry when I removed it, I couldn't find a fault. I'm tempted to refit it and see if there is an improvement.


kind regards,

Dave.

To be old and wise......
You must first be young and stupid!

In the garage : 2005 Volvo V50 2L D in brilliant blue metallic.
2011 Mazda2 Tamura in vibrant ebony metallic.
Prized possession- 1991 GT11 in Pearl green metallic.

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james butler
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Re: fuel starvation

Post by james butler » Sun May 27, 2018 5:59 pm

if you can't see fuel coming through the filter then somethings definitely wrong.
i would certainly connect the out put of the pump to a long pipe and put it into a jar and see if it pumps then.
out of curiosity where is your fuel filter? before or after the pump?


I dont mind project cars but I HATE SANDING!!!

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C 20 CCO
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Re: fuel starvation

Post by C 20 CCO » Mon May 28, 2018 9:32 pm

Hi James,
Fuel filter is before the pump, tomorrow i will attach a pipe as you suggest. Then maybe as I suspect this new pump is faulty. Today I pulled the original pump apart and found no faults; I pumped it manually with my thumb over the inlet. There was suction and seemed pretty strong, what's the betting that this little sucker works when I reattach it.

I also bought the plastic spacer that fits in-between the pump and engine block from a supplier in Germany. The new Meyle pump doesn't have an "o" ring or have the design for one; I thought this was strange as every other pump had an "o" ring. I also thought the mating of both parts didn't look quite right. Could be me just looking for excuses. Lets see what the pump does tomorrow.


kind regards,

Dave.

To be old and wise......
You must first be young and stupid!

In the garage : 2005 Volvo V50 2L D in brilliant blue metallic.
2011 Mazda2 Tamura in vibrant ebony metallic.
Prized possession- 1991 GT11 in Pearl green metallic.

User avatar
C 20 CCO
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Joined: Sat Jan 06, 2018 8:38 pm
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Location: Burnley, Lancashire.

Re: fuel starvation

Post by C 20 CCO » Tue May 29, 2018 9:44 pm

Might be a trip to a garage with someone who has knowledge on fuel delivery. Hope I get this sorted as it's threatening my national meet trip.
Fuel is pumping right up to the carb in good quantities, so nothing wrong with pump or vapour reservoir. If I look into the carb I see fuel being sprayed into the chamber when I operate the accelerator lever. Is there supposed to be fuel sat on the lower butterflies to keep the carb fed? Only asking because after a few minutes of idling the carb runs out of fuel. So I think I can say it looks like the problem is with the carb. I have a second carb which needs to be tested, are they easy to fit? My carb has never been off the engine so I don't know what state the flange is in. Oh lordy......

I don't want to change to a Webber as I like the 2E2 carb but has anyone had these symptoms before?


kind regards,

Dave.

To be old and wise......
You must first be young and stupid!

In the garage : 2005 Volvo V50 2L D in brilliant blue metallic.
2011 Mazda2 Tamura in vibrant ebony metallic.
Prized possession- 1991 GT11 in Pearl green metallic.

User avatar
C 20 CCO
Posts: 171
Joined: Sat Jan 06, 2018 8:38 pm
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Location: Burnley, Lancashire.

Re: fuel starvation

Post by C 20 CCO » Tue May 29, 2018 10:25 pm

Just had a thought... Could the floats in the carb chamber be stuck due to fuel evaporation. I'm strapped for time as I'll be away from home for a week; so may have to look into this on my return.


kind regards,

Dave.

To be old and wise......
You must first be young and stupid!

In the garage : 2005 Volvo V50 2L D in brilliant blue metallic.
2011 Mazda2 Tamura in vibrant ebony metallic.
Prized possession- 1991 GT11 in Pearl green metallic.

User avatar
C 20 CCO
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Joined: Sat Jan 06, 2018 8:38 pm
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Re: fuel starvation

Post by C 20 CCO » Sat Jun 09, 2018 9:27 pm

Back off my hols and back to head scratching. I'm going to swap out the vacuum pipes one by one. The carb flange has never been swapped out so looking to do this. VW Heritage has one for £12.95, has anyone bought one, is it from the original manufacturer?
Does anyone know if vw dealers still have them in stock?
I will be getting in touch with the dealer sometime next week if I get no replies before then. Cheers 🍻


kind regards,

Dave.

To be old and wise......
You must first be young and stupid!

In the garage : 2005 Volvo V50 2L D in brilliant blue metallic.
2011 Mazda2 Tamura in vibrant ebony metallic.
Prized possession- 1991 GT11 in Pearl green metallic.

User avatar
C 20 CCO
Posts: 171
Joined: Sat Jan 06, 2018 8:38 pm
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Location: Burnley, Lancashire.

Re: fuel starvation

Post by C 20 CCO » Tue Jun 12, 2018 8:26 pm

Fixed......
Bought some carb cleaner and fired up the engine; sprayed it all around the carb and....... Nothing! So no vacuum leak anywhere, don't need a carb flange at least. Renewed all the vacuum hoses anyway.

If fuel pump is working ok but the new in-line filter is almost empty, could the new in-line filter be faulty. Yep! Brand new Mann filter wasn't allowing enough fuel to pass through. Tried another filter, make unknown and voilà.
M.o.t time and change rear beam bushes and national meet here we come!

I did read about adding a welding tip to stem the fuel flow back to the tank, but that's not a modification in the design. It just had to be a simple fault in the end.


kind regards,

Dave.

To be old and wise......
You must first be young and stupid!

In the garage : 2005 Volvo V50 2L D in brilliant blue metallic.
2011 Mazda2 Tamura in vibrant ebony metallic.
Prized possession- 1991 GT11 in Pearl green metallic.

Mark H
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Re: fuel starvation

Post by Mark H » Wed Jun 13, 2018 7:39 am

Great news, get in the NW convoy down to Telford.. Look out for announcement from Heath..


Mark

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