fuel starvation

Carbs; K-jet; Tanks; Lines; Filler necks, Senders; aftermarket fuel systems; Exhausts and Manifolds;air filters - standard and aftermarket
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mark1gls
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Re: fuel starvation

Post by mark1gls »

Glad you managed to fix the problem and thanks for letting us know what it was as it may help others with the same problem. :-D


Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
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C 20 CCO
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Re: fuel starvation

Post by C 20 CCO »

Aww shucks.... not fixed but nearer the truth.

3 times the car ran out of fuel on the way to the M.O.T garage..... 6 miles grrrrrr.
Although the fuel filter is full of fuel again letting me know the pump is doing it's job; the carb is starved. I really suspect either the float in the carb or the float needle has stuck. The car was stood for around 3 months while I replaced the dash wiring loom, so I expect the float chamber ran dry.

If I pump plenty of carb cleaner down past the butterfly really flooding the chamber will this free the float or float valve; has anyone tried doing this? will the car actually start with carb cleaner rammed down it's throat?

I hope I don't have to strip the carb down otherwise I fear i'll miss the national meet....


kind regards,

Dave.

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

Previously owned: 1984 1.6 CL in alpine white; 1986 1.6 GT in met light blue over black body kit; 1990 1.8 GT2 in silver.
Currently: 1991 GT2 in Pearl green metallic.
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C 20 CCO
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Re: fuel starvation

Post by C 20 CCO »

Just noticed on my spare carb the fuel chamber isn't below the butterfly as I thought. It looks like its rear left as you look from over the rad.

If I take off the co adjusting screw tube that sits over the idle fuel/air jet; would pumping carb cleaner through the jet end up in the fuel chamber? I'm thinking the cleaner would rest on anything and possibly act as release agent. If the fuel chamber is below maybe I could also add fuel to help free whatever is stuck.....

What do you think....?


kind regards,

Dave.

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

Previously owned: 1984 1.6 CL in alpine white; 1986 1.6 GT in met light blue over black body kit; 1990 1.8 GT2 in silver.
Currently: 1991 GT2 in Pearl green metallic.
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C 20 CCO
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Location: Burnley, Lancashire.

Re: fuel starvation

Post by C 20 CCO »

The story continues.... The Garage owner, peter Lord of vale st garage, Bacup told me how to take off the top of the carb. I had my own tools but he offered me his. So i set to and clamped and removed the 2 water pipes, the 3 electrical connectors. 2 on the rear left and one at the front, the 3 screws holding the auto choke, Removed the 4 screws holding the top half of the carb and the 3 bolts through to the flange. Removed the fuel supply pipe and finally a vacuum hose top rear. The top came off pretty easy, there was fuel in the float bowl surprisingly.
I couldn't see any sticking of the valve but removed the pin holding the float, thus releasing the valve. I carb cleaned all the jets and pipes literally everywhere. Used an airline to purge cleaner out of the head, mopped fuel from the float bowl and used the airline here to. The needle valve looked in great condition to say it's done 139K.

So after putting everything back I fired her up and everything looked good up until it died....WTF....

Pete seems to dislike the new fuel vapour reservoir. He clamped the fuel return and we set the revs to 2500 for a minute or so. We're both in agreement the idea to permanently use anything to restrict the flow back to the tank, well it could flood the carb and cause a fire with fuel spillage. The engine ran well until we unclamped the return pipe, after a minute she died.

I still have the original fuel vapour reservoir and pump. I'm going to drop them at the garage this Friday afternoon; with a view to refit the original fuel vapour reservoir. We're both in agreement there seems to be fuel right up to carb.... Then what?

To be continued folks!


kind regards,

Dave.

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

Previously owned: 1984 1.6 CL in alpine white; 1986 1.6 GT in met light blue over black body kit; 1990 1.8 GT2 in silver.
Currently: 1991 GT2 in Pearl green metallic.
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essextom
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Re: fuel starvation

Post by essextom »

stick a weber on it.


mark1gls
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Re: fuel starvation

Post by mark1gls »

Sorry can’t be much help with the carb as I know nothing about the 2e2 as I went with essextom suggestion and fitted a Webber Carb to my car when the original carb started to play up.... Fixed all the running problems I had.


Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
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tulyar
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Re: fuel starvation

Post by tulyar »

Did you remove the jets from the carb before cleaning them? Old petrol can harden like varnish/resin and spray isn't always adequate to dislodge it.

If you didn't remove the jets use a really good fit screw driver and check the tip of the jet - its an ideal place for a blob of resin to form.

I have found overnight soakings in carb cleaner and probing with a soft wooden pick will dislodge the resin.


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C 20 CCO
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Re: fuel starvation

Post by C 20 CCO »

cheers for that info, though i did blast through almost a can of cleaner, if the problem persists then i will look at the jets again.
Mum in law dropped off the original fuel pump and vapour reservoir at the garage yesterday, so I'm hoping pete can refit the res to see if there is an improvement.
I can't get to the garage until next Thursday anyway, so fingers x'd it will be fixed by then.... these characters eat sleep vw's ;-)


kind regards,

Dave.

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

Previously owned: 1984 1.6 CL in alpine white; 1986 1.6 GT in met light blue over black body kit; 1990 1.8 GT2 in silver.
Currently: 1991 GT2 in Pearl green metallic.
User avatar
C 20 CCO
Posts: 258
Joined: Sat Jan 06, 2018 7:38 pm
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Location: Burnley, Lancashire.

Re: fuel starvation

Post by C 20 CCO »

I split the carb, again to remove the jets but couldn't get them to budge. Had to be careful as they are brass and damage comes easy. So I dropped the head in a ultrasonic cleaner for an hour or so. I used Aldi lemon multi surface cleaner, my (old school style) neighbour swears by it having cleaned his carbs on bikes and engineering stuff over many years with great results.
After washing and drying i replaced the float valve anyway. Rebuilt the carb, replaced the section of fuel return pipe with the restriction. If i removed this and the carb starving ceases to be..... But no... After firing her up she died within a few minutes.
When running with the air filter housing removed there is a definite sucking sound from the carb. So there must be a good healthy down draught provided by the vacuum.... Is that right? Is that what that noise is?

I changed the vapour separator as a precaution because i suspected that not enough fuel was being diverted to the carb. After buying a new one from vw heritage i wasn't impressed with the fit as i had to butcher the air filter bracket. It looked cheap quality too... I'm still uneasy about this part especially as I've replaced so much of the fuel system; something doesn't sit right. I've decided to buy a meyle unit hoping for better quality.

Later today I'll check for 12v supply on the two connector plugs.... You never know!

If the carb flange had split would that have any effect on the vacuum hoses on the carb? What I'm getting at is if the down draught is weak will the vacuum hoses have a weak pressure too. At the moment the vacuum pipes appear to have good pressure.

I could do with some professional help from anyone who worked for vw, boy..how i could do with that. I'm surprised no professionals get involved with the chat forums.


kind regards,

Dave.

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

Previously owned: 1984 1.6 CL in alpine white; 1986 1.6 GT in met light blue over black body kit; 1990 1.8 GT2 in silver.
Currently: 1991 GT2 in Pearl green metallic.
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C 20 CCO
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Re: fuel starvation

Post by C 20 CCO »

Going to try the 0.8mm welding tip trick, just about run out of patience after 3& a half months chasing ghosts.

I’m even suspecting the new spacer in between the pump & engine block. I’ve ordered a fuel pump pressure test kit to check what pressure comes from the pump. Does anyone have an original vw spacer to advise the thickness. I have a vernier gauge to check mine, any help will be gratefully received.


kind regards,

Dave.

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

Previously owned: 1984 1.6 CL in alpine white; 1986 1.6 GT in met light blue over black body kit; 1990 1.8 GT2 in silver.
Currently: 1991 GT2 in Pearl green metallic.
Mark H
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Re: fuel starvation

Post by Mark H »

Dave

Got a spare filler neck if you want to try it ? Located M61 junction 6

Mark


Mark

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C 20 CCO
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Re: fuel starvation

Post by C 20 CCO »

Eventually got it running and it seems to be ok. Hit the hills at speed and didn’t falter, so looked for m-way with Hill’s. Got her up to 75 maybe a tad more; didn’t miss a beat.

I removed the fuel pipe holding the welding tip and replaced with none restricted pipe.Restriction to fuel back to the tank wasn’t the answer, so I thought.,
The brand new heritage pump proved faulty and until finding that fault seemed to confuse things. After replacing that pump air was still getting into the in-line filter, so I replaced the flexible fuel hoses between tank and filter . Small amount of air still in filter but 95% fuel and the pressure seems strong. I suspected the hose from the tank was the culprit, but will pressure test it to be sure. Nothing wrong with the pierburg carb after all, still at least it’s been cleaned and sits on a new flange.

Going to drive up to weatherby on Saturday via M62 plenty of steep gradients for a test drive. If that trip proves successful, i’m Back in business.

Still gutted I missed the big meet this year 😒


kind regards,

Dave.

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

Previously owned: 1984 1.6 CL in alpine white; 1986 1.6 GT in met light blue over black body kit; 1990 1.8 GT2 in silver.
Currently: 1991 GT2 in Pearl green metallic.
mark1gls
Posts: 3954
Joined: Thu Apr 02, 2009 9:28 pm
fill in the right answer: 10
Location: Somerset

Re: fuel starvation

Post by mark1gls »

Keeping my fingers crossed for you......


Mk1 78 Scirocco GLS 1.6 FR, weekend toy.
Mk1 88 Golf GTi cabriolet 1.8 DX. Daily drive.
Membership No. 323
Mark H
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Re: fuel starvation

Post by Mark H »

Superb news Dave. Keep the faith mate.

Lets plan a North West Mini Meet, once your happy with the running..

Good Luck with the Weatherby run, let us know how you fair.


Mark

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Membership Number 1296
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C 20 CCO
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Re: fuel starvation

Post by C 20 CCO »

Met some of the members last weekend at the barn, nice to meet you eventually. My Rocco still not quite there yet. Fluid is settling on the exhaust manifold and inlet manifold and idle is rough. I guess the rubber ‘o’ ring in the inlet manifold may have perished. Carb now off, support bracket under the inlet came off without a hitch. Bolts soaked in plusgas, ordered new hex key and pray the bolts don’t round off.
Hopefully when new gasket and o ring are replaced normality and my sanity will return.
Fingers crossed.


kind regards,

Dave.

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

Previously owned: 1984 1.6 CL in alpine white; 1986 1.6 GT in met light blue over black body kit; 1990 1.8 GT2 in silver.
Currently: 1991 GT2 in Pearl green metallic.
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