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runs for 10 minutes then won't start for 1/2 hour
glint - April 1st, 2006 at 06:47 PM

Hi
got a problem with my '69 beetle. she's a 1500 fairly standard bug as far as i can tell. had it for 3 years.
history: i smell fuel and pull over. the hose from the fuel pump is split and has been squirting fuel all over the place. luckily i had a piece of old tubing - replaced and on my way.
later that week, engine starts to backfire and fade then stop [middle of traffic victroria road OF COURSE] wont restart. after 1/2 hour or so starts again and i limp home. Get new fuel tubing and filter. hope for the best.
Lets me down again about 10 minutes into a drive to smithfield..remove carby top plate by the roadside and check fuel shutoff valve, big piece of cottony crud - obviously from failed fuel tube Ah-HAH! put it all back together and on my merry way [back home of course...don't trust her now]
all is fine for a week [to and fro work- about 5 mins. drive]
then had to go to avalon, about 10 mins. into drive bang-bang fade-fade etc. bastard stops again.same story - limp home. so,get new coil [seen thisone before -coil gets hot and fails..] run engine for 1/2 hour at high idle in backyard- all seems good so, test run, about 10 minutes into test -the rotten sl*t does it again.
Alright then, new points,condenser, carby kit. Do the buisness and test seems ok [backyard 3/4 hour various revs - neighbours real agro] road test.
we'll i'll be jiggered if it doesn't fail again - fade in power the odd backfire then stop!
I'm stumped got one slightly noisy tappet [#3] other than that from cold it runs nice...up until it gets warm. any ideas?
cheers


REDKG - April 1st, 2006 at 07:01 PM

sounds like a fuel problem. either a partial blockage or dirty fuel ie: water. did you clean the fuel pump also flush the tank and fuel line. l


koolkarmakombi - April 1st, 2006 at 07:03 PM

do a cold and hot compression test.

Pull the plugs hot and see what they look like.

Double check the valve adjustments.

when it wont start, check fuel, spark, engine bay wiring etc.

ahything modded in the engine bay? like ANYTHIG, a rewire through an ungrommeted metal connection???????

CAN be something w-e-i-r-d that often is obvious in hindsight.

kkk


glint - April 2nd, 2006 at 09:40 AM

Thanks for your replies.
plugs were replaced and so were leads. a quick look at #4 plug yesterday showed it to be good [not wet].
engine bay wiring all good. when it wont start i have a good spark,fuel filter 3/4 full.
put another solex30-2 on yesterday [one with an ECV]. runs smooth...until it gets hot.then same problem.

will look at valves today...
cheers


koolkarmakombi - April 3rd, 2006 at 01:38 PM

progress?


Volkswagenboy - April 5th, 2006 at 08:40 PM

Could it be a vapour lock problem?
-Staggers.


aussiebaja - June 13th, 2006 at 07:23 PM

hi sounds too me like its your coil getting hot then breaking down ,once it cools it starts and runs again until it gets hot then breaks down again


MickH - June 13th, 2006 at 08:11 PM

Fuel tank blockage?? If you've already replaced the coil as per stacy b,try and blow fuel back to the tank after engine has stopped (with fuel cap off).If there is a lot of pressure/effort to blow back it might be blocking.


beerdoc - June 13th, 2006 at 09:31 PM

Look for fuel filter where you think there would not be one

Sorry thats my humor or attempted of

What I mean is check all fuel lines for filter ie under tank,next to gearbox and replace

I have same problem with 75L

Did what Mick H suggested and if it happens again will have to remove tank I think


Iwish4aSynchro - September 10th, 2006 at 10:49 PM

Dont know if this helps and may be totally unrelated but, I had this zxr250a jap road racer and it would do the same thing; meaninig the symptons are exactly the same yes different vehicles and all that but they both have fuel and spark, right. After many a dollar spent on sourcing the prob it turned out to be tht jets in the carbs. Jets were too small by a nats hair. Replaced jets on all four carbs and never had the prob again. If it helps great if already done sorry for lateness.


greedy53 - May 29th, 2008 at 08:19 PM

i had this problem a few years ago very similar for me it was a coil breaking down when hot stop wait until it cooled and away again
hope that helps


squizy - May 29th, 2008 at 08:45 PM

Quote:
Originally posted by Volkswagenboy
Could it be a vapour lock problem?
-Staggers.


I reckon this too. Check where your fuel line is running and see if it's sitting across your risers or manifold, and move it away if it is. It could be reaching a certain temperature, and then causing a vapour lock.


Adsman - May 29th, 2008 at 08:47 PM

A few thoughts.
Check the fuel filter in the bottom of the tank as it could be blocked.

As a suggestion put a long piece of hose between the fuel pump outlet and the carby. Once hot and failing pull hose off carby and direct to a bucket crank engine and check flow.

The problem sounds like an electrical issue or flooding...just check the fuel stop solenoid also in case the wire is loose causing HR to develop. As mentioned check the plugs once it fails...all of them. Just a question when it fails doing it suddenly die or slowly fade out? More details on the failing and immediate events before.


68AutoBug - May 29th, 2008 at 10:33 PM

I had a similar problem years ago
actually many times [not VW]
but the condenser used to fail..
once it cooled down it would go again until hot..

once i found this I used to have a spare condenser mounted ready to go...

and this happened lots of tiimes..

I had a loose connection to My coil a while back..

ended up throwing a good coil away... lol

Maybe the fuel cutoff is faulty...

I always throw the fuel tank filter away...

and place a filter under the tank...

Do You have the fuel filter in the engine bay???
NOT a good place...

LEE


esevwbits - October 7th, 2009 at 10:45 AM

id go with the coil. when they get hot, no spark! try a spare one!


aintgotitmusthaveit - October 7th, 2009 at 11:19 PM

Had this too. Mine turned out to be crap in the fuel line. It go sucked into A non STD elbow in the fuel line. When it got compacted (after driving a while) I would splutter to a stop. As the fuel ran out I was getting lean bAckfires. When the carb stopped sucking the gunk relaxed allowing fuel to partially flow again. I could restart eventuLly but it ran like a dog. Found this by checking a fuel line just after it stopped. It Nd the fuel filter before the carb were empty. Hope this helps