Club 80-90 Forums

can anyone help?
around town my van pulls great up hills and on the straight but when on the motorway climbing up hill in 4th gear doing around 50-60mph its starts to loose power as if it is missing!
If i pull back on the throttle it regains power and when i start to go down hill or straight there is no problem! could this be carb problem?

location may help.
add to you profile as if your in gloucester i can pop round.

i am in warrington cheshire

davenwdc wrote:can anyone help?
around town my van pulls great up hills and on the straight but when on the motorway climbing up hill in 4th gear doing around 50-60mph its starts to loose power as if it is missing!
If i pull back on the throttle it regains power and when i start to go down hill or straight there is no problem! could this be carb problem?

sounds about right to me.
how long have you had the van?

This does sound like fuel starvation. Often it only really shows itself when maxing out. Mine does it (again) at these kind of speeds/power bands and suspect its crap in fuel line somewhere (again). Last time i replaced fuel filter on line and cleaned filter inside fuel inlet on carb and it behaved itself for weeks but its back once more - no doubt long term cure will need tank swooshing out (or fitting a new one) and blowing everything clear including carb jets.

Came back from Kenilworth last night and soon as I hit sixty it loses power until I drop to 40 then it'll climb (slowly) once more, repeating the cycle. Thats deffo fuel statvation. The carb float chamber runs too low, recovers for a bit after the speed drop then does it all over again. Was fine on the way there but awful on the way back so expect theres muck in the fuel line again somewhere. Even the tank outlet pipes can get semi-obstructed by rust - or even water in the fuel will do it.

One thing I have noticed is that the fuel line seems to switch from hose to narrow plastic pipe in places so might pay me to replace with longer lengths of pipe with fewer joins to ensure full delivery of fuel. That seemed to work well on bugs I've owned.

hi Kev

I have had the van about 2 months and i went away the first weekend after i bought it and when on the A55 to wales noticed the missing but only happened once or twice.
I give the van a run on a Sunday cos its parked up all week and the problem seems to have getting worse. I was told it could be water getting into the fuel some how! Also seems that the revs are high and the only way to lower them is to jab the throttle pedal. Oh by the way my vans a 1990 DG engine.

the previous owner replaced the fuel tank about three years ago. whats the best way of seeing if water is in the fuel? draining the tank or would it collect in the filter?

davenwdc wrote:hi Kev

I have had the van about 2 months and i went away the first weekend after i bought it and when on the A55 to wales noticed the missing but only happened once or twice.
I give the van a run on a Sunday cos its parked up all week and the problem seems to have getting worse. I was told it could be water getting into the fuel some how! Also seems that the revs are high and the only way to lower them is to jab the throttle pedal. Oh by the way my vans a 1990 DG engine.

been getting worse in this wet weather?
easy check is the fuel filter, if it has water in it you'll know.
disconnect it and let the contents fall to the floor.. water will form droplets and fuel will spread into the floor.
or disconnect the fuel pump (fuel out let) and point it into a jar, it should squirt powerful jets of fuel when the engine speed is raised..any water will pool at the bottom of the jar

revs will be high when the engine is cold, it's the auto choke/idle speed doing it's job.. there are three stages to that too

if there is water getting in I'll bet it's the perished breather hoses on the tank, or the filler neck
water in the tank can mostly be removed by filling the tank to a qurter full and disconnecting the outlet pipe.. letting the fuel fall into a jar..again water will sink to the bottom