Van dying while at speed

[butthefuko]

Dear All

I have a very annoying problem and goes something like this,

The van starts perfectly it drives without any issues.....................until such time i start to loose power it is as though the van is starved of fuel.

What I have witnessed is the issue only manifests itself when the engine has warmed up and Iam at a steady 50mph I then start to loose power the engine spluttters/chugs along and eventually dies. I pull over wait a couple of minutes fire the engine back up and it seems to be fine pulling away then the issue returns once at a steady 50mph?


Any advice would be greatly appriciated

EarlyBay 1969 1600cc LHD campmobile

Thanks

Butthefuko

 

[BJ1]

Fuel starvation - the pump isn't delivering enough to keep the carb full. Could be the fuel filter in the tank, and/or an additional filter in the supply line and/or the pump has a split diaphagm and/or the pump push rod is very worn giving short travel. In other words you need to check that the pump is supplying enough fuel.
Easy way to do that. Disconnect the pump outlet pipe at the carb end and put it into a jar in the engine bay. Take out the rotor arm (we don't want a fire!) and get someone to turn the engine over on the key. You should have a good flow out of the pipe into the jar. My guess is that you will find just a dribble coming out. Then you'll need to go through the fuel line starting at the tank end by draining the tank and removing the filter inside. Lovely job best done upside down in the rain with fuel dripping down your arm :lol:

 

[butthefuko]

Fuel starvation - the pump isn't delivering enough to keep the carb full. Could be the fuel filter in the tank, and/or an additional filter in the supply line and/or the pump has a split diaphagm and/or the pump push rod is very worn giving short travel. In other words you need to check that the pump is supplying enough fuel.
Easy way to do that. Disconnect the pump outlet pipe at the carb end and put it into a jar in the engine bay. Take out the rotor arm (we don't want a fire!) and get someone to turn the engine over on the key. You should have a good flow out of the pipe into the jar. My guess is that you will find just a dribble coming out. Then you'll need to go through the fuel line starting at the tank end by draining the tank and removing the filter inside. Lovely job best done upside down in the rain with fuel dripping down your arm :lol:

BJ1

Many Thanks

Will investigate and report back

Cheers

Butthefuko

 

[Guest]

if your running lean pull one of your spark plugs and see what colour it is.

running too rich the plug will be dark and sooty, running lean it will be a white colour, it ideally should be a nice colour of grey/brown.

 

[Trikky2]

If the above advice doesent find the problem then another thing to check is the fuel tank breather. If its blocked a vac will build up and reduce the flow from the pump.

Its easy to detect. Drive until the problem occurs then stop and take off the fuel filler cap. If theres a vac you will feel and hear the air bieng sucked in as the cap comes off.

 

[uber cool]

also there are 2 types of pump requiring different length push rods. You may have the shorter pushrod where you need the longer push rod and hence not delivering enough fuel.

Look at fuel pump parts on the VW hertiage website, its states the pushrod length required for which pump.

From memory I think if the heel of the pump sticsk out below the flange you need the 100mm pushrod and if the hell is flush with the flange you need the 108mm rod.

 

[ProfessorWheeto]

My beetle did this, float bowl was always full so that ruled out fuel pump, turned out to be a lump of **** stuck in the main jet. So if your float bowl is full proving the pump works, I'd whip the carb off, give it a light strip down and clear the jets out with carb/disc brake cleaner (the stuff in the spray cans is perfect, with the hook shaped main jet remember to blow it both directions (if that makes sense!)

 

[butthefuko]

Guys

Problems still exists even after doing the following works


I have replaced the fuel pump + pushrod
I have replaced leads and plugs
I have replaced fuel hoses and had the tank cleaned out.
I have replaced the ignition switch

Took the van out for about a 3miles at 60mph and still doing the same I am stuck as to what else to look for?


Cheers

 

[ProfessorWheeto]

Strip and clean your carb like I suggested?

 

[butthefuko]

Strip and clean your carb like I suggested?

ProfessorWheeto

I will have butchers tomorrow and report back.


Cheers

 

[ozziedog]

At the moment, my money is on the fuel breather, try a short run with not too much fuel with the fuel cap off with some cling film and elaccy band over the fuel inlet pipe instead of the fuel cap, pop a fuel holes in it, its just to stop crap getting in the tank and too much sloshing.. Or if you are brave, just no fuel cap, a tiny bit dangermouse, but would prove / eliminate breather .

Ozziedog,,,,,,,,, Stellafied :shock:

 

[lard]

Strip and clean your carb like I suggested?

ProfessorWheeto

I will have butchers tomorrow and report back.


Cheers

Where abouts are you located? My spare carb is available if you are local to Cambridge and want to run a quick test to rule it in/out

 

[butthefuko]

Strip and clean your carb like I suggested?

ProfessorWheeto

I will have butchers tomorrow and report back.


Cheers

Where abouts are you located? My spare carb is available if you are local to Cambridge and want to run a quick test to rule it in/out

I'm based in reading I been meaing to get hold of carb as backup.

 

[sam@bugeyeddesigns]

My beetle did this, float bowl was always full so that ruled out fuel pump, turned out to be a lump of **** stuck in the main jet. So if your float bowl is full proving the pump works, I'd whip the carb off, give it a light strip down and clear the jets out with carb/disc brake cleaner (the stuff in the spray cans is perfect, with the hook shaped main jet remember to blow it both directions (if that makes sense!)

I had the same symptoms as the op says with my bug and found a lump of rubber stuck in one of the jets.

 

[Jimbly]

For what it's worth, I had exactly this on an old V8 ex-Police riot van. Turned out to be a clogged fuel filter which would flow fuel for light throttle/load and for a short while as the load/speed increased, then starve the engine, till it slowed down or stopped for a bit and the filter could fill again and resume flow.