Start-up problems after sitting idle

[TheGreenVan]

Hello! I've recently bought a 1982 VW T3 that has some ignition problems. I'm very new to owning a van or car in general, so I'm trying to learn -- very happy for any help or guidance.

My 1982 VW T3 2.0L air-cooled doesn't start after it's not been used for a week or so. It tries and putters but doesn't quite get there. Spraying starter fluid into the air filter solves it, so from what I understand it's a carburetor/fuel pump (?) problem.

My question is how to go about solving it. I could of course just take it around the block once every week, but I'd like to fix the problem and it seems like a good starter project to learn about the engine. The engine is overall in very good shape and the following has been replaced recently (according to the seller, so you could never be completely sure):

• Spark plugs
  
• Ignition harness/wire set
  
• Ignition head and rotor
  
• Air filter
  
• Fuel filter
  
• Hydraulic lifters/tappets
  
• Carburetor cleaning and adjustment
  

Other potentially useful information: The exhaust sputters a decent amount when going downhill in gear (small explosions, basically). After longer drives there is a strong fuel/fumes smell around the engine. There is a small oil leak (but as far as I can tell that's standard in all these vans).

So main questions; how do I go about fixing/replacing this and how?
Very much appreciate any advice for this newbie learning all of this for the first time.

[Rosie n' Jim]

Fuel evaporates from the float chamber over time, the mechanical pump needs a lot of turning over to refill it, especially if the pump rod is worn. Easy fix is fit a quality electric pump. Around ten seconds with ignition on fills the float chamber and the van starts first turn.
Popping from the exhaust on over run or coasting is usually leaks at the head or heat exchanger/silencer flange.
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[aec]

I had this problem, used to disconnect the hose from the pump, insert a small funnel and pour fuel directly in to refill the float chamber before starting of it had been stood up for a while!

In the end I fitted an electric pump, but if it's fitted the safest way with a fuel pump relay it won't run just with the ignition on, it has to be cranking over or running.  Still refills the float chamber much quicker than the mechanical pump ever did (i.e. before the battery runs flat!!)

I've been meaning to add a "prime" push button switch to mine just so that the float chamber can be refilled before trying to start when it's been stood a while.

Some useful wiring diagrams here:
viewtopic.php?t=120838

[joe red]

hello. so i've had this same prob on my 1982 t25 for years. When its been sat a while, turning the key to start doesnt have enough poke to pull fuel thru with the mechanical pump (i've put a new one on, and its not helped). I find i have to have to disconnect the fuel line at the engine, suck the pipe til i get a mouthfull of petrol, reconnect and it starts first time. but obviously i cant keep doing this! So... if i fit an electric pump, in the full line, maybe a foot after the fuel tank, will that fix it? or do i need a VW pump that replaces the mechanical one under the engine?  And/or is there a manual primer product out there? Joe

[aec]

I fitted a Facet Posi-Flow (think it's important not to choose a pump with too high output pressure) a few inches back from the tank outlet, bolted to the chassis rail, with a fuel line straight from there to the carb inlet.  Removed the mechanical pump and fitted a blanking plate over the hole.

The pump could be wired direct to the ignition line but this isn't the safest option, use a tachometric relay so the pump only runs if the engine is running, or one of the other options linked in the above post.

I've yet to add the manual primer, but I'm planning to run a wire from the pump to a push switch on the dash, wired to ignition, so that the line can be primed before cranking the engine.    Even without the "prime" switch, the electric pump pumps far more effectively than the mechanical one at cranking over speeds and it's not long before fuel arrives.

One issue is the noise that the pump makes, its quite a racket.  It ideally needs some sort of acoustic isolation between it and the chassis rail - would be good to hear from anyone who's had success with that.