Novice needs help!

[EpsomAir]

I apologise in advance if this is a stupid question but I took my van for a spin this afternoon and noticed a problem. It started up ok eventually, but once going would stuggle for power when accelerating and the revs dropped right down but would rev fine when the clutch was depressed. So I had a butchers and noticed a hole in the carb and for the life of me cannot remember if this was there before or not. So I had a look at the photo of the engine from the advert when I bought it and there seems to be a bit missing now. Two pics included of a before and after. Has a bit dropped off or stolen or has that got bugger all to do with this problem and could have been taken off by seller for a genuine reason. Any help much appreciated.

 

[rob]

there should be a blanking plug fitted ........... have a look in the tinware and see if you can see it and loctite it back in , i,m not sure if these are available to buy on there own ?

 

[dave]

you do not say what year, where your bus is from or any carb details. just look in haynes and bently manuals and can not see anything, also just looked at my 69 bay and mine has nothing there either BUT the larger hole on mine is filled, ie there is a casting there from the factory. sorry i am not of much help but may be with further details someone can help, i ll be interested as it has got me thinking.
good luck in getting it sorted!

 

[Araon]

the top pic shows a throttle valve positioner, where your gonna get a new bung from?? you could try to make a lead plug.....

 

[Hilly_70]

.. i wouldn't drive it or even start it without that plug in to be honest .. cos its gonna push fuel all over i would have thought .. I'd look carefully for the bung .. if not you could try and bung it with something else but i would be looking for a new carb mate ..

Hilly

 

[Bookwus]

Hiya epsom,

In your second picture you are missing (what we call over in the States) the blow-out plug. This plug is designed to blow out in the event of a backfire. Had you experienced any "rough running" or backfiring prior to that sudden decline in performance?

I have heard of people over here who have replaced that blow out plug with a dime. Whatever you do, make sure that you get the hole sealed up. And when you do that you can seal it with an epoxy but also make sure that you peen it in place.

 

[EpsomAir]

Prior to noticing this bit missing it was running fine with no back firing so hopefully it just fell out. It's probably too much to hope for that i will find the bit in the engine bay so will have to find a way to plug it. The coin fix sounds like it could be within my limited skills.
Thanks for your help everyone I may have to wait to the weekend to sort this out when I have a bit more daylight to try and find that bung bit.

 

[richbaker78]

in my experience this is a problem on cheaper repro carbs (bocar) as mentioned above 5p coins and some araldite will be an adequate fix. but to be 100% the answer is a replacement carb or to rob another good carb of its plug (which seems a bit pointless really!)

 

[SteveGTU]

Hey Fella, I had the exact same thing happen on my bus and found the bung in the engine bay, stuck it back in and gave it a wack, runs like a dream now, guess you just need to find the bung

 

[BJ1]

If you look carefully around the rim of the hole you will see 3 small dents. Replace your bung or stick a dime (or filed down 5p piece) in the hole with a small amount of Araldite around the edge, then take a medium-sized screwdriver and tap the end to knock three small dents around the rim between the original dents. That will hold the bung in place until the Araldite sets.

Then set your valve clearances, check and adjust the carb settings, points, timing and plugs. Your van has backfired so something ain't right - fix it before it backfires again, this time with flames! And when you have time take that fuel filter out of the engine bay and put it where it should be; between the tank and the engine firewall under the van. Flames + plastic filter on pressure side of pump = pile of ashes where van once stood.

Do it yourself - most garages haven't a clue about aircooleds and almost always cock up everything. Just follow the Haynes manual - all is explained.