OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Victa Two Stroke Engines Fuel Leak from G4 Carburetor primer bulb

Help please,anybody! I've just rebuilt a g4 Carburetor from scratch, tried to start the mower and fuel is pouring out of the hole in the primer bulb as soon as i turn on the fuel tap!!! Why?????

Fuel running out from the primer bulb means that the carburetor is "flooding": the float bowl is overflowing. That means the float is not successfully pushing the tiny plastic needle up against its seat in the housing, to shut off the inward flow of fuel when the float rises due to a rising level of fuel in the float bowl. When this happens with a G4 it usually means that the needle has been omitted, or it has been put in upside-down - the pointed end of the needle has to go upward toward the seat, not downward toward the float arm.

(My involvement with G4s has never extended beyond the float bowl).

Thanks again, Grumpy, just re checked the carburetor and the needle had dropped out during assembly! i found an old post by [Censored], who had the same problem in January and he got extensive replies offering advice. Guess the moral of this story is check the forum before posting stupid questions!!!!

Rob, a question can't be stupid if you need the answer and you read the replies carefully. It is a fairly regular event here for people to lose that needle when assembling the carburetor, or to install it upside down. You described the problem so clearly that the most likely explanation was obvious to anyone who had dealt with it before, but not to someone who hadn't.

Please let us know when you get the mower running well, or post further questions if you have more issues. I think you will be rather happy with the machine - I'm a 4-stroke person myself, but the Victa made 2-strokes extremely popular in Australia, and I think you'll see why when you start using it. When working properly it is easy to start, powerful, and reliable, as well as quite uncomplicated when maintenance is required (except for the carburetor, anyway).

Fair comment, Grumpy. I will keep you updated on my progress. Did you get chance to look at the pictures I posted on my welcome thread and, if so, can you identify the machine? Also,it strikes me that there is a lot of potential for air leaks in the g4 carburetor, especially via the kill switch plug. Therefore how important is the air filter on these mowers and do they need to be replaced regularly?

I'll have to leave it to one of the Victa guys - in particular Joe Carroll, but there are some others too who know them all - to identify it. You said it is self-propelled, and that cuts the number of possibilities way down.

Bear in mind that not all of the interior of the carburetor is subject to vacuum, so not much air leaks in through most of the apertures, and the wire should be a decent fit in the kill switch grommets (two wires have to enter separately, and joining them together kills the ignition).

Air filters are very important on mowers, because the engines operate close to the ground, and sometimes (especially in Australia) that ground is dry and the dust rises when the mower blades fan it vigorously to make the cut grass lift up into the catcher. Your particular mower has a snorkel air intake so that the air it draws in is taken from a couple of feet above ground level, and this helps a lot compared with air filters mounted directly on the carburetor. Nevertheless it needs an air filter, it just won't have to be changed very often. (The snorkel-type filter element in my own mower has "2005" written on it by hand. It was in the mower when I bought it second-hand. It looks perfectly clean to the naked eye, but it wouldn't be if you examined it closely. In the British climate yours may last equally long: just take a look at it once in a while, and when it gets seriously dirty, replace it.)

It is a victa pro 505, not a common machine out this way but uses identical motor and carb to the garden variety push mowers.

The carb is prone to vacuum leaks but so long as no corners are cut in my opinion they are a good simple longlasting unit, the cut off wire rubbers should be renewed, both inlet manifold O rings, the O ring under the starter, primer cap O ring and the diaphragm (only if its cracked or particularly sad looking)

Beware of non original primer caps and needle valves, I have come accross quite a few that simply dont seal very well and end up flooding to the point where you have a full tank of fuel inside your engine crankcase.

On a 2 stroke a air filter is extremely important, the dust carrying air not only goes into the cyliner but goes there via the crankcase, dust will get into the bearings and kill the motor in very short order. A filter here is only a couple of dollars and is cheap insurance for the long run.

Once again, thank you, Grumpy. The mower is up and running with no fuel leaks as yet! I have ordered a couple of new parts for the carburetor as insurance against future problems. I do have a problem with the self propelling function, I can't seem to get the wheels to stop turning! I realise this maybe a belt or cable problem so will start a new post and seek further help. Lastly, I'd like to congratulate you on the professional way this forum is operated and the speed in which posts are responded to, well done.

Thank you, Joe, better get me an air filter then! How familiar are you with self propelling mowers? My mower is now up and running but the wheels turn constantly even without pressing the handle. Should I start a new thread for this problem?

Hi Rob.UK, glad the engine is now in good shape. Yes, you should start a thread in the Victa mower frames forum, since this one is for engine problems. A picture or two of the drive control and the drive mechanism would be useful to set the scene when that new thread becomes an archive. Joe is the man once again for the self-propulsion system, and I'm sure he'll respond. As usual, help from anyone who has experience with self-propelled Victas will be appreciated.

albeit owning 3 self propelled victas in the parts pile I have never worked on one but I would suggest llooking into cable adjustment and making sure there is a return spring fitted on the cable at the axle end, I will look closer at one tomorrow and report back.

Hi Everyone,

Just to update this thread just in case if anyone is reading, this might help.
If you are looking for an ultimate solution for the Victa 2-Stroke leaking fuel issue. feel free to see our newly design metal type needle on the link below.

http://www.ebay.com.au/itm/Metal-Ty...retor-with-Rubber-Cone-Tip-/263057735256

Hi Carbymaster, as we all know this has been a problem for a long time but this will only succeed if the price is right. Going to be interesting what pricing you come up with because replacing the primer cap is going to be the killer here as we are all frugal people here and hunting a bargain is part of the fun. The primer caps are floating around on ebay for about $15 each, are yours going to be a similar price? If so plus the needle at $8 gets it up into the not worth repairing range I think. Might be a few people prepared to pay that but the fact the float needle is the reason for these motors not starting is really only known to people who have really studied these carbs. Personally I feel the market for these is probably quite small.

Greetings thecarbymaster,
A most interesting series of initial posts.

Is your metal needle designed as a direct replacement; i.e. compatible with a Victa OEM primer cap?

And if so, which OEM needle length will it replace? The black 10.34mm, or the yellow 10.78mm [overall length] one?

Hi Gadge, from what I read they are still waiting on the new primer caps to be manufactured to suit the needles. I pointed out to him that there had been a lot of discussions going on at ODK regarding the problem so I guess that is the reason for the posts

G'day Norm,
Well, the point of whether their needles could be used at all with OEM primer caps isn't at all clear, from that FleaBay ad.

So I thought it best to put the question directly, and 'on the ODK record', i.e. not by PM.

Hi Gadge, here is the primer cap, even more expensive than I expected.
http://www.ebay.com.au/itm/Victa-Pr...uretor-on-2-Stroke-Engines-/263068374275

Hi Norm,
This does make one wonder if they may have misunderstood the acceptable price points, for their target market...

Hi Gadge, or the market size, as I have said,few people would ever realize the float needle was the problem, it is not an obvious problem. If the needle was not shutting off, that is obvious, but the biggest problem is the needle sticks shut and no fuel flows. This is near impossible to prove because of the primer design so it is always overlooked and people spit the dummy with the mower and give up. As for the market size, even at the price mine costs ( $1.20) I would have thought the numbers I could have sold would probably be maybe 50/100 max if I tried hard so certainly not a big market.This is why I was hesitant about ordering the ones from the States, I figured I would probably end up getting stuck with them. Once I pointed this out to thecarbymaster I haven't had a reply. All interesting stuff.

Looks like Lachlan has decided to off load some of his primer caps. I did give him the info on the new needles and primer caps. $12.50 each is a good price, if only the needles to suit would work
http://www.ebay.com.au/itm/10x-Victa-Primer-Cap-Suits-G4-Carburetor-Carby-/292157192465