I purchased a used brison 5.8 the older green case one. I got it on the plane and let it set for 4 years or so, never ran gas thru it at all. Today I tried to fire it up and the carb is not pulling fuel from the tank. This is my first gasser to play with so Im not sure about a few things. Does the tank need to be pressurized? There is a nipple on the side of the motor, what is that for? Any help would be greatly appreciated. I did take carb apart and cleaned it. Its the walbro carb wasn't gummy or dirty or anything inside, all ports are nice and clear.

If the engine has been unused for so long you will have to change the diaphragms, gaskets and mertering needle in the carb. Look on the body of the carb. There are some letters and numbers on it. What are they? Go to this website to find the correct rebuild kit and exploded view for your carb. Dan.

Do you know where to get the gasket for the block between the head and the carb?

I always make my own from some card stock

Try Bill Jensen. Dan.
[email protected]

Thanks guys, I checked all the local small engine repair shops and nobody has the rebuild kit for the carb so I guess I will be ordering off the net this week. I just hope this is the reason the carb wont pull fuel. Thanks again for the help.

You mentioned a nipple on the side of the engine. Where is this located on the engine and is it capped off or open? Likewise, are there any unused fittings on the carb? The only two uses I could think of for a nipple (line fitting) on the crankcase would be (1) to supply crankcase pressure pulses to the pump side of the carb or (2) to supply crankcase pressure pulses to a smoke system. In the case of a smoke system, it would be differential pulses to a pump of the type that Bennett use to sell or simple crankcase pressure to a smoke tank. Either way, if no smoke system is used, this fitting should be capped off. If used to operate the pump in the carb, there would be a corresponding fitting on the carb. There should be a line between the case fitting and the carb. Most of the Brison engines used pump pulses supplied through the carb spacer but there are exceptions.

As your looking from the front of engine with cylinder facing downward its on the right side of the motor in the crank case, right now its open. There are no extra nipples or anything on the carb, its a walbro sdc 80 carb. Should the plug on the side of the engine be capped off?

Easy to check. Put a short piece of gas line on it with a plug or a big machine screw in it to seal the other end. If it fires you are good if it dosen get a carb rebuild kit. Warbro makes a general rebulid kit that will fit that carb (and about 200 others).

I tried to cover it and it still didn't pull fuel. So I guess a rebuild kit is next. The diaphrams don't really look bad but are dried out a bit.

Wet them with a little gas, clean out the carb orifices with some spray carb cleaner and put it back together. It will probably run fine.

Yes, if the fitting on the crankcase is open, it needs to be capped of. If left open you will have one huge crankcase leak and if the engine runs, it will be impossible to make it idle correctly with the hole open.

With the vent nipple open, I doubt the engine will ever do anything but pop at the most and will never actually run.

www.ereplacementparts.com has every walbro carb rebuild kit you could ever need.

Pull the carb off, there should be a small hole that passes through the insulator block ( about 1/8" ) this is the crankcase pressure port make sure the gaskets on both sides of the block do not block this port. Make sure that the hole lines up with the hole in the carb and the hole in the crank case.

When plugging the hole on the side of the crankcase use a bolt that is only long enough to penetrate the case or at least be sure there will be no interference with internal parts when the bolt is seated . If the engine has been sitting for several months the diaghrams in the carb get stiff and the needle can get stuck seated as well . I would go ahead and install a carb kit in that SDC 80 carb . BTW sure to get the correct kit for an SDC 80 (K10 SDC)

Im ordering a kit for the carb and gonna figure out what to do about the carb spacer gaskets, hopefully I will have this thing going in a week or so. Thanks for all the help guys.

Be careful when choosing the parts from a Walbro rebuild kit. There are a lot of parts in the kit that are not used for your carburetor and they all look very similar to each other. That carb has a forked metering needle lever that has to be engaged properly with the metering diaphragm. Also follow that exploded view during the reassembly. The gaskets and diaphragms do not go on in the same order on the opposite sides of the carb body. Dan.

Thanks Dan I will remember that.

Well I called around to a few places today and finally found a small engine shop that had the K10-SDC kit in stock so I rushed over and got it since it was the last one they had. I also stopped by the automotive store and bought some gasket making material and made a new set of gaskets for the spacer block. Just finished it all up and got carb remounted. within 2 flips of the prop the fuel is now heading to the carb. So hopefully tomorrow I will fire this thing up and it will run on its own. Thanks again for all the help with this thing. I really do appreciate it.

Glad you got it going.

Well its not going yet but lookin better for me. Last time I tried I could get it to fire if I put gas into the carb but once that bled off there was nothing in the lines to keep it running. But now it is pulling fuel so its a step in the right direction lol.

Want to thank everyone for the help on this engine. I was able to finally fire it up today. It seems to run pretty good, just need to get a tach on it and tune it. Now to find a decent smoke pump and Im almost ready. Thanks again.

+1

I'm glad you got it running . It should give you years and years of service. I've never seen one worn out . Broken and damaged yes
but never worn out......