I have a 29 van. on a MB SD. It's an '04 model and I have been having nothing but trouble with it since I got it four months ago. I have so far replace the prop shft, rear motor housing, trim unit, belt, throttle calbe, and a number of smaller things that just needed replacing. Anyway, finnally got it out of the shop friday and took it out for some scouting saturday morning and I was absolutely tickled with the way it performed, It ran like it was brand new.....for about 45 minutes. All of a sudden, it killed. I messed around with it for a while and determined that it was some type of fuel problem. I was able to start it and it would idle perfectly fine, however when I would try to throttle it up, it would run out of fuel and kill. I changed my fuel line, changed my quick connect fittings, removed the primer bulb, but nothing would allow me to run over 1300 rpm in the water and about 2000 rpm out of the water. I could get it to throttle up by messing with the choke but it still wouldn't run good enough to run it wide open to get home. I ended up having to iddle all the way home. I was pretty sure that it was a bit of trash in the carb, so first thing this morning, I pulled the carb but the screws to remove the bowl are frozen. So I slapped it back on and started doing a llittle research apparently, alot of people are able to fix those symtoms by adding an electronic fuel pump, so off to NAPA I went. I installed the pump and fired it up to see if that fixed my problem, NO! So, I added some B12 to my fuel and I letting it run for a while to see if that might help but I doubt it will. So to my questions, Anybody got any ideas of what it may be? Also, since the screws on the carb are frozen, I was going to just buy a new stock 35 carb to replace it with however, the carb that I have is the old type with the round canister type filter, and the new ones that SETEX sells looks like the ones with the new style filter.

Thanks in advance for any help

The new carb is the same I'm pretty sure. You just take the adapter off the old one and slap the new one on. I know the old style air filters like you have will work on the newer setup, so I am assuming everything else is the same also.

Thinking really simple here, but is the vent on your fuel tank open?

Yes the vent is open.
Thanks for the tip on the carb.

Is it a 29 or a 31? You sure its a van and not a kawi right?

We did put the 36 carb on our 32 and it was a direct bolt on. All the linkage was the same. The 36 carb originally had the new style air box. Our 32 had the donaldson set up like yours. We put the adapter from the 32 on it, removed the hose and put a k&n directly on the adapter.

I know the 35 carb fits on the 31. I don't know if the 29-31 use the same carb or not, so I would make sure before ordering.

The 36 carb seems to work better on our motor. I'm sure if the 35 carb fits, it would be a good upgrade.

It should be the same carb other than the inlet. It is a big block vanguard. I was thinking about getting rid of the canister and putting a K&N on it but don't know where to get one that's the right size.

I would get an impact driver you hit with a hammer. If it works, great. If not, you were getting a new carb anyway. Get a cheap one at harbor freight. Soak the screws with kroil, it works wonders.

Not to hyjack your thread man but does anyone know if a stock 35 carb would work or be worth it on a 29? I have a 29v GTR and wonder if it would be worth trying to get a little more out the engine.

yeah ima work on it more tomorrow. I may as well break it trying to get it off cause if Icant get it off it's not donig me any good anyway.

r u refering 2 thw screws that hold the bowl on?

yes

ive always had luck grabbing them with a pair of small cutting dikes.

Well I fixed it but now I'm more confused. I got the carb apart this morning and it was clean as a wistle. I put it back on and it didn't fix anything. So I checked the spark plugs and they looked good so put them back in. Then I pulled the fuel hose off the carb while it was iddling to make sure it was pumping properly and there were no air bubbles in it. Then I "jiggled" a couple wires and tried to throttle it up again and BINGO! It worked, so no I don't know if it had something to do with maybe an air pocket in the fuel line that work itself out when I pulled the line, or if it's a loose connectction somewhere. The wires that I messed with was the wires on the little gold looking box with the yellow rubber seal on it, and there is a wire that is spliced into a wire on the main harness. Any ideas of how to pinpoint the problem so I can ensure that it doesn't happen again?

The stuff under the rubber seals are circuit breakers for the clutch and trim- doesn't have anything to do with the engine. Check your kill switch/connections, oil pressure solenoid, or fuel solenoid if you have one.

Thanks for the tips but I don't have a clutch and I have a electrotab trim that doesn't actually have a solenoid. I'll trace wires and see what I can find out. The oil pressure switch seams to be working fine and I'm not sure about fuels switch other than the plug on the bottom of the carb to prevent backfires.