Air box fit

[58Evinrude]

Are the carbs supposed to fit into the airbox holes? On my 78 there is no way they will fit.. I've tried oil on the carb ends, twisting, no way will they fit. 

[Interceptor398]

The air boxe bottoms are all the same.  Intruders suck air from the right and the rest from the left.  Drifter are some else entirerly. The carb adaptors are sized to fit the carbs used on the different sleds, 340, 440 Invaders & 4/6, Intruders and LTD's.  It sounds like you may have an air box from a 340 Invader or an Intruder?

[58Evinrude]

It sucks air from the right hand side, and it has the brace off the gearcase to hold it up, so I'm guessing it's the right airbox. I was wondering if the rubber adapters in the holes had shrunk, and won't let the carbs fit. What size carbs are on a 340?

[Interceptor398]

What sled is it?

[Lloyd (ljm)]

 His sled is a 78 Intuder

[jimvw57]

There are different rubber boots that go between the carbs and the airbox. 440 Invaders use a 36mm carb, the 340 uses the 34mm carbs.

for some reason I can't get into the supporting member area to say whet the Intruders use, but I'd guess you might have an airbox for a 340.

 

[58Evinrude]

What's the purpose of the black plastic rings that go around the carb inlets? To stop the carbs from going too far into the airbox?

32 and 34 mm Mikuni's have the same outside measurements. At least the carbs I have here are the same.

[gixxer6]

The plastic rings are there to support the air box.  Otherwise it rests against the plastic elbow (on power jet carbs) and can break it off. 

36mm carbs have a larger OD than the 32 and 34mm carbs. 

[Interceptor398]

What's the purpose of the black plastic rings that go around the carb inlets? To stop the carbs from going too far into the airbox?

32 and 34 mm Mikuni's have the same outside measurements. At least the carbs I have here are the same.

1978 340 Invader carbs are marked 32/122
1979  and 1980 are marked R32/139
Intruder carbs are "econo jet" carbs and are stamped with 1978= L32/120 & R32/121.  1979 = L32/141 & R32/140.  1980 = L32/164 & R32/163.  1981 = L32/185 & R32/189.  1982 = L32/185 & R32/189. Note the left and right stamping, the difference is jetting.

[thomy]

What's the purpose of the black plastic rings that go around the carb inlets?

The rings seal the carbs into the airbox to reduce the entry of snow. Without them the engine is likely to run leaner than with them.

[gixxer6]

What's the purpose of the black plastic rings that go around the carb inlets?

The rings seal the carbs into the airbox to reduce the entry of snow. Without them the engine is likely to run leaner than with them.

The rubber grommet/seal on the air box does the sealing, the plastic ring is a mechanical support. 

[58Evinrude]

OK, I've got it figured out. The rubber rings that seal the carbs to the airbox were shrunk with age. I guess they hadn't been on the carbs for a while. I stretched them out, and they fit.

[thomy]

What's the purpose of the black plastic rings that go around the carb inlets?

The rings seal the carbs into the airbox to reduce the entry of snow. Without them the engine is likely to run leaner than with them.

The rubber grommet/seal on the air box does the sealing, the plastic ring is a mechanical support.

Sorry, I thought he meant the rubber grommets the carbs fit into on the airbox. I forgot about the plastic pieces.