Carburetor Air Box

[Chuck May]

I'm having a problem with the air box top plate hitting against the conical brace on the rear left side. It won't fit flush with the VA-130C mount plate when the bolts go through from the air box top plate, filter, filter plate and the air box top plate. The Mount Plate is flush againt the rear lip of the air box top plate.

My engine is Lycoming 0320 B2C and the carbirator is a one piece CFH-98001 Model 45PA all one unit.

Any Suggestions?

Thanks,

Chuck May

 

[robertahegy]

You don't mention what engine or if you are an "A" model. Here is a shot of my 7A with 0-360 A1A and carb airbox correctly located.

Roberta

 

[gmcjetpilot]

FAB and interference not uncommon

I'm having a problem with the air box top plate hitting against the conical brace on the rear left side. It won't fit flush with the VA-130C mount plate when the bolts go through from the air box top plate, filter, filter plate and the air box top plate. The Mount Plate is flush againt the rear lip of the air box top plate.

My engine is Lycoming 0320 B2C and the carbirator is a one piece CFH-98001 Model 45PA all one unit. Any Suggestions? Thanks, Chuck May

Mr May, I have a tail dragger with dynafocal mount, but I have heard this is not totally uncommon. You did not mention nose or tail wheel. From my memory the O320-B2C mounts the carb towards the back. That may be the problem. I recall that Van A/C does not recommend this engine, for this reason. You may need to change the sump? I'm not 100% sure, but I do know the B2C has a more aft mounted carb location and "straight riser" in sump.

Some sumps do place the carb further aft than others sumps, making the fit problem on nose gear planes (and may be tail draggers as well). In the worst case (and I am not sure exactly what you have) changing sumps may be called for, especially if your top carb plate is hitting the engine mount hard. I don't know if you'll need to change the engine sump, just throwing it out there. You might consider making a new top plate or a whole new new airbox design? Good luck, G.

edit: I sent a private message w/ some other info that may help.

 

[N941WR]

... In the worst case (and I am not sure exactly what you have) changing sumps may be called for, especially if your top carb plate is hitting the engine mount hard. I don't know if you'll need to change the engine sump, just throwing it out there.

Changing the engine sump should be easy. This assumes that the intake pipes are the same, I'm not sure on this one but those parts can't cost that much. Check with ECI for prices.

The sump just unbolts and drops down. You might have to move your quick drain and plug to the new/used sump. The gaskets don't cost that much and all the bolts take 94 in-lbs, if I remember correctly.

 

[Mike Ice]

Wrong sump for RV-7A

Bill, Roberta, George,

Thanks for the posts and answers to my friend Chuck's question.
We have indeed determined that the sump is the problem and a different one will be aquired today and installed soon.

The O-320 B2C is a good engine but the sump places the carb too far back and causes clearance problems for the nose draggers front gear leg.

If any of you folks ever get to Anchorage let us know, we will provide a welcoming committee.

Mike Ice

 

[N941WR]

Mike,

You MAY have to change the oil pick-up line when you change the sump. You will know as soon as you match up the new sump.

BTW, check eBay for a replacement. You might get lucky. (or unlucky)

 

[Mike Ice]

wrong oil sump

Bill,

Alaska has a rich aviation history and parts abound here in Anchorage. One of the locals had over 10 sumps ready to go. Thanks anyway for the suggestion.

I will look into the oil pick up tube.

Mike

 

[Jconard]

changing from the early aft-mount vertical induction sump to the newer style will require:

1. 4 new intake tubes.
2. Remove the pipe plug on the oil galley on the accessory case. This is located in the bottom sealing surface where the accessory case meeets the sump. Oil will be drawn from here rather than through the oil pipe.
3. Remove the oil pipe which is bloted to the accesory case. It is held on by two bolts right below the oil pump
4. Find a way to block off the hole where the oil pipe was. Many simply cut the flange off the oil tube, weld it up, and bolt it back on.

 

[Mike Ice]

O-320 B2C wrong for RV "A" models

The saga continues. Chuck found out yesterday to make the O-320 B2C work in his 7A that he would also have to change out the accessory case. So now the parts count in $$$ is up to around a 1000.

I guess this is the good reason why Van's doesn't recommend this engine.

We are looking into other alternatives before we spend the $$$.

Is it possible to build or manufacture a different airbox system??

Mike Ice