Will a lycoming 0235 fit using the cowl?

[gizmos]

I have my mount set up for the rotax 100 but looking for a better price engine choice. What or will 0235 fit my cowl? What engine mount? I like the rotax 100 hp but I have a hard time on the price. If anyone has a good used rotax, Please let me know. Need to get my fox to Wickenburg this year

[Av8r3400]

There was a nice used one for sale on this board just a few days ago. $6500...

[N981MS]

The O-235 and IO-240 are wider and will not fit in a rotax cowl. In fact the O-235 requires nose blisters for a little extra clearance vs the IO-240 all smooth cowl.

I initially ordered the O-235 cowl but removed the blisters when I wound up with the IO-240.

[jtpitkin06]

You are talking about a complete firewall forward package. The Lyc O-233/235 will not fit under the Rotax Cowl. The Lyc is longer and wider. Kitfox sells a wider Lycoming cowl with the blisters to clear the valve covers. As for the mount Kitfox also has a Lycoming mount available. Engine mounts are not interchangeable.

The Lyc uses a different prop bolt circle from the Rotax 75 mm bolt circle. The Lyc is either a sae-1 or sae-2 pattern.

If you are installing from scratch, the installation with a Lycoming should be about the same labor as a Rotax. Cost is really about the same. You'll get a bit more power with the Lycoming, up to 115 hp, but you pay a weight penalty.

No free lunch.

[PapuaPilot]

Another consideration that could be a make or break is your wing sweep. On the Rotax installation you set the wing with zero sweep. If you put a heavier engine on then you should have a 1 degree forward sweep on the wings. The sweep of the wing affects your CG envelope could make it very difficult to get inside the CG envelope.

Here is the data I found for the Series 5 & 6 Kitfox

NO WING SWEEP
Max. Gross Wt.=1550 Lbs.
Max. Forward CG=11.37"
Max. Aft CG=16.00"

1 DEGREE FORWARD SWEEP
Max. Gross Wt.=1550 Lbs.
Max. Forward CG=9.96"
Max. Aft CG=14.75"

[gizmos]

Thanks for all the info, I am calling the one for $6500. I guess I will stay with the rotax 100. A little concerned about the 2100 hrs on the engine, but with great compression. I may have to do a rebuild soon, I have been told to expect $5k to $8k on rebuild. May be going down the wrong road