C-85 Long engine mount or Short

[crispy critter]

Re: C-85 Long engine mount or Short

How do you tell if you have a short or long engine mount? Why are there two different sizes? What was the purpose?

Dennis,
To answer your question, the short mount is 8 inches from the firewall to the front surface of the mount where the engine mount rubber sets against it. And if memory serves me correctly the long mount is 12 inches measured the same way.

For sme of the other questions...As mentioned above, you can fit the light weight B&C or sky tech starters between the firewall and engine with the short mount but it is tight(check out cvavon's pics). You have to pull the engine off or at least take it loose enough to move it forward about 8-10 inches to install the starter. The small orange light weight B&C alternator can be installed without taking the engine loose.

Now about the long mount.... Unless something has changed that I'm not aware of, the long mount requires the gross weight increase taking it out of LSA category. It also requires you to mount the battery in the very aft section of the large style baggage compartment for CG reasons(I forgot the station number). If you go with the long mount it does change the flying characteristics of the airplane quite a bit. Its no secret to most that I prefer the short mount. Also, the 0200 is not approved in the STC on the short mount but if you have a FSDO that will work easily with you its not hard to get approved as long as you do all the required mods to the spar bushings, struts brackets, and fuel lines. If you need previously approved data I can send or post copies. I have an 0200 on a short mount but I don't have it approved for the starter and alt yet but have someone who said they would e no problem when Im ready to add them. Also to stay legal on the short mount you have to stay with the small baggage compartment and your max gross weight is limited to 1280lbs.

I hope this helps and some of this might have changed as for the 0200 stuff on the shot mount that I'm not aware of but I'm sure Terry Bowden can answer that stuff for you.

[cvavon]

Re: C-85 Long engine mount or Short

Kevin the sky teck will not work as it will hit fire wall if i remember it's almost i inch longer then B&C it will hit.Also to remove the starter all you do is take the top mount bolts off, loosen the bottom bolts and lower the engine about 2 or 3 inches and out it comes.

[astjp2]

Re: C-85 Long engine mount or Short

I put a battery on the firewall on a couple of F-19s, CG was still good. The long mount does not require the gross weight increase, the gross weight increase requires the long mount.

[cvavon]

Re: C-85 Long engine mount or Short

With the Oddyssey battery on fire wall and starter,alternator on a short mount the CG on my plane is 18.97 the empty weight is 777 pounds the main wheels weigh 708 lbs and the tail wheel weighs 69 pounds and it flies like it did when it had the A65-8F on the front, only climbs better and is a little faster oh and gets off the ground quicker.

[astjp2]

Re: C-85 Long engine mount or Short

With the Oddyssey battery on fire wall and starter,alternator on a short mount the CG on my plane is 18.97 the empty weight is 777 pounds the main wheels weigh 708 lbs and the tail wheel weighs 69 pounds and it flies like it did when it had the A65-8F on the front, only climbs better and is a little faster oh and gets off the ground quicker.

Is that a PMA'd battery box? I use Burls because they are an approved part for the Sedan and the oddessey battery.

[cvavon]

Re: C-85 Long engine mount or Short

Owner produced we made it our self

[crispy critter]

Re: C-85 Long engine mount or Short

Cvavon, You must've had a different model of sky tech, I've seen two short mount tcrafts with sky techs on them.

As for the battery location and gross weight requirements for the long mount....I'm going by memory but I would double check that if I were you.

[cvavon]

Re: C-85 Long engine mount or Short

at the time that i put the engine on my plane sky teck had one starter that fit C85 it was longer then B&C by about 1 inch and if you look at the photo of my install 1 inch would not get it. I cant find my numbers but i did look at sky teck and it looks like they changed there motor on there starters witch could allow them to fit. The numbers are from my plane and the re-weigh that was done after the engine change. I don't have a long mount. Ok found my numbers and these are form Sky Teck and B&C's web sites the only starter Sky teck lists for small Continental is 6.4 inches from the face to the end of the case.The B&C starter is 5.70 from the face to the end of the case. That is .70 in. witch is 7/10 in. so with the B&C installed on a short mount the gap between the starter and firewall is 5/8 in. the sky -tech will hit the fire wall or get the hammer out and put a big dent in the firewall.Or you could shim at the mount to firewall attach point or the engine attach point witch moves the engine forward then all kinds of things don't fit. B&C is a bolt on and requires no other mods.

[crispy critter]

Re: C-85 Long engine mount or Short

The sky tech didn't touch the firewall but it was so close it wasn't funny....the b&c certinly gave a little more comfort space between the firewall and starter.

[barnstmr]

Re: C-85 Long engine mount or Short

I understand that the extended engine mount causes the airplane's handling to be a lot different.

[crispy critter]

Re: C-85 Long engine mount or Short

It really does Terry.....the F-19 flies more like a C-120 then a taylorcraft.....don't get me wrong, it's still a great flying bird with good performance but flies nothing like a short mount taylorcraft in my opinion.

[astjp2]

Re: C-85 Long engine mount or Short

I know that you can put 200# in the baggage of a short mount airplane with 100 hp and still have a good CG even if its 500 over gross. Tim

[crispy critter]

Re: C-85 Long engine mount or Short

Yep, and it will handle it with no problem. However because it's not legal the FAA will have a field day with you if ya get caught doing so or have an accident.

[Pearson]

Re: C-85 Long engine mount or Short

.....the F-19 flies more like a C-120 then a taylorcraft....

I used to fly a friend's F19. It flew just fine, but the big difference between it and my stock A65 BC12D was on landing. As you slowed to to flare, it would get nose heavy. And that was after trimming during final. I am talking about the last 2-3 seconds just before you touch down. If you tried to hold it off too long, it would just stop flying and drop down to the runway. This was with two 180 - 190 pound guys and no baggage. His plane had the O200 with starter and generator. I don't recall where the battery was located, but the plane was just a tad nose heavy with nothing in the baggage compartment.

I am planning on using the long mount on my project plane that is getting the Harer STC. But since I plan to use the light weight versions of the starter and generator, I am wondering if I should mount the battery at the aft end of the baggage compartment, or possibly move it a little forward such as just under and behind the seat sling. Has anyone done any W&B computations on this they would care to share?

[cvavon]

Re: C-85 Long engine mount or Short

Rich why not stick with the short mount and do like i did put the battery out on the fire wall. The group on supper cub were talking about a new battery that is just hitting the market that is 620 CCA and only weighs almost 3 LBS. It is 11 LBS. lighter then the oddysey i have on my tcraft witch is 14 LBS. Check post 19 of this thread my CG and weights are there.