Jacobs R-755

Thu Mar 12, 2009 10:10 pm

Hello folks:

Does anyone know the weight of the Jacobs R-755? Couldn't find the info anywhere.

Thanks

Thu Mar 12, 2009 10:21 pm

About 450lbs with the carb, sparkplugs, generator and control box, ignition wires, prop centering cones and nut and oil strainer.

Thu Mar 12, 2009 10:23 pm

Thanks Waco YKC.

Thu Mar 12, 2009 10:34 pm

What's the diameter?

Fri Mar 13, 2009 4:52 am

Hi A2C,

I am refering to Jacobs installation diagram for L4MB (same as R-755-9), diameter is 43 1/2", length is 41 15/32', mounting ring PC 16 1/2" (8 x 25/64" dia holes), C of G 5 1/8" fwd of mounting face, total dry weight 473 Lbs (includes magnetos, unshielded ignition wiring and plugs, carb, prop centering cones and nut, oil filter).

In addition to above weight, E-80 starter + 19 1/4 Lbs, Breeze radio shielding + 10 1/2 Lbs, prop hub + 15 Lbs, Eclipse generator + 15 1/4 Lbs, Romec fuel pump + 1 Lb 10 ozs, Romec vacuum pump 4 Lbs.

It all adds up!

Howard

Fri Mar 13, 2009 7:45 am

Avro Biplane wrote:Hi A2C,

I am refering to Jacobs installation diagram for L4MB (same as R-755-9), diameter is 43 1/2", length is 41 15/32', mounting ring PC 16 1/2" (8 x 25/64" dia holes), C of G 5 1/8" fwd of mounting face, total dry weight 473 Lbs (includes magnetos, unshielded ignition wiring and plugs, carb, prop centering cones and nut, oil filter).

In addition to above weight, E-80 starter + 19 1/4 Lbs, Breeze radio shielding + 10 1/2 Lbs, prop hub + 15 Lbs, Eclipse generator + 15 1/4 Lbs, Romec fuel pump + 1 Lb 10 ozs, Romec vacuum pump 4 Lbs.

It all adds up!

Howard

I'm pretty sure the L4 is larger in diameter than the R755A and B's. When they mount those on the 195 it requires a cowl mod and it sticks out on the sides. (The original post didn't specify model)

Fri Mar 13, 2009 10:41 pm

You must be thinking of an L-6 of 330hp. The L-4 was 225hp upgraded during WWII as a R755 to be 245hp. After WWII it was upgraded further to be 275hp. You cannot hardly find an L-4 and why would you? You can order an overhauled 245 or 275 from several places. I have had both the 245 and the 275 on my Waco.

Sat Mar 14, 2009 7:24 am

wacoykc wrote:You must be thinking of an L-6 of 330hp. The L-4 was 225hp upgraded during WWII as a R755 to be 245hp. After WWII it was upgraded further to be 275hp. You cannot hardly find an L-4 and why would you? You can order an overhauled 245 or 275 from several places. I have had both the 245 and the 275 on my Waco.

Yes I was thinking of L-6 sorry.
Most 245's have been changed to 755B-2 configuration by now (considered to be the finest Jacobs as I understand- really more than 275, while the A-2 is really less than 300hp)and with the option for fuel injection, better than ever.