1956 Lark 30 vs. 1958 Big Twin 35

[54fleetwin]

I alread have the lark and am driving 4 hours tomorrow to get the big twin.
Please share pros and cons of each
TIA,
Steve

 

[F_R]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

There isn't a heck of a lot of difference in them. A bigger bore in the Big Twin makes 5 more horses.

 

[1946Zephyr]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

Yep, they're pretty much the same motor. The 35's had the compression releases on the heads and a 40.5 CID, whereas the 30's had a 35.7 CID and a standard head. Pretty much everything else is the same.

 

[54fleetwin]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

Does the '58 big twin have a thermostat?

So no weight difference and the 95% of the parts interchange?
Engine was put in storage in 1960. Did I mention it comes with the pressure tank?

 

[jbjennings]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

I don't believe any of these stories about these "motors" without pics....
JBJ

 

[F_R]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

'58 Big Twin 35 DOES NOT have a thermostat
'58 Lark 35 DOES have a thermostat

Weight difference between 30 and 35 Big Twin is minor

95% of the parts is approximately correct. They are not "identical" motors.

 

[lindy46]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

'56 Lark has a 6 volt starter and choke solenoid, 58' if equipped with electric start would be 12 volt.

 

[samo_ott]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

The '56 30hp 35.7 cu in block was around for a long time (early 50's to mid 60's). It was a 25, 30 and then 28hp model. Parts are plentiful. Viking used it after OMC also. The 40.5 cu in 35 hp was only used for 3 years ('57-'59) and then later used as the 33hp model. Parts are around for both. I have a lot of 35.7 cu in blocks/engines so have an affinity for them.

4 hours is a long way to go. It must be a good deal or in great condition!

 

[54fleetwin]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

4 hours is a long way to go. It must be a good deal or in great condition!

Its stuck in gear, no matter I have lower end parts laying around.

Price ended up being FREE.
Came with 6 gal pressure tank and original owners manual.


I wish you guys had told this uses a quick disconnect wiring harness.
Thats missing.

 

[54fleetwin]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

 

[F_R]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

Um, wiring harness?? Did you mention it being a Big Twin Electric?

 

[lindy46]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

Wow! Pretty nice looking motor. And you can't beat the price

 

[54fleetwin]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

Um, wiring harness?? Did you mention it being a Big Twin Electric?

ummmm....No
I assumed it was.
The wiring on my Lark is different, thats what I was expecting
Found out why it wont shift or turn over, rust in the lower unit.

Are these big twins the same as my 7.5 fleetwin, in which I have to remove the powerhead to disconnect the shift rod?

Will this engine run without the wiring like my Lark?
If it can, I will use it w/o electric start for now.

 

[Chinewalker]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

Your new 35 is a sweet motor! The plastic medallions look to be in great shape! They're usually sun crazed or broken or missing entirely! Nice find!

Shift - no, you do not need to pull the powerhead. The small oval plate on the side of the motor leg reveals a brass shift coupler. Remove the bottom bolt to disconnect the shift rod.

Running - yes, it will run just fine with nothing plugged into the side.

 

[54fleetwin]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

Chinewalker, I assume the lowerunit from the '55 BT25 is the same and I can rob parts from that?

Now to figure out which one to keep and use.
The Lark 30 is running but needs the lower seal kit and impeller, same on this BT35.

BTW, the pin wont come out of the prop on the 35

 

[tmcalavy]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

Fix them both up and run twins...like this (pix).

 

[Mas]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

Nice motor...I'd driven further for that price.

Mas

 

[54fleetwin]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

Well I broke 2 of the stainless steel screws that hold the waterpump housing

 

[samo_ott]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

They drill out.

I'd drive 4 hours for a free big twin also! Looks good.

Hope it's just the LU thats stuck and not the powerhead that's seized. Sometimes it's hard to tell until you separate them.

Any chance you're going to be scanning in that owners manual? I'd love a copy if so!

Also, you can hard wire your own harness in and yes, it will run fine without the harness. You will have to choke it to stop it though.

 

[1946Zephyr]

Re: 1956 Lark 30 vs. 1958 Big Twin 35

Um, wiring harness?? Did you mention it being a Big Twin Electric?

Yea, as a matter of fact, there is a plug in, on the starboard side of the motor, to accept a wiring harness. Kinda like the one the '57 Javelines used.

The lower unit should be the same as the one on the '55 Big Twin. I do believe the '55 had the large bolt one the rear, as well as the 6 smaller ones, like your '58 does. 54 and older were made without the larger rear bolt, but I have actually seen them used on the later motors.