Lawn-Boy Model 'E' Twins (mockup)

[Fast Eddie]

Thanks again Russ. I appreciate your knowledge. Sounds like if I don't get lucky and find a couple of electric start engines, I'm going manual.

I've done some looking and I've found a few mowers in the $150 to $175 range. Is that too much $$? I also saw L-B has horizontal shaft Duraforce engines for a snowblower application-all of which seem to have electric start. Ever see those around used?

If anyone has a Duraforce or two they want to get rid of, let me know. I'm in the Detroit area and can drive a couple hundred miles to pick up or I can arrange shipping.

Sorry for the hi-jack Russ.

 

[Russ2251]

...found a few mowers in the $150 to $175 range. Is that too much $$?

Depends on your budget. Of the 4 I purchased off Ebay, non were over $150 delivered. I have paid as little as $75 delivered.

I also saw L-B has horizontal shaft Duraforce engines for a snowblower

They are actually Briggs and Stratton manufactured engines.
I have 2 of them (new in box) I purchased about 1½ years ago @ $120 each. These are piston ported engines and don't carry the punch of the reed ported engines found in the L-B manufactured mowers.
I mounted one to a Fox mini bike and the other to a one wheel drive yard kart.
Performance was ok but was lacking top end rpm/power.
Be aware that I could only find 1 clutch that will work/fit on these engines (mower or snowblower). Noram clutch #160157 available here and installed (see attached pic) on a model V L-B engine.
They ain't cheap and stops most (all?) folks from pursuing this conversion any further.

 

[Fast Eddie]

What's the issue with clutch selection? Bore dia?

Budget-wise, I'm trying to stay well under $600 for two engines, complete with clutches, carbs and engine mounts. That's quite a bit less than what it would cost me to run dual Macs or something more period-correct. I have access to a waterjet so cutting the mount parts and welding them together is no issue. I can probably get two good rebuilt Tillys for about $100 total. So that leaves me a little under $500 for two engines and clutches. But obviously, the cheaper the better.

 

[Russ2251]

What's the issue with clutch selection?

Bore diameter is one reason.
The other reason is that crankshaft end does not have an internal bolt hole (5/16-24 typically) for securing an outboard clutch. Because of this, clutch must be bi-directional (inboard/outboard) and is secured with set screws.

On my yard kart, clutch is outboard.
On twin gokart and mini bike, clutch must be inboard.
Large bore diameter means that sprocket cannot have less than 17 teeth, assuming the use of #35 chain.

I lucked out on carbs. A guy on Ebay used to sell NOS Tillotsons for around $30. Have not seen them for many months now. Good thing I stocked up on them.

 

[anderkart]

Large bore diameter means that sprocket cannot have less than 17 teeth, assuming the use of #35 chain.

Hey Russ, I'm always interested in 1" clutch posts cause I have a couple engines that use em and I've spent countless hours searching the net soaking up info. I had a couple thoughts here I just wanted to bounce off ya here to get your opinion:

First, I searched around and noticed the 1"/#35, 1600 series Norams do in fact only come in 17 tooth models and no one else seems to make any other set-screw type, (able to inboard or outboard mount) with diferent gearing options in a #35 size driver.

I was wondering if these Lawn-Boy cranks seem to be likely candidates to simply drill/tap a clutch retaining bolt hole?
If so, this 1"/#35 Noram model is avalible with your choice of 13 to 18 tooth drums and are designed for inboard or outboard usage: http://www.kartpartsstore.net/servlet/the-337/The-Noram-Star-Clutch/Detail
(13/14-tooth models have a bushing for clearance reasons, 15 through 18 tooth drums come with a nice needle bearing)

Admittedly these do cost even more than the 1600 series but I was just thinking with modding the crank, this model could be used for alternative gearing options on a L-B or possibly any other 1" pto w/o a tapped hole.

Instead of modding the crank, another option I was kinda wondering about is if you thought a strong steel lock collar could simply be used to retain a non-set screw type clutch, mounted inboard or outboard on a L-B? (meyby with either just a washer or a thin flat thrust bearing sandwiched between 2 thin thrust washers, and instaled inbetween the clutch and lock collar)

Whatcha think?

 

[Russ2251]

seem to be likely candidates to simply drill/tap a clutch retaining bolt hole?

Could...but for me just adds to the total cost. $omething I'm trying to avoid. I could do it my$elf but don't have the tooling required.

this 1"/#35 Noram model is available with your choice of 13 to 18 tooth drums and are designed for inboard or outboard usage

I don't see where it says inboard or outboard and may not be possible.
I originally experimented with 1" bore direct drive sprockets and 17 tooth is smallest available. Diameter of sprocket (hence number of possible teeth) is the limiting factor in conjunction with bore size.
In other words...smaller bore can have less teeth to fill available circumference. 16 teeth will not fit on a 1" bore sprocket/clutch (maybe 7/8's?) and remain inboard/outboard (or bi-directional). Circumference is too small. Difficult to explain unless seen "hands on".

 

[anderkart]

I understand, you got a better price on your clutches and probably didnt want the smaller driver sizes anyway.
Did you have any thoughts on using a lock collar instead of a crank bolt to retain a non-set screw type clutch? (I was thinking as long as the shaft was long enough and the set screws stayed tight it should work just fine)

I respect your knowledge and I'm not trying to be argumentative here at all, but I'm pretty sure I've got all my facts streaght on this Star model. I'm running a 13 tooth Noram Star on my karts 1" pto right now. Over time I've also acquired serveral extra used Star drums w/built in drivers ranging from 15 to 18 tooth. All the diferent driver options of the Noram Star series are definitely made for 1" pto's. The smaller sized gears just end up much thinner where the large 1" bearing or bushing sizing has been machined out.

According to a Noram rep I asked, this clutch model and all the diferent driver sizes avalible for it are rated up to 20hp and will usualy handle quite a bit more. They specially made the smaller gear sizes avalible to allow corect gearing for some of the smaller sized oval tracks.

This Noram model was designed and sold especially for the 1" pto bore Tecumseh Star race engines but I ran this same clutch on my old Honda's 1" pto too. I know Norams limited info on this model doesnt specificly state it can be ran inboard but I did some serious research on this particular clutch and inboard is absolutly the preferred mounting method with the guys that have built and raced these Tech Star's for years and years since the mid 90's. They all said inboard puts much less strain on this engines relatively weak pto and the clutch is designed for (and works just fine) mounted either way. The only reason I went outboard on mine was my karts 3'rd axle bearing hanger was in the way of ever lining up to the rear sprocket. (my kart also would have needed much more seat clearance when mounted inboard)

Here's my 13 tooth Noram Star all mounted up on my 1" pto:

 

[Russ2251]

I'm running a 13 tooth Noram Star on my karts 1" pto right now.

And it will fit on shaft inboard as well?

 

[anderkart]

Yep, for more clearance, my 13 tooth drum (and the 14) uses a thin walled 1" ID bushing instead of the needle bearings the 15 through 18 tooth models have. All my drums/hubs will side right on in either direction.

The real trick to making this all work is you have to use their special key.... Half the length of this bezaro key has been precisely machined down to only just fill in the pto's keyway slot. When instaled outboard, this makes the last outer inch of the pto a complete void-less surface for a bearing or bushing too fully ride on. To install inboard, you just slide the whole clutch on first, and then slide the key in pointing the opposite direction. They want you to set up your retainer bolt, washers/spacers so this clutch can float in and out, 3/16" or so on the pto.

Ive fully instaled this same key w/clutch mounted inboard on both my 1" Honda and Tec star engines. While I never actualy rode the kart mounted inboard, I have no doubt those shoes would still move on out and get a grip. Everything seems to be designed to work inboard or outboard.

This link has a bigger pic and shows a 14 tooth w/bushing: http://www.out2win.com/catalog/images/star.gif

 

[Fast Eddie]

Hey Russ...sorry to hijack your thread again.

I've decided to go with the twin L-B's as well. Going tomorrow night to look at a non-running mower for $85 on CL. He says it has spark and compression (not measured with a gauge), but gas just pours out the exhaust. Said he's had carb trouble since day one and has had it in the shop a few times. He mentioned something about an issue with a "crossover pipe". Nothing I have to be concerned about since I'm switching carbs, right? What would you pay for something like that?

Yes, it's a 6.5hp DuraForce (non-electric start...bummer).

 

[Russ2251]

L-B's exhaust used to be directed toward the ground.
A new exhaust system was introduced in 1998 that used a crossover pipe that redirected exhaust to muffler mounted on top of mower deck.
I assume this is pipe he is referring to. If that is the case then, yes, carb is bad.
A bad float would cause crankcase to fill with raw fuel and ultimately pour out of exhaust.
$85 sounds reasonable, but I would still try to get the price down. After all...it is a non running engine.

 

[Fast Eddie]

L-B's exhaust used to be directed toward the ground.
A new exhaust system was introduced in 1998 that used a crossover pipe that redirected exhaust to muffler mounted on top of mower deck.
I assume this is pipe he is referring to. If that is the case then, yes, carb is bad.
A bad float would cause crankcase to fill with raw fuel and ultimately pour out of exhaust

That's great news. Was hoping that was the case.

$85 sounds reasonable, but I would still try to get the price down. After all...it is a non running engine.

My thoughts as well. From the pics, it looks real clean. But again, it doesn't run.

Thanks again, Russ.

 

[Russ2251]

Inching ever closer to the goal:

 

[Fast Eddie]

This could get you an extra .211 MPH

 

[Russ2251]

Wouldn't that be cheating?

 

[Rickracer]

Not unless you hide it. I always say don't bring a knife to a gunfight, run whatcha brung and hope ya brung enuff,

 

[Fast Eddie]

Wouldn't that be cheating?

Nope...just thinking "outside the box".


Can't find that specific Tillotson HL you've been referring to. Found other HL's but not the one you used. Got any sources?

Also, did we find out for sure if 1) the Noram Star can be mounted inboard or outboard and 2) if I can cut off the crankshaft and drill/tap for a clutch retaining bolt?

Model "E" twin #2 is underway.

 

[Russ2251]

Can't find that specific Tillotson HL you've been referring to. Found other HL's but not the one you used. Got any sources?

Unfortunately, no.
I bought up what I could when they were available. Most I've put into service on various projects with a couple for back-up.
I'll see if I can come up with good replacement.
If you do come up with something, make sure it's a fully adjustable (high & low speed needles) carb.
EPA emissions compliant carbs will not work. Which reminds me...I going to post something regarding "global warming/climate change" in Off Topic Fun.

 

[Fast Eddie]

Unfortunately, no.
I bought up what I could when they were available.

Is there any other HL's that will work? What do the numbers represent-CFM? I saw an HL300-something. Want to get the clutches and carbs ASAP.

 

[Russ2251]

Is there any other HL's that will work?

Unknown at the moment. As previously stated, I will look around and see what I can come up with.

What do the numbers represent-CFM?

Unknown, but unlikely it is CFM.