Repower '84 Woodmizer LT-30

Auminer · May 30, 2014, 03:42:28 PM

Since I'm layed up for a while, I'm thinking I'd like to upgrade my old 14 hp Kohler to a ~25 hp Honda. I'm getting old and don't have time to waste waiting for a cut. ;D
Looking for suggestions, experience from those that have converted, or anything I may have overlooked.

Dave

Dave Shepard · May 30, 2014, 03:44:49 PM

I converted a '92 LT40 from electric to gas. The engine I used had an odd bolt pattern and shaft size, so there was a bit of customization required. In the end, it worked out very well, but took some fine tuning. My first call would be to Wood-Mizer to see what parts they have that might make the swap easier. They might even have an upgrade kit for that mill.

pineywoods · May 30, 2014, 08:11:59 PM

Auminer, I upgraded from a 18 hp briggs to a 25 hp liquid cooled kawasaki. Back up sawing the next day. that's on a 95 lt40 manual. Some things to consider..
WEIGHT...The head lift mechanism on your old mill won't tolerate adding much weight. I added a couple of garage door springs to help.

The crankshaft pulley probably won't fit. You probably can get away with going 1/2 inch larger.
If the new engine crank is not the same height above the baseplate, the belt guards won't fit right. Don't leave them off, they more than safety gadgets. They must hold the drive belts in an oval shape when de-clutched. Otherwise you will wear out drive belts in a hurry. Does your old engine use a double drive belt ? If not, you will need to change that. 25 hp is a bit much for a single belt. New engine have a fuel pump? If not use a 3psi automotive electric pump. Ignition switch may have to be re-wired or replaced. Older engines grounded the ignition line to shut down, newer ones apply 12 volts to an ignition module to run. I had to do a little re-routing of the exhaust system. The muffler outlet pointed right at the plastic fuel tank. Throttle and choke cables will most likely have to be re-engineered.
Lest I sound like it's a lot of trouble, definetly worth it. Go for it. You ain't too old til you see the grim reaper coming. ;D

Oh, here's the end result..

sawdust joe · May 30, 2014, 09:04:35 PM

Pineywoods If at all possible run a deadended safty cable through the garagedoor springs so as when it breaks it wont hit you in the teeth :
nice looking job good engineering.
happy sawing be safe.

pineywoods · May 30, 2014, 09:19:47 PM

Quote from: sawdust joe on May 30, 2014, 09:04:35 PM
Pineywoods If at all possible run a deadended safty cable through the garagedoor springs so as when it breaks it wont hit you in the teeth :
nice looking job good engineering.
happy sawing be safe.

They say great minds run on the same track. The spring assist has been upgraded since the pics were made. There's now 3 springs, a double pulley and a safety cable. works good.

Chuck White · May 30, 2014, 10:36:54 PM

Here's some pics of the Pineywoods lift-assist we put in my mill a year ago!

https://forestryforum.com/board/index.php/topic,27272.msg985369.html#msg985369

Since then, I've retired the Pineywoods life-assist and installed a larger lift motor and heavier gear box, so the lift-assist hangs on the wall in my garage!

Once in a while someone will come in and say what's that?

I usually say something I made for my mill at the suggestion of a friend, thanks again Piney!

Auminer · May 31, 2014, 02:27:34 AM

Many Thanks for all the info! Pineywoods, I checked the weights of both and the darned Kohler weights ~118 lbs and the Honda comes in at 98 lbs, so no problems there.

QuoteThe crankshaft pulley probably won't fit. You probably can get away with going 1/2 inch larger.
If the new engine crank is not the same height above the baseplate, the belt guards won't fit right. Don't leave them off, they more than safety gadgets. They must hold the drive belts in an oval shape when de-clutched. Otherwise you will wear out drive belts in a hurry. Does your old engine use a double drive belt ? If not, you will need to change that. 25 hp is a bit much for a single belt. New engine have a fuel pump? If not use a 3psi automotive electric pump. Ignition switch may have to be re-wired or replaced. Older engines grounded the ignition line to shut down, newer ones apply 12 volts to an ignition module to run. I had to do a little re-routing of the exhaust system. The muffler outlet pointed right at the plastic fuel tank. Throttle and choke cables will most likely have to be re-engineered.
Lest I sound like it's a lot of trouble, definetly worth it. Go for it. You ain't too old til you see the grim reaper coming. ;D

Probably won't help much for out running the reaper, but had a new hip put in sure can't hurt. ;)
Didn't know 'bout the belt guards holding the shape. Yup, double drive belt, gotta check the pump, no problems either way. Seems like a doable thing, I'm gonna go for it. Gotta be faster than my old 14 hp Kohler https://www.youtube.com/watch?v=OZOmsz2Tx04 yep, that's mine...
Thanks again,
Dave

Gary_C · May 31, 2014, 03:16:44 AM

The other thing you should take a close look at is how much will all this work pay off in faster sawing times. Your total sawing time also includes up-down and return time for the head. Plus you have to account for your ability to position the log and remove boards and waste.

So are you going to be happy with a small increase in just sawing time?

Auminer · May 31, 2014, 03:45:46 AM

QuoteSo are you going to be happy with a small increase in just sawing time?

The return time should improve as well as I'll be able to use a different pulley set, right? I'll need to remove boards and waste regardless of sawing time, what am I missing here? Have you seen the video? Could you live with it?
Thanks for the insight Carl, and I am not trying to bicker, maybe I'm missing something here?

Gary_C · May 31, 2014, 11:09:21 AM

During any one cut cycle, sawing time is a small part of the cycle. So if you make a small improvement in one small part of the cycle, will that be enough for the money you are spending?

When Woodmizer adds horsepower, they also make improvements in other things like head lift power and speed. Also they add hydraulics and head setworks to get more speed. All of that to get faster cycle times.

boscojmb · June 01, 2014, 07:43:34 AM

Hi Dave,
I watched the video. Unless you wheir intentionally sawing slow to give yourself time to film, "sawing" is 90% of your cycle time. I think you will see a huge improvement with the new engine.

Left Coast Chris · June 01, 2014, 02:20:09 PM

I used a 24 hp Honda twin on my LT30 clone. It has worked wonderfully and has never missed a lick in the last 6 years. I do mostly weekend sawing so it sits more than it saws but it has been very reliable.

ladylake · June 01, 2014, 02:40:22 PM

Quote from: boscojmb on June 01, 2014, 07:43:34 AM
Hi Dave,
I watched the video. Unless you wheir intentionally sawing slow to give yourself time to film, "sawing" is 90% of your cycle time. I think you will see a huge improvement with the new engine.

Have to agree, a underpowered mill takes way too much time to make a cut. Steve

Gary_C · June 01, 2014, 02:58:55 PM

I didn't see the video before, but after watching I have to say that is about the slowest I've seen for sawing time.

What is determining your feed speed? I didn't hear the engine working too hard and also I wonder about blade sharpness and belt tension. Are you sure you are maxing out sawing speed with that engine?

I know the newer engines have much better governors (and more horses) than your older engine, but you should be able to saw faster than what you show in that video.

Magicman · June 01, 2014, 03:40:18 PM

Quote from: Gary_C on June 01, 2014, 02:58:55 PMWhat is determining your feed speed? I didn't hear the engine working too hard and also I wonder about blade sharpness and belt tension. Are you sure you are maxing out sawing speed with that engine?

My thoughts were the same as Gary's. Sharp blade? I did not hear the engine laboring, but I did see a belt flopping like it was loose. There was no sawdust output and a strange sawdust powder buildup at the blade guide??

Barney II · June 01, 2014, 04:05:27 PM

His biggest problem is the rheostat as this regulates the speed of the saw head====backwards and more importantly forward. I have a 1985 lt30 and there isn't that much difference between the two machines. If the speed set forward is only so much on the rheostat that is as fast as it is going to go regardless of the size of the motor. He should have the rheostat fixed. I have sent him a pm to this effect. It is only the better mills that have this luxury :D :D :D :D :D :D :D :D Don

Delawhere Jack · June 01, 2014, 04:43:15 PM

Have to agree with the others here, there are other issues besides lack of HP. I ran a 13HP manual mill for several months and it would have gotten through that cant in about 1/4 the time. The really fine, powdery sawdust tells me the band is dull.

Welcome to the FF.

trapper · June 01, 2014, 06:03:26 PM

My LT30 has a triple pully in the drive to give 3 different speed ranges with the same reostat and drive motor.

jmouton · June 01, 2014, 10:24:07 PM

we are replacing our 13 honda for a 24 honda on our lt-25 ,, havent put it on yet , but we did the pinnywood mod with the garage door spring , i think we will have to upgrade the spring size but other than that , the hp diff will be great, been wanting to cut a little faster and more efficient for a while now , cant wait to try it out

jim

Auminer · June 02, 2014, 02:16:15 AM

Sincere Thanks for those that watched the vid and gave constructive input! As Don pointed out my LT-30 has a rheostat and it doesn't work, never has. My first step is to put it back together (the fuel tank rusted out) and fire it up. Then take a look at the rheostat to get it working or at least to temp. jump over the contacts. Wow, I didn't really want to $pend for a new Honda, but it sure would be nice. First things first...
Then as Trapper stated:

QuoteMy LT30 has a triple pully in the drive to give 3 different speed ranges with the same reostat and drive motor.

I'll try different settings with the pullys, between the rhoestat working and the triple pully combination I should find a workable speed for this 14 hp.

QuoteIt is only the better mills that have this luxury :D :D :D :D :D :D :D :D Don

Gee, I always though my only class was "low". :D

Dave

Magicman · June 02, 2014, 08:38:49 AM

You added some serious information in your last post. I would have everything working correctly and as manufactured before changing the engine or making any modifications.

redprospector · June 02, 2014, 11:19:15 AM

The first mill I had was an LT-30 of about the same vintage. There was a lot of learning went on with that little mill. But they are very good mills, especially for the size timber I saw in the video.
My advise (and that's all it is, so you can take it or leave it) is to #1 get control of your feed rate. The rheostat has got to be replaced, period.
#2 The belt in the step pulley appears to be in the lowest geared position. You could speed up the feed rate by moving the belt, but you still won't have any "fine tuning" of the feed rate without the rheostat.
#3 It looks like you need to get the tension right on your blade drive belts (or they may need to be replaced). This will become very evident when you get an acceptable rate of feed.
Now, as for increasing the horse power.
I changed out the engine on mine, but I just went to an 18 hp. engine. I can't remember all of the specifics on the LT-30 since I haven't seen it in over 15 years. But you may want to take a look at your drive wheel shaft size before going to a 24 or 25 hp. engine. I think things were sized for the power provided from the factory.
I once knew a guy that put a built up 327 Chevy engine in a little Chevy Luv pickup.

All of the "weak links" showed up real quick in that little truck. They weren't particularly "weak links" with the 4 cylinder engine it was designed for, but when you up the anty you've got to be willing to dig deep. It's not always as simple as unbolting one, and bolting in another.