I can give you some input based upon my experience with the engine (16 hp Kohler single) and tranny (K51) that is in my 2000 Scotts 1642. These are the same engines and transmissions used in the LT155 and LT160s that year. I have approx. 300 hours on my tractor. The enging and tranny have been flawless. My tractor has a 42" deck, but again, comparing it to the 42" deck available on the LT155 and LT160 that year, they are nearly identical. My unit has not lead a particularly easy life. I pull a 40" Brinly core aerator around behind it with 125 lbs of extra weight twice a year. I mow approx 3/4 of an acre with some hills. If the tranny and engine on the LT150 feel strong I wouldn't worry about them failing or being the weak points in those tractors. BUT, without knowing the hours or how they were used (or abused) by the previous owners, I would buy the new one. You get a warranty and from the description of how you plan to use it, it should last for the rest of your life. The Deere LT's were good machines. I wanted one but they were about a $1000 more than the Scotts units at the time and I couldn't afford the jump. It turns out these early JD Scotts units were pretty good machines and based on how it has performed up to this point, I would expect another 7 years out of it without any major problems. Good luck in your decision.

You speak of the engine. The kohler Courage is fairly new (the older, heavy duty kohler was a command) The Briggs extended life engine seems to be the same V-twin that they have had for years, but with a better air filter mounting, and perhaps other filters updated, also. Then you mention being on a hill. and pulling some attachment. This suggests a stronger tranny to be in order (though some have done OK with a minimal tranny). By the time you get to a garden tractor, the tranny should be plenty for what you want. It seems most of the trannys have been made by tuff torq or hydrogear (with tuff torq being used the most lately). The lightest duty tufftorq is the K46, with various numbers up to a K91 (this is a real brute, in JD x700, I think). I bought a murray with a K66 tufftorq and am quite pleased with it. I also have a craftsman with a hydrogear -3500 which has plenty of pull, but is controlled by a lever on the fender (which is fine after a spinner is added to the steering wheel). I have heard of some sales on craftsmans with the K66 close to your price, but Simplicity and JD prices are way above your price with this tranny. And you may feel either is worth it based on the many other features. JerryO

I have had the same problem with the 8500 series horizontsal 6 hp. First engine I lost because of it, but Briggs sent me a replacement which is also leaking and 2 bottom bolts are gone. Good luck finding new bolts. They a 7mm fine thread which is very very uncomon. Being a mechanic, I deal with industrial fastener companies and none in St Louis area had it. I had to get them from Briggs. Why can't briggs use locktite on them. I know it costs an extra 2 cents. My opinion is briggs are cheap junk. Look at your air filter housing and how the blow by hose is just stuck in a hole in a piece of cheap tin. The hose comes in on the back side of the filer and fits like s**t. THE engine sucks alot of dirt around it ,and some times it falls out sucking in more dirt than you can imagine.

Walt, thank you so much for taking the time to think this through and write about it in detail. I drove to Springfield today in hopes of talking to a mechanic at a huge power equiment business there that is well known for parts and service...unfortunately it has closed and there is no "we've moved to..." sign. This economy is killing everyone. Oh well...sleuthing with you all, I guess! :) Anyhow, to answer some of your comments, I have run two tanks with SeaFoam but seen no improvement since using it. I have a stupid qustion regarding the ground for the battery...I only see the two main battery cables (pos. and neg.) and then they lead underneath the battery compartment/seat area to places unknown and impossible to see or get to without removing the entire metal cover for the mower. I've had experience dealing with battery problems on my pick up truck and I know there was a separate ground wire that was attached with the negative cable for my truck but I don't see a separate ground for this machine. Is it bundled with the negative cable? When I removed the battery from it's compartment, I still can't see where the cables lead (although I saw a white plastic flywheel of some sort under the battery area, what the heck is that?? Just curious!) Is there any way to get to any of this stuff without removing the mowers metal cover? I was going to remove the starter and take it to a mechanic to test it but couldn't figure out how to get it off the motor. I asked a neighbor who rolled his eyes and said "It's only 3 bolts!" but when he looked at it, he couldn't figure out how to get it off there either (made me feel better...the little eye-roller!) Regarding your comment: IF you have a GOOD set of jumper cables, jump directly from the batter to the starter as you said you did with the charger and see what happens. The contacts of the starter solenoid that you hear clicking may be burned until they do not conduct enough current anymore. By passing as above may help tell if this is a problem but would need more checking. I have a good set of automobile jumper cables..I can definitely try this and see what happens. I'll continue to post if I have any luck with this. I think it might be time to junk it and get something new but I really, really hate doing that. I'd rather fix it if it's possible and cost-effective. It's a shame that this engine has a history of this problem yet Briggs&Stratton never dealt with or addressed it. Oh one last thing, would a bigger/stronger battery help in any way or not since you said the starter is maxed out when conditions are ideal? Thanks again!