Engine information on popular Craftsman Models

Craftsman 5018H

Original Model: Kohler M18
The original engine on this was Kohler 18hp Magnum M18, which has been discontinued. There is nothing like this engine currently produced.

Craftsman DGT4000

This engine has a 1-1/8"x4-3/8" shaft on it. The CV740-0005 was discontinued in 2010. You can use another Command Twin with an 1-1/8" x 4-3/8" shaft and switch over some external parts from you engine if needed.

Craftsman DGT6000

Original Model: Kohler Command 25HP CV730S or CV740S-0018 or CV740-0024 This engine has a 1-1/8" x 4-3/8" shaft.

Craftsman DLS3500
Original Model: Briggs Intek Single 20hp 31P777-0635 E1 
1"x 3-5/32" Shaft, Gravity Fuel Feed, 5/3 Amp Alternator
You will need to reuse your muffler from your original engine. You may have to make slight wiring adaptions as the plug may not be the same.
Craftsman DLS4500
Original Model: Briggs Intek Twin 24hp 445677-0827 E1
1"x 3 - 5/32" Shaft, 5/3 Amp Alternator, Fuel Pump
You will need to reuse your muffler from your original engine. You may have to make slight wiring adaptions as the plug may not be the same.
Craftsman DYT4000 Category
Original Model: Various Brands
NOTE: You cannot interchange engine brands or series without major work. These tractors were made with different engines. 
If you have an electric clutch you will have to purchase an engine with a 9 amp or larger alternator or reuse the stater and regulator off of your old engine.

Briggs Intek Single cylinder engine 31P777  & 31P977-1066-E1 (917.273630)
If your engine has a fuel pump, you will need to purchase and engine with a fuel pump or reuse you dipstick tube, fuel pump, all vacuum and fuel lines, and fuel pump bracket.

Briggs Intek Twin 445777 407777-0121 with a 1" shaft. 

Some also had a Kohler CV730-0018 which has a 1" x 3 5/32" shaft. 
You cannot interchange the Briggs and the Kohler engines, they are totally different. 
You can use a Command Twin, there may be minor differences however parts would be interchangeable if needed.
Craftsman FS5500
Original Model: Kohler CV730S-0040
This engine has a 1" x 3 5/32" shaft and was discontinued in 2012. 
Craftsman GT3000
Original Model: Kohler Command CV675S-75544 or CV20-65577
1-1/8"x 4-3/8" Shaft.
Craftsman GT5000
Original Model: Kohler CV730-0017
The CV730-0017 and the CV730S-0044 engines have a 1-1/8"x 4-3/8" Shaft on them. 
Craftsman GT5000-Briggs
Original Model: Briggs 446977-0471 & 40H777-0241-E1
Both engines feature a 1-1/8"x 4-3/8" Shaft.
Craftsman GT6000
Original Model: Kohler 20hp MV20-57529
The Kohler Magnum Engine series has been discontinued. No other engine produced replaces it.
Craftsman GT6000-Briggs
Original Model: Briggs 446777-0244
This engine has a 1-1/8" x 4-3/8" Shaft. 
If you have an electric clutch you will have to purchase an engine with at least a 9 Amp alternator or use the Stator and Regulator off of your old engine. 
If you have a fuel pump on your current engine, you will need to purchase an engine with a fuel pump.
Craftsman GTV16
Original Model: Briggs Opposed Twin 401417-0166
This series of engine is no longer available.
Craftsman LT1000
Original Model: Various
Briggs Intek Singles: 310707-0137, 311707-0132, 31C707-0230, 31H777-0297, 31H777-0605, 18hp 1"x3-5/32" Shaft, Electric Start, 5/3 Amp Alternator
Briggs Opposed Twin: 461707
One of the engines used in this tractor was a Briggs 310707-0137, another was a Briggs 31C707-0230. 
Some of the older tractors had a 20hp 461707 Briggs Opposed Twin engine in them.
If you have an electric clutch you will have to use the alternator and regulator off of your old engine unless you purchase an engine with a 9 amp alternator or larger. If you have a fuel tank or fuel pump mounted to your engine you will also have to use it off of your old engine If you have room for an engine with an oil filter you could use the engines listed with the filter.
Craftsman LTX1000
Original Model: Briggs Intek 407777-0121
21.5HP V-Twin with a 1" x 3 5/32" shaft.
Craftsman LT2000
Original Model: Various Brands
You must stay with the same brand and model design as what is currently on your tractor, you cannot switch without major problems.

Kohler Command Single CV490S-27508 & CV492S-27506 
Kohler Courage SV490-0004 
Briggs Intek Single 31P777-0299, 31P777-0371, & 31P977-0575
These engines have a 1”x3-5/32” shaft on them. 

Note: If you have a Briggs engine and you have an electric clutch you will have to use the alternator and regulator off of your old engine or buy an engine with a 9 amp alternator or larger. 
If you have a Kohler engine with a fuel pump, you will have to purchase an engine with a fuel pump. If you have a Briggs Intek with a fuel pump on your engine you will need to buy an engine with a fuel pump or use the fuel pump off of your engine.
Craftsman PL1000
Original Model: Briggs 310707-0137
Craftsman YS4500
Original Model: Various 1" x 3-5/32" shaft
Briggs 31P977-0670-E1, 331877-0805, and 331777-0956 
Kohler Courage SV600-0025 
NOTE: You cannot interchange engine brands, you will have to replace your engine with the same brand and model series.
You will need to check your mower to see if you need a Fuel Pump or large (9 Amp) alternator to run the Electric Clutch.
Craftsman YT4500
Original Model: Briggs Intek Twin 26hp 445877-1565 E1
1"x3-5/32" Shaft, 16 Amp Alternator, Fuel Pump
You will need to reuse your muffler from your original engine. You may have to make slight wiring adaptions as the plug may not be the same.
Craftsman ZT7000
Original Model: Kohler Command CV492S-27531 and SV600-0010
These engines came with a 1" x 3-5/32" shaft and a fuel pump. 
NOTE: YOU CANNOT INTERCHANGE THE CV SERIES WITH THE SV SERIES. THE EXHAUST IS TOTALLY DIFFERENT.
If you have a fuel pump on your old engine, you must purchase an engine with a fuel pump on it.
The CV492S-27531 and all Command Vertical Singles have been discontinued by Kohler and are no longer available.
Craftsman ZTS7500
Original Model: Briggs 31M977-0111-E1
20hp Vertical 1" x 3 5/32" Shaft, Fuel Pump, Electric Start, 9 Amp Alternator.
Craftsman LT1750
Original Model: Kohler Command CV491-27501
These engines came with a 1" x 3-5/32" shaft and a fuel pump. 
NOTE: YOU CANNOT INTERCHANGE THE CV SERIES WITH ANY OTHER ENGINE SERIES. THE EXHAUST IS TOTALLY DIFFERENT.
If you have a fuel pump on your old engine, you must purchase an engine with a fuel pump on it.
The CV491-27501 and all Command Vertical Singles have been discontinued by Kohler and are no longer available.