20 hp 42 in. Deck Lawn Tractor – CA Model

Experienced gardeners share their insights in answering this question :
Nearly any single or twin cylinder engine with the same configuration (ie. vertical shaft) will fit under the hood of a craftsman that used to run 20 HP.

How to Identify and Fix Common Gardening Problems ?

We provide a variety of viewpoints on how to identify and fix common gardening problems. Our sources include academic articles, blog posts, and personal essays from experienced gardeners :

All lawnmower engines are interchangeable. The engine mounting points are standard. So you can easily remove any engine and fit it to another deck.
While not necessarily universal, lawn mower decks are mostly interchangeable. Mower parts are usually built by the same company but sold under a different name, so lawn mower components, like the engine and the decks, can be replaced with a similar-sized model of a different brand with little to no problem.
Small riding mowers typically have single-cylinder, vertical-shaft, air-cooled gasoline engines. Lawn tractors and lawn and garden tractors may have vertical or horizontal shaft single-cylinder, air-cooled gasoline engines.
Lawn Tractor

Engine size range from 18-25 hp and most come with a single cylinder with step-up models having a V twin. Some fancier models also feature engines with electronic fuel injection.

An engine swap is a process of removing a car`s original engine and replacing it with another. This is usually done either because of failure or to install a different engine, usually one that is bigger and better to make your car more powerful and or economical.
It is possible to put a different engine on your lawn mower, although this is not something that should be attempted without proper knowledge and experience. The most important consideration is to ensure that the replacement engine is compatible with your existing mower.
Replacing the Mower Deck

Slide the deck under the machine and push it rearward to replace the belt on the engine pulley. Then move the deck forward until it`s in position to lift the back end and re-hang it on the rear support bracket.

A good starting point for a medium-sized yard – an acre to an acre and a half — is a 42” mower. With a larger mower, you`ll spend a lot of time maneuvering into position and around tight corners. For homeowners with one and a half to three acres to mow, a mower with a cutting deck between 42” to 48” is a good size.
Look for a mower with at least 14-16 hp and a wide mowing deck – at least 38 inches – to get your lawn work done quickly. Yards larger than three acres are best handled by a larger zero-turn rider or a garden tractor. Look for models that have at least 18hp engines and mowing decks in the 44-54 inch range.
Which Types of Engines are Used in Tractors? Most of the tractors are fitted with Diesel Engines with Direct Injection systems. These engines are categorised based on horsepower generated from them. Nowadays, engines from 12 Hp to 120 Hp are available.
Make sure you get the right tractor for your lawn size. 1/2 – 1 acre — For a lawn this size, you`ll want a riding lawn mower with a cutting width of up to 42″ and at least a 14 HP engine. 1 – 2 acres — For yards in this size range, a riding lawn mower with a 42″ or 46″ deck and an engine in the 14 – 16 HP is necessary.
Small-Scale Farming, Row Cropping, Plowing. We recommend tractors ranging from 51-65 engine hp for heavier-duty tasks on your property. Check out the John Deere 4052R and 4066R. If you run a small farm, these compact tractors are great when a utility tractor is too large or more powerful than you need.
Check the length of the engine and the transmission assembly together. Make sure that the assembly is the same length. It may be okay if it`s a few inches shorter or longer, however, it cannot exceed 3 inches or the assembly will not fit. There has to be room for the engine to move around.
Changing a car engine is one of the more difficult tasks a home mechanic may ever face. Replacing the engine requires different approaches for every year, make and model, so it`s important to utilize a service manual specific to your vehicle when taking on such a big project.
Fanbelts, timing belt, coolant hoses, radiator, waterpump, filters, spark plugs are items I would normally recommend if they had not been recently replaced. Other things that may require replacement on inspection are engine mounts, clutch assembly, spigot bearing etc.
If the equipment the engine powers is old, it may make sense just to buy a new lawn mower, log splitter, or whatever machine is in question rather than spend money diagnosing and fixing its engine. If it`s a newer piece of equipment, it could be worth repairing or replacing the engine, depending on the diagnosis.
Changing the Spark Plug and Air Filter are good ideas, and are general maintenance items. The carb cleaner could also be sprayed into the carb through the intake. If those items dont restore power, there is a good chance your motor`s compression is low – and you need to rebuild it.

Discover Relevant Questions and Answers for Your Specific Issue

the most relevant questions and answers related to your specific issue

I have had a poulan pro 550 series push mower for almost 1 year at the end of the season last year the mower would start briefly and then stop. i have cleaned out the air filter and that did not help.the mower started, i made one revolution around the yard 3/4th of the way the mower quit. I then primed the mower it started then quit and now it will not start at all. Does anyone have any suggestions of what to do. Thanks
ANSWER : There is a little spring that works the carburetor arm. If that popped off then the mower will not run.

Lawn mower cranck but wont start…
ANSWER : Since you already checked for spark and air I would drain all the fuel out of it and check that fuel for water. Over time some lawn mowers end up with contaminated fuel. You can see the water sitting on the bottom of the fuel if you let it stand for a bit in a small plastic bowl.

Be sure to empty and dry out you fuel can as well. Especially if the mower stopped running right after a refuel. Which is a good sign your gas can is contaminated too.

We had a Poulan lawn mower with a Briggs & Stratton engine last year that started with the engine revving problem. The RPMs would go up and down and the fumes coming out of the mower near about killed me. So this year we purchased a brand new Poulan Push Mower – model 961120083. Just brought it home on Saturday – last night we used it for the first time – guess what – the engine revs up and down just like the old one. Almost to the point of stalling and again the fumes are bad. It can’t be a dirty mower it’s brand new. What’s up with their mowers?
ANSWER : There seems to be one common source for gas for the 2 mowers. You could be placing old or contaminated gas in the NEW and OLD mowers. The fumes comment you made leads me to think that the problem is with the fuel itself. Old gas smell horrible. Sniff test the gs can you use for filling the mowers. If it smells awful you know you need to get rid of the contents of the can rinse it and then re-fill it. There may even be water in the gas can that went straight into your new mower. IF you drain the gas from your mower and gas can and start anew and the problem persists then you should immediately seek warranty service for you new mower.

With the 2 mowers having different engines and the same problem it just points to the gas supply as the source of the problem.

Thanks for using Fixya.


Wont start no ignition put new plug in and fuel filter
ANSWER : Flush gas tank, fill with fresh gas and Stabil. Replace air filter. Remove bowl from carb clean bowl and holes in bowl screw.

My Honda 160cc lawn mower engine cut out when I hit a large clump of grass. Now I cannot get it to start. Has always started with no problems. What to do?
ANSWER : Has probably broken flywheel key ….. putting it out of time

I have a Poulan push mower that after mowing in a ditch started making a loud noise and running rough. It almost sounded as if metal was hitting metal. The mower was vibrating more than normal. I checked under the mower and nothing is hitting. After a few times of stopping the mower engine because it sound as if it is going to die down the mower will not start now. The shaft does not appear bent and the blade appears ok. The mower has oil, a good spark plug and a clean air filter. It was running fine until that moment. I did not see anything that I hit but it is possible I hit something in the ditch like a pine cone or branch. What could the problem be and how would I go about fixing it?
ANSWER : If you are sure the oil level is correct then it sounds like it’s about to die, unfortunately. A pine cone shouldn’t cause any damage, but a large branch may do so. Was it smoking before you shut it down? The vibration could be caused from a bent blade. It could also be caused from a part breaking in the motor. I wish I could have given you better news!

Good Luck,


My Toro mower with a Briggs & Stratton engine starts and then cuts off after a few seconds. How do I fix this?
ANSWER : If it starts on choke and then stops may need to clean out carby and fuel tank

Where is oil drain plug on MTD mower – Mtd LAWN MOWER PART # 683-04163B FRAME Assembly:RIDER
ANSWER : If it isn’t on the bottom of the engine (above the blade) then you don’t have one. This is not that uncommon. When you need to drain the oil, FIRST- pull the spark plug wire off!!! Then remove the dip stick or filler plug and turn the unit upside down and drain the oil.