Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

Existing motor is a B&S 3.5HP Model 92905 Type 1825-01 Code 77083004.   I have tried the B&S site and could not find a correct replacement.

Any direction on how to research for a direct replacement engine would be greatly appreciated.  I have had the mower for 16 years, I bought it used

it has been a great mower but the engine is pooped.

Why would the replacement engine not fit the deck?

Friiy

friiy wrote:

Friiy

It is a self propelled, 21" aluminum deck.  You are correct about the lack of space for a modern engine.  Another problem is the fact that the spark plug on the old motor is indexed on the left hand side and the newer motors I believe have the spark plug facing forward.  There has to be a replacement engine that can be adapted to fit.  I just have no idea where to start looking or what has to be done to make a modern engine work on this mower.

friiy wrote:

As I remember it was just too big and there was no way to center the shaft in the mounting hole due to engine hitting discharge chute and or drive mechanism.  I have no idea what model or manufacturer Small Engine Warehouse gave me.

I have repowered my Snapper cast deck self propelled 21" twice since I bought it new in 1974. Both times I used Tecumseh power because I wanted 5HP as opposed to the anemic 31/2 horse Briggs it came with. The first engine was a TVS120 4 stroke which was a good dependable engine with lots of power and well worth the $125 I paid for it from a local mower shop.

About 3 years ago I bought a TVXL 840 from Small Engine Warehouse because I remembered a fellow named Tecumseman who posted on several of the sites saying it was the most powerful 5hp engine he ever used. It's a 2 stroke and is really unbelieveable. The old Snapper is my backup mower because it doesen't mulch very well. But as far as power is concerned it puts my 6.5hp Kawasaki powered Toro 22177 Proline to shame.

Both the TVS120 and the TVXL840 are direct bolt ins for the 31/2hp Briggs and fit the aluminum Snapper deck. Tecumseh also made a TVS840 which is the same as the TVXL 840 but has an aluminum  bore instead of cast iron. Maybe you can find one on the net.

Marc

mml4 wrote:

Marc:

Thank you very much for the information.  I was about to give up hope, but I thought I'd check back on this site to see if there were any more responses.  I hope these engines you mentioned are still available.  I'll start checking around, and thanks again!

Marc

I have not been able to find any of the engine model numbers you mentioned.  Are they still available from anyone other than Small Engine Warehouse?

JRD182

jrd182 wrote:

With Tecumseh just going under I'm not sure if you are going to be able to find one easily. I would check the net and the dealers on ebay.

Marc

mml4 wrote:

Marc, I was able to get a NOS TVXL 840 Tecumseh off of ebay.  The only problem I see is the throttle control  on the 840 is up front instead of on the left (plug) side like the "old Briggs", this puts the throttle cable in a bind trying to make an abrupt 90 degree turn.  Will a longer cable work or is there something special that is used for the abrupt 90 degree turn?  Thanks again for getting me this far.

John

John-Congratulations on finding the engine. The stock throtle  cable from the Briggs won't work. You are going to have to find an aftermarket with a cable(longer) you can work with or see if you can mount the original on the other side and lower on the handle bar.. Another issue is going to be  disabling of the blade brake and grounding wire of the brake system. Place the engine upside down on a towel and look for the blade brake return spring . It is attached to the brake control lever that has the brake pad attached to it. Remove the spring and cable tie the lever so that the pad is not rubbing on the shaft. You will also see a shorting clip that would cut the ignition when the spring pulled the lever to where the pad contacted the shaft. I wired the clip to one leg of a  momentary switch on the handlebar so I could short out the ignition in order to shut the engine off. Which way do you have the muffler facing? Notice you can rotate the engine to several positions. You must find the position that allows you to mount the bag so it doesent get burned by the exhaust and also leave the pull start available to be used. I am sure you already figured this out-

Good Luck,

Marc

PS- If you got the manual with your engine you will see it suggests TC-W11 or TC-W3. From what I know these are the outboard motor variety of 2 stroke oils which are formulated to be run in engines that don't turn the high # of rpm that  a blower or string trimmer do and run at cooler temperatures. The manual also suggests 50:1 mix with DOUBLE the ammount of oil in the first gallon (25:1) No explanation but I bet it has to do with the cast Iron bore.

mml4 wrote:
I have never had a mower with a blade brake.  I have looked for the brake control lever that has a brake pad attached.  Is this a brake pad that will contact the drive shaft and stop the blade from spinning?  If so I don't see it.  Do I have to remove something to access these items?  I am looking around the carburetor linkage area.  I have downloaded a Tecumseh technician's manual which covers TVXL840 and other modeles and on page 16 & 17 it has pictures of the Self-Energizing Brake system.  I see nothing "exposed" that looks anything like the pictures in this manual.  Is it possible this NOS model I bought does not have a blade brake? To answer your question I have the muffler facing the left side and this places the throttle controls towards the front, and engine  also clears the discharge chute with the fuel tank and pull cord on the right side. These are the numbers that are stamped into the blower housing TVXL840-8405A  7301A.