HOW-TO Replace A Lawnmower Crankshaft Seal

Crank Seal used is B&S part #391483s

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45 thoughts on “HOW-TO Replace A Lawnmower Crankshaft Seal

  1. Donny ,what should be the part # for the same ring , bit for a Craftsman mower with a front wheel drive assist? Thanks I've had to add oil every time I mow. shes burning up to, so I gotta change it an put maybe some Lucas oil in , at 1/3rd to its regular oil specs . I want it a little thicker to help it stay cool do you think that will help . Thanks donyboy, hope the wife is doing well this winter but it almost over lol .!!

  2. if only i had watched this 5 minutes earlier, i wouldn't have to chase all over town looking for a second new seal after screwing up one.

  3. Thank you….so few videos are as informative as yours in short time. I have a background in most of this just not that seal. Kudos my friend.

  4. Very helpful video, I had to replace crankshaft seal in a Tecumseh Lev195ea. I did not have aviation gasket maker so I used high temperature Red RTV by permatex.
    I will update with the results in 1-2 days

  5. Cool…….I always assumed it was an engine strip down to replace the seal.
    Anyone know the seal part number for a B&S 375 engine?

  6. Would a bad crank seal cause oil to get in air filter ? I have a pressure washer that leaks oil somewhere and I noticed some oil in air filter.

  7. I'm trying to do this for a self-propelled mower. The drive pulley seems to be firmly seized to the shaft. I built a puller to fit snuggly around the shaft and pulley. I've applied heat and penetrating oil, and it is still stuck. Any tips for removing it without destroying it?

  8. I recently replaced my cam shaft and now a small leak from the crankshaft appears ! I was about to take the engine apart until I seen your video ! Cool one ! 🍾

  9. Dony, another great video. Thank you. Can you tell me what brand of bearing/pulley puller you use? It seems more hefty than most I see on the market. Also, for small engine repair, what size depth of puller would be a minimum for you? I'm considering buying a Posi-loc puller because they seem much more robust than others on the market, but the five inch depth one goes for $125USD and it's a three jaw puller, not two. Any advice would be greatly appreciated.

  10. Heya donyboy…I got an issue with a mower I got. It runs fine when starting up. But when it gets "hot" it starts to surge. I cleaned the carb several times. Made sure all the gaskets are good. The spark plug is also good as well as the air filter. Beyond this what are the usual suspects? thx.

  11. I need serious help anybody I have a poulan pro ppbp30 I have just bought a new carb put fresh gas new spark plug and I still won't start I only got it to run once and it died right after I adjusted the choke. I am pretty sure it's not the fuel filter. I know it's getting spark and fuel. I looked every where for a piston and cylinder kit. If anybody can help i would be very appreciative.

  12. OUTSTANDING video, I would have thought the motor would have to be removed and the crank cover removed but thats not the case which is awesome news:-)

  13. I ran over a piece of metal in my yard with my push mower and it killed the engine. Then when I restart the mower it starts fine but after it warms up it starts leaking oil onto the top of the deck and smokes really badly. Any idea what might be causing this?

  14. Hey dony boy i got a question i have a troy bilt pressure washer is a 3000 psi it needs a pump,do you think is going be ok if i install 2700 psi pump on it ?

  15. WARNING to anyone interested regarding CAR REPAIR MANUALS: don't ever buy a repair manual from " eManuals" located in the U.K. they will take your money and you will receive a corrupt download, that will not load and harm your computer.
    This is a public service to warn others, I got burned from these people and I'm trying to help others from the same.

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