7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000

PNWguy

Member
Joined
Aug 13, 2023
Threads
1
Messages
16
  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
I bought a used craftsman riding mower for a few hundred dollars thinking that I could fix it. I was told it sat over winter and they couldn’t get it started this year. They said they didn’t know much about fixing it so they bought a new one. I figured it sounded like maybe a easy fix. Guessed wrong so far. They replaced the battery but with low torque I noticed. When I got it the battery was dead. Charged the battery, adjusted the Values to 005, both intake and exhaust. I tried to start the engine, a few times the engine didn’t want to turn over more then an inch. I rotate the engine by hand over the high compression and I tried starting the engine. The engine started right up and ran really good. Cool I thought!
, that I have fixed it. Wrong. When I tried to re started the engine, the same thing again. I replaced the started thinking it was bad or going bad. I replaced my starter. I still had the same trouble starting the engine, not turning over enough to start and now I broke two starter gears.

Q, I am not if the started is installed correctly, Is there supposed to be a shim/washer under the rear starter bolt Between the engine and the starter? When I was removing the starter a washer fell and not sure was it behind the starter or not? Currently there isn’t one and I have broke two gears now. Maybe that is my answer. Or is the high compression breaking my starter gears?

Q, I can’t tell if the crank/cam compression release lobe is releasing on my mower looking at the valves. The little bump what I have read and seen on the you tube videos. I have read an old 2014 forum had a similar problem but they replaced the starter and they were good. Or so good for me. I may have to take it down to the repair store if I can’t figure this one out.

Any help would be great

Stan
 

ILENGINE

Lawn Royalty
Joined
May 6, 2010
Threads
43
Messages
10,732
  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
If you are sure the valve clearances are correct, and may want to double check to confirm. then next step would be the camshaft due to a broken compression release. And the washer would of been on the outside not behind for a shim. If it even was supposed to be there, unless that washer came from someplace else.
 

Craftsman Garage

Well-Known Member
Joined
May 2, 2021
Threads
34
Messages
473
  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
yeah, ive had my fair share of mowers with a bad acr (like half of them) and sometimes if its not too bad you can buy a very powerful high cc batter for them and it sorta bypasses it, but yeah, when looking for a mower, avoid the 21xxxx, 28xxxx, 31xxxx, and 33xxxx briggs and stratton single cylinder engines, especially the intek ones
 

bertsmobile1

Lawn Royalty
Joined
Nov 29, 2014
Threads
65
Messages
24,995
  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
Check you got the correct starter, there are several of them and there is 2 different size of drive pinion.
On top of this all of the cheap imported starters are 2 pole ( 2 magnet ) starters that consume a massive amount of Amps for very little torque .
Most of them fail within a couple of years
The brushes are very soft and many will have so much carbon dust accumulating that they short out .
 

Craftsman Garage

Well-Known Member
Joined
May 2, 2021
Threads
34
Messages
473
  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
i forgot that i have this exact same mower! if you have any questions, ask me because i now have a visual of what you r dealing with lol
 

PNWguy

Member
Joined
Aug 13, 2023
Threads
1
Messages
16
  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
If you are sure the valve clearances are correct, and may want to double check to confirm. then next step would be the camshaft due to a broken compression release. And the washer would of been on the outside not behind for a shim. If it even was supposed to be there, unless that washer came from someplace else.
Thanks, I will double check my clearance again to see if there the same. Could the engine still run if the compression release was bad? I had the engine running a few times and even mowed the lawn with it one time until the starter broke today. Thanks for the washer note.
 

Craftsman Garage

Well-Known Member
Joined
May 2, 2021
Threads
34
Messages
473
  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
Thanks, I will double check my clearance again to see if there the same. Could the engine still run if the compression release was bad? I had the engine running a few times and even mowed the lawn with it one time until the starter broke today. Thanks for the washer note.
yes it can, you can put in a new and much stronger battery and that will essentially bypass the ACR or i have seen some people cover up the intake hole with their hand and it would start, just some advice from someone who had 5 or 6 of these Hard-to-crank blown acr engines, just sayin
 

PNWguy

Member
Joined
Aug 13, 2023
Threads
1
Messages
16
  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
Check you got the correct starter, there are several of them and there is 2 different size of drive pinion.
On top of this all of the cheap imported starters are 2 pole ( 2 magnet ) starters that consume a massive amount of Amps for very little torque .
Most of them fail within a couple of years
The brushes are very soft and many will have so much carbon dust accumulating that they short out .
I took my old starter into a local Electric shop, they told me that they only make one style of starter for my mower, however there are three qualities cheap , middle of the road and the best. The starter that I got they just happen to have a new one on the shelf. The gear only lasted about a dozen starts then broke. I had the old starter and they swapped out the gears for me. Unfortunately my old start gear broke only after a few attempts trying to starting my mower. I will have to do some more research on the different size drive pinions. Thank you
 

Craftsman Garage

Well-Known Member
Joined
May 2, 2021
Threads
34
Messages
473
  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
I took my old starter into a local Electric shop, they told me that they only make one style of starter for my mower, however there are three qualities cheap , middle of the road and the best. The starter that I got they just happen to have a new one on the shelf. The gear only lasted about a dozen starts then broke. I had the old starter and they swapped out the gears for me. Unfortunately my old start gear broke only after a few attempts trying to starting my mower. I will have to do some more research on the different size drive pinions. Thank you
i think they make metal ones...
 

Craftsman Garage

Well-Known Member
Joined
May 2, 2021
Threads
34
Messages
473
  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
did some cross referencing...

 
Top