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

TobyU

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  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
Most likely valve clearances. The compression release can break, but I would definitely check the valves first. If it is the compression release, make sure you get a new cam seal - they are a booger to get to seal again!
What the heck is a cam seal?

In doing a camshaft replacement, the seals you may need would be the engine sump bottom gasket or possibly a valve cover gasket or two depending on whether we're doing a single or a twin but this post was about a twin.

There are no seals for the camshaft as it simply sits into the machine hole on the top and the bottom.

The valve cover gaskets on the Briggs are far better if they are the older style that is a paper gasket because you can almost always reuse those and they rarely leak.
They got cheap a few years back and started just putting our TV on them which works fine also and again they rarely leak

The only time they actually leak is when people don't wipe the dad or get something stuck on them or just over tighten the bolts excessively.

Now the Kohler on the other hand for the courage single is a completely different animal and that thing hardly ever seals properly or completely..
 

jviews12

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  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
If you can turn it over easily with plugs out and a wrench, then try starter. It will not start but tel you you did the valves backwards. Could be valve rods are bent or something. Yes, try with plugs out so no compression.
 

charleneje

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  • / 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
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
I own one of those YT3000 mowers I bought new in 2014 had nothing but trouble with it right now its parked needing a transaxle. But I had similar problem to you with it not turning over and found that the fuel had been running into the crankcase how I don't know. when you did actually start it was there any smoke. I would definately check the oil level and find out if it isnt that the fuel hasnt built up ontop of the piston that will stop the engine turning over have you pulled the plug out and tried to spin it on the starter and if so was any liquid blown out of the plug hole. I do suggest that once you do get this mower running you put a shut off valve in the fuel tube to the carb.
 

MowerNick

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  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
The intake push rod is aluminum and the exhaust is steel. it does make a difference so take note when reassembling
 

PNWguy

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  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
I would like to thank everyone that posted and gave me advice. My ACR on the cam was broken in several pieces. I replaced the cam assembly and my starter gear, adjusting the valves, put a new spark plug in, gas filter. After getting it all put back together and installed back on the riding lawnmower.. My engine started right up and ran so smoothly. Back on the lawn again.
 

bertsmobile1

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  • / 7 year old Craftsman 21 hp riding mower hard to turnover & start, High compression stroke. Model 331877 2371 G5, YT3000
:giggle: (y)
 
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