Csme across an engine rebuild of a Sportsman 850 engine. Excellent video. This is something that I could do, for a living too.

A question on when he puts the main bearings in the lower case, he uses a dab of grease to hold them in. The bearings won't spin because of the grease?

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Part 2


Part 3


Part 4


Part 5

 

Looks good projects and tutorials, gonna watch the rest at home.

 

Good video only he didn't check for valve leakage with solvent. If a head had to come off I always used a fine wire brush on my angle air grinder to remove the carbon build up and then checked for leakage. If any seeped,all the valves would be pulled,carbon removed from the stem and under side of the valve. Then a light lapping with fine lapping compound. Replace the valve guide seals and reinstall the valves.Then recheck for any seepage. As far as grease on the plain bearings,yes this is to make sure they stay in place even though the tabs are suppose to lock them in.Better safe than sorry and have one fall out and not notice it. Tough to have to tear an engine apart the second time for something like this. These plain bearings don't turn,the crank journals spins around them.The grease would melt in a short time. If you loved working on engines it's rewarding to hear one you rebuilt run for the first time.That never got old for me. Did get a little old as the hands wore out and as the years rolled by though.

 

Thanks OPT. Working on atv is what i want to do after i retire.

 

A lot of old retired techs work to keep themselves busy and earn some good bucks while doing it. If your health is still ok,go for it.

 

My plan is to take ezrly retirement at 55, take the powersports tech course at a local college. Then head off in to the workforce.

I emailed the instructor, he said is people looking for a second career, freshly retired and some fresh out of highschool.


If i could do it sooner, I would.

 

Its nice to find a job you actually enjoy doing. I'm sure you won't have any trouble finding engines that will need rebuilt. With all these high performance engines out there now, I simply don't think they will last as long as many of the older designs. Squeezing extra power comes at the cost of long term durability. And I don't mean just for Polaris either. While Yamaha, Suzuki and Honda still have single cylinder engines that make modest power, the rest all have high compression v-twins that probably won't last 20 years like these engines do. Run them hard and in 10 years(or less as is in the case of this 850) many of them will need rebuilt.

 

Efi machines certainly wont last,unless they can make the harnesses,modules and sensors better and less sensitive to water and vibration. That's the main reason I don't envy the guys out there now since even the youth models are heading to efi also. Carb models are heading the same way as two strokes and getting to the point that you have dealer software to pin point problems that go past codes the displays show.I really believe in a few years all you can be able to do is change oil and filters and the plugs.

 

I have no intentions of getting rid of my 400HO. But Greg and I are of the same opinion on hp and longevity. My next atv could very well be a grizzly 700. Rock solid reliable.

 

The previous Grizzly 700 proved to be quite reliable. The new 708cc engine should be as well. A 50" Wolverine with that engine would be a great addition to Yamaha's lineup if they would simply build it. It would sell faster than they could build them. If I had a lot of money, I wouldn't care if a new quad only lasted a few years. I'd simply buy a new one every 3 or 4 years. I don't think the new quads are that unreliable but probably 10 years would be a stretch for many of them without major repairs. Probably the worst will be these new high hp turbo utvs. I give them about 5 years before either the engine or turbo need work. A lot of it will be the owner's fault though. People will buy them and drive them like they're in Nascar. Just because a machine can run 85 mph doesn't mean you should drive it that fast all the time. But they will pin the throttle because they can and the abuse will be hard on engines and drivetrain that are already stressed.