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Posted

Compression is good but it has no spark so I'm pretty sure that's going to be the direction to look. I'm a former auto mechanic and current industrial machine repairer so I'm pretty good at mechanical problems. I have narrowed it down to most likely the ignition pickup / stator which has a replacement on order

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  • 2 weeks later...
Posted

No start update, I found the cdi box was faulty causing no spark. I installed a new cdi box and we now have spark but still no start. I pulled the cam gear cover and timing plug and now I believe I have found the problem. With the flywheel set at the T mark for top dead center the cam gear mark is about 80 degrees off of the mark. Timing chain is snug so I'm pretty sure it hasn't jumped timing plus good compression points to that conclusion as well. I belive the flywheel key has sheared. I should have a puller coming tomorrow so I'm going to pull the flywheel and see what the key looks like 

Posted

Well finally some good news. Pulled the stator roter off and sure enough it had a sheared key, replaced the key and it started up. That brought to light another issue. It would start easy the just die for no reason, I suspected it may be the carburetor even though it's been replaced I did have to evict a mud dobber nest that had made a home in the fuel inlet because the fuel line was disconnected when I got it. Well I've been searching for other reasons why it would die suddenly, just about ready to dive into the carburetor when I decided to look into why the aftermarket led flood lights were dim. I found a bad or non existant ground between the engine and frame. I ran a new ground wire from battery negative to the frame the started it up and it sat and idled for a good 15 minutes and did not die. Now when the new drive belt comes in maybe I can actually test drive it. Still a few other things to look at but it's coming along.

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Posted

Not speaking to Greg or Gw here, because I can see and know they are both thorough and logical, but for those that do struggle with electrical problems.. 

A "voltage drop test", is the way to find bad connections. Look it up and understand how it works.

We have to look for the bad connection with full load on the connection. We can go around watching milli-voltages, or checking resistances, and never find the bad connection (and associated voltage drop), if we are just depending on our super precise digital meter.. And for the same reason, most of the time it's best to use an old fashioned test light (with a bulb that uses a bit of power), to quickly trace power, rather than the digital meter.

And the other thing that I suspect causes a lot of difficulties and reluctance to do all the tests needed, is people try to work on their quad with all the body work on it. Most body work comes off relatively easily if the bolts are greased. Whenever a quad needs some work under the body work, it's nearly always worth taking the few minutes to pull the plastics off. And it's true of electrical as well as the fairly mundane, such as valve adjustment.. And it's a good time to check the wiring for chafing etc..

 

Posted

New belt installed and also did a 25 year overdue service on the primary drive, it was really nasty and corroded. It's working good now. Took it out of the shop yesterday and did some riding around the yard and it seems to be running well. I did track down another electrical issue that I'll take care of this evening. It would lose power to the main switch intermittently and I finally traced that to a terminal in the connector that plugs into the starter solenoid. I'm also going to flush the cooling system and install some antifreeze 

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Posted

Well after driving it around a bit and having to replace a stuck thermostat it seems to be running well and has good power

 I have noticed gear oil coming from the front diff pinion seal area so I guess I'll be exploring that issue sooner than later.

Posted (edited)

Good work. I like that you cleaned and inspected the drive system and didn't just condemn it out of hand, and then you got it working. Even if it does need a bit of work after a while it lets you test everything else. It's important we use our discretion when choosing what needs replacing.

That's good work..

Edited by Mech

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