New Guy, Busted 2000 Suzuki Quadrunner 500 Project

[USRaider]

Hello all!

I was given a 2000 Suzuki Quadrunner 500 (Quad 500 Runner?) and its current state is a bit of a mystery!  

Kept indoors but hasn't been run in 5 years.  We're not trying the engine until the gas is replaced, and the tires are reinflated. But the previous owner said their only issue was stalling when shifting to reverse without giving some throttle.

I'm optimistic!  See y'all around!

[Mech]

Score !

[USRaider]

2 minutes ago, Mech said:

Score !

Score indeed!  Well, assuming it will chooch.

[Gwbarm]

A good find indeed, sounds like its an easy fix once you get it up and running so you can see what its doing, stored inside is a big plus!👍

[USRaider]

2 minutes ago, Gwbarm said:

A good find indeed, sounds like its an easy fix once you get it up and running so you can see what its doing, stored inside is a big plus!👍

Very considerate family, I can take no credit for finding it!

[paradiseestatesales]

Very cool! Hope it vroooms soon

[USRaider]

Thanks Paradise, me too.  It'll be a learning opportunity for sure. I've been  part of small engine repair for a long time, but have never been more than the family gopher.  

 

Slow and steady, lots of reading manuals and documentation, and lots of learning  ahead.

[paradiseestatesales]

14 minutes ago, USRaider said:

Thanks Paradise, me too.  It'll be a learning opportunity for sure. I've been  part of small engine repair for a long time, but have never been more than the family gopher.  

 

Slow and steady, lots of reading manuals and documentation, and lots of learning  ahead.

Patience goes a long way, and for me, the help of a retired veteran/driveway mechanic. He amazes me with how much he knows firsthand about engines and especially motorcycles and he is excited about a new project.

[Gwbarm]

I was just reading about it, sounds like a great machine, good luck getting it going.

 

QUADRUNNER LT-F500FY The LT-F500F has been designed as a heavy-duty fulltime four-wheel-drive machine capable of pulling heavy loads, but agile enough to maneuver through tight terrain and fit in a standard size pickup truck. For 2000, the F500F has upgraded suspension with more wheel travel, increased ground clearance, 30mm longer wheelbase and new graphics. The 493cc, liquid cooled engine is tuned for high torque at low rpm, with power transferred through a 5-speed transmission with an automatic clutch and a 2-speed sub-transmission, plus a reverse gear. A unique torque-sensing limited-slip front differential provides fulltime 4-wheel drive traction. The LT-F500F’s frame is made of large diameter, thin-walled tubing and is supported by an independent double A-arm front suspension and 4-link rear suspension with a preload adjustable shock absorber at each wheel. Large, 25 inch front and rear tires mounted on cast aluminum wheels provide ample traction and a smooth ride. Hydraulic front disc brakes and a sealed drum rear brake are standard equipment. Other features include a 325 watt charging capacity, dual 12V DC accessory outlets, twin headlights and taillights, large racks and storage compartment, speedometer and fuel gauge, and a high towing/carrying capacity. Suggested Retail: $6,299

[USRaider]

Finally got the thing home to start picking away at.

 

Yikes!  Petcock dead, all my oil was gasoline, and I'm guess the carb is all chunked up. Lots of fun ahead!  

[Gwbarm]

That part shouldnt be too bad i would try to clean up the original carb if it is still an OEM carb, Mikuni or Kei Hin hopefully its not full of white powder that is the metal corroding down and sometimes actually destroys the integrity of the carb. 

[USRaider]

Carb not yet touched, but the coolant reservoir looked off. Two different colored fluids.  Oil got in there.

Couldn't drain it without removal, so I figure I ought to replace the tubes while I'm at it.

Thinking new seals everywhere are in order.  This will take some time.

 

[Gwbarm]

Sounds like you may have a head gasket leak.

[USRaider]

Just now, Gwbarm said:

Sounds like you may have a head gasket leak.

I think you're right!

[1954JF]

Hello New Guy, haha me too. I just did this project with a 1998 that I blew $1000 on to begin with. It was an Ugly Stick! It's not completely finished yet after months of spare time tinkering. A lot of reading and researching things. You can toss that crap vacuum operated Petcock for a simple mechanical one that cost very little and they work perfectly since this is gravity feed. The one I used was for a Yamaha Raptor? I can look back for the part number if you like this idea. The vacuum port on the carb will need a cap or plug it, that's all. The design intention was to shut off gas flow when engine is off. Maybe safe when your upside down with a hot engine on top of you but not something I plan on doing. I can turn the valve ON or OFF manually just fine and I know what I got without the worry of this diaphragm working or not and leaking thru. The 1998 has a Mikuni CV series and it's a very simple carb. I had a hell of a time getting the factory setting for the float which had been 'tuned' to never close the inlet , this is the the way I found it. Thus allowing gas through all the time and with this float needle adjusted incorrectly it ran terrible rich, and it would hydraulic lock the cylinder overnight, which I found out my second day of ownership. Thus a little gas in the oil. Float setting is critical for optimum running, (so I learned). I had the carb off three times just guessing on it until I finally got to read the manual from this website. (a Tremendous thanks to a generous member.) Forth time on this carb off was the charm. Mine had a deteriorated diaphragm in both the petcock and the carb to begin with. Two large cans of Gumout Carb Cleaner and a toothbrush and torch cleaning wires got it all cleaned up. Look through every jet too if you do this. A kit with the diaphragm plus a few brass items and tiny spring and O-ring for the pilot needle (which were not present when I took it apart) completed the carb fix. After getting the proper float height it purrs like kitten at idle and roars like a lion as you rev it up. Power and torque describe this oldie. Do not run alcohol or ethanol enhanced gasoline in these older machines. My exhaust system had been boogered up quite a bit also. I removed it all and had to fix the header pipe which was crushed by an automotive type U-bolt clamp and also the muffler pipe crushed the same. No sleeve gasket was present there where it belongs on this slip-joint and the header pipe was missing the ring gasket to the head. I purchased a pipe expander tool and hammered out the slip joints as good as I could get it. I bought both gaskets online, plus I brazed a hole in the pipe and placed a new nut on the damaged end of the muffler pipe which holds the heat shield attachment bolt. Worked for a few days with wire brush and sand paper to remove surface rust cleaning it all down to metal (several pieces/parts) then sprayed it with 2000 degree ceramic paint. It is holding so far. New oil, new filter, new sparkplug, new air-filter, new rectifier, new battery, new tires, purchased a plastic welding kit and a hot-stapler plus stainless staples and wire mesh and plastic welding rods to repair fenders (mostly the mud flaps), new seat cover, removed the racks, foot rests, and several other parts like front bumper and lights, belly pans rock guards, shocks, all were wire brushed sanded and painted. The rusty shoulder bolts that fasten the fenders are needing recoating and I'm thinking gun bluing solution to remain original looking. I used acid to remove the rust. This was an outdoor farm vehicle? It's all there and it is a solid runner now. Every part seems tight and right. Shifts solid and brakes are good too. I used linseed oil-turpentine solution on the plastics to renew the finish. It is slow drying but works great. I figure after gun-bluing the fender bolts they will get the oil finish too. I would rather buy new shoulder bolts but don't know where, these are button-heads and metric with a specific shoulder diameter and length. The rectifier was another new experience for me. I did not know they could allow overcharge or high voltage in the system. The ICM box communicates with the rectifier and limits the engine from revving too many rpms so as to hold voltage down if this rectifier fails it's purpose on the high side. Yep, mine would not rev-up without sputtering and bogging but it idled just fine. This overcharge could ruin a $650 ICM box (no aftermarket?) or blow fuses and maybe melt wires. That was in the mix when I stated this project. I added a Voltage gauge now so I know what I got for output and battery condition. Whew.. a learning experience. You can view the manual from this site. Replacement parts are available but not much for OEM out there. No body plastics at all that I could find. Too bad ..these are great ATVs. Stick with it and learn something. The guys here (or gals) can help you and encourage you too. The original carbs are the way to go if possible (in my opinion). Oil in the coolant bottle sounds like a head gasket but you can rent a tool from many auto-parts stores to test that theory. Autozone or O'Reilly. Radiator pressure check is a simple hand pump attached in place of the radiator cap it also includes a pressure gauge and you pump-up pressure and watch the gauge to see if it holds steady or leaks down. Sometimes used to find or see external leaks like pinholes in hoses or radiator coils, but also if it's a head gasket leak the gauge pressure will fall off. Enjoy these things or you could sell it to me if you like. haha, just have fun and swear a lot while fixing things. Jack ..out

[USRaider]

An update:

We have liftoff! Turns out the coolant wasnt leaking into the crank case, it was gasoline. 

I bought an oem mikuni carb rebuild kit, and worked with the best carbeurator mechanic I know (paternal unit 01) to clean and refit it.

We cleaned the gas tank out using a compressor, oxygen tube, and some old air line to make a vacuum hose that wouldn't ignite fumes. There was more debris in there than I could get without it! I installed a new yamaha petcock that has an off position to avoid the leak that we think caused all the issues.

After installing the new spark plug we ran it, in neutral on blocks, three times with an oil and filter change each time.  Disgusting, milky, dirty oil the first time. Cleaner slightly cloudy oil the 2nd. And now perfectly clean oil the 3rd.

I am installing a new filter and filling it up with new Mobil 1 15w-50 oil to give the wheels their first spin later today. (I chose the most available mobil 1 oil that fit the chart in the owners manual. The original spec weight was not readily available.)

We had a loose connector arm (tie rod?) at the front left, but I added a washer to and tightened up the bolt on each end. The ball may be almost entirely worn (unless those bolts stretched with previous wear) but it's tight enough to test.

The coolant was suppsoed to get flushed, with dostilled water after I previously dumped it. But an error led to it being filled directly with more coolant. I'll flush that out and add more coolant after. I'm hoping to avoid a negative interaction between the new stuff and whatever was in there.  New stuff should be compatible with the oem stuff, but we have no clue if that's what was actually there.

I am still having a bit of a backfire issue, and may be running lean at idle, so I'll need to figure out  why that is, and how to fix it.  Some sources say it's an open vacuum line, so we replaced the bolt-in-line on the vacuum port with a bigger bolt and more clips.  (The line used to go to the oem petcock, but we no longer need that.)

I haven't yet needed to tear the top end down, so that is a small victory!

Fingers crossed.

 

[USRaider]

She runs now, and does so fairly reliably. I still have a few bugs to work out, but haven't had the time to fix them yet.
 

• Starting cold takes a significant amount of time, and there is no consistent solution with the choke.  Sometimes it likes full choke, usually it doesn't.
• The cooling fan runs almost all the time, which seems strange to me on those super cold days. This may be normal, I'm not sure.
• The exhaust backfires occasionally, I'm not sure if this is due to excessive ignition attempts, or if something else is going on.
• This thing will stall and die quickly if the choke is taken off. I've got to keep an ear out while warming it up, and adjust the choke down as it begins to race.  This is a slow process, as the engine will die almost immediately if choke isn't reduced in  small increments several minutes apart.
• The fuel gauge is non functional. I haven't decided if I'm buying an amazon/ebay replacement, or fixing the original.
  
   

Overall, once I remembered to turn the gas off manually it has been reliable enough to take short loops across the property. I'd like to make it just a little bit more reliable before I trust it for work around the property.

[mtnous1]

looks like a great bike. should be lots of fun. Good luck!