How To: Suzuki King Quad 300 Engine Rebuild 

Glad i can help Frank! Thanks for the comment!

Hey! Thank you. Finally someone that appreciates the camera work. Haha No issue with doing just one valve at all. Go ahead and see if that is your issue.

I really don’t think so no.

Haha that is how mine was. Be sure to check the air filter. You will love it when it does not smoke like crazy.

Very good method john. However i think the cylinder may hit getting it over the con rod. Hard to say. One way to find out😀 good luck!

Im about to find out. But i test slide the pin so..... Good to go the circlip is another story.. I always put towels in the case ... Just in case i drop it.

All great points👍🏻

Thanks Tom, yes camera’s have improved. No other videos on the rebuild sorry.

I would think once you slide the cylinder off that you will be able to get a vise grip down lower and be able to spin it out.

That is correct. You have to pull it. However that is to fix it properly. If you clean the surface very well with brake cleaner or something that gets 100% rid of residue i wouldn’t be against sealing it from the outside. It won’t look the nicest but just cover it in some RTV like permatex the right stuff and you will be set.

@@Schneids15 thanx. I'm gonna pull the valve cover and reseal it from the top end. Seems the leak is on top of the seal. Your video sure helps

Hey man, how long has it been sitting? If not too long yank the spark plug and full the cylinder with diesel. Let it soak for a few days and go over and give it a bump with the starter or pull start. If it starts to break free get some oil to the cylinder. Then try and fire it up. Most likely will need a gasket set and piston/ too end.

How long does it have to be sitting for that not to work

It usually breaks them free but compression is not usually the best.

Thank you sir. Start with a simple compression test to check. Also you can buy a leak down tester that is your best bet to tell the condition of your cylinder and where it is leaking. Rings valves etc. Mine was smoking like crazy when i bought it. Like fog bad haha. I knew it was time.

Schneids15 I did and the compression tester it only showed 35 on it. So I went over to my buddies and he has a little tank like this and his showed 160 on his.

The leakdown test is pressurizing the cylinder using air. If your compression tester is at 35 you definitely need a rebuild or something is going on.

Schneids15 really appreciate you getting back to me. I’m checking that out hopefully all I need is a rebuilt. Since you got it already about how much is a kit cause there different ones really don’t know which I need

Before I tore that engine apart I would check your intake valve adjustment these bikes have issues with them the symptoms you are describing screams valve issues Ive seen that is a lot I put 50,000 km on one of those engines

Not for the carb. Just the seat and intake boots.

Hey! I would thing a little force should pop it past and get it iff

I’m sorry i can’t remember off hand. It is either on the top or bottom. I would have to check the manual.0

@@Schneids15 i seen the one on top you done. I came home from the shop just to try ti download a manual. But hard to buy one for one question.

They are beasts that is for sure.

Have you tried to twist the idle knob to the lower right if you are sitting on the seat?

Hey Rob, have not had an issue with that.

Did you put the copper washer on the head bolt?

@@Schneids15 Hi mate thanks for the reply, Yes copper washers back in place and torqued down to 18 pounds. Engine starts first kick runs nice but I cant find the reason as to why it would leak out. I have stripped it twice since and cant see a problem. Doing my head in lol

@Rob Madaffari did you figure it out?

@@thepimpshitdan Hi mate yes it was the o ring which sits in the jug/head. It wasnt the right size and I did not know that you also had to use atv SIC in and around the ring and head bolt. As per instruction manual lol.

I would start with carburetor for sure.

voltage regulator needs replacing

Valve cover gasket for sure. Called chemical guys VRP the plastic restorer. Josh

Hey Paul. I think spec for a KQ for compression is somewhere around 180-220PSI. That could explain the hard starting and some issues. Have you ran it with the intake on? They act funny if the intake is not connected to airbox. They run lean and pop and run like crap.

@@Schneids15 I will try it with the intake on this evening. Sounds like the compression might be the problem if it needs at least 180. Thanks for the heads up

Hey, yes for sure.

@@Schneids15 Your videos have been super helpful. I appreciate your effort in making videos to keep these old quads running!

Thank you! I actually sold mine last winter, however before i sold it i made a large amount of videos because i loved the Quad and to help others like you! So i appreciate the nice comment. Josh

Likely bad rings or valve seals. Likely needs a top end rebuild.

Hey John. Let me look. I don’t know it off hand.

@@Schneids15 it's OK I already did it I put I to 19ftlbs seems fine

I used a winderosa complete gasket kit. Buy the full kit because you will need it in the future for other seals. I used a namura piston. Can’t remember the number.

Did you use the same valves or replace them?@@Schneids15

I replaced one as the other was wore due to it being run without an air filter. Otherwise i just lapped them.

@@Schneids15 Does the winderosa complete gasket kit include valve seals or do I have to buy those separate?

Yep it has the valve seals

It is homemade but i bought it with one of my past snowmobiles. Thanks!

You can get them from royal distributing for about 200$

I have honestly only heard of 300’s.... no bore kit as far as I’ve seen just oversized pistons.

Schneids15 Awesome. I knew aftermarket parts were very limited for these machines. Had a lot of fun of my old 98 as a kid all the way up until the end of my teens until I met my wife till she witness me roll one she wasn't about to witness another accident made me sell it. Took a few years to work her up to let me buy another one. Lol

Joe Ellis

Joe Ellis 331 kit mickey Dunlap at four stroke tech makes it comes with a larger sleeve and piston

Schneids15 how much was it to get the valve seats redone?

I haven’t had to touch anything on either of my king quads so i am not sure.

@@Schneids15 mine is well worked and so it needs a ring job, probably valve lash and lap, axles rebuild and suspension rebuilt.

If your in northern Indiana i can do that. Williams Small Engines... Google it check my pics of past projects

When i put mine together there was a little slack. The guides seemed fine but i thought the chain could be possibly stretched. Keep in mind once you start the bike and the chain flops around a bit it will ratchet out on the tensioner and slack it up.

I wouldn’t worry about it in other words. This atv is still going strong 2 years and almost 900KM later

well I was having an issue with this quad, it won't start and back fires out the carb. I checked the timing and it was off so I re did it and put it back together and it's doing the same thing. I'm going to pull it apart again tomorow and see if it's off again. do you know if this is an interference engine?

I believe they are interference engines yes. It sounds like if your timing was that far off it could be skipping like you are presuming. If these atv’s are run without the intake on and air filter they will backfire out the carb like that. They need the restriction so they run proper,

hmm maybe that's why mine won't start then. I'll try to hook the intake tube and if it don't run I'll check timing again

This depends... where are you located?

+Reno 2112 i measured the piston and con rod. Then lubed the wrist pin and con rod. Already had one circlip in the piston, right side since the left side of atv is easier to get to to put the circlip in once piston is in motor. Then installed it and rested it on the crank case studs. Got cylinder lubed and ready and slid the cylinder down the studs while holding the piston with my other hand, then go around and work the rings in to the land once cylinder is against the piston ( have piston as if it is at Top Dead Centre for room for your hands) then get the 2 compression rings in and the oil ring is the tricky one to squeeze in without damage. Make sure all rings are in the shape of a peace symbol the best you can( end gaps) and slide the cylinder down onto the base gasket. Then i usually put some gear oil or regular oil on the walls and pull the motor a few times to get oil on all the walls evenly. Make sure you hold the cylinder down or put the 2 10mm nuts on the bottom of the cylinder to hold it. Hope this helps!

Thanks man. i did basically the same thing only i used a large hose clamp to gently hold the rings in cuz i don't have a real ring compression tool. Almost done putting the exhaust back together...Pain in the Ass!!

+Reno 2112 Did the same thing just worked the rings with my finger! I suggest checking your oil pump strainer after the rebuild. I have a video on it.

Yes they are. There is the odd part that is no longer available. Plastics and such.. otherwise everything is.

@Schneids15 you can buy some decent aftermarket fairings in 4 colors, little over 700 for the set. Zmperformance, to steep for me despite mine being almost worst case scenario, tons of gorilla tape and zip ties but it's an option, make an old beater look fresh af

It's just a dirty carb, why does this guy not answer anyone's questions???

Hey it was actually a homemade snowmobile lift that ai used for this.

No idea on Hours. There was 5000 KM or so on it. It had been taken care of very badly and run without and air filter.

@@Schneids15 iv been running my 250 quad runner with no filter for a wile an now it smokes like nothing iv ever seen do u think i dicked it

The HONDACATS i would have to say by the sounds of it yes. All those very extra fine metal shavings do not mix well with the cylinder and rings. Time for a new too end i would think. Could also be something as simple as valve seals.

@@thehondacats5253 ur intake valve is getting chewed up by debris so yeah u kinda dicked er but I would adjust the valves put an air filter on it and change the oil clean the carb as for the smoking depends on if u like mosquitoes or not lol haha probly needs a rebuild but do all the other things so it lasts a bit longer

Hey terry, it is a clear just wipe on. I used stuff called chemical guys vinyl plastic rubber restorer.

Thanks Schneids. So it's just a cosmetic surface fix, not something which would fix cracks right through the plastic, right? I have cracks right through.

Yes just cosmetic and brings the colour back. I also have cracks they are very common on these.

It is a custom made one. Many people have them, it is primarily for snowmobiles but you can use it for atv’s and works very well. You can buy them at royal distributing.

Schneids15 do you have a link for the one you use?

No i don’t as it was custom made and wasn’t bought.

Probably the position switch sits on the selector shaft.

+CMac in terms of miles since rebuild or all together? 5500KM on it only about 100 since rebuild because i took it for its break in and oil change then she got bolted to the plow and stays to do the driveway for winter.

I was wondering since new, I'm looking at a 1994 with 2880 kms. Those Suzuki motors from that era are about tough as they come. Thanks for making the vid.

Hey William. I will at some point but now i have no place to work on them anymore. Sorry