Help! Predator 212 won't start no matter what I do

Mini Bike & Go-Kart Parts

#61
You need to verify that the slide is positioned correctly for it to idle and so the idle mixture screw will operate as it should. look at this link it shows some of the basics but not the slide height. you need to verify that when the throttle is closed that there is a bit of cable slack so the carb slide is all the way down. Mikuni Carburetor Tuning – Affordable Go Karts I have to go out but I will see if there are any good videos for you to watch. I looked on youtube but the ones I saw were not good. You need to understand the 4 stages of tuning for this carb. Right now we are just trying to get the 1 stage working which is the idle with throttle closed and running on the enrichment on setting. The problem is GPS had their hands on it then you got it and it did not work and you adjusted stuff some more so we need to start from ground zero. You have verified the engine starts on starting fluid so other than a air leak it sure looks like the carb is the issue. Keep in mind we are not there with you so we have to go with the test results you provide.
ok, i will take a look
thank you for being such a big help through all of this
 
#62
You need to verify that the slide is positioned correctly for it to idle and so the idle mixture screw will operate as it should. look at this link it shows some of the basics but not the slide height. you need to verify that when the throttle is closed that there is a bit of cable slack so the carb slide is all the way down. Mikuni Carburetor Tuning – Affordable Go Karts I have to go out but I will see if there are any good videos for you to watch. I looked on youtube but the ones I saw were not good. You need to understand the 4 stages of tuning for this carb. Right now we are just trying to get the 1 stage working which is the idle with throttle closed and running on the enrichment on setting. The problem is GPS had their hands on it then you got it and it did not work and you adjusted stuff some more so we need to start from ground zero. You have verified the engine starts on starting fluid so other than a air leak it sure looks like the carb is the issue. Keep in mind we are not there with you so we have to go with the test results you provide.
what are the symptoms of an air leak? i want to know so i can see if there is a leak between the gasket and the engine, cause i have seen starting fluid dripping from where the gasket was
 
#63
depends on how bad the air leak is. It will cause the motor to run lean. Did you use a aftermarket intake gasket? here are some pics of the manifold that yours should look like as well as a couple of aftermarket gaskets also pics of the float properly adjusted. See how float seam is level with the carb base. I have also included pics of the gasket, manifold carb together how it should be on your motor. Finally pics of the enrichment off (plunger down) then on with the plunger up.
 

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#64
depends on how bad the air leak is. It will cause the motor to run lean. Did you use a aftermarket intake gasket? here are some pics of the manifold that yours should look like as well as a couple of aftermarket gaskets also pics of the float properly adjusted. See how float seam is level with the carb base. I have also included pics of the gasket, manifold carb together how it should be on your motor. Finally pics of the enrichment off (plunger down) then on with the plunger up.
yeah this looks exactly how my carb is set up. ill check the float level when i get a chance tomorrow, as it was raining all day today.
 
#65
After you get the carb back onto the engine, and you try to start it, spray some brake cleaner around the manifold and try to start it.
If it runs or was running on gasoline and the brake cleaner is sucked into the engine because of an "air" leak it will speed up.
 
#66
depends on how bad the air leak is. It will cause the motor to run lean. Did you use a aftermarket intake gasket? here are some pics of the manifold that yours should look like as well as a couple of aftermarket gaskets also pics of the float properly adjusted. See how float seam is level with the carb base. I have also included pics of the gasket, manifold carb together how it should be on your motor. Finally pics of the enrichment off (plunger down) then on with the plunger up.
float level is correct and just like your picture
 
#68
So I have a non-hemi 212 predator, and it ran fine before I started doing mods to it. When I installed the stage 1 kit from GPS, I couldn't run the engine off of choke for more than a few seconds, and it would eventually die out anyway. I replaced the stock carburetor and it still did the same thing. Just yesterday I got a 22mm mikuni and slapped it on the engine, tried to start it, and it would still not start. I am at a complete loss right now, and have no idea what to do.
- has spark but the spark plug is wet (see picture)
- head is in similar condition to the spark plug (tiny bit of wetness and completely black
- key is not sheared on flywheel
- turns over fine, fights back
I've read multiple forum posts on here and people here seem to be really knowledgeable about this stuff, any help is appreciated
This kit is an intake improvement. If you increase the ability to flow air through the intake side, you *must* improve the flow of air through the exhaust side. This GoPowerSports kit is all about the intake side so you need to have some comparable improvement to the exhaust side. I would think the instructions with this kit would tell you what needs to be done with the exhaust side. Which I suspect is probably another "performance kit" from GPS. If this kit is designed to run with an open header pipe and you're running some kind of muffler ...especially if it's the stock muffler ...you're gonna have big time jetting/mixture issues. If you haven't made exhaust flow improvements, the engine will run rich ....which explains the wet, fuel fouled spark plug. A wet plug will generally not fire so don't check for a spark using a wet plug. The rules are the same for any engine, the 212CC Predator or a 455 Pontiac, if you improve one side of the engine (intake or exhaust) you must improve the other to get a properly running engine. It's even more poignant when dealing with just the intake side.

My advice? Pull off all the "performance mods", set things back to stock and get the engine running good in stock condition. If you have a California EPA carb (one not adjustable for idle mixture and idle speed) then drop about $18 and score an adjustable stock carb off Amazon. This may be part of your present problems. Make small, one at a time, improvements to the engine. You can get a lot of improvements that don't cost you squat with the stock engine. The stock intake can be improved by simply opening up the stock air cleaner box. The stock airbox is highly restrictive; cutting a 2" x 3" hole in the outer side of the airbox will improve breathing; stock main jet works if you leave the stock muffler in place. Go with a less retrictive exhaust and you'll need to get a slightly larger main jet. You can get a safely higher revving engine by making smart tweaks to the governor system ...plenty of info/how-to's on YouTube. IMHO, do not gut the governor unless you are gonna "blue print" the motor with a more robust con rod, balanced flywheel and higher spring rated valve springs. Otherwise you're tempting the fates. This is a "lawnmower" engine and designed for low performance and high longevity.
 
#69
This kit is an intake improvement. If you increase the ability to flow air through the intake side, you *must* improve the flow of air through the exhaust side. This GoPowerSports kit is all about the intake side so you need to have some comparable improvement to the exhaust side. I would think the instructions with this kit would tell you what needs to be done with the exhaust side. Which I suspect is probably another "performance kit" from GPS. If this kit is designed to run with an open header pipe and you're running some kind of muffler ...especially if it's the stock muffler ...you're gonna have big time jetting/mixture issues. If you haven't made exhaust flow improvements, the engine will run rich ....which explains the wet, fuel fouled spark plug. A wet plug will generally not fire so don't check for a spark using a wet plug. The rules are the same for any engine, the 212CC Predator or a 455 Pontiac, if you improve one side of the engine (intake or exhaust) you must improve the other to get a properly running engine. It's even more poignant when dealing with just the intake side.

My advice? Pull off all the "performance mods", set things back to stock and get the engine running good in stock condition. If you have a California EPA carb (one not adjustable for idle mixture and idle speed) then drop about $18 and score an adjustable stock carb off Amazon. This may be part of your present problems. Make small, one at a time, improvements to the engine. You can get a lot of improvements that don't cost you squat with the stock engine. The stock intake can be improved by simply opening up the stock air cleaner box. The stock airbox is highly restrictive; cutting a 2" x 3" hole in the outer side of the airbox will improve breathing; stock main jet works if you leave the stock muffler in place. Go with a less retrictive exhaust and you'll need to get a slightly larger main jet. You can get a safely higher revving engine by making smart tweaks to the governor system ...plenty of info/how-to's on YouTube. IMHO, do not gut the governor unless you are gonna "blue print" the motor with a more robust con rod, balanced flywheel and higher spring rated valve springs. Otherwise you're tempting the fates. This is a "lawnmower" engine and designed for low performance and high longevity.
let me get some things out in the air, the engine ran fine when it was completely stock (adjustable carb, stock box + muffler). as soon as i bought the "stage 1" mods (high flow filter, open header) the engine did not want to start at all. at the time I thought the carburetor was the issue, so i bought a replacement and fitted that to no avail. then i just decided to buy a mikuni and remove the governor. yet, i still have no luck in starting. Im considering doing a port/polish job for later on to improve flow just a bit more, but at this point in time i have no idea why it is not even trying. i do plan to get all of these internal upgradrs after i can get it idling and running fine. i donated the stock parts to my shop class to use for spares, so i have no idea where they could be right about now. thank you for taking the time out of your day to try and help me with this, highly appreciated
 
#71
At this point of frustration, you have a wet spark plug. And it is a quality brand,not Chinese crap.
You report that you have a blue/white spark out of the engine and not yellow.
The engine was working before the mods.
This can be caused by several things with the Mikuni carb as posted.
The plug is wet with gasoline so it is getting way too much gas into the cylinder.*
The float height is too high- you checked that
The choke is providing way too much gas- I'd try to start it it with no choke - Check the plug after this ans see if it is still wet.
The jets are too large for this engine
How "new" is the gasoline? What is the alcohol content?
*I would shut the gas off completely. Drain the float bowel. Pull the plug out and pull the engine over ten times and clear the cylinder. Keep the gas off. Plug back in.
Give the carb a squirt of Starting Fluid.Hold the throttle wide open to allow max air to enter The engine should run for a few seconds. If it does not you have no spark or the air is blocked for some reason. If it does run, then you know the carb is flooding the cylinder with gas.
When working alone it can be a daunting task to show what the culprit is for not running.

I myself, pull the rope starter off of the engine off and block the mini off of the ground on jack stands. I spin the engine over with a drill motor and check the see if the spark plug is firing on every stroke as it should and the color of the spark.
From there I adjust the carb to the minimum settings and slowly open the jet(s) until it fires. Once it fires you know your close to adjusting the carb to allow the engine to run.
 

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