Help starting gokart

rls8836

New member
Messages
23
Reaction score
21
This gokart is a Trail Master mini xrx with a 5.5 horsepower which has No identifying engine name. I’m assuming a Honda replica.
I’ve posted 2-3 times already and still need help with a gokart. Son in law bought it about 3 yrs. Ago. They broke the axle and they threw into a utility trailor. Thought I would fix it for them so im going to try to get everything in sequence here what I’ve done. I’ve tried posting pictures before but the file is always to big and I don’t know how to resize them.
I got it home and cleaned it up some all around, I bought a new axle, chains, air filter cover, and eventually bought a new carburetor.
When I first got it running with new axle, original carburetor, chains and air cleaner top, I had disassembled the carburetor and cleaned it well. I had cleaned the gas tank well also. I had it idling several times but when I would try to accelerate the motor gently with the gokart on stands wheels off the ground it would labor knock loudly like 2 times and go dead. This happened 3-4 times so I decided to go back further and check the spark and air gap.
I removed the flywheel and the half moon keyway looked perfect, I cleaned the flywheel magnets and the coil . I set the air gap at .020. I checked the valves and pulled the pushrods they looked straight, reassembled the lifters setting intake on .004 and exhaust on .006. I checked the spark plug and made sure it was gapped correctly. I’ve laid the plug on the side of the motor and turned it over and I see good spark going on.
With my Snap On compression tester I’m only showing 30 psi. Someone here said a compression tester would not show accurately on this engine. I removed the old carburetor again and it was deteriorating inside, so I ordered a new carb. The same as the original and installed it.
Now with valves set, air gap at flywheel set, spark plug gap set, and new carburetor it will not start. Fuel filter is freely flowing. I’ve dipped spark plug in gas and tried it and it doesn’t hit. I’ve removed the 10 mm screw at bottom of the carb. and gas is running out well.
Could a compression release be causing me problems. I have no experience with a compression release. When I set valve clearance I removed the spark plug and inserted a thin screw driver down to the piston and rotated the engine to where both valves were open and piston at top. The valves were loose. I rotated again and with the piston up the next time at least one of the valves was tight. I rotated the engine again with piston at the top and both the valves were open, this is where I did the valve adjusting at.
I’ve had it running previously maybe two weeks before but after ordering carburetor there was a week or so delay before now. Now with all clearances rechecked and set and a good new carburetor, air cleaner, fresh clean gas, good fuel flow I’m not getting it to start.
Initially he paid about $1400, I’ve put about $160 in it and lots of cleaning, inspecting everything. Is it time to quit on it, buy a new motor? Any ideas to what I’m overlooking or doing wrong? Thanks to anyone who can help and thank you to everyone who has responded before. Today Harbor Freight has a 25% off coupon with today the last day to use it. I’m thinking of buying a 6.5 engine, don’t know what I should do.
 

bob58o

SuckSqueezeBangBlow
Messages
9,659
Reaction score
1,731
Location
Chicago-town USA
Air, Fuel, Spark, Compression, and Timing….
It’s all you need to turn gas to fun.

Timing…

I assume the flywheel woodruff key is in good shape so the spark timing should be good. They do break sometimes.

Is the camshaft timing correct?
There are dots on the camshaft and crankshaft gears that need to be aligned

Spark…

Have you verified that you are getting spark? Take the plug out, connect the wire, lay the plug on a bolt in the block and watch for spark as you pull the cord. Spark should jump from electrode to the bolt.

Compression…

Did you set valve lash at top dead center between the compression stroke and the power stroke?
 

BrownStainRacing

Well-known member
Messages
1,368
Reaction score
1,456
This gokart is a Trail Master mini xrx with a 5.5 horsepower which has No identifying engine name. I’m assuming a Honda replica.
I’ve posted 2-3 times already and still need help with a gokart. Son in law bought it about 3 yrs. Ago. They broke the axle and they threw into a utility trailor. Thought I would fix it for them so im going to try to get everything in sequence here what I’ve done. I’ve tried posting pictures before but the file is always to big and I don’t know how to resize them.
I got it home and cleaned it up some all around, I bought a new axle, chains, air filter cover, and eventually bought a new carburetor.
When I first got it running with new axle, original carburetor, chains and air cleaner top, I had disassembled the carburetor and cleaned it well. I had cleaned the gas tank well also. I had it idling several times but when I would try to accelerate the motor gently with the gokart on stands wheels off the ground it would labor knock loudly like 2 times and go dead. This happened 3-4 times so I decided to go back further and check the spark and air gap.
I removed the flywheel and the half moon keyway looked perfect, I cleaned the flywheel magnets and the coil . I set the air gap at .020. I checked the valves and pulled the pushrods they looked straight, reassembled the lifters setting intake on .004 and exhaust on .006. I checked the spark plug and made sure it was gapped correctly. I’ve laid the plug on the side of the motor and turned it over and I see good spark going on.
With my Snap On compression tester I’m only showing 30 psi. Someone here said a compression tester would not show accurately on this engine. I removed the old carburetor again and it was deteriorating inside, so I ordered a new carb. The same as the original and installed it.
Now with valves set, air gap at flywheel set, spark plug gap set, and new carburetor it will not start. Fuel filter is freely flowing. I’ve dipped spark plug in gas and tried it and it doesn’t hit. I’ve removed the 10 mm screw at bottom of the carb. and gas is running out well.
Could a compression release be causing me problems. I have no experience with a compression release. When I set valve clearance I removed the spark plug and inserted a thin screw driver down to the piston and rotated the engine to where both valves were open and piston at top. The valves were loose. I rotated again and with the piston up the next time at least one of the valves was tight. I rotated the engine again with piston at the top and both the valves were open, this is where I did the valve adjusting at.
I’ve had it running previously maybe two weeks before but after ordering carburetor there was a week or so delay before now. Now with all clearances rechecked and set and a good new carburetor, air cleaner, fresh clean gas, good fuel flow I’m not getting it to start.
Initially he paid about $1400, I’ve put about $160 in it and lots of cleaning, inspecting everything. Is it time to quit on it, buy a new motor? Any ideas to what I’m overlooking or doing wrong? Thanks to anyone who can help and thank you to everyone who has responded before. Today Harbor Freight has a 25% off coupon with today the last day to use it. I’m thinking of buying a 6.5 engine, don’t know what I should do.
I suggest you use the HF coupon on the Predator 224, not the 212. But, thats your call.

I like torque to the tires asap.
The 224 will do that faster and harder then the 212. Can pull more weight at less rpm, also.

Put the old engine on the work bench, when you get time go thur it and learn how these lil engines work.
 

rls8836

New member
Messages
23
Reaction score
21
Air, Fuel, Spark, Compression, and Timing….
It’s all you need to turn gas to fun.

Timing…

I assume the flywheel woodruff key is in good shape so the spark timing should be good. They do break sometimes.

Is the camshaft timing correct?
There are dots on the camshaft and crankshaft gears that need to be aligned

Spark…

Have you verified that you are getting spark? Take the plug out, connect the wire, lay the plug on a bolt in the block and watch for spark as you pull the cord. Spark should jump from electrode to the bolt.

Compression…

Did you set valve lash at top dead center between the compression stroke and the power stroke?
The flywheel is good, spark verified, I believe top dead center was verified. The camshaft timing, how do I see the dots you are telling me about?
 

bob58o

SuckSqueezeBangBlow
Messages
9,659
Reaction score
1,731
Location
Chicago-town USA
If both valves were open and piston was at TDC, you have set valve lash between exhaust stroke and the intake stroke.

you want to set lash at TDC between compression stroke and power stroke.

as you can tell, I’m opposed to reading posts. Lol
 

rls8836

New member
Messages
23
Reaction score
21
I suggest you use the HF coupon on the Predator 224, not the 212. But, thats your call.

I like torque to the tires asap.
The 224 will do that faster and harder then the 212. Can pull more weight at less rpm, also.

Put the old engine on the work bench, when you get time go thur it and learn how these lil engines work.
Going up to Harbor Freight soon is predator 224 identifiable with a tag.
 

BrownStainRacing

Well-known member
Messages
1,368
Reaction score
1,456

rls8836

New member
Messages
23
Reaction score
21
If both valves were open and piston was at TDC, you have set valve lash between exhaust stroke and the intake stroke.

you want to set lash at TDC between compression stroke and power stroke.

as you can tell, I’m opposed to reading posts. Lol
If both valves were open and piston was at TDC, you have set valve lash between exhaust stroke and the intake stroke.

you want to set lash at TDC between compression stroke and power stroke.

as you can tell, I’m opposed to reading posts. Lol
Thank you, are you saying I set the valves on the wrong stroke? If so guess I messed up.
 

Denny

Canned Monster
Messages
10,900
Reaction score
7,202
Location
Mayberry, Indiana
There is the very real possibility of junk plugging up the brand new carburetor. Dipping the spark plug directly into gasoline is probably the worst idea you had. Instead drip some directly into the cylinder. Or use some starting fluid sparingly.
 

rls8836

New member
Messages
23
Reaction score
21
Thanks to everyone that has replied. I appreciate the videos I was prompted to look at. I went ahead and bought the predator engine this evening and was told my 25% didn’t apply to this engine. Disappointed in hearing that! I think before giving up tomorrow if the weather permits I am going to remove the new carburetor and see what it looks like inside and blow air thru it. A retired small engine friend has said the air gap should be .010. I will adjust that along with the carburetor cleaning. My valve setting procedure was done correct according to the u-tube video! Will blow air into spark plug hole and dry it out and start fresh.

If it doesn’t hit and start this motor is coming off. Now with the new Predator engine having a gas tank I will remove the existing one. I be be losing the electric start feature and the ignition key will no longer function. 10W30 appears to be the recommended oil. Both shafts are 3/4” so my clutch should hook right up. Probably take me 2-3 days to get everything together. Thanks for everyone who answered.
 

BrownStainRacing

Well-known member
Messages
1,368
Reaction score
1,456
Thanks to everyone that has replied. I appreciate the videos I was prompted to look at. I went ahead and bought the predator engine this evening and was told my 25% didn’t apply to this engine. Disappointed in hearing that! I think before giving up tomorrow if the weather permits I am going to remove the new carburetor and see what it looks like inside and blow air thru it. A retired small engine friend has said the air gap should be .010. I will adjust that along with the carburetor cleaning. My valve setting procedure was done correct according to the u-tube video! Will blow air into spark plug hole and dry it out and start fresh.

If it doesn’t hit and start this motor is coming off. Now with the new Predator engine having a gas tank I will remove the existing one. I be be losing the electric start feature and the ignition key will no longer function. 10W30 appears to be the recommended oil. Both shafts are 3/4” so my clutch should hook right up. Probably take me 2-3 days to get everything together. Thanks for everyone who answered.
Which predator did you get?????

You can still use the electric start IF you got the 212 non hemi version or the 224. The parts swap right over, no big deal, ez pz.

The 212 hemi version uses a different flywheel, and WILL NOT interchange.

The stock fuel tank on the predators MIGHT sit too high for the rack on the kart.

I learned that the hard way when I put a 212 on my grandsons buggy. Less the 15 mins the tank got smashed from the suspension travel and started leaking around the hold down bolts.

Stock coil air gaps should be .030"-.035".

Too close to the magnet will burn out the coil.
 

rls8836

New member
Messages
23
Reaction score
21
I got the 224 I believe, 6.6 hp. What parts do I swap to do this. Are you sure about the air gap on the flywheel? If so I’ll set it to that tomorrow. Maybe it will start then. Let me know about the electric start swap over. The new motor doesn’t have it and would be nice for my granddaughters if I could put it on the new engine. I just looked it is the 224. Maybe it will work
 

BrownStainRacing

Well-known member
Messages
1,368
Reaction score
1,456
I got the 224 I believe, 6.6 hp. What parts do I swap to do this. Are you sure about the air gap on the flywheel? If so I’ll set it to that tomorrow. Maybe it will start then. Let me know about the electric start swap over. The new motor doesn’t have it and would be nice for my granddaughters if I could put it on the new engine. I just looked it is the 224. Maybe it will work
Yeap I'm very sure. It might not be your problem with starting as you have fire, but it will let the coil last longer.

Heres a stock coil set at .045", on my grandsons mini bike. That's not a stock flywheel, it's got hotter magnets in it then stock. But you can clearly see.... its not .010"

20230327_143752.jpg

You need to use the flywheel, charging/lighting coil(s), the small shroud between the blower housing and the block (behind the flywheel), off the old engine.

If the new fan does not go flush against the old flywheel, you will need to use the old fan, blower housing, starter cup, and recoil.

It depends if the fan fits or not. It's gotta be flush against the flywheel or it will fly apart.

I know I've got most of these parts in the shop. I can get pics if you need them.

I suggest you run the new engine a few hrs before swapping things over.
Jus incase theres something internal wrong with it.

And PLEASE go around and check every nut and bolt and make sure they are tight, before you start it. I had 1 that the flywheel nut was so loose it spun the starter cup the 1st time i pulled the rope.

These things are mass produced and not perfect.
 

Attachments

  • 20230327_143752.jpg
    20230327_143752.jpg
    1.5 MB · Views: 1

BrownStainRacing

Well-known member
Messages
1,368
Reaction score
1,456
@rls8836

I forgot the most important part......the starter, 😆 🤣 😂 😹.

You will need to use the old blower housing, starter cup, fan, and recoil.

The old blower housing has a hump on it for the starter. The new housing won't clear the starter.

These are all external parts and should bolt right up without any problems.
 

rls8836

New member
Messages
23
Reaction score
21
@rls8836

I forgot the most important part......the starter, 😆 🤣 😂 😹.

You will need to use the old blower housing, starter cup, fan, and recoil.

The old blower housing has a hump on it for the starter. The new housing won't clear the starter.

These are all external parts and should bolt right up without any problems.
Great that sounds good, tomorrow maybe I can work on it. Supposed to rain tonite and it’s all outside covered up. I’m hoping the throttle cable will hook up also.
 
Top