Engine electrical issue

[ibkevman]

I'm looking for a little guidance for an electrical problem I'm having with an Intrepid 50cc 2-stroke racing go kart.

Background: I was told the kart would run at idle but as soon as you put it under load (a kid in it) it would bog and die. I figured a good carb cleaning would help but I wanted to see how it acted when started (this is where the problem began because I should NOT have agreed to work on this thing at all). Long story short is I was cranking it for too long and the current got the battery connections hot enough to melt the plastic clips and it shorted out. When I plugged everything back up and hit the starter, it just clicked but didn't turn over. There is a relay right after the battery and before the starter so I thought I popped it. I replaced it with one I bought online and same problem.

The clicking sounds like it's in the relay.
The battery is charged.
I examine it thoroughly but initial looks showed no fuses in line that could be popped.
I wonder if I fried the starter?

Clearly I'm not the best mechanic around but I'd love some troubleshooting tips or recommendations near STL on places to take it. Eventually I'd like to have the carb cleaned out too so any known pitfalls in this area would be appreciated. Thanks in advance for any help.

 

[BirdFanatic]

thats not 50cc thats 100 HPV

 

[ibkevman]

So it's a 100cc motor? Ok. Good to know. It's my neighbor's kart that I'm trying to help him get running and sell. So far, it's not going well.....

 

[anderkart]

I'm looking for a little guidance for an electrical problem I'm having with an Intrepid 50cc 2-stroke racing go kart.

Background: I was told the kart would run at idle but as soon as you put it under load (a kid in it) it would bog and die. I figured a good carb cleaning would help but I wanted to see how it acted when started (this is where the problem began because I should NOT have agreed to work on this thing at all). Long story short is I was cranking it for too long and the current got the battery connections hot enough to melt the plastic clips and it shorted out. When I plugged everything back up and hit the starter, it just clicked but didn't turn over. There is a relay right after the battery and before the starter so I thought I popped it. I replaced it with one I bought online and same problem.

The clicking sounds like it's in the relay.
The battery is charged.
I examine it thoroughly but initial looks showed no fuses in line that could be popped.
I wonder if I fried the starter?

Clearly I'm not the best mechanic around but I'd love some troubleshooting tips or recommendations near STL on places to take it. Eventually I'd like to have the carb cleaned out too so any known pitfalls in this area would be appreciated. Thanks in advance for any help.

[/URL]

You need a multi-meter or any type of voltmeter that reads DC-voltage to diagnose the problem.

Start by connecting your volt meters ground wire to any clean metal portion of your starters metal housing , and leave it there for all the following tests:

Then connect your voltmeters red (+) leed to the battery's positive (+) post, and read the voltage while your trying to start the engine.

#1- How many volts did the volt meter show?

_______________

Next, test the voltage at all of the starter relay terminals while trying to start the engine.

How many volts did that test show at the:
#2- Battery cable in to starter relay:
#3- Battery cable out from relay to starter:
#4- At the small wire from starter button:

________________

Next test is: how many volts your reading at the starter when your trying to start the engine.

#5-How many volts did that test show?

________________

This final test will be simply confirming you have a good ground connection to the starter, and its simply repeating all the above tests with the exception of first connecting the voltmeters black (-) probe to the negative post of the battery, instead of the starters metal housing. Its fairly normal to loose maybe like a 1/2 volt through either of your battery cables while under the load of staring the engine. So you should expect the voltage readings to be just slightly higher during these final tests of your ground circuit.

Post your voltage readings and we'll help you diagnose the problem

 

[ibkevman]

First and foremost, thank you very much for taking the time to give me the step by step instructions. I truly appreciate you taking time out of your day to help a noob like me.

I've included the results in the quote below bolded and underlined:

You need a multi-meter or any type of voltmeter that reads DC-voltage to diagnose the problem.

Start by connecting your volt meters ground wire to any clean metal portion of your starters metal housing , and leave it there for all the following tests:

Then connect your voltmeters red (+) leed to the battery's positive (+) post, and read the voltage while your trying to start the engine.

#1- How many volts did the volt meter show?

13.1 both sitting and when I hit the starter

Next, test the voltage at all of the starter relay terminals while trying to start the engine.

How many volts did that test show at the:
#2- Battery cable in to starter relay: 13.08 sitting and when pushed
#3- Battery cable out from relay to starter: 12.8
#4- At the small wire from starter button: 12.7

________________

Next test is: how many volts your reading at the starter when your trying to start the engine.

#5-How many volts did that test show? 13.06

This final test will be simply confirming you have a good ground connection to the starter, and its simply repeating all the above tests with the exception of first connecting the voltmeters black (-) probe to the negative post of the battery, instead of the starters metal housing. Its fairly normal to loose maybe like a 1/2 volt through either of your battery cables while under the load of staring the engine. So you should expect the voltage readings to be just slightly higher during these final tests of your ground circuit.

All of the tests were just about dead on with the first readings +/- a few hundredths.

Post your voltage readings and we'll help you diagnose the problem

 

[ibkevman]

Since there is power getting to the starter, it sounds like that might be the culprit. I've searched the net and and having a hard time finding a replacement starter for a HPV 100 engine. Any ideas where to look? Also, any idea how to ID the engine to be positive what I have?

 

[anderkart]

Good job! You've confirmed your starter is getting all the power it needs to work.

Assuming your engine isn't seized, your starter is defective. Its brushes might just be worn out, or sometimes the brushes just get stuck in their brush holders. Try giving the starter a few light taps with a hammer while your holding the starter button down and see if it starts working again, I'll bet you a doughnut it will

 

[ibkevman]

I'm sure the engine isn't seized because it was running 5 min before "the incident." Going to get my 5lb sledge now...........

 

[ibkevman]

Well, the hammer didn't work. The starter wasn't even spinning so I took it apart and there is some damage to the brushes and the plastic housing that holds them in place. It says it's a Mitsuba SM10 but I'm having a hard time finding a replacement online. Any tips or local folks that might have one?

 

[anderkart]

Does the engine have any brand and/or model numbers you could post?

Are you located in the USA or ?

 

[anderkart]

Is it this engine?
https://www.google.com/search?q=min...VdaoFIbIogTzkIGgBw&ved=0CCgQsAQ&dpr=1#imgrc=_
https://www.google.com/search?q=min...ei=8eFpVeGKDIKYNsypgfgI&ved=0CAYQ_AUoAA&dpr=1

 

[ibkevman]

I tried to put in my city in my profile the other night and I guess I didn't hit SAVE. Yes, I'm in St. Louis, MO.

Looks like it's a Parilla IAME (a very dirty and greasy one).

 

[ibkevman]

I think I just got lucky and found one on eBay that looks EXACTLY like the one off the kart. It says it's for a 60cc motor. I need to clean that thing up and look closely and find out if it's 100cc or 60cc.

FYI, this is my neighbor's kart that I'm trying to help him sell. I would have asked for more details if I were buying it.

Thanks again, anderkart for your responses/help. Fingers crossed what comes in the mail from the eBay auction works. If so, I promise to stop working on motors, especially ones that aren't mine.

 

[ibkevman]

Well, the starter was the culprit. Kart starts up just fine now but for some reason, it bogs when put under a load. It just needs a good tune up probably. It's off to Craigslist now to a new home hopefully.

Thanks again for everyone's help!