Hisun vector 500 won’t start

[Pozz]

My hisun vector 500 will not start. It has spark and is getting fuel. It is currently in the low 20’s temp outside. Unit is in my barn but the barn isn’t heated. Could the no start be because of the low temps or something else? Unit only has about 20 hours on it.

[Savage3]

How did you determine the cylinder is getting fuel? Let us know the specifics of your troubleshooting steps thus far.

[Pozz]

I pulled the spark plug to check it. Checked the spark the old school way against a ground, it had good spark. There was a fuel smell on the plug. Cleaned the plug and turned the engine over with the plug out and fuel mist came out the cylinder. You can smell fuel when turning it over like it’s flooding. The engine acts like it wants to start once in a while. The unit sat for about 3 weeks before I moved it. It was hard to start then and the temp was in the low 40s. I added staybill to the tank before it sat for a while just in case.

[Savage3]

27 minutes ago, Pozz said:

I pulled the spark plug to check it. Checked the spark the old school way against a ground, it had good spark. There was a fuel smell on the plug. Cleaned the plug and turned the engine over with the plug out and fuel mist came out the cylinder. You can smell fuel when turning it over like it’s flooding. The engine acts like it wants to start once in a while. The unit sat for about 3 weeks before I moved it. It was hard to start then and the temp was in the low 40s. I added staybill to the tank before it sat for a while just in case.

Ok sir, check valve adjustment.  Sounds like they may need adjustment if you were struggling at 40 degrees.

Prior to that, I'd put a little fuel directly in cylinder through spark plug hole and see if she pops off.

Let us know the results

[Pozz]

The unit has the Delphi efi system on it. I will try the fuel on the cylinder . Thanks.

[Savage3]

8 minutes ago, Savage3 said:

Ok sir, check valve adjustment.  Sounds like they may need adjustment if you were struggling at 40 degrees.

Prior to that, I'd put a little fuel directly in cylinder through spark plug hole and see if she pops off.

Let us know the results

One thing I forgot to mention, try fresh gas, non ethanol if you can find it in your area.....drain the old gas out. Use new gas, about a teaspoon in cylinder.  I never use ethanol in small engines, stabil is not the best option either, try Startron

[Savage3]

Oh, thanks for the update. I thought it had carburetor.

My guess would be poor quality gas. Usually only takes a few weeks to create problems if it is ethanol.

I would purchase new gas, not from a can on your garage. Winter blend non ethanol would be the best option.

[kenfain]

4 hours ago, Pozz said:

The unit has the Delphi efi system on it. I will try the fuel on the cylinder . Thanks.

Does it have a check engine light on the instrument panel, that's lit? Any trouble codes at all?

[Dumbfounded]

I have similar problem only mine died while in use. I heard a slight pop right before it died. Then it would not start. 1st I checked was oil level and it was a bit higher than normal.  Removed spark plug boot placed test light in between and good. Removed plug and tested compression and had real good number considering it has less than 300 hrs. Listened for evi pressurizing and sounds good.  Added fuel since it was 1/3 on gauge and turned to on and off position 3 times then cranked but same issue.  What could have caused this and what to do next?

[kenfain]

Just like the op, who hasn't posted a follow up. Yours sounds like a sensor problem. Is there a trouble code? Maybe the dashboard clock is flashing?

[Dumbfounded]

No codes, no flashing on dash.  Trying to figure out what sensors it has and would pop before dying. Was cruising about 15 mph steadily when it all happened. 

[Savage3]

4 hours ago, Dumbfounded said:

I have similar problem only mine died while in use. I heard a slight pop right before it died. Then it would not start. 1st I checked was oil level and it was a bit higher than normal.  Removed spark plug boot placed test light in between and good. Removed plug and tested compression and had real good number considering it has less than 300 hrs. Listened for evi pressurizing and sounds good.  Added fuel since it was 1/3 on gauge and turned to on and off position 3 times then cranked but same issue.  What could have caused this and what to do next?

If you have fuel (fresh fuel), spark, and compression, I would look at timing. Is it sparking at the proper time? Is it possible the timing chain was loose causing the pop noise?

[Dumbfounded]

It's a 1 cylinder 2 valve engine. If timing chain jumped how can I diagnose the problem? Never popped before and pop was not loud. 

[Savage3]

Remove cam cover and inspect, see if timing marks are lined up.

Also look in hole on bottom case to see if the timing mark is lined up. 

See if chain still has tension as well.

Piston should be at top dead center compression stroke when timing marks are lined up.

I have seen the chains get loose and they skip a tooth or two.

I don't understand how it does it, but, it does.

Changes timing and pops out intake.

[kenfain]

First off, with only 300 hours, shouldn't this be a warranty issue?

It's got a crank position sensor that will tell the onboard computer where the crankshaft is. That will fine tune the timing. If that sensor  goes out, then it won't start, or run. But that should throw a code, so it might not be a sensor. 

It could easily be a fuel issue. Others here have had regular injector failures on these Chinese UTVs. So you should keep an open mind, and not start throwing parts at it.

First, I'd determine that the fuel pump is working, then pull out, and test the injector. If it has fire, and fuel, then it seems most likely to be timing, or possibly the CPU itself given the symptoms, and low hours. 

[Savage3]

The original post states that the machine has fuel, compression, and spark.

With a Hisun, low hours or miles means little to nothing.

I've had to rebuild top ends on basically new machines due to overheating among other issues.

These machines are riddled with problems. I wouldn't assume anything or overlook any possibilities.

If the machine has fuel, spark, and compression, logic points to the machine sparking at the wrong time.

Merely food for thought.....

[kenfain]

But you're not talking to the op. That was back in February. The member that you're talking to said only that he's added gas to the tank. Which means next to nothing. 

Of course nothing is assumed, even on a new machine. But it's exponentially more likely to be either an electrical component, or a fuel issue. On a 300 hour machine, the likelihood of a mechanical failure would be secondary to those two. 

[aefron88]

So you said you have spark, new fuel, fuel pulsing from the injector. What did you get for compression? This will confirm the valves are ok, rings are in decent shape, etc.

You could also spray some carb cleaner, a small amount of fuel, etc down the spark plug hole, put the plug back and try to start it. If it starts briefly and dies that would point to a fuel issue.

Once you confirm compression I second checking the timing chain based on the symptoms. Yes the crank position sensor will set the spark timing, but it has no way of telling the valves are in the right position. I have read of a fair number of timing chain tensioner issues, even on relatively low hour engines.

[Savage3]

8 hours ago, Dumbfounded said:

I have similar problem only mine died while in use. I heard a slight pop right before it died. Then it would not start. 1st I checked was oil level and it was a bit higher than normal.  Removed spark plug boot placed test light in between and good. Removed plug and tested compression and had real good number considering it has less than 300 hrs. Listened for evi pressurizing and sounds good.  Added fuel since it was 1/3 on gauge and turned to on and off position 3 times then cranked but same issue.  What could have caused this and what to do next?

Ok, so we go back to his original post. I was basing troubleshooting on this post . The popping sound is important. 

If it has fuel, spark, and compression ( assuming he made sure fuel is reaching combustion chamber and it's fresh) I would personally check timing next. The last one I rebuilt, the chain tensioner had a total meltdown with only 200 hours. Same symptoms as described.

[Dumbfounded]

Appreciate feedback.  As far as warranty  that expired. Original owner put 150 hr but hardly ever used it in the 3 years he had it. 50 of those hours were due to leaving ignition at the on position till battery died. I ve had it just over a year and use it primarily on weekends.  Still all original except oil and filter.  Seriously hoping it's not the timing.  Very difficult to pull cam off in such a tight fit area. Will try to find OBD hook up if it has one. 

[kenfain]

It has a Delphi hookup. So it won't have the automotive type OBD2 connection. 

[aefron88]

I have a post over on the coleman forum explaining how to get the Delphi code scanner working for around $25 in cabling, and free software.

 

3 minutes ago, Dumbfounded said:

Appreciate feedback.  As far as warranty  that expired. Original owner put 150 hr but hardly ever used it in the 3 years he had it. 50 of those hours were due to leaving ignition at the on position till battery died. I ve had it just over a year and use it primarily on weekends.  Still all original except oil and filter.  Seriously hoping it's not the timing.  Very difficult to pull cam off in such a tight fit area. Will try to find OBD hook up if it has one. 

 

[Dumbfounded]

Also I did remove fuel line at throttle body and plenty of fuel there when ignition is turned on. Sprayed starter fluid into intake and no start, not even a glimpse of want to ignite 

I agree the possibility of crank position sensor or even more so chain jump skipped a tooth setting it off time.  Will try cheaper route first with the CPS.

[Savage3]

Hot tip, a bad sensor does not create popping noise.

Also, the crank sensor will not know the chain has skipped a tooth.

If you want to test the sensor, I'm sure the service manual has specs. 

 

[kenfain]

Throwing parts at it isn't the best way. It almost never works out well. Patience and checking out all the possibilities first, is the best way. Besides that, it's free. Now we know that the fuel pump is working, you should verify the injector is working also. It's a process of elimination, and that would mostly eliminate the fuel system as the problem. 

Sorry, but I just saw your last post. If starter fluid doesn't work at all. Then you could probably hold off on the injector test. Please verify timing marks first, as the others have suggested. This issue needs to be put to rest.

Edited September 4, 2022 by kenfain
Extra information

[Dumbfounded]

 

[Dumbfounded]

Ok, going to test sensor first hopefully that is the problem.  If not I have a feeling the pop I heard may have been the sheer pin as described in link I just posted. I'd hate to go that far though. Gonna have to take her to my workshop for that.

[Savage3]

Set timing, turn motor slowly by hand ensuring valves move free. (At least 2 revolutions)

The key usually shears if wheels locked up or abruptly stopped. Generally, abuse causes key to shear.

Sometimes the chain tensioner loosens. The key doesn't always shear.

 

[Dumbfounded]

Thanks, will have to sit in shop till I find the time. Never abused it. Mainly used for cruising the community. 

[Dumbfounded]

Ok guys, opened up cam window and removed timing chain cover. Looks like the chain is free spinning behind the flywheel as when I give harmonic balancer one revolution chain rains in place and is overly loose. Have to buy a 3 prong pulley to remove sprocket as flywheel and magneto has been removed.  Wondering if chain sprocket behind water pump drive sprocket broke? Any thoughts or suggestions?