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Discussion Starter #1
Okay I have 2012 RZR 570. It would not start yesterday unless I pushed down on the accelerator. Prior to that I changed out the spark plug and cycled the key switch 3-4 times (to attempt to build fuel pressure) before turning the key to the start position. Neither of those options worked although the cycling of the fuel pump seemed to make it sound like it wanted to start. I was always told not to use the accelerator to attempt to start a fuel injected vehicle. But since I was ice fishing, I did not want to be stranded on the lake, so I tried it and as soon as I started to push the accelerator it fired right up.

Once I turn it off, I can start it right back up again. However, if I leave it sit for a few minutes I have to use the accelerator to get it to start. One point of note, when I replaced the spark plug the plug was still bright white, which has me thinking that I am running lean as the old plug was a light tan color.

So, I am inclined to think it is the fuel pump, but I am not sure. And since a replacement pump runs close to $400, I would like to make sure I am fixing the right thing. I see the service manual has a way to test the pump and I will try that today.

Any practical experience and advice would be appreciated.

d1
 

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Take a look at this thread:

 

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Discussion Starter #4
A fuel pressure tester is a nice thing to have before you buy a $400 pump. (Or any pump really) You can borrow one from Auto parts places for free too.
Does anyone have a part number/description for the fitting that can attach to the Schrader valve on the fuel rail. The guys at Napa had no idea what I was talking about and they would not let me open one of the fuel pressure test kits to see if it had one that would work.
 

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Does anyone have a part number/description for the fitting that can attach to the Schrader valve on the fuel rail. The guys at Napa had no idea what I was talking about and they would not let me open one of the fuel pressure test kits to see if it had one that would work.
I don't think mine even had a Schrader valve (2014 800) If you do I'm pretty sure that one will fit in the kit. In my experience there are 2 sizes, the large one on the hose and then there is the little adapter fitting for the smaller size. This kit?

Do you have an O'riely's or Autozone around? They will loan out kits with a credit card. Or Harbor Freight, better price and a good return policy.
 

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Discussion Starter #10
I don't think mine even had a Schrader valve (2014 800) If you do I'm pretty sure that one will fit in the kit. In my experience there are 2 sizes, the large one on the hose and then there is the little adapter fitting for the smaller size. This kit?

Do you have an O'riely's or Autozone around? They will loan out kits with a credit card. Or Harbor Freight, better price and a good return policy.
Napa did not have that in stock. I went to O'Reillys and picked up a Bosch 7818 kit. Hopefully, it will work as it's a 2 hour round trip every time I have to go get parts.
 

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Napa did not have that in stock. I went to O'Reillys and picked up a Bosch 7818 kit. Hopefully, it will work as it's a 2 hour round trip every time I have to go get parts.
Yikes, 2 hrs?! I'm thinking Amazon is in your future. I hope that kit has that little brass adapter if the other doesn't fit
 

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Discussion Starter #12
Okay, finally got the tester hooked up. I connected it to the fuel rail valve. When I turn the key to prime the pump it jumps to 43 PSI (the bottom end of range per service manual) and then drops to 36 PSI. I am not clear if this is normal or which PSI reading I should be using to determine if fuel pump is good or not.

Also, should the reading on the gauge stay constant or fluctuate when the motor is running? Please see the video links below of the fuel pump prime, the fuel pressure at idle (1300 rpm) and the fuel pressure at increased RPM ranges.

d1

 

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Hard starting when cold is common in the ProStar engines, symptom of tight valve clearances.

Pressure jumping around while running should be normal due to the injector opening and closing.
 

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If it does turn out to be the fuel pump, there are several quality aftermarket pumps available that are 1/4 the cost of OEM.
 

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Discussion Starter #15
If it does turn out to be the fuel pump, there are several quality aftermarket pumps available that are 1/4 the cost of OEM.
I have not found one yet that has the 43-48 PSI for this model. Unless it is okay to jump to 58 PSI???

Hard starting when cold is common in the ProStar engines, symptom of tight valve clearances.
Pressure jumping around while running should be normal due to the injector opening and closing.
Two things:
1) How would pushing the accelerator mitigate tight intake valve clearance, to get engine to start? If valve clearance was the issue shouldn't it be hard starting, below freezing temps, at all times???
2) With engine running and the pressure gauge attached, the needle dropped below 40 PSI, wouldn't this indicate a fuel pressure issue?
 

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Going a different route, my friend had an EFI atv and the sock on the fuel pump was just dirty enough that it was hard to start but would run well....for a while then it would die. Not sure if it is a separate part on this fuel pump but might be an easier fix.
 

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I have not found one yet that has the 43-48 PSI for this model. Unless it is okay to jump to 58 PSI???
The shop manual for the 2013-2016 570 RZR specs fuel pressure at 58 +/- 2 psi...
 

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1) How would pushing the accelerator mitigate tight intake valve clearance, to get engine to start? If valve clearance was the issue shouldn't it be hard starting, below freezing temps, at all times???
Not really sure of the answer. Dumping more fuel into an already too lean situation can help starting, I guess. I can tell you that valve clearance is the primary evil in hard cold starting / easy starting when warm situations. And it's an easy, inexpensive fix, according to those who have the skills. Lots of posts on here and Facebook 570 group attest to this condition; search "clearance" in this sub-forum.
 

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As my original post indicated, I have a 2012.
However, there is no difference in the engine between the 12 and the 13 model years, unless you count that POS plastic intake tube.
Looking at the parts, the 2012 and 2013 use the same pump, 2014 and up have a different p/n.
The actual fuel injector is the same p/n 2012 thru 2016.
IF it were me, I'd use the higher pressure aftermarket pump as a replacement, save a lot of $$. But I'd check the valve clearance first; I think checking it only involves taking off the valve cover and a set of feeler gauges; probably taking off belt cover so you can rotate the engine by hand. (Don't rotate it backwards!)

Have you pumped out your fuel tank to see if you have a lot of sediment? I'd pull it and flush it with fresh fuel before ordering a new pump. If the tank is contaminated with gunk/water/etc. you'll ruin a new pump quickly. That pump has an internal filter and is supposedly not serviceable.
 
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