[John3311351]

Hi everyone
My bike is a TRX500 fped 2013
It stopped suddenly last week and would not start again as there was no spark I tested regulator/rectifier and found a rubbed wire on a little box beside the main rectifier (not sure what that is) so solid in a new splice of wire and resealed I now have spark and checked injector and it's also firing fuel but still no start
Not sure what could be wrong so any ideas would be welcome

 

[SamUK]

Do you get any flashes showing on the display? Have you checked voltages to and from reg/rec?

If you've got fuel and spark you should have fire!

Your missing something, quite possibly a silly/little thing that youve missed. I assume the timing is correct??

 

[John3311351]

Have only checked resistance readings to the regulator and alternator everything seems to be fairly normal can't really check voltage until I get her started and can't understand what I'm missing as well
I'm beginning to wonder if it's an aftermarket fuel pump that was put in six months ago even though it's cutting out after about 4 seconds I have no way of testing what pressure is getting too

 

[John3311351]

And there's nothing flashing on the display not sure about how to check timing as the bike was running fine until it just stopped can they just go out of timing like that

 

[SamUK]

If your doubting a fuel pump, odds on is it could well be! Always go with your first instinct, it's usually the right choice!

Timing can just go out yes, it depends on circumstances though... Mainly abuse and lack of maintenance!

Edit: I would replace the fuel filter and fuel line then try again. If no success I would source a good used fuel pump from PSN (powersportsnation) or of course a new OEM item. Depends on your budget.

 

[John3311351]

Hi sam I'm not far from you here in Ireland didn't see a fuel pump on power sportsnation problem with American companies here is delivery time
Going to put a new fuel pump in and filter even though I hate throwing parts at a problem instead of diagnosing it
Trying to get them fuel lines off is a bit of a nightmare is there a special tool for doing them

 

[shadetree]

if its getting spark ?, and getting fuel to the throttle body ?, then the only thing left to keep it from starting is not enough compression ?, or the timing is off ?. may have a bent valve ?. do a compression test.

 

[misterclean59]

I put fuel in a small hand held pump and then pump fuel into the throat of the throttle body. This should help determine whether it is a fuel problem or not.

 

[Jeepwm69]

Yep, shot of gas or starter fluid in the intake. If it fires, you have fuel pump issues. If it doesn't, you have a spark or compression issue.

These EFI machines have a bunch of electronic crap built in that will cut spark, so try a shot of fuel in the intake and if it doesn't fire off we'll troubleshoot further.

 

[John3311351]

Looks like I have a fuel pressure problem when I pulled the pump out today I found the little o'ring at the top had split I don't think that pump came with o'ring so I used one from a kit which was possibly a bit light. think I'll have a look for a full o'ring kit as one of the bigger ones seems to be stretched as well

 

[SamUK]

Hi sam I'm not far from you here in Ireland didn't see a fuel pump on power sportsnation problem with American companies here is delivery time
Going to put a new fuel pump in and filter even though I hate throwing parts at a problem instead of diagnosing it
Trying to get them fuel lines off is a bit of a nightmare is there a special tool for doing them

Hi John. Yes we're not far away at all are we!

For decent aftermarket parts you could try 'quadbikeswales.com', based in South Wales (UK). Very helpful folks and shipping is always within a few days if they have things in stock.

 

[SamUK]

if its getting spark ?, and getting fuel to the throttle body ?, then the only thing left to keep it from starting is not enough compression ?, or the timing is off ?. may have a bent valve ?. do a compression test.

As shadetree has said (he's old and knows better haha) timing could be out. A compression test is a very wise option also.

If you don't have a compression tester you can get a decent one from eBay for less than €20, PM me and I'll send you the link

 

[John3311351]

Shadytree might be old but he is right the first thing I checked was the compression had nearly 130 PSI which I think should be ok
Ordered o-ring kit and filter off of eBay UK last night hopefully parts will be here in a couple of days and I will check out the crowd in South Wales

 

[misterclean59]

We have ethanol here is the USA do you? Ethanol will swell o rings so quickly in ethanol that sometimes you can't get them installed quick enough before they swell to big to fit.

 

[John3311351]

We have ethanol here as well
Love to get my hands on the guy who came up with that idea after nearly burning up a couple of chainsaws
I would have thought most o'rings would be tolerant of ethanol by now. But that might be just wishful thinking

 

[LedFTed]

probable related to the professor, that helped sell obama-care[healthcare], then bragged about how he helped put one over on the people..
sponsored by big business, and parts salesmen, on either side of the pond..

 

[John3311351]

Funny Ted but you could be right
Another trick on them o'rings when they swell up is to wash them with some washing up liquid and leave them in the freezer for a while they will come back to size