Author Topic: SRX400 woes (still)!  (Read 1408 times)

mini-thumper

  • Posts: 921
SRX400 woes (still)!
« on: November 21, 2006, 01:31:57 PM »
Some of you may remember that I bought an SRX400 with strange running problems - it still continues!

From starting won't pull above 35mph for the first five miles, then as if a switch has been flicked runs fine. As soon as you turn the motor off its back to square one, and 35mph for the next five miles. Have had carbs off and they seemed OK, no crud or anything sticking. Next changed the CDI unit, again no difference, and just this Sunday borrowed ignition coil from SteveH and that made no difference either. I do have a replacement alternator which will be changed next, but before I tackle that it occured to me that it might not be electrical after all. My reasoning being; the SRX is a single cylinder and surely if there was a very weak spark it would either work or not. As it seems very willing to start then might it be some other quarter playing up! This then really only leaves the fuel, and possibly the fuel tap. I noticed that mine has a new fuel tap, and what with it being reliant upon inlet pressure to work properly, could this be the culprit? Have any other SRX owners had trouble with the fuel tap that might have exhibited similar symptoms?

Then there is the possibility that the Japanese only models 50mph light might be the source, (mine has been disconnected), again any one have any experience of this?

It sort of reminds me of a friend who could never get his VW camper van running after he put a new petrol tank on it. Ran fine for a few miles and then ran like c**p, after stopping same again, fine for few miles then c**p. Turns out a label had falling inside the tank and was being sucked over the fuel outlet by the fuel pump, as soon as he stopped it floated about and let fuel back into the carb. Only by chance did he find the problem, and a long grab pulled the label out.

Any thought or solutions to my SRX problem greatfully received......

BB 

andy230

  • Posts: 1322
Re: SRX400 woes (still)!
« Reply #1 on: November 21, 2006, 02:00:04 PM »
Hi Boyd!


I do have a replacement alternator which will be changed next, but before I tackle that it occured to me that it might not be electrical after all.

I'd try this.  Just change the stator.  Sounds exactly like the problem I had on my 600, turned out to be the stator.  easy to change if its still on the engine cover....

As it seems very willing to start then might it be some other quarter playing up!

Aye, possibly, but it could be the advance curve going wonky- ie. still gets a spark, just not at the right time...  And mine cleared once it got warm...


I noticed that mine has a new fuel tap, and what with it being reliant upon inlet pressure to work properly, could this be the culprit? Have any other SRX owners had trouble with the fuel tap that might have exhibited similar symptoms?

Put it onto "prime"- this bypasses the vacuum function.  And make sure the vacuum hose isn't leaking.  You could run the 2 hoses straight from the tank into a T piece and stright into the carbs.  (but woe betide the man who hass to turn his fuel off in a hurry under these circumstances!!)

Good luck mate

a

peterj

  • Guest
Re: SRX400 woes (still)!
« Reply #2 on: November 21, 2006, 10:15:56 PM »
If the stator swap doesn't work, a couple of other thoughts:

side stand switch playing up (if you have one)

kill switch likewise

both of the above known to cause intermittant running problems and should be easy to eliminate

did you have a close look for debris in the connecting pipe between the primary and secondary carb?

sticky slide in the secondary carb

as you suggest, leaky vacuum tap (my 600 had a rotten vacuum pipe, didn't cause a problem until I pulled it off though)

really dirty fuel filter in the tank - does switching between main and reserve make any difference?

My 600 has had a blown bulb in the "speed" light since a regulator "incident" a couple of years ago. This hasn't affected running at all.

Good luck and hopefully it's the stator (if it is it's probably in the pickup).

mini-thumper

  • Posts: 921
Re: SRX400 woes (still)!
« Reply #3 on: November 22, 2006, 08:31:42 AM »
Cheers for the help lads! Hopefully this weekend will see some positive results...............

BB

bullet350

  • Guest
Re: SRX400 woes (still)!
« Reply #4 on: November 22, 2006, 11:50:19 AM »
i second the fuel tap suggestion. they have crappy little ruber diaphragms inside if its sticky it may take a while for the vacume to pull it fully open. is it me or are they more trouble than they're worth?
  bullet350

andy230

  • Posts: 1322
Re: SRX400 woes (still)!
« Reply #5 on: November 22, 2006, 01:54:16 PM »
i second the fuel tap suggestion. they have crappy little ruber diaphragms inside if its sticky it may take a while for the vacume to pull it fully open. is it me or are they more trouble than they're worth?
  bullet350

Yeah agreed, but they're easily bypassed by turning them to the "prime" setting...

a