Hyster S120XLS:
Backfiring

Hey so I need some advice in which direction to look first

back ground info:
I have a hyster S120XLS serial# D004D08510X I just replaced the water pump along with the thermostat and belt due to a leaking water pump got it all back together yesterday ran it and burped the coolant system I let it idle and warm up then I reved it to a higher rpms multiple times no problems what so ever everything was perfect then I let it sit over night was going to return it this morning

Problem:
today I started it up and let it idle for 5-7 minutes to warm it up before I took it back to the shipping department well as I backed it up to leave my shop it backfired coughed and died.... so I checked the fuel tank (its everyone's favorite prank to turn the lp tank off) every thing was good and I had just over 3/4 a tank of lp got back on the lift and started it, it fired right up no issue idled fine reved it up and it gave a series of tiny backfires I figured it was still cold since we were down to freezing last night so I idled it around the parking lot trying to let it warm up anytime I hit the throttle to fast it would back fire and cough brought it back to the shop all vacuum lines are attatched and the LP filter is clean now I am lost as where to start looking for the issue


any help would be greatly appreciated thank you in advance
  • Posted 13 Nov 2015 10:02
  • Discussion started by diesel_chick87
  • Oregon, United States
Showing items 1 - 4 of 4 results.
thank you guys for the advice after checking all of the suggested items I found one spark plug was burnt so after some more testing it ended up being a bad valve after doing compression tests(1 cyl. was 30% low) and leak down tests (same cylinder was at 80% leak down)
Thank you again for the advice
  • Posted 25 Feb 2016 08:26
  • Reply by diesel_chick87
  • Oregon, United States
water under the distributor cap would be the first check...
  • Posted 14 Nov 2015 11:03
  • Reply by edward_t
  • South Carolina, United States
"it's not rocket surgery"
ok thank you that was where I was thinking I needed to start
  • Posted 14 Nov 2015 02:00
  • Reply by diesel_chick87
  • Oregon, United States
You need to check the ignition. Plug wires, cap and rotor. Check the play in the rotor in the distributor, I have replaced a number of distributors due to wear.
  • Posted 14 Nov 2015 01:11
  • Reply by BREWSKI
  • Nebraska, United States

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