Sometimes just have to carry a bit harder and be present when they fight so their feed turns into saving them and getting a kill.
Can improve your Hecarim build a bit too in order to carry harder. Consider building spirit visage or deadmans before getting cinder. The resists and higher HP will keep you alive better while CDR or deadman's passive helps do more damage before people get even stronger late game.
Also cinderhulk is pretty weak early game when your % bonus HP isnt that high yet when you get this first, and levels arent as high yet so the passive burn is weaker. I finish the jungle saber or blade when I can afford it, but leave it at that. Cinderhulk only as 4th or 5th item.
Usually
- Tri-force and tier 1 boots
- Ninja tabi & spirit visage or Merc + plate. Rarely both of the same resist unless the enemy comp justifies it
- The other tank item of plate or visage
- Finish cinderhulk item. % bonus HP is much larger now with 2 tank HP items
- Flex slot. Randuins, Sterak, Mallet, Banshee or GA
Even if you get in a bad spot with allies you can usually get away with all the speed buffs