I have a Series1 580SL that has 6,3000 hours on the clock.It has always started like a champ.Lately when it is cold or even worse after it sits a couple of days it is hard to start.Engine spins fast it just will not light off.When using it throughout the day after the first start and engine is warm it starts fine.I know the filters are 1st. suspect.Are they a check valve somewhere in the fuel system that could be letting fuel leak back causing a hard start?Or worse could injector pump be getting weak?
probably a perished fuel line letting air into the system.common problem on internationals in the past nick..............
Alot of times the throttle shaft of the injection pump will leak due to hardened o-rings. This lets the fuel bleed back to the tank causing a hard cold start. I have seen units that did not show a leak with the engines lift pump leave a trail of fuel with a booster electric pump. The injection pump fixes are usually pretty easy if thats the problem.
69z - check your lift pump, that is where the check valve is - if you remove the inlet hose & hold your thumb over the fitting while you use hand primer, the pump should hold suction for a few seconds - if it does not hold suction, replace the pump - around $100.00 here If pump tests ok, check the fuel hose & the inline fuel filter - I've often seen small holes develop in them from rust. - they usually leak a little fuel when engine is stopped. :drinkup