How long do Distributor Caps and Rotors Last????!

I have a 1969 Merc 500 #2629264.

I have noticed the a Rotor and Cap are very expensive to replace in these motors. How long do they last? Hours whys that is. I have not replace mine but I think I need to, owned for less than a year and not sure of maintenance done by previous owner. The motor will run great than after some long easy running or WOT, the motor will just die out than be a little bit tough to start. Then she wont run good at all at low Idle. Any suggestions or tips are great.

Thanks much!!!!

Re: How long do Distributor Caps and Rotors Last????!

You should get a couple hundred hours out to the rotor and cap. Yes, they are more pricey than regular automotive styles, because they need to have the seals against sparks, etc that are required for the engine bay.

Re: How long do Distributor Caps and Rotors Last????!

I highly doubt it's the cap and rotor,it would act up at any RPM if that was the case..Sounds like a fuel issue. Have you tried pumping the bulb as it is dying out ? The bulb could be bad as it has a check valve in it. Your fuel pump might need to be rebuilt,when was that last done? Cheap and easy to do. The gas today can play havoc with the diaphragm on the fuel pump.How about the carbs , when was the last time they were cleaned and gone over.

Re: How long do Distributor Caps and Rotors Last????!

I just rebuilt the fuel pump and carb and replaced all rubber for the fuel system. I was not smart enough to drain the fuel tank though and I think maybe some particle got through. So I recleaned the entire fuel system and recleaned the carbs. The only thing I am in doubt with is the primer bulb. How do I know if it is jammed with something? I have pump the bulb and cant really tell the difference. I do a 50:1 oil to fuel ratio with stabil added. She starts great but when she gets hot or driven hard she runs not so good, I have to raise the lever on the control box to idle the engine. Should I try a new pimer bulb??

Thanks for the feed back!