can some one tell me what a heat cycle is, what it does, please tell me in dumb country boy, shade tree terms

 

It is just starting up and running the item up to operating tempurature and then shutting it off and allowing it to cool. If you drive to work and back you are doing 2 heat cycles a day just for that activity.

 

And what a fun activity it is to do 5 or 6 days a week for 35 years.
I'm ready for the golf course now.

 

so i have read a vp44 only has about 2000 cylcles true or not

 

The life of a vp44 has very little to do with the startup/shutdown cycles on an engine. I'm certainly no Bosch service technician, but I do know that the early electronics on them were much more susceptible to damage from heat than the more recent ones. That was one of the reasons I bought my FASS--I figured that if I had more fuel flow through the vp44 (ie, more coming back to the fuel tank via the return line), that it would help to cool down the vp44.

I know that there are many other things that influence the life of a vp44, but you just can't tie it to the number of start/stop cycles on the engine. Assuming good fuel, adequate fuel pressure from the lift pump, and no cooking of the pump's electronics, it should last a very long time. On the flip side, consider a truck in a cold northern climate that is forced to run on pure #1 diesel with very little lubricity to it, and a marginal lift pump that is only supplying 5psi on a good day. That vp44 wouldn't last nearly as long.

Mike

 

I think my brain only has a 2000 heat cycle life. I'm 5000 cycles into it now. What was I talking about?....

 

I can vouch that the vp44 has more than 2000 cycles in them. I've put that many on in the last 3 years that I've owned the truck. It has much more to do with heat and keeping a cool, ample supply of fuel to the injection pump...