I have recently noticed a ticking coming from the drivers side of my truck under the hood. Is this the inj. pump? And if so is this ticking a sign of something bad to coime in the future?<br><br>Thanks<br>Joe

 

Could be a couple of things. The first and most affordable would be the overflow valve. $55 through PDR. The second would be the lift pump. It can be had for around $150 through Cummins. <br>However, mine ticked from the day I got it until the day I sold it and I never had a Fuel pressure problem. Just a little ticking noise.

 

So you think it could be the mechnical lift pump or the overflow valve? Is there a way to test these items? I just don't want to have the pump fail when I need the truck.<br><br>Thanks<br>

 

A simple fuel pressure test would show if either items are bad. You should have about 20-22psi at the test port. I've seen pressures as high as 30psi on my last truck. Anything less than 17 psi and you'll want to take care of it.<br><br>As far as I know, these items don't usually have a catastophic failure. Generally, if the lift pump is going bad, it will start to leak.<br>If your overflow valve is the two part design, you can pull the overflow valve off the pump(make sure you don't drop that washer behind the pump) and take the top part off. Under that top part is a spring and a ball bearing. The spring should be .50 inches. You can stretch the spring back to .50 if it measures lower than it should, but that isn't a permanent fix. Replacing it would make a better choice. They are only $55 through PDR so it's not that big of a deal.<br>ALso, you might want to have a file handy. Sometimes there isn't enough clearance between the pump and the head to get the valve out so you might have to file some of the head casting to get it out.<br><br><br>If you pressure is low, check the overflow valve. If you get it replaced, and the pressure is still low, I would look at replacing the lift pump. <br><br>As I mentioned before, mine ticked like that for almost 3 years with no problems and good fuel pressure.

 

To check the overflow valve, just stuff a rag between block and the pump and unscrew the valve. The spring should be between 450 and 500 thousandths.<br>george