I had my intake and exhaust valves adjusted by my local shop and a couple of other things done, and the mechanic asked me about my delivery valve. I have no symptoms of a bad delivery valve, but what ARE the symptoms of a bad one? I have 335,000 on the truck and have never done anything to the delivery valve. What happens to them? Do they wear out?

 

I think your mechanic means Overflow Valve. Yes, they do weaken over time/mileage = slower throttle response and slightly reduced inj timing due to lower pressure. Search Overflow Valve.

 

Yes, that's probably what he said. Thanks.

 

Is replacing it something that I could do myself?

 

Yes, very easy. Order one from Larry B's and it is the banjo bolt that goes in the injector pump. It has washers and springs so you'll have to be very patient and not drop anything but you can handle it.

 

Great! Will do soon. Thanks.

 

Here's what it looks like...

 

I ordered one from Larry B and will put it on. Thanks!