Engine/Transmission (1994 - 1998) Knocking Sound

[drrhoades]

I had a slight knocking sound, kind of like a hollow loud knock before I got my timing adjusted. It was barely noticable at idle. After I got my timing bumped up to 18 deg it is very noticable and loud at idle. Once I put it in gear and get moving then it goes away but then I have a ticking sound kind of like valves. I am just wondering what this sound is? Also when they did the timing the new guy messed up and forgot to change the o-ring so I ended up driving an hour and having to go back because it was leaking fuel. When they took the delivary valve off the o-ring was in a couple of pieces. I took the o-ring pieces out myself and got everything that I could see. Would this contribute to the knocking sound. I would like to get this fixed as soon as possible because it is really annoying. I am going to poke around this weekend and check things.



Thanks in advance,



Doug

 

[drrhoades]

Any advice would be very helpful



Thanks

 

[Todd T]

check your transfer pump. when they get worn and start to wear out they tend to knock a bit. the spring gets weak and the rod starts to pound on the tappet

 

[drrhoades]

I think that I found the problem. The #6 injector nut is loose. What size is the nut?

 

[Andy Redmond]

19mm or a 3/4" sae wrench in a pinch



I second the lift pump as the tick. Cummins #'s lift pump. . 3936316, 3931059 (gaskets times 2).



Good luck

 

[drrhoades]

Thanks for the replies. On the seepage around the injector can I just loosen the injector nut that holds the injector in and retighten it or do I need to replace any o-rings to cure the leakage. It seems to be leaking between the nut and the injector body.



Thanks,

Doug

 

[Keith1]

just loosen and re-tighten