Knocking Sound!

[Farmer Dill]

I have a 85 6.9l. This sound has only happened twice. While going down the high way it'll make this knocking sound but once I start driven at lower speeds it will go away. I'm stumped and would like to know what it is exactly

 

[93f250idi]

maybe an injector hanging open?

 

[smolkin]

Mine did this a little while ago...it was due to low oil level/ bad cdr and went away after adding 4 qts and a new cdr...what's your oil like? Are you low, or maybe it's due for a change?

 

[Farmer Dill]

I'm due for a oil change and wats the cdr?

 

[Dieselcrawler]

sorta like pcv valve on a gasser. it is located at the back of the intake behind the intake opening. looks like a tuna can.

 

[Farmer Dill]

Ok ya I know watt ur talkin bout now. How can I tell if it's that

 

[smolkin]

Easy way is if you're using an abnormally large amount of oil between changes. I was down to half capacity after a month. That is a bit much.

 

[icanfixall]

The cdr needs to be changed about every 7 to 10 thousand miles for best performance. When the break down they suck in the motor oil as fuel. Thats where you get higher exhaust temps from sometimes....

 

[Farmer Dill]

I use alot of oil nut I have a small leak. It takes about a quart a week

 

[Agnem]

If your injectors are aged, then change them out! Easiest way to eliminate them as your problem, and pick up some performance at the same time.

 

[RLDSL]

Yup, A slobbering injector on a diesel sounds exactly like a rod knock on a gasser

 

[Farmer Dill]

How much are moose injectors

 

[Agnem]

Not quite a grand. Salty in the IDI world, but cheap compared to everything else. Stock double B's on the other hand, about a third of that.

 

[RLDSL]

Not quite a grand. Salty in the IDI world, but cheap compared to everything else. Stock double B's on the other hand, about a third of that.

Pretty reasonable really, when you consider a set of rebuilt stock Bosch injectors for a German 6 cyl vehicle will generally run about that much. Stanadyne injection parts , we get used to getting off cheap.

 

[Farmer Dill]

Ok so I heard the sound again today and I took a look and this is what I found. One of the lines comin off the injection pump is drippin slowly so I think it needs tightened and also I took the oil filler cap off and smoke spewed out