Hey everyone. I have a e99 7.3 and its knocking pretty loud. Dont think its a compression issue because of no blow by. It gets louder as the engine warms up. Has a little knock when it starts right up but seems to be in tune with the rest of the engine noise so its hard to hear.there is no oil in the fuel and doesnt smoke on startup even in montana winter. But if i shut the truck off when its hot and come back out 5 minutes later the truck takes a little longer to crank (maybe like 4-5 seconds). Did a injector buzz test and they sounded good and also checked icp while at idle i was getting 500 psi. Have not done fuel pressure check but will be doing that this weekend. Could this be bad injector o rings? Im also pulling of the VC and replacing all o rings and torque em down. This is what it what it sounds like. Any tips would be helpful. And also whats the torque spec on injectors in ft-lbs

 

When my e99 did that I replaced the 8 injector and added FRX from riffraff. Problem solved, not sure if that's your problem but it fixed mine. I could hear it after driving and let it idle. Was louder then, then when first started cold.

 

Did u replace that #8 injector with a long lead injector? And if so was it an AF or AE code?

 

No, just the standard ab with the fuel rail cross over from riffraff diesel. I also changed all the o-rings on the injectors on that side as well. Glow plugs as well. I just figured I was in there so why not.

 

Hi and welcome to the forum fellow e99 owner.

Couple of quick questions.

Can you give us an idea of the mods to your truck?

Have you changed your fuel filter? If so, did the filter look black? If not, try that first if the truck is new to you. A black filter could be a sign of bad o-rings or that it is really old. Additionally, a clogged filter will starve the engine which can cause knock. I have a friend whose truck was that way when he purchased it and that was probably the biggest contributor to premature injector failure.

Here is a link to test the injector o-rings for leakage: https://www.ford-trucks.com/forums/1...cody-test.html

I tried replacing the #8 injector and it made no difference with my truck. The only thing that did was getting the air out of the fuel with the Hutch mod.

The torque spec is in "INCH" pounds=120" lbs. and you will want to use a torque wrench that is rated in INCH pounds due to the fact that torque wrenches should not be used within 10-20% of their low end rating. So, 120" lbs=10' lbs, but that is within the 10-20% margin for all foot pound rated torque wrenches.

When torquing the injectors, consider doing it while the truck is at full operational temp. You'll more than likely get an additional 1/4 to 1/2 inch turn without exceeding the torque spec. It is a bit of insurance against a loose injector(s).

Also, you may want to torque your rocker bolts, if you decide to go in there. They can be a source of noise as well.

 

Yeah the mods include a 4 inch exhaust, billet TV double clutched transmission with a tugger shift kit. No chip. Pillar gauges with egt, boost, and tranny temp. And i did the glowplugs about 3 months ago. Oil is about 500 miles old and i use rotella t6. I replaced the fuel filter last week and no oil was in the filter.

I know the basics to the powerstroke motor. I am going to college for a heavy duty diesel mechanic but we focus mostly on cummins. Im more interested in powerstrokes and the heui system it runs on.

 

I can hear the "tink" with the knock in your video - like fingernails on the chalkboard to me. Definitely check how low the injector torque is before you snug 'em up. Below 50 in/lbs mean new O-rings for sure.

 

im just going to replace them all.

 

Tugly,
How do you check what the current torque is? Preset wench to 50 inch lbs.???
Thanks for your helpl
Oldboots

 

Yep, I start at 50 in/lbs. If it spins, I'm-a-yankin'.

When I wanted to learn where the torque was at when the knocking started and the IPR was climbing at idle - I bumped the setting 5 in/lbs at a time and re-checked. I've reached 75 in/lbs both times, so that's the number when things go South - 75 in/lbs or less gives a measurable internal oil leak and a more obvious injector knock. Well... at least it does on Stinky.

 

Where in Montana are you?
I have an inch/pound torque wrench and would be willing to help out.

 

Im in helena. But i just went down and bought a snap on in-lb torque wrench and ive got a buddy already helping. But thanks for the offer!

 

Are the dorman injector o-rings good?

 

Yeesh. I'm good quality all the way when it's that involved to clean up a fail. I get my O-rings from Riffraff diesel.

 

I'm with Rich. Just say no to Dormans.