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7.3 litre ih.

Ronsii

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Jun 26, 2011
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Western Washington
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s/e Heavy equipment operator
I think they're hydraulic.... pretty sure...

Also check the valvecover harness... they like to short and lose injectors
 

Ronsii

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Have you redlined it for at least 30 seconds? if that don't work put a stethoscope on and try to locate it. then it's pull the head time...
 

funwithfuel

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Mar 7, 2017
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Will county Illinois
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Mechanic
First , follow Ronsii's advice.

Pull your valve covers. Some have 3 piece rocker arms. Sometimes, in an overspeed, it will spit out the ball fulcrum. Sometimes it will deform the arm itself.
This is not common when used with an automatic, its almost always when in a manual trans application.
More common is the harness/ valve cover gasket issue.
Good luck
 

petepilot

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Joined
Jul 7, 2018
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2,168
Location
central shenandoah valley va,
First , follow Ronsii's advice.

Pull your valve covers. Some have 3 piece rocker arms. Sometimes, in an overspeed, it will spit out the ball fulcrum. Sometimes it will deform the arm itself.
This is not common when used with an automatic, its almost always when in a manual trans application.
More common is the harness/ valve cover gasket issue.
Good luck
thanks ,it is auto. showing 341.000 will dig into it further
 

kenh

Senior Member
Joined
Aug 12, 2010
Messages
264
Location
bonners ferry,id
My 7.3 makes a similar noise, but silent when coasting I think it is combustion created.
When new it imitated a rod knock at idle. But that went away after a few K.
Maybe a random noise generator in the ECM, no extra charge.
 

GregsHD

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Sep 26, 2014
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Mahood Falls, BC
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Self Employed HD Mechanic
I have seen the rocker pedestal bolts come loose, then break the bolts. I always check torque on rockers and injector hold downs anytime I've got the covers off a 7.3.

You are talking a powerjoke not an old IDI 7.3?
 

funwithfuel

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Mar 7, 2017
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Location
Will county Illinois
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Mechanic
Depending on when it was made and what updates it got. The injection strategy is pre, and main injection. Pre injection was introduced to quiet the loud operation of the DI 7.3
Later they introduced post injection as well to reduce emissions and further reduce noise. It wouldn't come and go.
 

kenh

Senior Member
Joined
Aug 12, 2010
Messages
264
Location
bonners ferry,id
Mine is a 2001, 270 Hp. 6 spd.
The "rod knock" is a long time gone. If it flung a rod out I did not notice the event! LOL. The "lifter" noise has been with me for about 5 years, vexes me.
During that era lots of people were attempting to eliminated the "cackl"e I think It was called
 

walkerv

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Joined
Jan 21, 2016
Messages
1,125
Location
wingate nc
Mine is a 2001, 270 Hp. 6 spd.
The "rod knock" is a long time gone. If it flung a rod out I did not notice the event! LOL. The "lifter" noise has been with me for about 5 years, vexes me.
During that era lots of people were attempting to eliminated the "cackl"e I think It was called
One of the fixes that i think they only did in ford pickup trucks was the #8 injector was different then the rest i dont recall them being like that in ih medium duty trucks
 

kenh

Senior Member
Joined
Aug 12, 2010
Messages
264
Location
bonners ferry,id
Yep, is different, can't remember if they stayed with that or not.
One theory was 7and 8 being adjacent and together in the firing order and not fuel return was the cause of it.
Some folks claimed a cure buy installing a return in the rear of the head.
Do not remember the final verdict on that.
 
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