6.4 developed a knock. Thoughts?
#16
Lots, they are keystone rings designed to seal up with higher pressures.
At idle, lots of blowby, under hard boost and fueling, they should seal up better than normal rings.
But in general, lots of blowby.
From what I gather, normal rings would have less blowby at idle, but wouldn't work as good holding pressure at high boost.
At idle, lots of blowby, under hard boost and fueling, they should seal up better than normal rings.
But in general, lots of blowby.
From what I gather, normal rings would have less blowby at idle, but wouldn't work as good holding pressure at high boost.
Didn't know that aspect about the rings...learn something new everyday! Thanks for the info!
#19
I took the truck to the Ford dealer today. I will keep you posted as to what they find out. Interestingly when I first started it the noise was not there, but by the time I made it to the shop it was tapping again. It seems to be more prevalent when warm, similar to the symptoms Tepot is having in another thread.
Hunter40
Hunter40
#20
Just a quick update on the problem. Tech is still trying to determine the problem. Today he found the fuel trim level high on cylinder 2 at 18. The rest were okay. Power balance test showed variances on cylinders 2,6, and 8 of -1,-1,and -2 respectively. Definitely something going on with that bank.
Since the balance test was not that far off I am hoping for just an injector, but I am usually not that lucky.
Next step is to pull driver side valve cover to inspect valve train and perform a manual compression test.
Hunter40
Since the balance test was not that far off I am hoping for just an injector, but I am usually not that lucky.
Next step is to pull driver side valve cover to inspect valve train and perform a manual compression test.
Hunter40
#21
#22
Good call Senix. Rockers are "severely worn" and need replacement. Tech was unable to get a good view of cylinder 2 with a bore scope, but service manager was not sure why.
Compression test in the morning to check condition of cylinders.
Hunter40
Compression test in the morning to check condition of cylinders.
Hunter40
#23
#24
Oil has been changed every 5,000 with T6 Rotella. The truck never idles and averages 43mph over its life. This just points to a poor design by Navistar in my opinion.
Hunter40
#25
#26
Compression was a little low in all cylinders. #2 was the worst at 250. However upon more inspection the tech found that the injector was hanging open and slightly scored the top of the piston. The #8 cylinder cross hatches are getting worn off too.
The tech recommends a complete engine to repir ti right but thought it would run for a while with just the new injector and rockers. Since I don't have $18,500 lying around for a new engine, that is the route I am planning to go.
Is this a good idea with thise compressions? I'm guessing the compressions will get better after new rockers. Should I address anything else with either cylinder 2 or 8?
#27
#28
The only thing i would add to that is the valve bridges, if the rockers where severely worn they almost always damage the valve bridges, there cheap and should be replaced while your in there.
#29
It's almost like you are working on my truck, Senix.
Compression was a little low in all cylinders. #2 was the worst at 250. However upon more inspection the tech found that the injector was hanging open and slightly scored the top of the piston. The #8 cylinder cross hatches are getting worn off too.
The tech recommends a complete engine to repir ti right but thought it would run for a while with just the new injector and rockers. Since I don't have $18,500 lying around for a new engine, that is the route I am planning to go.
Is this a good idea with thise compressions? I'm guessing the compressions will get better after new rockers. Should I address anything else with either cylinder 2 or 8?
Compression was a little low in all cylinders. #2 was the worst at 250. However upon more inspection the tech found that the injector was hanging open and slightly scored the top of the piston. The #8 cylinder cross hatches are getting worn off too.
The tech recommends a complete engine to repir ti right but thought it would run for a while with just the new injector and rockers. Since I don't have $18,500 lying around for a new engine, that is the route I am planning to go.
Is this a good idea with thise compressions? I'm guessing the compressions will get better after new rockers. Should I address anything else with either cylinder 2 or 8?
If you don't mind me being nosey, how much are they charging to replace the rockers, bridges, and the one injector? Hope it goes well for you!
Clint
#30