HELP! Two Bent Push Rods After Replacing Injectors

[FPollard]

TDR Members:

I have a 2006 Dodge Ram 2500 which IMHO is at about a medium build level. Roughly two months ago my truck started running very rough after a bad tank of fuel. Not able to correct the problem myself after draining the entire fuel system, replacing the fuel filter and lots of fuel injector cleaner, I took it into one of the best diesel mechanics in Flagstaff, AZ. After shutting down the cylinders individually, we determined that the #2 and #6 injectors were bad. I purchased 6x new +50 HP Bosch injectors and a FASS 150 gph 2x filtered lift pump which I had the mechanic install. Upon removing the valve cover, he found that the #6 injector was blown completely out of the hole and the retaining bolt holes needed to be re-tapped, which I thought was strange.

Three-Four weeks later and the addition of a Smarty TNT (w/ low-medium tune since I live at 7500ft. above sea level), the stock turbo bearing(s) blew out and the ECM threw a #6 cylinder misfire. I wasn't all that surprised with the turbo, since the addition of the massive aFe intercooler, the stock unit has been pushing 32-35 PSI for well over 2 years.

What was surprising, after installing the new turbo (aFe 58/76mm), the truck was still running rough. I remembered the #6 misfire and took it back to the mechanic to have a look. Upon inspection, he found that both #6 push rods were bent, with one broken as well.

Does anyone have any idea what could have caused this? My gut reaction is to blame the mechanic because it seems to be a very strange coincidence, but I don't want to accuse him without some sort of foundation.

Thank you in advance for any advice or assistance you can provide.

Frank

 

[NIsaacs]

TDR Members:

Upon removing the valve cover, he found that the #6 injector was blown completely out of the hole and the retaining bolt holes needed to be re-tapped, which I thought was strange.

I wasn't all that surprised with the turbo, since the addition of the massive aFe intercooler, the stock unit has been pushing 32-35 PSI for well over 2 years.

Upon inspection, he found that both #6 push rods were bent, with one broken as well.



Frank

If the injector was blown out you would have had more than just a rough running truck, the blow by would have been off the charts and the compression leak would have made enough noise to wake the dead.

32-35 psi for your turbo is not excessive, more than likely metal debris from #6 blew into the turbo causing the failure.

Bent or broken push rods usually mean valve to piston contact, possibly causing major damage. I would say the head needs to come off.

Nick

 

[CKelley1]

what he said is impossible. there is no way the injector can get loose enough to go anywhere without draining the rail and instantly kill the engine. I agree with nick but before you pull the head, this mechanic is so bad I would do some more looking. the ecm code is telling you that the #6 injector has a cracked crystal solenoid, if those were really new injectors then he has over tightened the nuts on the wire lugs cracking the crystal. get a ohm meter and check all of them, I bet all will read 0.5 ohms except #6 and it will be well above 1 ohm. next get a inch pound torque wrench and loosen all 6 injectors and see where it breaks at. I think it is 14 inch pounds. also the #6 is very hard to see, if he got the bridge on one valve and the other side on something else then it will cause a miss and bend the push rod.

 

[Joseph Donnelly]

Good advice above. Spec on injector hold down bolts is 89 inch pounds; even 75-80 is enough but much more than 89 and you will break bolts or strip threads; they are little guys, M6 x 1.0 thread. Connecting tube nut spec is 37 ft-lb and it could also have been tightened improperly (too much), distorting the injector body, or too loose, allowing a high pressure fuel leak into the return line.

 

[fox]

If the injector was blown out of the hole, it would of quit instantly as said above. But it could lodged between the valve cover and a moving valve to break/bend pushrods.

 

[cerberusiam]

Did the engine run and sound good after the new injector install?

Was the old injector really blown out of the hole or just the top blown off? Did the top show any damage?

Were new cross over tubes used with new injectors?

Does the current injector show any damage?

Did you hear any major knocks or noises when the engine started running bad with old injectors or new injectors?


The turbo is a lot tougher than that, if it blew something induced it. Either some massive rpm surge or FOD to cause a failure. Either the head has to come off or a boroscope used in that cylinder to check for damage. It is possible you have a floating seat that has cause the broke push rod issue and possible the previous injector damage.

If the complete injector came out of the injctor bore the truck would have dies immediately with LOUD obvious noises. It is entirely possible the injector failed, hydrolocked the cylinder and blew the top off the injector but you would still have had an obvious indication with a loud knock. It is possible on te back cylinder the push rods were not seated completely when it was started but running it for any length of time would have shown as a miss.

If the new injectors were installed and the truck ran good for hours\days\weeks it is probably a vlavel seat and\or valve failure.

 

[AH64ID]

32 psi is stock on your 06, and 32-35 is not excessive.

What lead you to the AFE turbo? When it was first released the compressor map was on the AFE website, and that turbo wouldn't support stock boost levels/flow, let alone the 40psi it comes at. Since then the compressor map has been removed, little strange if you ask me. It is also a smaller wheel, which with proper design can be fine, but it's a decent about smaller.

What kind of EGTs were you seeing? A low-mid level TNT tune with 50hp nozzles is a lot more fuel than the stock turbo, or the new one, can cool. At 7500 feet I could easily see EGTs getting pretty hot and doing valve seat damage.

 

[FPollard]

I don't know exactly what happened to the #6 injector, I didn't look at it before I sent the cores back. All I know is that one of the mounting hole HAD to be re-taped and the other was done for good measure.

 

[FPollard]

What lead you to the AFE turbo? When it was first released the compressor map was on the AFE website, and that turbo wouldn't support stock boost levels/flow, let alone the 40psi it comes at. Since then the compressor map has been removed, little strange if you ask me. It is also a smaller wheel, which with proper design can be fine, but it's a decent about smaller.

What kind of EGTs were you seeing? A low-mid level TNT tune with 50hp nozzles is a lot more fuel than the stock turbo, or the new one, can cool. At 7500 feet I could easily see EGTs getting pretty hot and doing valve seat damage.

I chose the aFe part because, from what I was able to gather' it was supposed to be a direct replacement with faster spool times, a slight performance gain and some additional cooling. I bought the turbo on Amazon.com, so if it doesn't work well, I will send it back and try something else, any suggestions?

Ever since I installed the massive aFe intercooler, my EGT's have never exceeded 1400 degrees.

 

[AH64ID]

1400 deg with stock timing is normal and acceptable, 1400 with the added timing of a smarty is asking for issues.

The stock turbo and intercooler are matched quite well, the most I have ever seen (even with my slightly larger turbo) is about 35 over ambient, meaning that of you were to make the air the same as ambient it would be good for about 50 deg drop in EGTs.

What tune is your smarty on?

Do you tow?

What mods have you done to the trans?