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    1. · Registered
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      If you are going for another 300,000 miles then you should look at this as restoring the engine to like new condition. While I had the pan off to reseal it I would surely plastigage the bearings. They will probably be good to go but now is the time to find out.


      I'd strongly consider an new oil pump. It's $78 on Rock Auto. With the engine out it would be simple to replace. With the engine in it would be (explicative deleted) difficult.

      Something to consider would be an additional block heater on the other side of the engine from the factory heater. Makes warming the engine much faster if that is a consideration.


      I think head studs for a nearly stock engine are a waste of money. The latest head bolts are plenty good enough. If you are set on studs then have a look at this video:


      I would have your stock heads checked carefully by a shop and keep them if they have no problems. The valves should be examined at the same time. It probably wouldn't need a valve job but now is the time to find out.

      Plan on removing a lot of carbon from various places. This stuff works:


      I'd have to be really strapped for cash not to replace the CP4 with a CP3 at this time. I don't think I would do injectors now though, unless they have problems. It isn't that difficult to do them later in the truck and they aren't cheap.

      I would look at providing a bridge between the CP inlet to the fuel return line to the tank. This would allow fuel to circulate more freely. Your lift pump is capable of delivering about 7 times as much fuel as your engine can use under max power. Under normal power it is capable of about 30 times the fuel needed. What happens is that the lift pump develops pressure until it opens it's own internal relief valve. Most of the fuel just circulates around through the lift pump getting heated in the process. That isn't usually a good thing. Your truck comes from the factory with a fuel cooler for a good reason.

      By providing a return line from the CP inlet you will be allowing the fuel to circulate through the filters several times. This makes the system fully self priming. When you change the filters or run out of fuel it will start right up again if you let the lift pump run for a few seconds first.

      All of that circulation through the filters doesn't mean the fuel will be 30 times cleaner but it does mean it will be a little cleaner/dryer. The cost of this mod is a bit of hose, a couple of fittings, a check valve and a little brazing. Then the grossly oversized lift pump would at least be doing something other than heat the fuel. People often overlook the fact that the stock fuel setup uses vacuum to suck fuel from the tank to the CP. That means there can be no where for a lift pump to send excess fuel because if there were the CP would also draw from there without a lift pump.

      Here are some ideas on what it would take:

      check valve:
      Amazon.com : 1/2" check valve A check valve takes a little pressure to open so having it in the bridge hose would not only prevent the CP from drawing from the unfiltered return line if the lift pump failed but it would also hold a small amount of pressure at the CP inlet, for what ever use that might be.

      Hose:
      https://www.amazon.com/ACDelco-32106-Professional-Bulk-Reel/dp/B0013FXWSI/ref=sr_1_3?crid=2F6VN2Y8JX6EO&dchild=1&keywords=1/2+fuel+hose+diesel&qid=1633589852&sprefix=1/2"+fuel+hose,aps,280&sr=8-3 You will only need a few inches but what the heck.

      Hose barb fitting to braze onto CP inlet and return pipes:

      1/2" Hose barb tee (if you don't want to mess with brazing):

      When a bolt is torqued to yield a portion of the bolt stretches beyond it's elastic limit. That means it is permanently stretched. The result is a narrowing of the bolt where the stretch occurred. Some torque to yield bolts have a specification for how much that portion of the bolt can narrow before it is not useable. Another way to tell if a torque to yield bolt is still good is that a specification can be given for the minimum torque of the bolt. As the bolt stretches it becomes weaker. If it stretches too much it will be too weak to do the job and will never reach the specified torque. If it will reach the minimum specified torque then you can still use it. Mostly they don't trust us so they just say that the bolt isn't reusable. If you can see any narrowing of the bolt by using a straight edge against the side of the bolt then it is probably done for.

      A torque to yield specification typically goes like this:

      Install all bolts in the assembly finger tight. This ensures that all of the bolts will go in and that nothing is misaligned.
      Torque each bolt in the assembly to some low figure. Typically something like 15-25 ft-lb. This ensures that the part is fully seated and ready to have pressure applied.
      Torque each bolt to some high figure. This is typically 60-75 ft-lb. This sets the initial condition for torque to yield. All of the bolts are loaded fairly equally.
      Turn each bolt a specific angle. This is typically 60, 90 or 180 degrees. This may be the end of the sequence. If it is you should feel the bolt yield near the end of the turn.
      Turn each bolt an additional angle. This is typically the same as the previous angle but not always. You should definitely feel the bolt yield during this turn.

      The feel of a yield is that there will be more and more resistance until a certain point. At that point the resistance will stop increasing and may even drop off a little.

      Torque to yield produces more consistent results than a non-yielding torqueing. Not to be confused with non-yielding twerking.
       
    2. · Registered
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      9 Posts
      Discussion Starter · #15 ·
      If you are going for another 300,000 miles then you should look at this as restoring the engine to like new condition. While I had the pan off to reseal it I would surely plastigage the bearings. They will probably be good to go but now is the time to find out.


      I'd strongly consider an new oil pump. It's $78 on Rock Auto. With the engine out it would be simple to replace. With the engine in it would be (explicative deleted) difficult.

      Something to consider would be an additional block heater on the other side of the engine from the factory heater. Makes warming the engine much faster if that is a consideration.


      I think head studs for a nearly stock engine are a waste of money. The latest head bolts are plenty good enough. If you are set on studs then have a look at this video:


      I would have your stock heads checked carefully by a shop and keep them if they have no problems. The valves should be examined at the same time. It probably wouldn't need a valve job but now is the time to find out.

      Plan on removing a lot of carbon from various places. This stuff works:


      I'd have to be really strapped for cash not to replace the CP4 with a CP3 at this time. I don't think I would do injectors now though, unless they have problems. It isn't that difficult to do them later in the truck and they aren't cheap.

      I would look at providing a bridge between the CP inlet to the fuel return line to the tank. This would allow fuel to circulate more freely. Your lift pump is capable of delivering about 7 times as much fuel as your engine can use under max power. Under normal power it is capable of about 30 times the fuel needed. What happens is that the lift pump develops pressure until it opens it's own internal relief valve. Most of the fuel just circulates around through the lift pump getting heated in the process. That isn't usually a good thing. Your truck comes from the factory with a fuel cooler for a good reason.

      By providing a return line from the CP inlet you will be allowing the fuel to circulate through the filters several times. This makes the system fully self priming. When you change the filters or run out of fuel it will start right up again if you let the lift pump run for a few seconds first.

      All of that circulation through the filters doesn't mean the fuel will be 30 times cleaner but it does mean it will be a little cleaner/dryer. The cost of this mod is a bit of hose, a couple of fittings, a check valve and a little brazing. Then the grossly oversized lift pump would at least be doing something other than heat the fuel. People often overlook the fact that the stock fuel setup uses vacuum to suck fuel from the tank to the CP. That means there can be no where for a lift pump to send excess fuel because if there were the CP would also draw from there without a lift pump.

      Here are some ideas on what it would take:

      check valve:
      Amazon.com : 1/2" check valve A check valve takes a little pressure to open so having it in the bridge hose would not only prevent the CP from drawing from the unfiltered return line if the lift pump failed but it would also hold a small amount of pressure at the CP inlet, for what ever use that might be.

      Hose:
      https://www.amazon.com/ACDelco-32106-Professional-Bulk-Reel/dp/B0013FXWSI/ref=sr_1_3?crid=2F6VN2Y8JX6EO&dchild=1&keywords=1/2+fuel+hose+diesel&qid=1633589852&sprefix=1/2"+fuel+hose,aps,280&sr=8-3 You will only need a few inches but what the heck.

      Hose barb fitting to braze onto CP inlet and return pipes:

      1/2" Hose barb tee (if you don't want to mess with brazing):

      When a bolt is torqued to yield a portion of the bolt stretches beyond it's elastic limit. That means it is permanently stretched. The result is a narrowing of the bolt where the stretch occurred. Some torque to yield bolts have a specification for how much that portion of the bolt can narrow before it is not useable. Another way to tell if a torque to yield bolt is still good is that a specification can be given for the minimum torque of the bolt. As the bolt stretches it becomes weaker. If it stretches too much it will be too weak to do the job and will never reach the specified torque. If it will reach the minimum specified torque then you can still use it. Mostly they don't trust us so they just say that the bolt isn't reusable. If you can see any narrowing of the bolt by using a straight edge against the side of the bolt then it is probably done for.

      A torque to yield specification typically goes like this:

      Install all bolts in the assembly finger tight. This ensures that all of the bolts will go in and that nothing is misaligned.
      Torque each bolt in the assembly to some low figure. Typically something like 15-25 ft-lb. This ensures that the part is fully seated and ready to have pressure applied.
      Torque each bolt to some high figure. This is typically 60-75 ft-lb. This sets the initial condition for torque to yield. All of the bolts are loaded fairly equally.
      Turn each bolt a specific angle. This is typically 60, 90 or 180 degrees. This may be the end of the sequence. If it is you should feel the bolt yield near the end of the turn.
      Turn each bolt an additional angle. This is typically the same as the previous angle but not always. You should definitely feel the bolt yield during this turn.

      The feel of a yield is that there will be more and more resistance until a certain point. At that point the resistance will stop increasing and may even drop off a little.

      Torque to yield produces more consistent results than a non-yielding torqueing. Not to be confused with non-yielding twerking.
      Awesome amount of info, thank you! I went ahead and picked up the oil pump as suggested. Seems like a no-brainer considering the price and current level of access with the motor out. Luckily I have access to a bore gauge which I will be using to test clearances. And I use Hoppes for my guns anyway, so I happen to have a good amount of that on-hand for carbon removal.

      I decided to go with slightly higher-flowing injectors (S&S TorqueMasters), and if the turbo ever gives me problems, I'll replace it with one with a bit more power ceiling, so I did go ahead and opt for studs. Wish I would have seen the video you linked before purchase, but I got an incredible deal on the ARPs, so I'm not going to complain too much. Also it looks like as of about a month ago, the IFG studs are no longer available. Either way, that extra clamp I'll get will put my mind at ease if I ever do want to chase extra power.

      Thanks again for all the info!
       
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