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Discussion Starter #1
Ive searched high and low and feel I may be at the point of analysis paralysis on this issue.

Background:
Project truck going on 9 years running. I drove the 94 6bt donor truck for a few months with no issues before the swap. This is what has been done to it that I can think of.
- Played with AFC and fuel plate in the pump before pulled. Drove it with these tweaks for several months before pulling drivetrain.
- Pulled engine and 2wd trans from donor truck.
- Removed Ppump from engine for cleaning and painting.
- Rebuilt NV4500 and converted to 4wd and reused original clutch intending to upgrade clutch prior to engine upgrades after I could drive it for a year or so.
- Reinstalled Ppump on engine after cleaning and painting.
- Installed engine and drivetrain into truck. Engine starts and runs fine and has for the past 8 years or so. I have just never drove it enough to know it doesnt have much power.
- It has produced white smoke for as long as I remember since installed in the truck.
- Being so long ago since it was in the donor truck, I do not recall if it smoked in the donor truck but it definitely had plenty of power.

Symptoms
- Starts normal and seems to idle normal. Never hesitates to fire right up unless it is pretty cold(below 45F or so).
- Maybe slight white smoke haze at idle with fairly heavy exhaust smell.
- White smoke and exhaust fumes begin to increase with free revving as rpms increase.
- At maybe 2,000-2,500 RPMs, she begins to sputter some and will not rev much past this.
- After its first drive on the road a few weeks ago, I was hardly able to manage roughly 35 mph in 5th gear with low RPMs and that was downhill. On flat ground, I might have hit ~30 mph.

Research I've done with possible causes
- Air/Water in fuel
- Lack of fuel/fuel presssure
- Coolant leaking into combustion chamber
- Worn/improperly tuned injectors
- Slipped/bad timing
- Bad cylinder/piston/rings causing low compression
- Improperly tuned injection pump
- Low boost/boost leak

Things I have tried
- I knew that the head gasket was blown on the passenger side when I did the swap. I was going to install a new head gasket when I upgraded head studs and heavier valve springs. Well I went ahead and did these upgrades along with a head gasket thinking that it might be the cause of my issues. No change
- While I had the shop working on decking the head and installing new HD valve springs, I had them pop test the injectors for me. This was done simultaneously with the head gasket repair so... No change
- I had installed an Airdog a long while back as well. I noticed that my fuel lines were cracked from sitting on the truck for so long. I replaced them from hoses from Parker Store and connectors from Airdog. No Change
- While I had the lines off of the truck, I replaced the fuel filter/drained the water separator. No change
- I couldnt get the fuel lines bled initially and installed a fuel pressure gauge. After getting it installed and priming the pump(or so I thought), I had maybe 2 PSI at the injection pump. I was not priming it correctly, however, and ended once I figured it out and got the lines bled, I had a steady pressure of 35 PSI at the injection pump. No change
- I tried messing with the AFC and fuel plate again. While I had high doubts that this would be it, especially at an idle/free rev, it was a quick and easy check. No change

Things I have not yet tried
- I have not tried to time it yet. I do not have the tools to do so just yet. I have the socket for the injection pump but do not have the DV holder tool, the adapter for the dial indicator, or the puller for the pump gear.
- I have not checked compression. I do not have the tools to do this either. Since I will need the tools for timing again in the future for performance tuning, I will buy them. If the timing is within spec, I will probably take it somewhere to have the compression checked instead of buying the tools.

I feel like this should be fairly easy to track down and that I may just be missing/overlooking something simple. It has become very frustrating as this is the only issue preventing me from driving this thing!

I will be ordering the timing tools in the next day or two and will give them a shot as soon as I can. If anyone has had any experience with similar issues, I would love to hear your thoughts.

thanks!
 

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OK, you've done quite a bit of the normal things that would cause problems. On the timing testing, if this is a P pump engine you don't need any special tools to check the stock timing. That is done by locking the cam gear in TDC position and using the little tool in the injection pump to check that the timing is correct. If when you reinstalled the pump you did not properly clean the pump shaft and gear the timing could have certainly slipped. Here's a good video on the process. https://www.youtube.com/watch?v=0fRcs_RBfWg White smoke is usually unburned fuel. When you changed to the AirDog did you change the overflow valve in the injection pump? Not sure that a stock valve is compatible with those electric pumps. The upgraded mechanical pump would have been more than enough without the expense of the electric. A compression test would definitely be in order. Also, is the turbo in good condition? Fuel and no boost makes a lot of smoke and poor power. What does the EGT gauge indicate? Member Nascarmark may have some more ideas as to whats gone wrong.
 

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Timing set to stock specs on the earlier 12 valve engines would spit and sputter when cold. A tsb came out from dodge to raise the timing above stock in colder regions to help cold start ability.
 

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Discussion Starter #4
I may have some more info on this finally. Work has me buried right now but I can see the light at the end of the tunnel and got to take a break to mess with the truck.

So after all that I ruled out and as I said my next steps were, I started to dig into the timing. I received the gear puller, dv socket, dv adapter, and dial indicator..... but I haven’t got to use them yet.

I started by pulling the cam gear timing pin(man that was a bitch itself) and then turned the engine to TDC, or so I thought. I watched the exhaust valve of #1 cylinder while turning the crank until it just starts to CLOSE. Per the instructions that came with the timing kit, this was supposed to get me close. So I contorted my hand back there to feel for the dimple in the cam gear: nothing. Bumped it bit by bit both ways until I could feel something: nothing. Finally just started turning the crank until I did feel something, which I did..... about a full turn and a half of the crank later. This can’t be right.

I figured I came back around two revolutions of the crank and jus went past it the first time so before I moved it again, I made a visible mark at 6:00 on the balancer. I then began to turn the crank again until I saw the exhaust valve of #1 cyl open and then begin to close. If I remember correctly, it didn’t do so until my mark was at about the 2:30 position. I do know for sure though that I did have to turn the crank from about the 2:30 position past the 6:00 position and back around to the 6:00 position where the dimple is in the back of the cam gear. What gives?

The crank gear is the only thing that is guaranteed good at this point. I could have swore and was 99% positive that I didn’t take this cam gear off of the cam when I pulled it from the donor truck(back in 2012) because I didn’t even take the head off of this one until last fall. I had the cover off of the timing case and the Ppump off of it for clean and paint, but I don’t recall messing with the cam on this engine.

Does any of this sound right? My biggest question is how the heck would it even run if THE CAM is that far out of time. And not to mention the pump timing. It’s hard to tell where it is. And it runs just fine at an idle and even to 1500 rpms or so.

I think I need to check a couple of things after thinking about it while typing this:
- check to see where #1 cyl is when the exhaust valve is closed. (As soon as I typed that, It didn’t sound right. TDC should be when the piston is at the very top of the exhaust(?) stroke so it would have to mean when it just stops closing and that would be TDC of the exhaust stroke? But I thought you wanted TDC of the compression stroke?)
- check to see if the pin on the pump matches up with the dimple of the cam gear. Just to be sure they don’t match.

I’d love to hear from those of you with more experience than myself about the timing of these engines.
 

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You need the #6 cylinder valves rocking which puts #1 on TDC compression, or as you have already made a mark with the #1 cylinder valves rocking just rotate the engine 1 turn.
With white smoke it with Diesel or Kerosene smell is a misfire/bad injection event. Poor boost or lack of will give a lot of black smoke unless you are also lacking fuel.
Cheers Steve
 

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Discussion Starter #6
You need the #6 cylinder valves rocking which puts #1 on TDC compression, or as you have already made a mark with the #1 cylinder valves rocking just rotate the engine 1 turn.
With white smoke it with Diesel or Kerosene smell is a misfire/bad injection event. Poor boost or lack of will give a lot of black smoke unless you are also lacking fuel.
Cheers Steve
Thanks for the reply Steve. So you mean when #6 cyl valves are closed and the rockers have movement?

My cam has to be in time with the crank or it would have been a bad day the first time I tried to start it I’m assuming. Is this a pretty safe assumption?


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By rocking I mean #6 exhaust is closing as #6 inlet is opening, you will see both valves moving. This places #1 at TDC compression stroke.

A mark on the front crank pulley will come to the same position for either 1 or 6 firing, just need to know which cylinder is actually on compression/firing..
As you have marked the pulley and #1 valves are easiest to access you just need to check both #1 valves have clearance and it is then on compression.
Cheers Steve
 

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Question. Why did you remove the cam gear locking pin? When locked into the back of the cam gear that guarantees you are at TDC. Now if the little tip is broken off you'd need a replacement pin. Before you break the pump gear loose you needed to verify that the pump was at stock timing with the little pin in the side of the pump. No special tools needed for that. If that pin doesn't align to the little part in the pump then your timing has slipped. Do you have the front cover off the engine? When in the TDC point, the single 0 and double 00 on the crank and cam gear should line up. The cam gear can't slip because it is key'd to the cam and heat shrunk in place. If one has ever been removed it could walk off the cam but not slip.
 

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To get to TDC the easy way, rotate engine by alternator nut and watch #6 cyl rockers. Once the #6 exhaust valve closes and the intake just starts to open (move down), you stop and now you know it is at TDC on #1 cyl. This is TDC, or as close to TDC as we need to be for doing the valve lash adjustments. Now check that both rocker arms on #1 cyl are loose. If not, check # 6 exhaust rocker and if it is loose at all, then your 360° out on the crank, so rotate the engine over by the alternator nut til the harmonic balancer turns a complete 360°. Another double check for TDC is if the exhaust valve on #1 cyl, #3 and lastly #5 and #1's Intake, #2 and #4 are all loose, your on TDC.

Mark the 12 o'clock (very top) of your harmonic damper for reference later.
 

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Discussion Starter #10
Question. Why did you remove the cam gear locking pin? When locked into the back of the cam gear that guarantees you are at TDC. Now if the little tip is broken off you'd need a replacement pin. Before you break the pump gear loose you needed to verify that the pump was at stock timing with the little pin in the side of the pump. No special tools needed for that. If that pin doesn't align to the little part in the pump then your timing has slipped. Do you have the front cover off the engine? When in the TDC point, the single 0 and double 00 on the crank and cam gear should line up. The cam gear can't slip because it is key'd to the cam and heat shrunk in place. If one has ever been removed it could walk off the cam but not slip.
I removed the cam timing pin because it is VERY tough to slide in and out of its cavity. So I instead just feel with my finger until it is very close and then will use the pin to be sure that it is locked in when I go to time it.

I have not moved the pump timing yet. I would be willing to bet that it is not very close to pin timed. At least that is my hope at this point.

I’m my long winded original post above, I stated that I had the pump off before for cleaning and paint when I swapped it from the donor truck and into this one. I had the cover off at one point as well to tab the KDP and replace the front main but from what I can remember, I am 99% sure that I did not remove the cam or cam gear from this motor.


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Discussion Starter #11
To get to TDC the easy way, rotate engine by alternator nut and watch #6 cyl rockers. Once the #6 exhaust valve closes and the intake just starts to open (move down), you stop and now you know it is at TDC on #1 cyl. This is TDC, or as close to TDC as we need to be for doing the valve lash adjustments. Now check that both rocker arms on #1 cyl are loose. If not, check # 6 exhaust rocker and if it is loose at all, then your 360° out on the crank, so rotate the engine over by the alternator nut til the harmonic balancer turns a complete 360°. Another double check for TDC is if the exhaust valve on #1 cyl, #3 and lastly #5 and #1's Intake, #2 and #4 are all loose, your on TDC.

Mark the 12 o'clock (very top) of your harmonic damper for reference later.
Thanks Nascarmark. That gives me some more reference to see where I’m at. Heading out now to give this another look. I’ll let you know what I can find.


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Discussion Starter #12
To get to TDC the easy way, rotate engine by alternator nut and watch #6 cyl rockers. Once the #6 exhaust valve closes and the intake just starts to open (move down), you stop and now you know it is at TDC on #1 cyl. This is TDC, or as close to TDC as we need to be for doing the valve lash adjustments. Now check that both rocker arms on #1 cyl are loose. If not, check # 6 exhaust rocker and if it is loose at all, then your 360° out on the crank, so rotate the engine over by the alternator nut til the harmonic balancer turns a complete 360°. Another double check for TDC is if the exhaust valve on #1 cyl, #3 and lastly #5 and #1's Intake, #2 and #4 are all loose, your on TDC.

Mark the 12 o'clock (very top) of your harmonic damper for reference later.
Ok, since the engine can only be turned counterclockwise which is opposite of the direction it runs, I did this in reverse since it was easiest from the top of the engine to turn by the alt nut and watch. So therefore, I waited until the intake valve JUST closes(coming up) and then checked where I was. Both rockers on #1 cyl are loose and both valves on #6 cyl are tight. I’m assuming this should be TDC for cyl #1?


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Ok, since the engine can only be turned counterclockwise which is opposite of the direction it runs, I did this in reverse since it was easiest from the top of the engine to turn by the alt nut and watch. So therefore, I waited until the intake valve JUST closes(coming up) and then checked where I was. Both rockers on #1 cyl are loose and both valves on #6 cyl are tight. I’m assuming this should be TDC for cyl #1?
The way Nascarmark described it helped a ton. Thinking of the alt pulley going in reverse helped too.

Well I’ve got mixed feeling about this. As far as I can tell, she is pin timed. I’ve got the dimple on the cam gear lined up very close by feel with the hole and the tab in the pump is showing and I can get the slot of the tool to engage it. I’m happy that I have something else ruled out but very confused as to where to go from here and what else it could be. I thought for sure timing was going to be the issue.

I am all ears as to what else it could be. At this point, I’m leaning towards the injection pump. I’m at a loss.
 

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If you're sure you have the engine at TDC, does the little pump tool easily engage the timing tab. If not, then you know the timing is off. The pin should slide in easily and engage the tab if all is correct. One thing I had asked was there any change in the injection pump overflow valve when you went to the Air Dog. If the old valve was weak, which can happen, you may be venting most of your fuel back to the tank. This may not show up as a loss of pressure at the input point.
 

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Unless you have a very large amount of air in fuel, it's rebuild time. Free reving means nothing....some of these inj pumps don't like no load fuel reving, but can run perfectly fine under load. Seeing as your inj pump breaks up on higher free rev but doesn't re-act properly under load.... at this point, I believe you have 3 options you should seriously take a look at....pull inj's to have inspected or pull inj pump to be rebuilt or pull both for total good base line.
 

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Discussion Starter #16
If you're sure you have the engine at TDC, does the little pump tool easily engage the timing tab. If not, then you know the timing is off. The pin should slide in easily and engage the tab if all is correct. One thing I had asked was there any change in the injection pump overflow valve when you went to the Air Dog. If the old valve was weak, which can happen, you may be venting most of your fuel back to the tank. This may not show up as a loss of pressure at the input point.
I am very positive of TDC as everything is lining up. My valves are as Nascarmark described, which was very close to the mark I had already made for TDC, which also has the dimple in the cam gear very close as well and also the tab of the pump is showing very close as well. One thing about this, I did not put the pin in the cam gear but It was very close by feeling. The tool for the pump did slide right in however.

I did not replace the overflow valve but I did buy one and have it sitting in the shop ready to go on. I didn’t think it would be a possibility but I am curious now that you bring it up again. The only reason I don’t think it will be the issue is because the white smoke happens very early on in the rev. With just a very little of rpms, the white smoke begins and the heavy exhaust fumes are apparent at an idle.


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Unless you have a very large amount of air in fuel, it's rebuild time. Free reving means nothing....some of these inj pumps don't like no load fuel reving, but can run perfectly fine under load. Seeing as your inj pump breaks up on higher free rev but doesn't re-act properly under load.... at this point, I believe you have 3 options you should seriously take a look at....pull inj's to have inspected or pull inj pump to be rebuilt or pull both for total good base line.
With the airdog and now it’s new supply lines, I don’t think there would be any air in the fuel, especially not enough to create these results. I replaced the supply lines to rule them out.

It does not run well at all under load either which points me to the pump in my opinion. As I mentioned on the original post, I couldn’t hit but 35 mph and that was downhill on a long stretch.

I had the injectors pop tested when I had the head off and had it in the shop and they supposedly all checked out good.

One thing worth mentioning is that this motor ran just fine before I pulled it but also worth mentioning is that it then sat for years with only periodic starts in between. It was never driven until recently. Always just started and revved a bit and putting around the property and never faster than 2nd gear.
 

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White smoke that burns your eyes and nose is normally caused by a fuel supply problem. If it ran fine in the original chassis and malfunctions in the new chassis then the usual new problem will be found in the new chassis.

The normal first check after changing the fuel filter and cleaning the lift pump filter screen (in a P-Pump equipped engine) would be the following:

Get a plastic gallon jug and put about a half gallon of fuel into it. Remove your supply and return lines and replace them with hoses long enough to be inserted into the jug. MAKE SURE THE SUCTION SIDE LINE IS NOT TOUCHING THE BOTTOM OF THE JUG. Start the truck and check the amount of fuel returning to the jug. At idle there should be a noticeable amount of flow. If the truck runs normally at this point I would then check to be sure the tank is vented; that the fuel pick up in the tank does not have an electric fuel pump attached; and that there is no gasoline filter screen remaining in the fuel tank. Old fuel mixed with residual gasoline and water could cause this problem.

Also make sure that your fuel shut off solenoid and "run" terminals are properly wired. There is a link in the stickys on proper wiring connections.
 

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Discussion Starter #19
White smoke that burns your eyes and nose is normally caused by a fuel supply problem. If it ran fine in the original chassis and malfunctions in the new chassis then the usual new problem will be found in the new chassis.

The normal first check after changing the fuel filter and cleaning the lift pump filter screen (in a P-Pump equipped engine) would be the following:

Get a plastic gallon jug and put about a half gallon of fuel into it. Remove your supply and return lines and replace them with hoses long enough to be inserted into the jug. MAKE SURE THE SUCTION SIDE LINE IS NOT TOUCHING THE BOTTOM OF THE JUG. Start the truck and check the amount of fuel returning to the jug. At idle there should be a noticeable amount of flow. If the truck runs normally at this point I would then check to be sure the tank is vented; that the fuel pick up in the tank does not have an electric fuel pump attached; and that there is no gasoline filter screen remaining in the fuel tank. Old fuel mixed with residual gasoline and water could cause this problem.

Also make sure that your fuel shut off solenoid and "run" terminals are properly wired. There is a link in the stickys on proper wiring connections.
I would agree that it has to be something in the new chassis.

I actually had the lift pump(Airdog) completely apart searching for the issue. I cleaned the screen in it(it seemed clean to begin with) and replaced the filter. Same results

About the tank being properly vented. What constitutes a properly vented tank? I would guess mine isn’t vented properly because when I remove the fill cap, I get air relieving out of it. I thought I had tested this with the cap removed but maybe I hadn’t. I will check this again and go through your schedule other checks as well. The tank I am using is an in bed transfer tank/toolbox combo. I would have thought that the cap was the vent. Is that possible?

My fuel shutoff should be wired correctly. It start, runs and shuts off with the key and I’ve got a pretty clean wiring panel for these circuits and other accessories. I will test again with the solenoid disconnected.
 

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Bob, I think the Air Dog fuel pump will make that testing method difficult. Not sure if an in bed transfer tank has a vented cap or not. You may have hit on an issue there. The word "transfer" indicates it's not designed as a primary fuel tank. Did you add a return line to it? If so, how far into the tank does that line go. Might crack the cap open and see if your problem changes.
 
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