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Hazing at idle, hard to start, but timing seems correct

1K views 21 replies 5 participants last post by  Sheeps5304  
#1 ·
This is going to be long but I’m going to be as thorough as possible.

I had the short block rebuilt on my truck earlier this year. Just a standard .20 over pistons with an Hamilton efficiency cam and stock everything else. I put on a pdd towing port head, arp head studs, new Bosch 215 injectors and the reman injection pump when it went back together.

when it was first started the timing was off. The gear slipped. I lined everything back up it fired up and everything was good. Did my break in on the cam and then did the 400 or so mile break in on the rest of the engine. Changed oil on it and was backing it out of the carport truck died and wouldn’t start. It was smoking a lot just raw fuel so I assumed the timing slipped again.

I bought the dap adjustable gear with the key way to try to eliminate the timing slipping. Every time it went back together I used a new nut and washer. Cleaned everything. Torqued to spec but it wouldn’t hold. Anyway I also installed the raptor lift pump while I was at it. I also did the typical afc mods like the fender washers and taking a little off the afc foot. I set the pre boost screw to just barely touching the diaphragm and the starwheel to the stock location. I intended to dial that in later. The reman pump was just a stock replacement so I decided to do that while I waited on parts. When the parts arrive I lined everything up and put it at stock timing.

The truck was hard to start before the timing slipped it would turn over once and fire. Now it’s turning over 6 or 7 times before firing. When it does it idles fine but has a constant haze. Just smells like raw fuel. Rev it and it’s smoking like crazy. I double, triple, quadruple check the timing it all lines up. Marks on the crank and cam. The cam pin and the injection pump pin all line up and it’s still the same. I drove it down the road and back and just crap tons of smoke no power.

So I’m open to suggestions. I’m an idiot %99 of the time and don’t know if it’s something simple that I’m just over looking or what.
 
#2 ·
Smoke that burns your eyes typically means poor combustion.
Which could be a number of things, low compression, incorrect timing, low fuel pressure or bad IP.


What is the truck timed at? Should be 12-14.5* for that motor. Depending on the setup... a lot of guys run between 15-18* of timing.
Fuel pump builder should have told you where the pump is pinned.

Stock timing is great for, well stock trucks.
Once you add more fuel you want to advance timing earlier into injection event. More timing ---->> more time for fuel to burn.

Timing Usually doesn't slip out of the blue....

Generally when timing slips; it jumps timing quite a bit, causing the truck to not run. I wouldnt check timing first, but dont rule it out.

You could have set it wrong.

Are you using the timing pins for locating TDC? These are notoriously unreliable for finding precise TDC.
But....
Usually the pins work "good enough" for the engine to run . So I wouldn't expect this to be a problem.



Now always check the basics
Check fuel pressure. Should be At least 18-24 at idle, at least 15psi under load.
Check air handling system: air filter clean, nothing restricting the the intercooler (misplaced rag etc)
 
#3 ·
Smoke that burns your eyes typically means poor combustion.
Which could be a number of things, low compression, incorrect timing, low fuel pressure or bad IP.


What is the truck timed at? Should be 12-14.5* for that motor. Depending on the setup... a lot of guys run between 15-18* of timing.
Fuel pump builder should have told you where the pump is pinned.

Stock timing is great for, well stock trucks.
Once you add more fuel you want to advance timing earlier into injection event. More timing ---->> more time for fuel to burn.

Timing Usually doesn't slip out of the blue....

Generally when timing slips; it jumps timing quite a bit, causing the truck to not run. I wouldnt check timing first, but dont rule it out.

You could have set it wrong.

Are you using the timing pins for locating TDC? These are notoriously unreliable for finding precise TDC.
But....
Usually the pins work "good enough" for the engine to run . So I wouldn't expect this to be a problem.



Now always check the basics
Check fuel pressure. Should be At least 18-24 at idle, at least 15psi under load.
Check air handling system: air filter clean, nothing restricting the the intercooler (misplaced rag etc)
I used the pins for locating tdc. Every pin is aligned. The pump is from Pensacola diesel and was a stock pump so I’m assuming it’s 14 or 14.5. Fuel pressure is right around 30 lbs at idle. I tried raising and lowering fuel pressure to see if it had any change. It did not.
 
#5 ·
Ah I was waiting for someone to say it. Not being sarcastic at all. When I bought it I was thinking this is probably not a good idea. I had thought I seen people in Facebook groups saying not to buy parts from them. A lot of their parts are really cheap. I guess they are for a reason.
 
#7 ·
With an adjustable gear, assuming it is installed correctly, the timing cannot slip. I suggest you time the engine without using the pins. You don't know for sure where the one in the pump is set and the cam timing pin is adjustable so it could be way off too. There is the spill port method, which I do not know how to do and the plunger lift method. You will need a delivery valve removal tool and a dial indicator. Obviously you won't need the gear puller. Dodge Cummins w/P7100 Timing Tool Kit | Pure Diesel Power You will also have to determine the cpl of your p-pump P7100 Timing With Dial Indicator - Fuel - Mopar1973Man.Com LLC
 
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#8 ·
This is what I will do. Just buy the tools and time it using the dial indicator. What are the odds that the problem is the injection pump itself?
 
#10 ·
I was looking around on eBay last night and the p7100s that appear to be bad Chinese copy’s look an awful lot like the one I got from Pensacola. Just with a coat of black paint. When you really look at it it has such bad casting of the afc housing as well as the body itself.
 
#11 ·
If you do a little research you should be able to find pictures of what authentic Bosch data tags look like.

You also have to take into account " I also did the typical afc mods like the fender washers and taking a little off the afc foot. I set the pre boost screw to just barely touching the diaphragm and the starwheel to the stock location." All those things will affect p-pump operation.
 
#12 ·
My pump as absolutely no Bosch tags anywhere.

What was done to the afc shouldn’t have anything to do with starting and idle. The pre boost screw is barely touching the diaphragm. The starwheel is in the stock location. Removing material off the back of the afc foot should only affect travel and fueling when under boost. When I drove it it drove as if it was a timing problem. Not really a result of afc modification.
 
#17 ·
People in my area are on the pipe literally and figuratively. People want around 1000 for 160hp pumps missing parts around here.
 
#19 ·
....I bought the dap adjustable gear with the key way to try to eliminate the timing slipping. Every time it went back together I used a new nut and washer. Cleaned everything. Torqued to spec but it wouldn’t hold.
Is the woodruff key installed on the DAP gear? Please explain what you mean by: "Torqued to spec but it wouldn’t hold" . If that woodruff key is installed and all the bolts in the DAP gear are tight, the timing cannot slip.

I time using the plunger method. But that only works if you know which CPL pump you have. The plunger rise is different for different pumps and also is different for some modified pumps. Please keep us informed.
 
#20 ·
Is the woodruff key installed on the DAP gear? Please explain what you mean by: "Torqued to spec but it wouldn’t hold" . If that woodruff key is installed and all the bolts in the DAP gear are tight, the timing cannot slip.
I was referring to the stock gear when I said I torqued it to spec and slipped not the adjustable gear. Yes the key is in the adjustable gear.