Persisting Hard Cold Start, Hazing and High Blow By
 

Hi y'all. I'm nearing at end of my wits and don't want to start "throwing parts at it unit it's fixed"....

My truck in question is in my signature with mod details.

I have hard cold start and what seem like excess blow by and hazing while accelerating or going uphill.

1) Cold Start
After sitting for a while, like overnight at minimum, longer cranking than normal even with some throttle and >70*F ambient temp. Usually maybe 3-5 seconds worth of cranking. It will make noticeable shake like one cylinder start to fire, then two shakes like two cylinders fired, then 3, then 4, etc then finally run on its own without the starter, immediately followed with white/gray smoke coming out of tailpipe. Then it immediately clear up and runs perfectly and will restart immediately just fine for rest of the day. The colder temp, the longer cranking and more shaking and white/gray smoke. I manually lift the fuel shut down solenoid to "ON" and prime the lift pump with no difference on how it start. My fuel hoses are clear and there's no visible air bubbles when pumping the lift pump.

2) Hazing
Anytime I accelerate or going uphill there's hazing out of tailpipe, no matter what, even when I stop any pressure to AFC with AFC LIVE (both knobs turned all way shut). Cruising on flat ground it run clean but as soon as I go up a hill or accelerate there's haze, always.

3) Blow By
I am running basically 3 crank case breathers right now. Two dual valve cover crankcase vents and stock tappet cover vent. The main reason I installed two dual valve covers to reduce/stop motor oil loss through blow by. Cold or hot it make enough blow by to make it look like my truck is either on fire or boiling coolant like if it's overheating. Driving empty motor oil loss is relatively minimum but there's noticeable oil loss after towing. I think my oil loss can be nearly eliminated if I block off tappet cover's vent though.

I'm struggling to determine are there one or multiple problems with my 12v Cummins??? I used borescope to look at Pistons when I install 5x14 injectors and they looked fine although my borescope isn't top notch to get good video quality. Even with AFC LIVE it's spooling still suck (I think). my friend said the blow by smell like burnt oil.

At this point I think 3 possible problems;
1) Turbo
Excess blow by from turbo through oil drain and cause poor spooling and hazing? But this don't explain the hard cold start
2) Injection Pump
On its way out? But don't explain the excess blow by? Or could it?
3) bad/worn cylinder(s)/piston(s)/rings
I think this is the most possible problem but not sure how it can cause my hazing and my oil consumption isn't that ridiculous high and there's no blue smoke.

Help??? How, where do I start next to get this diagnosed and fixed? :doh:

Timing and head gasket comes to mind.

Air leak in your fuel system or a weak lift pump

I would tend to agree...either that or the worst case the engine is hosed.

Those would cause blow by and hazing?

Chris

This is your main problem. Extra engine vents do not fix blow-by.

no, but crappy fuel delivery causes all sorts of starting and drivability problems. if trying to diagnose around a not yet blown up engine ide start with fuel. then probably a compression test to confirm your worst fears.

did you know if you plug them all the engine will whistle at idle.... lmao

He says in his post that he has no air bubbles in clear fuel lines...In my experience any air leaks would make bubbles until it purges through the pump and overflow valve.

Chris

not if its draining back. like a bad ofv or something fun like that. if he is priming the injection pump after a long overnight sit and then it runs great because its not sitting long enough to pull the fuel from the pump then this could very easily be an issue.

I left a piece of shop towel in the blow by tube after an unrelated repair... Not recommended! I had to replace tappet cover gasket because of that. Lol :bang

I'll go ask my friend to start it while I'm under it to watch fuel lines for air bubbles.

Stock and 7mm DVs, still hard cold start... Where else can I check on my fuel system?

bubbles will typically make it run like absolute hell all the time and not every really straighten out. if the system is however loosing prime while it sits after the injection pump you can drain the fuel from the system and have a tough time starting it in the morning or after a long sit.

That's right. It was to help crankcase blow by to vent better and to keep oil in. They did helped a lot for sure cuz I no longer have oily tailgate and or oil on front of the trailer.

On other hand, no coolant in oil and no coolant loss at all.

I'll try find time sometime soon to verify its timing is still at 16* and get some tools to do the compression test. Beside % difference between cylinders, how low is too low though?

EDIT: it have 302,xxx miles on it.

I just took 3 videos.

Cold start after sitting since last Saturday.


Blow by after idling for ~10 minute after the cold start in the previous video.

Blow by after towing.

If it's hard to start after its been sitting then you are losing prime. I fought that problem at various times with my truck when I had the stock mechanical pump. Once I switched to the electric pump I can leave the truck sitting for days and it starts the same as if it had just run an hour ago. It should start the same regardless of how long it's been left sitting if everything is as it should be.

Those batteries sound weak or your connections are weak. That's definitely not helping the cold start manners at all. Mechanical lift pumps like a little more rpm to start cleanly.

I don't really feel the need to address the blow-by you know it's not good!

That do make sense. I'll check my batteries, cables and connections. FYI I'm deaf so it's not something I readily notice

Noticeable oil loss after towing. Retorque your head. Piers Harry advised me to do this and it cured my problem. I'll bet a lot of people don't know who Piers Harry is. Boost goes up, lifts head enough to pressurize crankcase and kicks out the oil.

No where have I seen anyone ask what is your fuel pressure? The OFV does double duty, it maintains pressure and is also a check valve when the engine isn't running that keeps the return fuel line from siphoning the IP dry. Have you ever had an oil analysis done? Nearly every high blow by thread has a BHAF installed. I wouldn't be surprised if it turns out your oil is full of dirt. Dirt is like sandpaper in the engine.