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Discussion Starter · #1 ·
Apologies for creating a new post but I didn't get any response from my original thread....
Mods, feel free to delete if needed but I need assistance badly!!
I'm away for work and get home in 2 days so hoping to have some advice on things to check by the time I get home.

Righto, head is on but I think I may have some other dramas.:mad:
Head studs installed.... brand new head installed to ARP torque specs with genuine standard gasket.
I did have a small issue where No2 2 Cyl exhaust push rod popped out of the rocker socket when adjusting valve clearances without me noticing and jammed up on the under side of the rocker arm and also side of the hole in the head that the push rod goes through. I didn't realize it was like that when manually cycling the crank and once I did notice, the push rod/rocker arm wouldn't move during manually trying to cycle the crank(had not tried to 12v crank at this stage). I ended up needing to use a pry bar to lever the back of the rocker arm up to open the valve and pop the push rod back in its home socket in the rocker arm.

I am able to manually wind the motor over and seems tight under compression but no untoward noises..... Im not sure 'how' tight its meant to be. The issue I have now is that is seems to really struggle to crank under ignition starting.

I'll explain the changes made whilst changing the head out and write off a few issues....

** Brand new DCEC head, genuine gasket used and had rocker pedestals machined to allow ARP head studs on install. Also had PDD 60lb valve springs swapped in and valve clearances set to spec.
** Removed sump to install rear dipstick tube with no issues.
** Installed new oil drain tube to bottom of the block, again with no issues.
  1. Firstly started trying to crank with injectors, fuel lines all ready to go(less turbo and intercooler etc) but basically would not wind over by key.... as in it felt like not enough juice in the battery. Could still do manually but was tight.
  2. Added lithium jump pack and still did not crank as I think it should have.
  3. Rechecked valve clearances and all at spec at Intake = 0.010 and exhaust = 0.020
  4. Removed injectors to eliminate compression issue.... I don't know how to attach/upload the video I took of it, but it will crank though seems to struggle and to me doesn't sound 'normal'. No nasty noises but not a flowing crank over. Seemed to draw a heap of power.
  5. During the above scenario, battery was fully charged and even put a lithium lump pack on during the video. Went from 14.8v with both battery & jump pack to 12.8v after trying to crank over for about 8-10sec without injectors in.(NB manual trans and was in neutral during all processes)
** Attempted removing pushrod cover on the side of the engine to inspect... but how the hell do you get that front bolt out from behind the IP?? (VE pump)

Thinking Camshaft issue possibly, but other than that..... why would it not want to crank over normally with the changes I've done if I can turn over by hand??
Could something else have happened??

Alot more detail in my original post so here's a link if needed Head replacement and tech questions
 

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Discussion Starter · #3 ·
I'd check timing for sure, and make sure no fluid on top of the pistons, which can hydro lock.
I might be not 100% understanding correctly, but removing and replacing the head should not affect timing at all, correct?? So no, I don't feel the timing should be an issue.
100% no fluid on top of the cylinders, removed injectors to crank engine and zero fluid came out.
 

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A couple questions. #1, how big are your battery cables? Should be at least 2/0 ga. Not 4 ga or 2 ga. Starter on these engines takes a ton of current and small wire won't do it. Ground cable should be the same size and attached to the block. #2, hate the thought but when that push rod dislocated you could have accidentally bent a valve. On getting that tappet cover off welcome to the world of Cummins. Pretty well impossible to get it off with the injection pump in place. Probably why they might charge a couple hundred $$$ just to change that gasket. If you could do a compression test that would verify that all cylinders are sealing. Removing the injection pump isn't a major ordeal on the VE pump. You can access the pump shaft nut from the cover in the timing cover. Just be absolutely sure the key in the pump shaft doesn't fall out into the gear housing. Then you do have to take everything apart. As long as you don't disturb the pump there would be no change in timing. Think I'd check the compression first before going to all this.
 

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Discussion Starter · #6 ·
A couple questions. #1, how big are your battery cables? Should be at least 2/0 ga. Not 4 ga or 2 ga. Starter on these engines takes a ton of current and small wire won't do it. Ground cable should be the same size and attached to the block. #2, hate the thought but when that push rod dislocated you could have accidentally bent a valve. On getting that tappet cover off welcome to the world of Cummins. Pretty well impossible to get it off with the injection pump in place. Probably why they might charge a couple hundred $$$ just to change that gasket. If you could do a compression test that would verify that all cylinders are sealing. Removing the injection pump isn't a major ordeal on the VE pump. You can access the pump shaft nut from the cover in the timing cover. Just be absolutely sure the key in the pump shaft doesn't fall out into the gear housing. Then you do have to take everything apart. As long as you don't disturb the pump there would be no change in timing. Think I'd check the compression first before going to all this.
Thanks Char. Battery cables are plenty thick and functions perfectly well without issue prior to removing the head.
Will see my mate and check if he has a compression tester at his work(diesel mech).
I've just left for a while cause my expertise is not that in depth at this level of trying to diagnose issues so had to wait for my my diesel mech mate to pop over this arv and had a look at things. He picked a strange 'tunk' noise while rotating by hand. Couldnt pin point exactly so process of elimination...we removed the IP gear.... noise still there. Then removed the lower hydraulic pump gear.... noise still there. At this point. there is only main crank gear and cam gear in place. Oil pump has been removed, IP gear & hydraulic pump gears all removed.
I finally got round to getting putting the videos on youtube so hope this might help someone point me in the right direction.
video of the car cranking over(prior to removing all the front gear assemblies)
Cranking over just sounds like its tight/struggling to wind over this is with injectors removed so no compression as well.

And try and diagnose this 'tunk' noise while manually turning over
Diagnose that 'tunk' noise

Thoughts??
 

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There is another ugly possibility. You could have a broken cam shaft. Has been known to happen. Remove the valve covers and see if all the valves are opening and closing normally. Something is definitely wrong. With no compression the engine should spin fairly easy. Another thing, you might remove the push rods and check them to be sure none are bent. I suspect your issues are connected to the valve train. That unknow noise is not a good thing.
 

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Discussion Starter · #8 ·
There is another ugly possibility. You could have a broken cam shaft. Has been known to happen. Remove the valve covers and see if all the valves are opening and closing normally. Something is definitely wrong. With no compression the engine should spin fairly easy. Another thing, you might remove the push rods and check them to be sure none are bent. I suspect your issues are connected to the valve train. That unknow noise is not a good thing.
Yeah, we were kind of thinking fractured cam as well but didn’t want to mention it before someone else did. I have all the front out(radiator/AC condenser etc) so hoping to pull the push rods out, dowel the lifters up off the cam and hopefully remove the cam without pulling the motor.
Argghhh the headaches!! And these parts are not readily available locally. I ‘may’ be able to source a Colt Cam stage 3 from Double Duty diesel here in Oz IF his website is correct in saying he has one in stock. Anything different we’d need know to install one of these. Prob worth the upgradeif I can afford it right??
 
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