We have an older 590Turbo with a Cummins 4T390 engine that died while we were using it a while back. In trying to diagnose the problem, I pulled the front valve cover and it looks like the camshaft isn't turning though the starter does crank the engine. How hosed is it? Is that a zero clearance engine or is there a chance that it isn't going to require a major overhaul. It has 6450 hours on it, it had 6356 when we bought it, they told us it had an in-frame overhaul at about 5000 hours. I'm not an experienced mechanic but can handle most things with good instructions and manual. I have the Service Manual and Parts Manual for the backhoe. Any insights, help, or advice will be much appreciated.
Pull the round cover off in front of the injection pump and see if that is all still turning. Been a while since I have been in one of those engines but I do believe they are an interference engine chances are though all it would have done is bent push rods though
Dumb question time, how does that cover come off? is it threaded on or press fit?
If it has a tachometer drive it is behind it.
Thank you. It doesn't have a tachometer drive, but there is a round cover where it would go, does that cover come off without removing the complete front cover? I have the manual and have seen the instruction to remove the tachometer drive assembly, but I don't have the magical knowledge of how it comes off.
in the pic in "step 4" at the bottom of the hole, doesn't that look like a gap between the ends of a single thread? try unscrewing the cover counterclockwise.
Turn it 1/4 turn counter clockwise
U need a big pair of channel lock pliers or a big oil filter wrench or a strap wrench.. the cover has an oring on it that’s very tight.. & yes, it unscrews..
Finally getting back to this, the gear driving the injector pump is turning.
pull your valve covers and see if valves are moving or is anything wrong in there, bent push rods, broken rockers,broken valves
Thanks. We started this by pulling the front valve cover and the push rods aren't moving. I'll pull the other three and check them.
One possibility is a broken cam drive gear. They can break in the “webbing” and that causes the cam to stop turning but the outer diameter of the gear can continue to rotate, driving the IP still.
Like this.
If I were you I would pull head valves have hit the piston damaging valves and piston
Had one of those that the cam snapped right ahead of the front cam bearing, personally on those engines I have never see a broken gear but looking at the pic of that engine obviously it can happen!
I guess I should give an update. We pulled the front cover and found that the cam shaft was broken right behind the front bearing. Along with that, the key on the crankshaft was sheared. We went ahead and pulled the engine so we could remove the (rest of) the camshaft and inspect further. As we continued our examination, we found that the bolt directly above the crankshaft that holds the front housing to the block had come loose and dropped into the gears. Based on comments on here and from talking to a few seasoned mechanics, along with getting estimates of the cost for a full overhaul, we ordered a new engine today. We were able to get a complete new engine for significantly less than the labor estimate for work that would need to be done to do the overhaul.
Okay, next noobee question. The manual says to put "loctite liquid teflon" on the intake manifold cover bolts. In searching, I don't find any product listed as simply liquid teflon, but I find about a dozen different products described as teflon thread sealant. What is the right one to use? Thanks!
Teflon is the same as PTFE, just a different name.
Thanks, I knew that PTFE is Teflon, it was the thread sealant part that had me wondering, the manual just said "liquid teflon" which I have used as a lubricant in other industrial applications.
Ran into another issue. four of the six bolt holes in the flywheel housing where the torque converter cover attaches are stripped. I've drilled and tapped them for heli-coils, but am wondering about the thread length. The bolts are 30mm long and the original holes were tapped to that depth, but the only heli-coils I can find are only 15mm long. Do I need to double heli-coil them or is the 15mm enough thread? From what I've been able to find the standard best strength thread depth is 1.5 times the diameter, which would make 15 mm right, but those are all talking about steel. What about aluminum?
Just a follow up, McMaster-Carr has 30mm long inserts.
Had one that over heated and sheared the crack gear key off and jumped time bent a few push rods put it back together and it's still running. Probably not the right way but the machine wasn't worth rebuilding the engine
We got it all back together tonight (finally), anxious to bring it to life. Started going through the startup procedure that came with the new engine, and can't get any oil moving. The procedure said to crank the engine (no fuel) in 20 second intervals to keep from overheating the starter, until it shows at least 10 PSI oil pressure. After at least 20 times cranking, still no sign of oil pressure. checked the gauge port and the oil filter and no sign of oil at either. Any help will be greatly appreciated.
You really need to contact the vendor that sold you the engine. It is their problem and they need to know ASAP. IMHO. I wouldn't keep turning that dry engine until you get some answers from them.
It needed to be primed. We pumped about 2 gallons of oil in through the Oil Pressure Switch port. We now get 30 PSI cranking with the starter. Now to bleed the fuel lines and see if it will start.
I hope when you put the cover back on the engine you used loctite red preferred on the bolts behind the cam. Seen many a bolt come loose and shear the crank key and break the cam off. Back in the day at the dealership we used to pull the cover at 500 hours service and check them for loose, submit a warranty so no charge to customer. Sometimes it makes a mess of all the gears.
Same machine, next problem. The oil temperature sender on the engine has failed. I can't find any reference to it in the Case parts catalog and after 45 minutes on the phone with the dealer, they sent me a temperature switch, not a sender for the oil temp gauge. Can anyone point me to the correct sender?
What is the exact model of your 590 ? SN ? What tier is the engine ? There are 10 different parts books for 590SN's.
It is a Model Number 590, Product Identification Number JJG0205506 (original) Engine Serial Number 44573831 It is the sender on the left, the one on the right is the water temp sender.
I believe that is a coolant over heat switch not oil. Bob
Thank you. I must have been half asleep.