1845C Engine Seems Very Hard to Turn

Now that I have smoked a brand new starter thought I would seek advice here.

Have an early 1845C. About two years ago was the last time it ran. I have replace ALL electrical connections, starter, and battery. Meaning that all battery cables, wires, and switches going to solenoid and starter are new and bigger than they probably should be. The solenoid was just clicking before, but after all the new parts the starter gets a good bite on the flywheel, but most often only moves engine 1/16th of a rotation or less. A couple of times it was able to crank it maybe half a rotation. I was looking at the u-joint to determine the movement.

The last time it ran it quit before I shut it down. I am fearful that maybe it ran low on oil. It does have some sort of buzzer hooked up that presumably would have gone off with low oil pressure but I never heard that. Anyway, it does seem to leak or loose oil and I don't know if it lost oil pressure or not. I have since put more oil in it and I don't know if it had enough when it last ran.

I tried turning the engine via a 2 foot pipe wrench and was not able to get it to move. So IMO something is making it very difficult to turn. The only other thing I can think of is that I have a connection that obviously went to the positive post on the starter at one time. Do these engines have some sort of electric compression release that gets activated during the start cycle? I did not hook that back up because I did not know for sure that it came off the starter post and it looked a little rusty like it had just been hanging beneath the starter.

Would and engine with spun bearings even turn? Is there a compression release driven by 12 volts? Any help or ideas is appreciated.

There's no compression release that I know of.

I'm guessing that it could be either the engine or the tandem pump. The best way to know would be to unbolt the coupler in the middle and try turning the engine over by hand. If it spins, then the tandem pump has issues.

With a 2 ft pipe you should be able to turn the engine. You'll get resistance on the compression stroke, but you should be able to wait a few seconds and then turn it slowly. Could pull the injectors, then it should turn much more easily.

Where was it parked when it last ran? It's possible that corrosion has seized the piston rings to the bore.
It's also possible that one or more cylinders have filled with oil or water from an internal leak and is now hydraulically locked. Whatever the case, you want to get it moving with a bar before you try the starter, you can bend a conrod if you haven't already.
I'm sure you'll get more qualified opinions than mine soon, but I would pull the injectors first, and then try barring it again to see if any fluid escapes.

If the rings were seized they are no longer as the engine has turned a couple of revolutions total since last parked. I know that is not a good thing as you mentioned because I might now have bent a rod and I guess it is possible that I busted a ring if they were seized. It has been outside the entire time in two Colorado winters. Both suggestions sound good to me. Disconnect u-joint to isolate main pump. Try to turn with pipe wrench. If easier then problem with pump. If still difficult then remove injectors and try turning to see if fluid escapes. Thank you both.

Do you have an operators manual for the machine? They are usually in a plastic box mounted on the ROPS behind the cab. The reason I ask is the 1845C has a cab that will slide forward to make working on things much easier. It is a pretty basic job but having the instructions in the manual makes it much easier for the first time.

I've seen two of these engines run out of oil and they both threw a rod through the block. Another possibility is something hydraulically locking the tandem pump. Does it turn easier one way or the other? As others said disconnect the pump from the engine and go from there.

Two years later....time is flying.....

Finally separated the tandem pump from the coupler. Tandem pump turns but the engine will not.

Would the hydraulic pump at the rear of the engine be able to prevent the engine from turning?
Just wondering if it is worth it to pull it off.

If it's the engine I think this machine will be on Craigslist in the near future ASIS.

well a seized pump could be the problem so disconnecting it would be worth the time it takes to remove.

Almost wish this machine was close to me as I might be crazy enough to buy it if it was at the right price. Just for your information a Case 1845C sold near me for $3,000 at an auction with a non-running engine. Then again one just up the road from me brought just under $7,000 that one did run! A running engine is the main difference. $4,000 is about the average price of a running take out. Then again have seen them for just over $2,500!

Just pulled the rear pump and it also turns by hand. So the engine is seized. Just put on Craigslist for $4,800 and hoping to get $3,500. Thank you for the suggestions to pull the pumps!

have you removed or loosened the fan belt? that will make an engine very hard to turn if the alternator locks up.

Thanks Delmer, I'll try that in the morning

Even if the motor is locked up, those Cummins 4-390's are fairly simple to replace with a used one or repair them.

I think if not already done I would be pulling oil filter and cutting it apart to see if there is any metal in there. Seems like if it was siezed or starting to it would have at least enough to show up in the oil filter, same for the hydraulic filter.

I've heard that there are relief valves somewhere that I am supposed to loosen if I am going to try pulling my 1845C Uni-Loader any distance.

Does anyone know where that is located?

steven1845c said:

I've heard that there are relief valves somewhere that I am supposed to loosen if I am going to try pulling my 1845C Uni-Loader any distance.
Does anyone know where that is located?

Click to expand...

Here's a pic. You just need to loosen them a couple turns.
https://www.heavyequipmentforums.com/threads/case-1845c-drive-issues.66591/#post-692412

Tinkerer said:

Even if the motor is locked up, those Cummins 4-390's are fairly simple to replace with a used one or repair them.

Click to expand...

Thanks Tinkerer. After describing the final moments of operation to my cousin he was fairly certain it might just be a crank job. He was right as all mains were good and just one rod bearing seized and two more scorched.

While he's fixing that I plan on cleaning the machine and replacing the chain case covers and fluid plus changing out the hydraulic fluid / filter. Are there any tricks to finding hydraulic leaks without running the machine? I would really like to make sure everything is leak free before I reinstall the engine. Also, is there such a thing as "flushing" the hydraulics an if so does anyone know how that is accomplished?

To find leaks it would be better to have the engine running for a high pressure from the pump.
Unless the oil smells like something burnt or it looks milky from water intrusion, I don't think I would bother flushing it.
There a couple of old threads that describe in detail how to do a complete flush. It requires a lot of oil and at least two filter changes.

Engine rebuilt and re-installed. Thank you to those who suggested I replace the 4-390.

How "tight" do I need to get with the 1.25" fittings on the hydraulic hoses. I have 6 fittings that have an O-ring that sit against a beveled face on the drive motors. They moved when I was trying to get the old hoses off and now they leak. I have new O-rings coming and wanted to know, before I crush the new O-rings, just how tight they should be.

https://www.new-line.com/information/tightening-torque-recommendations-for-hydraulic-couplings

Sounds like an O ring boss fitting, but you can double check that and the size. You won't crush the o ring by tightening it. But you need to keep the o ring from twisting during tightening, or letting the fitting loosen and twist the o ring by moving under pressure, that's how they fail.

Delmer said:

https://www.new-line.com/information/tightening-torque-recommendations-for-hydraulic-couplings

Sounds like an O ring boss fitting, but you can double check that and the size. You won't crush the o ring by tightening it. But you need to keep the o ring from twisting during tightening, or letting the fitting loosen and twist the o ring by moving under pressure, that's how they fail.

Click to expand...

Thank you Delmer. Definitely a ORB. Glad to know I can just tighten it well.