CASE 850 torque converter & driveshaft quit spinning

[cyberbiker0]

In the days before, the oil temp reached about 275 F (the max allowable) and seemed to drive fine afterwards, until the drive-train quietly quit responding. No bang or mechanical meshing noise, no external oil leaking/gushing. The converter oil pressure simply dropped to 0. The trans oil level is at correct level.



I've recently pulled the belly pan. Opened a drain plug (next to a relief valve), but nothing came out. I found crud by brushing my pinky finger inside. I opened the cover plate (facing the trans) & found no oil in that upper part. I poured 5 gallons of 20W in that opening till it overflowed just to find out a pipe carried the oil to the trans, but never came out that drain hole.

When I crank the engine, a gear at the cover plate seems to budge a tad. The equip pump gear & charging pump gear seems to try to turn. I don't know if it's due to a lack of power or locking up. when the engine is off, i can freely turn the driveshaft by hand but it takes all i have to budge those gears 1 inch. the gears look clean & in great shape.

Before attempting a major overhaul & based on what I've explained, can any1 advise me on some Q's & A's? Can tiny bits of crud, sludge or foreign object(s) be freezing-up it's rotation? Shouldn't oil drain out the plug (beside the relief valve, item# 50) or is that hole chambered off from the cover plate (item# 25)? If not something simple, what part(s) in the converter could cause it to quit functioning like this?

 

[sheepfoot]

The first thing is to take the relief plunger and springs out of # 32. Be ready because it may have some force behind the plug when you unscrew it. It may also have shims to increase the spring force. This is the pressure regulator for the charge pump. Also remove the plug and springs and 48-44, that's converter pressure/cooler and it will have force on that plug as well. Check your filter for trash, upper and the suction screen lower filter, check the suction hoses that they are not sucking together and the clamps are tight. You can check the upper filter top for a 1/8 pipe fitting to install a pressure gauge or you may have to tee into the line. The trans pressure should be 260-290 psi at 1800 rpm and the converter out regulator should be 25-60 psi. You may have lost the key in the charge pump to gear shaft. It has to screen oil, suck oil, pump oil, filter oil, feed the control valve and regulate pressure, converter coupled, and cool oil. You could also pull the pump first and check the gear and shaft, it's a pain but these are some of the steps to do before thinking the converter is bad. Ask if you have more questions.

 

[cyberbiker0]

Thanks bunches for the info & speedy reply Sheepfoot. I'll surely give those ideas a try & hope for the best. I surely hope those items are not under tremendous force & that I'll be able to put back together. forcing spring-loaded things back together can make the 4-letter words rip

 

[Tinkerer]

Is the convertor rotating with the engine running ? If not, maybe the flex plates are broken. Not trying to be a smarta##, but they connect the flywheel to the convertor.

 

[cyberbiker0]

@ sheepfoot. I checked those pressure fittings today, but wasn't sure what to check for. The springs & pistons looked to be in good shape. They was a bugger trying to screw back together. What was i suppose to look for? ...besides a pressure reading.

@ Tinkerer. Nothing about the torque converter is spinning, but it looks like it's trying to turn when the engine is running ...such as budging but like it's trying to fight rotation, while the drive-shaft is easily turned by hand. I did hear some bad news today when I ran a coat hanger through the drain plug. It sounded like a thin metal piece rattled. :beatsme I fear it is part of the shim(s). I did wonder how the converter attached to the engine. Knowing what you said, I might have big worries

The only ray of hope I might have is that a previous owner used the wrong type of suction element & that mounds of trash got in the charge pump gears, causing its resistance of rotation. .....and that the shims aren't totally ruined. Perhaps I'm just dreaming but wish me luck.

 

[sheepfoot]

Does the loader still raise, lower and dump ? If it works the flex plate are still turning the converter.

 

[Heavey Metal]

Your flex plate is torn up if the motor cranks and the converter dosnt spin with the motor running.

 

[Tinkerer]

Flex plates are hardened sheet metal. You can see them in the parts diagram on the front of the convertor. They appear to be #18. Your coat hanger is most likely moving a piece of one of them around. It is not uncommon for them to fracture and then shear into pieces.

 

[cyberbiker0]

well, the mystery is solved. i opened up the inspection plate on the flywheel housing & seen the shims damaged. the flywheel spun, but the converter slipped-grabbed-slipped. so it looks like a major task on my hands.

on a side note, the gear on the charge pump wiggles a lot and when turning it has a lobe of 1/16th of an inch. on precision parts, that should never be. plus i think it internally leaks, because i couldn't get much vacuum/pressure while hand spinning it & i heard an internal gurgling sound.

the problems just keep piling up. my JCB backhoe keeps pumping fluid out of the trany fill tube, even after treating it 2X's with "Seafoam" ....Calgon take me away!!!

 

[cyberbiker0]

Has any1 heard of transmission fluid pumping out of the fill tube? I wonder if having 2 gallons of 20W oil is over filling it. The service manual says that can happen if it's overfilled, but you'd think that using less than 2-gal seem like it would not be enough. Either it's suppose to run on 1.5-gal or could it be an internal fluid blockage?

 

[Tinkerer]

Are you using the exact procedure that the service manual specifies for checking the fluid level ? I learned the hard way how important that is.

 

[cyberbiker0]

Smoking Engine ...Perkins 6.354?

There is also momentarily engine troubles we been having over the yrs & while we have the motor out to repair, I'd like to fix this too. This Perkins engine will run fine, till out of nowhere it'll start misfiring & sputtering. It looses nearly all horsepower & backfires through the exhaust. White & Black smoke billows out.

What we been doing when that happens; Taking the load off, run it at idle, or let it sit for a while & it'll go back to running normal again. Could this be what caused the flex plates to be damaged?

To narrow it down; it's not a dirty air filter, not water in fuel, it's not turbocharged, engine does not overheat. Here is a video clip to demonstrate it happening.

https://www.facebook.com/photo.php?v=990865690939212

 

[sheepfoot]

The 850 case machines had a case 301BD engine, has your engine been changed out to a perkins ? . Can you post a pick of the fuel filter set up along with the injection pump. A good pic where the pump bolts to the engine and one on the end cover of the pump. The pump should be a inline 4 cylinder with some having a adapter housing between the pump and front housing depending on s/n.

 

[Tinkerer]

Could this be what caused the flex plates to be damaged?

No, they just deteriorate from flexing over a long period of time. If and when you replace them follow the procedure described in the service manual. They may need to be shimmed to get a specific distance from the flywheel. When the engine starts running poorly. Stop and remove the fuel tank cap and see if there is a vacuum in the tank due to a plugged vent. That is the first thing I would check.Like Sheepfoot said, post some photos of the fuel pump. I don't understand why anyone would go thru the trouble of replacing the Case engine with a Perkins. If they did, that may be the cause of those flex plates shearing.

 

[cyberbiker0]

^^^^^ driver side ^^^^^



^^^^^ passengers side ^^^^^

The engine in my service manual looks way different than the engine in these 2 photos. I'm just taking a wild guess (by visual) that this looks more like a Perkins 6.354 engine ...that a previous owner dropped in. Possibly to save money. They also substituted an 850 torque converter with a 750 torque converter, or so the stamped-on tag says so ...found on the upper passengers side housing.

 

[melben]

I would agree that it's not a Case 301 engine, It does have some characteristics of a Perkins. I know that we here on forum have ran into things of this sort for equipment built for foreign markets. Or it could nave been swapped in. Interesting if I must say so.

Mel