Case 450 advice

[Jednlulu]

First thing i did when I bought her I redid the brakes. So, even if I use brakes, especially when cold, she just bogs with slight turn. Same effect turning as if i toggled the levers for transmission. (Intermittent pumps to one brake or the other will eventually turn in the direction i need to go). Now, when she warms up, she'll turn but, same condition as if with using tranny to turn. Mostly bogs down...just like she has no power. She runs much better when warmed up completely but just doesn't seem to have the pushing power she should. When warm she will move quite well (on level ground) with both tracks on high (with no load). She'll turn decently too but, I still occasionally have to toggle. (That's with no load).
I'm thinking it's fuel / engine related because (from an earlier post) it was mentioned that if trans trouble, the engine would continue to revv but the power wouldn't transfer to the rear end. And in my case, the motor bogs, causing (I think) the tranny to lose umph to be able to move.
I'd inquired about the charge pump (inadequate pressure to Torque Converter / Transmission, etc) awhile back but a guy told me that if the charge pump was worn, I'd have to be manually priming it.
When revved high, the torque converter pressure is high. (Can't tell what trans pressure is doing, guage isn't working yet). And, when motor "bogs" I lose torque converter pressure. That help with your trouble shooting? I really appreciate you taking the time to try and help me out Baz.
Thanks, Jason
I just thought....if I'm creeping along and I've got the blade raised up and it "stops" at the end of the stroke, I lose even more ability to move....could I be overlooking something with the charge pump??? This thing is making me crazy!!

 

[thebaz]

I am not sure if I am getting the full picture, but it seems like this machine is not working anything like it should. What happens if you put one track in neutral, (between high and low) and the other one in low?
There is a valve on some 450s that stops the brake pedals from disengaging the tracks from the trans so you can use the brake on a hill without the machine running away. This valve will stop the machine from doing pivot turns with the brakes. If you don't have the valve you may have a problem with getting hydraulic pressure from the master cylinder to the "knockout valves on the trans that disengage the track drive from the trans, (steering clutch).
Baz

 

[Iron@Dirt]

If this inj pump has kill cable or linkage, make sure of full stroke. Parcial travel can kill power. A pic of pump could help. Also fuel restriction could cause smoke or not, but drop HP (some inlets have screen that can clog).

 

[Jednlulu]

Baz, I rebuilt the brakes and confirmed that the pressure to trans drops out prior to discs engaging. That all seems to be working as it should. After warmed up, when moving in low (both tracks) if I depress one pedal or the other, I can "feel" the track drop out (slight turning) and if I press more, the track "locks"). The machine just doesn't have the power to turn quickly, just kind of loses it's umph and bogs. Overall, I really believe the inability to move correctly or push correctly stems from loss of engine power...for whatever the reason.

As far as accelerator linkage, i mentioned earlier that the linkage was bent right at the governor but, i can see that when accelerator is depressed, the "yoke" that the throttle rod attaches to at the fuel pump rotates clockwise fully (until the "stopper" screw bottoms out against the fuel pump housing) despite being a little bent. I even tried to back that screw out (to achieve more stroke) but the accelerator pedal bottoms out on the stand bolt. I thought about lowering that stand bolt but, again, with out "load" (load here being defined as either moving or pushing dirt) she revvs up real nice and high (and T.C. pressure is near the guage limit).
Iron@Dirt, thanks for joining in....I'll grab a pic of the fuel pump after work and post it for further consideration. Thanks guys, Jason

 

[thebaz]

Iron@dirt has a good point as this would create the exact symptoms you are talking about. So check that the stop cable is returning to the full fuel position, also even though you have replaced the filters, check that there is good flow through the fuel system to the pump. Puting the brakes on to turn the machine should have very little effect on the motor rev wise.
Baz

 

[Jednlulu]

fuel pump

Not entirely sure of what you mean..:beatsme...but, if I push the accelerator pedal down, the linkage completely rotates the yoke clockwise until the adjustment screw bottoms out against the housing....see pics attached.
Also, the fuel line that supplies the pump does have a filter screen. I've pulled that and cleaned it out thoroughly too.
Thanks again for your help!:Banghead

 

[thebaz]

Ok, first, I am assuming that the throttle linkage pushes when moved to full throttle and your photo shows that it is hard up against the full throttle stop. Is this correct? if that is the case the n this all looks OK, (even though it is bent up and messy)
Second, In the second pic you can see the stop cable between the engine and the injector pump. You need to make sure that that is hard up against the open stop. (push the lever as if the cable is being pushed not pulled) Of that lever is mid way the motor will run be be way under fueled and give the type of problem you describe.
I hope that is the case.
Also, does the 450 have a lift pump on the motor that feeds the fuel filters? If it is gravity feed you may have to fill the tank full and get the 450 facing down hill then check the flow of fuel and bleed all the air from the system.
Baz

 

[Jednlulu]

Baz, the top photo shows the throttle linkage. In the pic, it's "at rest" with no depression of the accelerator pedal. WHen you press the pedal, the "yoke" that the throttle cable attaches to rotates clockwise. Note the adjustment screw is "loose" / the locknut is not seated. I assume that the guy I got her from was struggling with same trouble as I didn't loosen it up. When depressing the pedal, the linkage moves to the right and the adj screw bottoms out against that round protrusion.

I never even noticed the stop cable (bottom pic) until you mentioned it. Now, what exactly does that do? What "should" it do when accelerator pedal is depressed? And, what / where exactly is this "governor"?

As far as fuel supply, to my knowledge it's only gravity fed. I thought about disconnecting the fuel supply line and applying compressed air back to the tank to make sure it's clear. At what rate should fuel flow through? Thanks again!

 

[FurakawaMatt]

And, what / where exactly is this "governor"?

You show it in your picture. Here is a handy description of a Bosch pump with governor.

The stop cable linkage would be used to cut off all fuel being delivered. I guess that is why Baz asked if it was in the partially closed position.

 

[thebaz]

The governor basically does two jobs, 1 is to limit the maximum rpm that the motor will do, very important in a diesel as they are generally only designed to operate at low revs, 2 is to allow more fuel to be supplied to the motor when extra load is applied to maintain whatever rev range you are working at. If the governor is faulty you may get full throttle with no load but it will die when a load is applied.
The stop lever should be hard up against the limit screw when the cable is extended when the motor is running, if it is in the opposite position the motor will stop or not run. If it is in the half way position you will get the exact problem that you describe, the motor will rev but die when a load is applied as the governor will not increase the fuel delivery with the stop lever in this position. YOU NEED TO ELIMINATE THIS OUT OF THE PICTURE as it is the most likely and easiest to rectify.
As a side not, it is a big no no to mess around with the full throttle adjustment screw as it can allow the motor to rev higher than it was designed to, and you will not really get any more power, just higher speed.
Baz

 

[Jednlulu]

The beast has come to life!!!

Thanks so much for all the continued advice and help. I feel like a "rhutard"...the stop cable wasn't fully extending when pushed in! I had no idea this girl had so much power!! I bet the guy that sold her to me could just kick himself in the arss right now! She's a runnin' MACHINE again!
Now, if only she had a new undercarriage! Thanks again for all your help guys, you're the best. I owe you BIG TIME!! :drinkup

 

[FurakawaMatt]

Glad it was something simple for you to find and correct. Iron@dirt had it right. Kudos to him, also theBaz (and you) for getting it fixed. :drinkup

 

[thebaz]

Glad that worked.
It is always good when something so easy to fix can make such a huge improvement, rarely happens to me though, although I always try the easy things first.
Enjoy.
Baz

 

[thebaz]

Oh Yeah, and Kudos to Iron@dirt, he really nailed that one.:notworthy

 

[Jednlulu]

Thanks again guys, your supportive direction really helped me A LOT! Any advice for the undercarriage? As far as I can tell, the pins look to be in decent shape, only slightly ovaled. The drive sprockets however are near razor sharp at the tips. Can I only change the sprockets out without messing with the chains / pins or is it advisable to only do both at the same time? I was wondering if new sprockets would "mesh" well with the old pins....thoughts? Thanks again for all the advice and help!

 

[Iron@Dirt]

thebaz and FurakawaMatt, Thanks for all the help yall give people.

 

[Switek]

Case 450 Crawler (1978) -- Couple Problems

While we are on Case 450 problems...Can't seem to post my own topic

First problem I have is with the track adjuster on the left side looking from the front. Grease leaks out the front of the cylinder. I don't know if we blew the seals on it or they just wore out, but it will tighten like normal but pushes the grease out and loosens the track within an hour or two. I think I know how to replace (hoping only seals) but if someone could walk me through the process that would be a great help.

Second problem I am having is with, I believe, the torque converter or its charge pump. I have over 200 psi on the torque converter pressure gauge when accelerating engine when it is still cold. It drops back to about 100 psi when idle and still cold. When oil gets hot, it will not get much above 150 when accelerating and drops to near 0 psi when idle. Dozer was in the barn for the last 2 years and started backup like a dream (Only drained fuel and charged battery started on first push) so I know it is in great shape. Had both these problems when we parked it and have meant to get back to them.

Thanks ahead of time for any help.

 

[Switek]

As far as brakes go, we have had this dozer for well over 15 years and I don't ever remember using them...ever, for any reason.

 

[thebaz]

Hi Switek,
The track adjusters are usually the victim of corrosion on the rod surface where the seal runs. When you adjust the tracks the roughness of the rod rips the seal apart. There are complete aftermarket adjusters that can be found pretty easily. You may be able to replace the rod with some 4140 ground bar and get it machined to suit, then replace the seals and you are good to go.
If you just replace the seals you will have the same problem if the shaft is damaged.
You will have to split the tracks and undo the bolts holding the adjuster to the idler. The bolts may be stubborn to get undone and may break in the process.
Baz

 

[thebaz]

First thing to do with the trans pressure is to clean the suction filter for the charge pump and replace the oil and trans filter.
Always fix the easiest things that can create the symptoms first.
Baz