New to forum with case 680CK questions (hard start)

dbosco002

New User
I have been working on a very old 680CK. I rebuilt the cylinders on the hoe and have used the backhoe a little bit around the property. the problem is that it starts really hard and I have to use a charger because I have to crank it for so long. Once it fires up you can hear that two of the cylinders start to fire up after it is running a bit. like the fuel is just getting to those cylinders. (sounds like when you put a plug wire back on a 4 cylinder 4 stroke when it is running). I bleed the lines and it looks like i can see little bubbles on the line for the cylinder that is furthest back on the tractor. Why would there be bubbles in one and not the others? is it a bad lip seal or something? has anyone had that problem it is a A267D probably around a 1966 vintage. once those cylinders fire she runs very strong.
 
1st thing I'd do is a valve adjustment. If that doesn't cure it, pull the injectors & do a compression check. They all should be around 450psi. Keep us posted.
 
Is the electric fuel pump working, it is in the line from the tank to the filters on the old CKs.

Those were not the best starting engines to begin with but you sound like you are getting air from somewhere,

The injection pump is a multi plunger pump and no lip seals are involved in the fuel delivery portion of the pump. I have a 830 diesel that takes a bit to get fuel to all the barrels if it sits long enough and it takes a bit for it to start to throw white smoke while cranking. It works well after getting going and when fired up takes just a few seconds to get smooth. I believe that my pump has enough barrel leakage to allow fuel to seep by and leave air in the pump barrel where it must be purged after starting but mine does it without cracking lines.

If yours runs smooth and you crack the line and see bubbles I have a hard time believing its air, but I think air is causing your starting difficulties, or if the fuel pump is faulty, insufficient fuel supply at startup.

Those engines must turn to start I'd verify that it has the heaviest batteries in it that will fit the box , that all the cables are in excellent condition and the starter is also. You should not have to put a charger on it to get it turning. My 830 has a pair of 1000 amp Dekas in it and will start without block heat to the 30s and then with a bit of manifold heat below that. Cranking speed is all important, if it don't turn good find out why.
 
Both good suggestions. I only have one 1000 amp battery now. I was a bit worried that maybe it was not 12v but 24 or somthing. It seems to be very taxing on the battery and starter. I installed a lift pump i got got from the auto parts store. It makes about 4 to 5 psi according to the gauge i installed on the final filter. When i put a gauge right off the pump it will go up to 7 psi. Ithink fuel must be going around the piston in the injector. I also might have low compression. I dont know
 
is it 24V? I am trying to find info on this thing but not much luck... i found a starter online that looks like its the same and it is 24V
 
It originally had 2-6V batteries in series for 12V if it is the older 680. It would require recableing it to get parallel 1000 amp or 2000 cranking amps. However you decide to do it make sure the cables are in excellent condition and someone hasn't subbed automotive weight cables into it. For parallel each batteries negative should go to ground and positives should go to the solenoid post, Ideally the battery negatives could be one heavy cable if someone will make it for you and terminate at one of the starter mounting bolts.

After this when running make sure the charging voltage is 14V or near there.

Please bear this in mind, those powercell engines were not easy starters when cold, but if the manifold heater is working and it turns fast they are a lot better
 
So i put another battery in the tractor on tuesday with no luck. I need to start checking the compression and valves... One thing i question is if 4 psi is enough pressure after the final filter? I am running a mr. Gasket 12d lift pump..
 
(quoted from post at 13:40:29 10/23/14) So i put another battery in the tractor on tuesday with no luck. I need to start checking the compression and valves... One thing i question is if 4 psi is enough pressure after the final filter? I am running a mr. Gasket 12d lift pump..


Is it cranking fast? Does it smoke white while turning over?

Did you have the starter checked out by a reputable rebuilder to make sure it's good, the starter also has to turn the hydraulic pump and the torque converter upon startup so there is no room for weak components.

It may be time to get the compression check done as others have said as a low compression situation will defintely kill its ability to start.

Mel
 
(quoted from post at 16:34:40 10/20/14) 1st thing I'd do is a valve adjustment. If that doesn't cure it, pull the injectors & do a compression check. They all should be around 450psi. Keep us posted.


Anyone know what the valve clearance for intake exhaist is on a 267?
 
Most of those engines had a white decal on the valve cover with that info on. check there on the injector pump side.

If you have a 12 lb pump on and are only getting 4 lb sounds like the fuel relief valve located in the filter body may need stiffened up a bit. There should be a thin nut between the filters on the filter body looking right at you, in there is a relief valve, stretch the spring slightly, then see if the pressure comes up.

Is it turning fast, it must to start? everything else can be in tip top shape and that engine will not start if it don't turn fast.
 
(quoted from post at 09:09:29 11/07/14) Most of those engines had a white decal on the valve cover with that info on. check there on the injector pump side.

If you have a 12 lb pump on and are only getting 4 lb sounds like the fuel relief valve located in the filter body may need stiffened up a bit. There should be a thin nut between the filters on the filter body looking right at you, in there is a relief valve, stretch the spring slightly, then see if the pressure comes up.

Is it turning fast, it must to start? everything else can be in tip top shape and that engine will not start if it don't turn fast.

Seems to turn over ok to fire the front two cylinders which is why i think its maybe compression or injector. I pulled the regulator screw.... no spring in it!
 
It should have a spring ,that is what sets up charge pressure to the Inj pump. If you have a good fuel pressure the pump should clear itself quickly, my 830 is rough for 30 seconds or so. Get a spring, a Case dealer should be able to get it for you, check with John Salei, this forum. Is the other piece just floating loose in the bore?

Does yours have the flush nut on the side between the filters or a valve sticking up on top of the filters with lines going to it, is there a T valve there for bleeding? there was two different styles.

A while ago there was a gent complaining about blowing final stage filters out, Upon my advice he pulled the relief and found a stuck plunger.

You could get a generic spring and try it, you do not need much spring tension to get pressure but with that spring gone and the plunger slid back by fuel pressure the fuel flow is routed right to low pressure.
 
I tried a spring but got no change. The piston is all the way back in the bore and i didnt see a change in pressure. Ill find the correct spring. I took a video of my fuel injection line that i cracked to bleed air out. It looks frothy/foamy. Is that normal? The dngine was running for a few min but it still had lots of bubbles.!
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top