B7000 Z650 engine

finchrat

New member

Equipment
B7000
Mar 4, 2009
13
0
0
calabasas, CA
Hi All,

I need to replace the engine in my B7000 kubota.. Cracked block etc..this one is hopeless..It uses the z650 but I cant find that engine anywhere. Does anyone know if another 2 cyl engine will fit in this tractor?


Thanks,

Damon
 

finchrat

New member

Equipment
B7000
Mar 4, 2009
13
0
0
calabasas, CA
Vic,

My neighbor had the kabota field tech over to fix his tractor so I had him look at mine. He knew a few things I didnt. He said there is some water in the engine oil..not just water in the radiator like I had thought. He says most likely its a cracked block and I might as well look for another engine. I wish it was just a freeze plug but he didnt think so. I may still check that but its not looking good. Im lost without my kubota!


Damon
 

Mr. K

Administrator
Staff member
Feb 14, 2009
522
138
43
www.orangetractortalks.com
Agreed. There are frost plugs all over your engine block - some in really hard to get at places (ask me how I know!). There is one in the cylinder head, one behind the gear case cover a few on the sides of the block, etc.
 

finchrat

New member

Equipment
B7000
Mar 4, 2009
13
0
0
calabasas, CA
Guys,

The oil color is cloudy and its about 1/4" above the full level of the dipstick. The radiator has alot of oil in it but I know it floats on water so dont know just how much but if you stick you finger in the fluid it comes out pure oil. The tractor doesnt have more than 10 minutes running since I rebuilt the head and changed the oil as well. Running the tractor does not increase pressure at the radiator opening. I was able to pump it up till I could pump no more..the gauge isnt working on my old stant radiator tester but it held the pressure. There is a pulsating pressure at the dipstick hole increasing with rpm.
I did watch the video on this problem but wasnt really able to get the pressure loss at the cap you discribe.

Somehow I dont think this sounds good..


Damon
 

finchrat

New member

Equipment
B7000
Mar 4, 2009
13
0
0
calabasas, CA
Ok I did those tests. No bubbles at all around the head/cyl area under pressure. The glow plugs have some fluffy carbon on them but thats all. No sign of oil or water.
Is a compression test in order? Would have done that but I dont have that size adapter for the plug hole. Can get it though.

Once started the tractor idles just fine..nothing out of the ordinary. It is hard to start..much harder than before I had the head rebuilt by the kubota people. WHen it does start it blows out alot of diesel smoke. Once cleared out it runs fine. Its like it piles up in the chambers while sitting.


Damon
 

finchrat

New member

Equipment
B7000
Mar 4, 2009
13
0
0
calabasas, CA
Wow I know I must have got some of this right :)

-The reason for rebuilding the head was this oil in the radiatior problem. I noticed it blowing oil STRONGLY out the overflow tube. Thats what got all this started. Talked to the kubota shop and they said most likely blown head gasket. So I took the head off and had it gone through anyway ( they said it was a mess inside) It did the same thing afterwards with the same intensity.. pressure in radiator and oil out the overflow.
-I did torque the bolts in sequence. New gaskets used. Didnt see any white sealer on the bolts that I recall. I could be wrong though.
I did put the bolts back in the right spot. I photograph everything and every step as I dont trust myself. No I didnt save the photos unfortunately.
-The smoke is black/grey and diesel smelling. Takes about 2 minutes after prewarming to get it going and it clears in about 15 seconds. As I said this was a definite change from its previously easy starting.
Could the valve clearance have changed after settling in?
I could have set that wrong too...but like I said it runs like a champ once its started.

-I didnt have any coolant, water etc in the block after head was removed as the lower rad tube was off. Im in california too with the mild winter temps.
- The water neck was not cracked but badly corroded.
- The radiator always leaked. The shop had to recore it.

I cant find an adapter to fit the glow plug hole in my stuff unfortunately. I have 10mm but the thread pitch kubota uses is different. I also have a leakdown tester but again no adapter that will match the thread pitch.
I hope we can get this problem isolated its really bugging me. I havent taken the tractor apart yet in case there are further tests we can do Rechecked the radiatior pressure at 16lbs..holds solid for 3 min or so. Starting the tractor did not vary the pressure at all and I lowered it to 6 lbs.


Damon
 

mawest

New member

Equipment
B7000
Mar 7, 2009
2
0
0
Rindge,NH USA
Hi Do you have a WSm for the z 650 I need the crank spec,need to get my crank turned. Any help would be welcome, Thanks Mark
 

Roy Davis

New member

Equipment
B7000D
Apr 22, 2020
5
0
1
North Scituate RI USA
Hey Vic! While you're asking,
And were on the 7000 subject,
Just bought a 7000, kicking myself a bit due to not looking over this machine well enough before purchase, the shift boot is well worn and cracked, looking into fill hole transmission fluid is mixed with water....ughhh

Currently machine will not go into 3/6 and pops out aggressively, also PTO speed 3 grinds

I immediately dumped all the fluid,cleaned screen, disconnected both pressure hoses in attempt to clear it all out completely

re-filled, started and discoloration appears again

Assuming tractor may have been previously left out in the rain, am I making a good conclusion that water may have entered in through the cracked boot?

And within my seeming exhausting process of filling and and dumping transmission fluid just to get rid of however much water might be within, is this my only option besides physically taking transmission out and cleaning all by hand?

Additionally are you familiar with which gears in the transmission will need to be replaced as far as 3rd gear and PTO 3rd speed go?
I have exploded views of the complete transmission but don't know which are associated with the gears themselves
any help would be greatly appreciated!
 

skikir

New member

Equipment
B7000
Mar 31, 2010
12
3
1
Eugene, Oregon
I've been wondering if a z750 engine will work. I've seen replacement heads that quote z650, z750, B7000 and L1500. I've had my B7000 for 22 years and I know Nothing can liver for ever so I've been looking around for possibilities.