Bobcat 763 Blowby

[Hilbilly]

I,m looking at buying a 1999 Bobcat 763. I've checked it out and all seems great except that it has some blowby. The down pipe from the valve cover breather is not connected to the breather and I could see some oil below the breather. So I put my finger over the open end of the vent and could feel the pressure slowly build up. After a minute or so the pressure was enough to start leaking around my finger. The machine has 3360 hrs on it.

Is this normal for an older Kubota 4 cylinder diesel or is this a big red flag to stay away?

 

[SSdoxie]

There will always be some pressure there, some small amount of compression gases always escape. If it is blue vapors or oil dripping indicates ring blow-by.

 

[Hilbilly]

There will always be some pressure there, some small amount of compression gases always escape. If it is blue vapors or oil dripping indicates ring blow-by.

After posting this I found a site that explained the same thing so I bit the bullet and bought the machine. Of course now that I have the machine I am finding more issues but so far nothing of major concern. I don't see blue smoke but after working it for a few hrs I can smell burnt oil in the engine compartment. I'll keep an eye on the oil level and that will tell me if it is something to be concerned about. Yesterday I used it for about an hr and there was very little oil smell. Keeping my fingers crossed.

 

[HarryN]

The burnt oil smell could be a loose hydro belt slipping on the pulley. Is it adjusted correctly?

 

[Hilbilly]

The burnt oil smell could be a loose hydro belt slipping on the pulley. Is it adjusted correctly?

Harry, it looks like we both have the same machine but yours looks to be in nicer condition. I don't know anything about a SS so don't know if the belt is tensioned properly. I need to get some manuals for this machine, operators manual and service / shop manual then I will be better equipped to look after it. I just read on another thread about checking the chain case fluids and had no idea how to go about this. So some Google time and I now know where to look and will get to that tomorrow. Got to pick up some more oil too because I expect it will need a chain case fluid change.

Since we have the same machine, can you tell me what the button on the front side of the right motion control lever is for?

 

[HarryN]

If I understand your question....The left/right toggle switch on the right control would be for an attachment like a grapple. For opening and closing.
The "Button" is for continuous flow. Like a rotary bush hog mower.
I painted mine a few year back. It has about 3,000 hours on it. I was not the orig owner.
If you do not know whether the fluids have been changed .... do them all for your peace of mind.

 

[truckdiagnostics]

Hilbilly, the breather coming out of the valve cover should have short rubber hose connecting to steal tube, that will get it away from the alternator. If that rubber hose has been pushed off any oil will get in the alternator or on its belt. Also, you mentioned wanting to change your hydraulic oil. I believe you can use that oil in your chain case. Doing that may make changing your hydraulic oil to the oil you want more cost effective. You should be able to find cost effective PDF down loads for the manuals you desire. One for mine is well written and walks you through the maintenance items.

 

[Hilbilly]

Hilbilly, the breather coming out of the valve cover should have short rubber hose connecting to steal tube, that will get it away from the alternator. If that rubber hose has been pushed off any oil will get in the alternator or on its belt. Also, you mentioned wanting to change your hydraulic oil. I believe you can use that oil in your chain case. Doing that may make changing your hydraulic oil to the oil you want more cost effective. You should be able to find cost effective PDF down loads for the manuals you desire. One for mine is well written and walks you through the maintenance items.

Thanks for the info. Looks like I better get something on the breather because there isn't anything on it now and I don't want to have to replace an alternator because of something I could have prevented.

On another note. The local parts guy at the Bobcat place is the most helpful parts guy I have ever come across. So far the dealer has had every part I have needed, in stock. As much as I don't want to have to replace parts, it's great to know that if I need to, this guy will walk me through the re and re procedure and probably have it in stock. Prices seem reasonable too.

 

[truckdiagnostics]

Glad to here it is going well. I have had similar experience. I could never figure out why some manufacturers' service dealers have such good attitudes and others manufacturers’ service dealers are such turds to deal with. Is it some clause in their franchise agreement? How do they manage to get that consistence in a majority of their stores?