Oil comeing out of gearbox breather holes

[andyspain]

Hi Gents, Got a problem with my hydraulic/gearbox oil. It's being forced out of the two breather holes of the screw down filler cap, just behind the seat. Must say it looks a bit bubbly, seems to me there's air getting in somewhere. Is this the reason it's being forced out? Is this why I have to wait 10 min until the engine temperature rises to normal before I can use the front loader? Seems to be a long time, cold the front loader wont lift at all!

 

[JohnS]

Sounds like you have a air leak in the suction side. It will certainly cause hyd overflow out the vent. You will need to check everything from suction screen in tank to and including the hyd pump. The first thing to do, because it is the easiest, is to just tighten all the fittings. You can also take off the elbow at the pump and check that o-ring. If you see any hyd oil on suction line, after it has been sitting, it could point you to the leak. The hard line has been know to get hairline cracks, especially in stressed areas. The cracks can sometimes be small enough not to drip, but they will still be big enough to draw air in.

After the easy checks, start at the screen. Make sure it is not plugged. Clean if neccessary. It would be a good time to flush the tank and check for metal particles.

If it is still an issue, the next choices are replacing the hard line (incase it is a hidden crack) or replacing/rebuilding the pump. If you might have stressed the pump at any time, from having the tractor running with the quick disconnects seperated, I'd replace it.

I had this foaming issue last spring, and after eliminating everything else, it was the pump.

 

[greg_g]

These units are shipped with el cheapo motor oil, ostensibly for preservation purposes during shipment over salt water. It's become standing policy to drain every drop of Asian fluid out of the differentials/transmission/engine/hydraulics/cooling system, and replace it with quality fluids available on the local economy.

I recommend you drain and flush the hydraulic system, and refill it with a quality non-foaming ISO32 hydraulic fluid. The non-foaming part is VERY important. Drain/flush instructions can be found with a simple search of the forum, as this topic has been discussed on several occasions.

If you've got the hex shaped vent/fill plug, you might have some holes plugged with grit. I am pretty sure mine had more than two. I soaked it in diesel fuel for a while, then blew all the vent holes open with compressed air.

//greg//

 

[JohnS]

Andy,

Greg has a point about the oil. I assumed that this was a "new" condition. The non-foaming oil is important, but might not be the main culprit here. If you are getting foaming immediately after starting, it is probably not the oil. Remove the fill plug after the tractor has set. Fill if neccessary, and verify that the oil is not foamed. Start the engine and watch with a flashlight. If you seeing it is already foaming or foaming shortly after it started running, most likely a leak. If you see it is foaming, it will rise fairly quickly.

I ran the original oil for about 20 hours. This included some fel exercising. Foaming was not an issue during that time. I do believe it would be, if run for significant time, ie with non-foaming oil.

 

[andyspain]

Thanks gents. I think I may have a pump problem and I'll tell you why, perhaps I'm wrong. Having taken a sh*´ñ load of good information of this site to build my tractor the guy who put it together with me ignored the part about not attaching the fel until the oil had time to circulate through the tractor system and hence lubricate the pump. There was a horrible nose from that area soon after start up and he quickly switched off the engine and disconnected the fel line. This making the circuit much smaller, allowing the pump to pick up oil and lubricate itself. However, I think it was already too late. What do you gents think?

 

[JohnS]

The pump is self lubricated and as long as oil was in the line, feeding the pump, it should have been OK. Possibly the quick disconnect was not seated fully and the pump was dead headed on start up. In any case, given that noise, I agree you should start at the pump.