Ford 4830...air...hydrualic... fuel questions

Been working on the old thing some, and I've got lots of little things going on. First, the air filter light comes and goes, and usually stays on, even with brand new filters. So I'm guessing it the air cleaner restrictor switch. Is there anything about it that's serviceable or does it just have to be replaced? Is there anything else that it could be?

Second, it has the dual/auxiliary hydraulic system with the two filters, one engine mount, and one mounted under the left foot rest. Local dealer has been selling the same filter for both he last few years. I talked to another dealer at the end of last year and he told me they were actually suppose to be different filters. I've looked online at parts diagrams and can only find the one for the engine mount. I know the same filter will fit both, just curious if could hurt anything in the long or does anybody know the part number for both filters?

And third, the the fuel gauge only works about 10% of the time. I'm guessing its the fuel sending unit but was curious if anything else could be causing it? If it is the sending unit, how hard is it to change and is there any tricks to it? Found one on fleabay for about $30 cheaper than the dealers price...

Probably have some more questions as I get into some more little things. Thanks in advance.

If the air filter indicator stays on after you've changed both the inner and outer elements then the switch is probably bad. I'd disconnect th wires and do a continuity test on the switch with the engine not running, then again running. If it's closed it's probably bad..
The hydraulic filters are supposed to be D5NNB486-CA on the main pump and D5NNB486-EA on the engine pump. Aside from one inch less length on the EA filter to clear the manifold on the 4 cylinder tractors, it is the same filter. I generally use the CA rather than the EA filters wherever I can because there is more filter capacity there but at the end of the day as long as you keep them changed before they plug up I don't think I'd worry about it. Use whatever one you have. The pump capacities are roughly the same anyway so they can well survive on the same smaller filter. You may also find that the longer filter will work on the engine pump of that tractor but I can't say for certain. It will work on the 3 cylinder engines.

The fuel gauge could be a power supply problem or more likely a ground problem. Make sure there is a good ground from the sender ring to somewhere on the tractor chassis through the harness. The plastic tank obviously provides no ground path. The sender is located in the top of the tank. It's accessed by removing the instrument cluster, cleaning out the dirt and birds nests on top of the tank and it should be there... IIRC, there is a lock ring/tab that needs to be depressed and turned to get it out, then lift the sender clear. Generally a bad sender will register open or will not change resistance when you check it with an ohm meter...
Should probably range from 50-250 ohm.

Rod

So far as I have ever encountered, the longer hydraulic filter will work on the engine mounted pump unless the tractor has horizontal exhaust. NH in its infinite wisdom has superceded the short filter to one that is a little longer and won't fit horozontal exhaust tractors, or so I hear from customers. We now stock a Fleetguard filter for that application.

I know the long filter will not fit on the engine pump of a 7710 because it won't clear the manifold... at least not easily. It's a long time since I tried it to be quite honest. Other models it may well fit.

Rod

The long one will fit both places on my 4830. That's what one dealer has been selling me for the last 3 or 4 years. Another dealer started telling me that there was two different filters, so I was more curious about it than anything.

On the fuel sending unit(or float, that's what the online parts diagram is calling it), the parts diagram is showing 2 different ones, one for $104 and the other for $41(Messicks prices). Local dealer priced it at $86. Any idea as to determine which one I need or what's the difference in them? Messicks has been a few bucks cheaper on every other part I've priced with them so I'm guessing the local dealer prices the cheaper one to me. I'm going to give them a call tomorrow and try to see if they'll tell me which one it is.

Thanks for all the help.

Not sure I had ever encountered that. Must be I just grab one of each, which I usually do. When I was wrenching more owners of 3 cylinder tractors paid for basic service than owners of 4 cylinder tractors that had real jobs to do!!