Can I find a diagram of the location of the 680 hydraulic oil filter on an 83 model backhoe

The cookie cutter answers you are getting here are probably 'Suggested Answers', they are a total script based guess on words in your search, so ford, turbo backhoe and timing. They are listed by number of relevant words found.

I have been with this site since the beginning and would say that heavy equipment is a little used section and as far as I know we have no experts in it. Google is showing me videos, but if I was crafting the search query properly it would be a little more specific, 'ford model backhoe timing (of what part, injection, valves, hydraulics etc?).

A workshop manual is the best way, or head over to the JustAnswer site in this link, plus there are more specialist heavy equipment forums that are bound to have techs as members.

https://www.google.com/search?q=turbo+ford+backhoe%2C+set++timing

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To remove, clean, and replace the hydraulic oil filter on a Fiat 411R PTO unit, you will need to follow these steps:

1. Locate the filter: The hydraulic oil filter is typically located on the side of the PTO unit, near the bottom. It is often mounted to the side of the unit with a bolt or a clamp.
2. Prepare to drain the oil: Before you remove the filter, you will need to drain the hydraulic oil from the PTO unit. To do this, locate the oil drain plug or valve and place a drain pan underneath it. Then, loosen the drain plug or valve to allow the oil to drain out.
3. Remove the filter: Once the oil has drained out, you can remove the filter. To do this, you will need to loosen the bolt or clamp that holds the filter in place. You may need to use a wrench or pliers to do this. Once the bolt or clamp is loosened, you can carefully remove the filter from the PTO unit.
4. Clean the filter: Once the filter is removed, you will need to clean it. To do this, you can use a degreaser or solvent to remove any dirt or debris from the filter. Once it is clean, you can set it aside.
5. Replace the filter: Once the filter is clean, you can install the new filter. To do this, simply reverse the steps you used to remove the old filter. Make sure the filter is properly seated and tightened down, and then refill the PTO unit with new hydraulic oil.

It's important to follow the manufacturer's instructions when replacing the hydraulic oil filter on your PTO unit. If you are unsure about any of the steps or have any questions, it's a good idea to consult the manual or contact a mechanic for assistance.

This is not a quick fix. Check fluid levels as the switching is hydraulic. You may need to consult a transmission expert if the synchro is failing.

The machine's Power-shuttle gearbox features four fully synchronized gears and electro-hydraulic switching between forward and reverse. For better balance, the transmission is mounted directly to the engine.

https://www.volvoce.com/-/media/volvoce/global/global-site/product-archive/documents/04-backhoe-excavator-loaders/04-volvo/v-bl71/v-bl71-bl71-plus-21c1002689-2010-04.pdf?v=HSEyPw

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https://www.google.com/search?q=Volvo+BL71+Backhoe+Loader.+It+is+jumping+out+of+gears

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the hydraulic filter will be either in the top of the hydraulic oil tank or next to in as a spin on filter
you should change it if the code has come up

some hydraulic units use a flow rate valve in the bottom of a ram to stop the operation in the event of a hose failure
it effectively locks the oil in the ram to stop what is raised from free falling and becoming dangerous
Talk with the service dealer to see if you have such a valve and how to release it after repairs are carried out

It sounds like there may be a bit of air in the hydraulic system. You probably have a seal leaking. Be sure the oil resivore is full.

BLOWN HYDRAULIC SEAL... REPLACE HYDRAULIC SEAL...

It depends a little on what the temperature is outside. I think I normally run a 10w in my backhoe.

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1 - a tank of the hydraulic booster of a steering; 2 - a plug mouth oil-jellied; 3 - a tank of a working liquid of a braking system and clutch; 4 - the assembly block of safety locks and the relay; 5 - an air filter; 6 - a windshield washer reservoir; 7 - the accumulator battery; 8 - the identification tablet; 9 - a measuring instrument of level of oil; 10 - an expansion chamber of system of cooling.

Ford Focus engine diagram Ford Focus engine diagram - turbo-diesel of 1,8 l Endura-DI Ford Focus engine diagram - turbo-diesel of 1,8 l Endura-DI

1 - a tank of the hydraulic booster of a steering; 2 - a plug mouth oil-jellied; 3 - a tank of a working liquid of a braking system and clutch; 4 - the assembly block of safety locks and the relay; 5 - an air filter; 6 - a windshield washer reservoir; 7 - the accumulator battery; 8 - the identification tablet; 9 - a measuring instrument of level of oil; 10 - an expansion chamber of system of cooling.