How do i fix my yz 125 1989 water pump the water comes out the over flow pipe aswell as air

You need to advise the model .. but assuming its the CVA 40XX series ... the frist thing to check is the dispenser which has the two pipes comming out of the bottom. This can get coffee residue build up which usually causes 1 or both pipes to have reduced coffee flow. Indication that this is at fault are if the flow is uneven between the pipes or if coffee flows down the outside of dispenser. You can chck this pipework for blocages by openeing door and blowing air though the pipe extending on inside of door. The the dispenser is blocked you need to remove from rear of door and then clean out thoroughly in running water. If this pipework is not and

You need to advise the model .. but assuming its the CVA 40XX series ... here is what I would do;
1. First check is the coffee dispenser on front which has the two pipes coming out of the bottom. This can get coffee residue build up which usually causes one or both pipes to have reduced coffee flow. The indication that this is at fault is if the coffee flow is uneven between the pipes or if coffee flows down the outside of dispenser. You can also check the dispenser for blockages by opening door and blowing air though the pipe extending on inside of the door. The air should flow through easily. If the dispenser is blocked you need to remove from rear of door and then clean out thoroughly in running water.
2. Next check the pump and water path. The pump for the coffee is also used for producing hot water. So if the hot water is working normally then you can rule out the pump. If you not getting hot water then its likely to be the pump or a blockage in the flow through water heater.
3. If above OK then it's a fault with Brew Unit. Follow procedure to remove the brew unit, clean unit and test the air path through both pipes by blowing. Note: When you take out brew unit it not possible to access one of the pipes because its protected by a plastic shield. There is a manual procedure to manipulate the brew unit to expose this pipe so you can blow through it. However the likely cause is not a blockage in these two pipes but the stainless steel filter that the coffee must pass through. You will need an Allen key to remove the bolt holding this in place. Once removed you need to check all holes are free of blockage by inserting a very small wire in each hole. Alternately you can replace this part. If the filter is clogged then you should consider using a different type of coffee as some types coffees cause this problem and others do not.
I hope this helps. regards

remove and check the thermostat
have a compression test done to check for problem gasket or cracked head

Check the vent pipe, air must flow in and out of the vent pipe at all times. The vent pipe must be an 1 1/2" pipe coming off the top of the pump casing and vented outside the house, to the open air. Do not use a cheater vent, studdor vent or mechanical vents as they are not recommended to be used, they only allow air to flow one way.

The air gets into the lines on the suction side of the pump and the pipes and valves leading to it. I could write a pamphlet or chapter of a book on this topic. Anything that can let even a little air in can cause it. A quick way that can detect where the problem on about 50% of the time. When you get the water flowing as much as possible and then you shut off the pump while you watch the pump and pipes on the suction side then a spurt of water may be visible. When you fix it then less air should get in when you run the pump. Another trick is to shut off the pump and listen carefully for any sound as the slight suction in the pipes tries to draw the water back into the pool. Another trick is to use a hose with water to water the pipes, valves, pump, etc. and when you move it from place to place and if the air visibly decreases in the pump bowl then you may have found the leak.

I hope this helps

Here are some things to check. First ensure you have bleed all the air out of lines and that there is not a blockage. Then ensure the water inlet supply hose is and the water outlet supply hose are hooked up correctly. Pretty much the pool water should be going into your filter pump first. Then your filterpump will pump into the saltwater system and back into the pool. If this is correct, check the PVC pipe with the flow sensor. Its the pipe to the right if you are looking at the machine from teh front. It also has an electrical connection coming out the top of it. Ensure that the arrow on that PVC pipe is point in ths same direction as the pipe to to its left. If all that checks out, then unsrew the electrical and pull out the flow sensor and clean it a rag or a toothbrush and reinstall it. If none of this works then the manual says that you have a faulty flow sensor and intex has been out of stock for awhile. However, another to check and make sure that it is not you flow sensor (about $14) you can take some electrical tape and tape the white flap of the flow sensor to the black base. reassemble it and run the salt water system. The filter pump has to be running when the saltwater system is running. If the chorine light comes on on the salt water machine, then you have a faulty/worn out filter pump. If the machine says 90 then it is definately your flow sensor.

Did you put an 1 1/2" vent pipe? It must be vented to the open air. Air must flow in and out of the vent pipe at all times so it can work properly. I had the same issue but after removing the cheater vent from the vent pipe it solved my problem. They do not recommend using an air admittance valve, cheater or mechanical vent on the vent pipe, as it only allows air to flow in or out.

possible blocked pipe,while machine is full of water take the outlet pipe and lay this as low as possible into a bowl. if no water comes out then you have a blocked pipe. 1st if there is a filter remove drain plug and check filter. If no filter then you need to remove rear panel, Under the sump there is a large black hose, this goes to the pump. By removing the sump side of this hose with suitable tool you can check inside pipe. You may also need to check waste pipe aswell.

sounds like the raditor could be blocked or the pump is spinning to fast install bigger radiator pipes also fill it with coolant completely to the lid and also bleed the air out off system get back to me if need any more help or you have done this

Are your electric fans engaging or turning on?