****** sludge in radiator recently had hoses replace for radiator? Car is. E 46 318i. Not overheating what is the cause and how is it fixed?

Connie, Were the radiator,water pump and thermostat replaced to try and fix the over heat issue or as maintenance. Engine overheating can be caused by a lot of things, Leak in cooling system, air in system, bad rad. cap, slipping belt, faulty thermostat or installed upside down, faulty water pump, plugged radiator (inside/outside), collapsing rad hose, faulty cooling fan, leaking head gasket, sludge plugging engine water passages, poorly tuned engine, etc..
Take into a good shop for diagnoses and estimate for repair. Check the attached links,instruction and guides, Good luck
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How to Troubleshoot an Overheating Engine
Steve Litt Overheating Guide
Diagnose Engine Overheating Auto Repair Help
How to Troubleshoot an Overheating Engine DoItYourself com

Steve, there's many causes of overheating. You say you have a new water pump and thermostat, so it's obviously not those at fault.

Just a question ... you say your car is not cooling, but is it actually overheating? A faulty temperature sender unit (it screws into the engine block, usually..) can give an incorrect reading on your gauge.

If it is overheating - steam/you can feel the excess heat - is your radiator fan kicking in? Is your car overheating as soon as you drive it? Or overheating when stuck in traffic .. and the fan isn't kicking in..?

Other things that cause overheating which spring to mind include a blocked radiator and/or a collapsed radiator hose.

Hot coolant enters your radiator via the TOP hose and cools as it goes down the radiator, then back into the engine via the bottom hose. Check both top and bottom hose after the engine has warmed - sometimes a hose can become 'flat' and blocked.

Another thing that causes overheating is a burnt head gasket/cylinder head problem.

Switch the engine on and look at your coolant bottle - a continuous 'bubbling' indicates that exhaust gases are finding their way (via a burnt head gasket) into the cooling system.

Any oil in the coolant bottle also indicates cylinder head problems. Also check the oil dipstick. If coolant (because of a defective head gasket/head) has found its way into the oil system the oil on your dipstick may appear a creamy/greyish sludge.

Blocked cooling system most likely a stuck thermostat. The coolant is not circulation therefore not getting to heater core. Replace thermostat and it should be fixed

Car Overheating? Why your Car Overheats & How to Fix It

www.vikingspeedshop.com/car-overheating-fix-prevent-future/

Rating: 4.2 - ‎51 votes
Oct 30, 2015 - The biggest cause of this is a faulty thermostat that is stuck closed. ... If the radiator cap were to be at fault you most likely would see steam from boiling coolant. My car only overheats when I accelerate hard or drive hard!

Why Is My Car Overheating and What to Do? - EnkiVillage

www.enkivillage.com/why-is-my-car-overheating.html

An overheating car can be caused by many problems. ... Why Is My Car Overheating: Possible Causes .... If you do open the hood, try to do so only when the car is cooled down. ... Never open the radiator cap while the radiator is hot, as the release of pressure could lead to serious ... I wonder if my radiator might be clogged.

Common Causes of Overheating ' ASC Industries, Inc.

asc-ind.com/cooling-system.../common-causes-of-overheating/

... injury, never, ever attempt to remove a radiator cap while the engine is hot! Anoverheated engine can be caused by anything that decreases the cooling system's ...Possible leak points include hoses, the radiator, water pump, thermostat housing, ... Be sure to use the coolant recommended by your vehicle's manufacturer.

Diagnose Engine Overheating - Auto Repair Help

www.auto-repair-help.com/auto.../diagnose_engine_overheating.php

It sounds like you blew a head gasket, sorry about that.

collapsing bottom radiator hose indicates blocked radiator cores
would be time for a new radiator after you again flush out the cooling system completely
have the radiator shop fitting the new radiator do the flush as they know how to do it properly

Are you getting propper curculation through the radiator?Remove radiator cap (cold) start car and inspect, put cap back on and allow it to warm up. After the engine has reached normal opperating temperature check to see if the bottom radiator hose is getting hot.Does it have electric colling fans? If so make sure they are comming on when the engine gets hot. If not make sure all fuses and relays are OK.A radiator core blocked or restricted or dirty can cause over heating. Afaulty thermostat can cause over heating.If the heater is not working then the engine is not circulating the collant properly. and the watter pump could be no good.If the bottom rad hose does not get hot then there is no circulation and the watter pump is no good..It could be a faulty thermostat.If the upper rad hose stays cold after the engine is at normall temp replace thermostat.Do not run engine to boiling over point or serious engine damage may ocure.Incorrect ignition timing can also cause over heating. Myself I think that the bottom half of the radiator froze up on you. or the water pump is no good. Please let me know the end results.Good Luck and have a good XMASS.

The overheating is caused by the sludge. It is very easy to correct this problem. Remove the radiator cap and open the drain valve at the bottom of radiator. If possible, remove the reservoir and flush out with water. Make sure to get all sludge out of reservoir, then reinstall. Once the radiator stops draining, insert water hose (without nozzle) and turn water on. Keep the drain valve open. Run water through radiator until it runs clear. Once it runs clear, start the engine and let it run while keeping the water running through radiator. Allow engine to run until the thermostat opens up. Continue running water through radiator with engine running until the water from drain runs clear. Once you have done that, turn off the engine. Close the drain valve and refill radiator with proper mixture of coolant and water. Once radiator is filled, start engine and let circulate through engine. Coolant level will drop as the coolant starts circulating. Shut off engine and top off radiator. Fill the reservoir with the required amount of coolant. Testing the coolant at least once a year will help prevent this from happening again. Coolant should be replace a minimum of five years, less if coolant bottle specifies.

oil is mixing with coolant then only it can happen , replace oil cooler cause oil cooler it is mixing, ,and clean all hose radiator for sludge free.

that method will not work, the best way to clear the radiator is use a garden hose, take a rag and wrap it around the hose to seal it and then put the hose into the bottom radiator hose connection pipe, this will reverse flush the radiator and force the sludge out the top of the radiator,the rag seals the hose so you can build maxium pressure to back flush. having a radiator flushed by a radiator repair shop is not that expensive if you remove the radiator, I really recommend you have them clean the radiator right, an overheating engine can cause damage very fast, so a professional cleaning is worth the money.