Can't find the radiator cap 1990 Vw golf

limited info generic answer was it just a rad flush or whole coolant system flush ----max cap 10 qts is the whole system not just radiator which would be about 1 gal -check operation of thermostat --water pump and for air bound

You need a radiator. The cores are plugged. Flushing will not help and if you flushed the cooling system when coolant was filthy and rusty everything is now in radiator cores.

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you need, knife/ gear clamp,screwdriver /nut driver (for gear clamp) and garden hose
with water pressure hook up hot water is better
you can buy a can or to of rad flush but dishwasher soap works good (it wont suds up )
also rad flush kit with garden hose addapter (most kit are compatable)
1-drain existing coolant in container for recycling
2-locate heater return hose to block and cut to installed flush kit addapter
always better to reveres flussh system with engine off and rad cap removed
drain valve closed hook up garden hose and run hot tap water true system
it will eventually cove out your rad cap (surge tank) until it runs clear
know sut off the garden hose add your cleaning additives installed rad filler cap
run engine per direction on can or 10 to 15 min. sut off engine removed filler cap
open drain valve on radiator and drain out system open water from garden hose
run water until clean water run true shut off garden hose and removed cap off with
cap supplied with kit let system drain completly . repeat cleaning operation until
water runs clear
add 1 jug of concentrated coolant (will mix with ressidual water and finish filling
system with premix used recomended coolant only for your engine your freeze
point of new coolant should be above spec and will be fine
do not used pure concentrated coolant only .your ownners manual spec section will
give capacities system will hold

If it is fogging your windows, you have a leaking heater core. Dash removal is required to fix it.

It might help removing the battery. You might try installing the radiator and then the fan assembly. It may also help to remove the top piece that is mounted above the radiator, where the hood latch is mounted on.

Wait until motor is cool. remove rad cap and loosen rad drain pet **** under rad. If you can't loosen it or cant find it, remove lower rad hose. let all antifreeze drain. Close pet **** or replace rad hose. Fill with water and rad flush(you can get the flush from an auto supply store or wallmart). Run for the recommended time on rad flush bottle. Wait for motor to cool. Then drain out water. Refill with 50% prestone and distiled water.

take of the top heater hose, use a funnel to insert flushing agent connect hose and flush through.with radiator cap off.take off bottom hose to radiator to drain system,reconnect all hoses,fill expansion tank to fill system...

Need to change the thermostat and check the water pump.Make sure the belts are in good shape to.

coolant will go into the radiator,there willbe a cap indicating that its the radiator cap under the bonnet,can go into radiator overflow bottle as well but check level indicator on the side

(With the engine cold) remove the radiator cap

First drain the coolant out of the radiator in a container, either from a drain on the bottom of the rad, or by slowly removing the bottom rad hose.

Block, or pinch the top radiator hose

First, flush from the top... pour water into the rad cap hole for a while and let it come out the bottom hose.

Then, run water from the bottom, and let it run out of the open cap.

Then flush it from the top again.

This should flush the rad, unless it is clogged pretty solid.