Do u have to take the radiator off to change the spark plugs

It might be a clogged up radiator, in the car accessory store you should be able to find a product to clear the radiator.

This could be several possible causes. If possible I would find out what the spark plugs looked like when they were pulled from the engine. Since you had the radiator changed assuming that diagnosis was correct for the overheating you may or may not have more severe internal problems with the engine. Start with what the spark plugs looked like and possibly what the present spark plugs look like.

change ignition module

if it does not start while only turns, check if fuel comes out from pump ,also check ignition ,spark plugs good connection.

Recheck the firing order; 1-6-5-4-3-2

On the distributor passenger side radiator to fire wall. 2-4-6-coil
On the distributor drivers side radiator to fire wall. 3-1-5

Cylinder passenger side radiator to fire wall. 2-4-6
Cylinder drivers side radiator to fire wall. 1-3-5

Good luck and also check the distributor cap again for proper seating.

90000 km service includes changing.spark plugs,oil and oil filter,gearbox fluid,brake fluid ,air filter and fuel filter if needed,a full safty inspection.and the most important timing belt,and while your doing the timing belt you should do the water pump.

Platinum plugs are good, but you may have to replace the one that is back firing. It sounds like you may have the the firing order mixed up causing detonation. Two or more if your spark plugs may be firing at the exhaust stroke, rather then the compression stroke. The firing order is 1-2-3-4-5-6 and on the passenger side you have 1-3-5 ( 1 ) being towards the radiator and on the drivers side  2-4-6 ( 2 ) being towards the radiator. The distributor cap should be labeled on the inside as to the #1 spark plug wire. The cap rotates counter clock wise and the #1 should be the drivers side towards the radiator. Good luck and hope this helps. Keep me posted, be glad to help.

You will have to remove the fuel tank to get to the spark plug. Not that bad of a job...2 seat bolts,tank strap and the radiator shroud bolts and fuel petcock. Thats it! good luck!

there would be salt formation in the radiator which would turn the engine off and also may be the spark plug would be weak so try to clean the radiator and change the spark plug also.