why is my car still overheating?


Asked by Jul 27, 2013 at 11:40 AM about the 1988 Nissan 300ZX

Question type: Maintenance & Repair

my 88 300zx nonturbo's upper radiator hose blew a hole in it from a dry-rot. flushed the cooling system, rplaced the upper raidator hose and the car is still overheating.

8 Answers


Have you checked your thermostat? How old is the water pump? How old are the other hoses? Could one of them be internally collapsed? How old is the radiator cap?


couldn't tell you how old all the stuff is. bout this car 2 months ago. except for theupper hose that blew and some of the smaller hoses that have some dry-rot near the clamps the rest of the radiator hosing looks good. radiator cap seals still look good, but some bent spots on the inner metal lipping. i'm attempting to take off the front end to take out the thermostat and put a new one in. i just didn't wanna do all that work and it still overheat, but as old as the car is and not knwing whats been replaced/updated on it it's probably pretty old.


Ok you have a great car for a project and a lot of work to get it reliable. But don't fret it's not that hard. That motor is an interference motor. That means if the timing belt breaks or jumps time you will be pulling the heads off and doing a valve job because some of them will be bent. If it was mine and I did not know when the last time the timing belt had been replaced that's where I would start. While you have it apart replace timing belt, water pump, thermostat, radiator cap and all the hoses. This will cover most of the stuff that tends to go bad at that age. Seems like a lot but you will be thankful in the long run and could trust it not to have some sort of major failure due to these items being old.

1 out of 1 people think this is helpful.

Your thermostat is stuck. 2 bolts, 10 bucks, gasket sealant & your good to go. You can run eng w/o a thermostat, your temp gauge won't work is all.

Michael Tutty

Dandyoun has the only correct answer. Do the lot. That rubber timing belt is likely OLD if the rad hoses are old enough to dry rot. If you are very lucky, you will only be dong a head rebuild if it lets go. More than likely you will be searching out a new engine. When the valves and piston connect, it can hole a piston, break a connecting rod, screw up bearings, and all sorts of other damage. It will cost to have it all done, likely somewhere in about the $1,000 mark, but it is a HELL of a lot less money than the simplest of repairs if that belt lets go. Regardless of mileage, timing belts need doing every 5 years. They are rubber and get brittle as well as stretching. While the front of the engine is off, do the water pump (require as part of the job on that engine), the belts, all the hoses, change the rad cap, and have the radiator flushed. If you are not certain of the condition of the rad, slap a new one in at the same time. These are great cars, but they are maintenance intensive.

1 out of 1 people think this is helpful.
Scottie Mccluney

I have a 300zxtubo 1988 run good just put a altnater on the car run good need some work on it.i i just foundout tonite found water pump licking cant keep water in rader but comeing from oppister side of hose by rador smoke look like comeing from up there by termstite over from water pump. it tIme for Me too change timimg belt been drivering 7 year 2water pump if its gone checking in the morning. Time for me put little money in to keep up the maintance. It a real collect idom.might sale black with are reems 5 speed its my second 300zx it not regular.704 7808903

Scottie Mccluney

Some body talking right ill sale him prise is right.

Scottie Mccluney

It older car

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