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 of 1 people found this 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.


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 of 1 people found this helpful.

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

Some body talking right ill sale him prise is right.

It older car

Your Answer

Add photo

Related Questions

  • why is my car still overheating? 8 answers

    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.

    1988 Nissan 300ZX


    Maintenance & Repair

  • Why is my 1988 Nissan ZX car overheating 6 answers

    My water pump went out and I had a new, not rebuilt, water pump put on, also new thermostat, all new belts including timing belt and had the car tuned up, the first day that I drove it it I noticed th...

    1988 Nissan 300ZX 2 Dr Turbo


    Maintenance & Repair

  • my car is smoking 4 answers

    I have a nissan 300zx 1989 non-turbo it has over a 100k miles, one of my lines connecting to the radiator blew and I replaced and now when I drive it white smoke comes from the exhaust and the hood. W...

    1989 Nissan 300ZX


    Maintenance & Repair

  • my car will only shift into gear when car is off 10 answers

    I have a 1988 nissan 300zx turbo with a manual transmission. It was driving fine until I had it sitting for a few months. Now when I turn the car on it will not shift from neutral into any gear unle...

    Nissan 300ZX


    Maintenance & Repair

  • why does my car only start and run for 5 sec then stop, but start again 7 answers

    Car has sat for awhile, used jumper cables to start it, drove it for 20 min then battery died so i went to jump start it again and 1 simple mistake i did was put the positve cable on the negative s...

    1986 Nissan 300ZX 2 Dr 2+2


    Maintenance & Repair


Looking for a Used 300ZX in your area?

CarGurus has 131 nationwide 300ZX listings starting at $3,995.


Search Nissan 300ZX Questions

Nissan 300ZX Experts

#1 Tom Demyan
Tom Demyan
Reputation 450
#2 Jamie Staples
Jamie Staples
Reputation 300
#3 dandyoun
Reputation 240
View All

Related Models For Sale

Used Nissan 240SX
9 listings
Used Toyota Supra
54 listings
Used Ford Mustang
721 Great Deals out of 44,996 listings starting at $1,500
Used Mazda RX-7
66 listings
Used Chevrolet Camaro
350 Great Deals out of 31,370 listings starting at $2,500
Used Chevrolet Corvette
209 Great Deals out of 22,044 listings starting at $2,500
Used BMW 3 Series
1,020 Great Deals out of 31,286 listings starting at $975
Used Nissan 200SX
16 listings
Used BMW M3
28 Great Deals out of 1,316 listings starting at $4,990

Used Cars For Sale

1996 Nissan 300ZX For Sale
6 listings starting at $3,995

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.