I have a 2001 Nissan Pathfinder LE with 140,000 miles that has been overheating. We have replaced the temperature regulator, replaced the radiator, and bled all the air pockets out of the system. From reading blogs, the next step would be to replace the head gaskets (which would most likely fix the problem but not for sure). If the dealership does the work, we are guessing the repairs to cost abvout $5,000. Keep in mind the car is worth about $3,500 in working condition. My husband has considered purchasing an engine hoist / engine stand and doing the work himself or just replacing the engine himself in our garage. He said the project sounds fun. I have enjoyed my car for the last 10 years and still think it looks decent but am worried this is too big a project. Keep in mind that I am pregnant with twins and just want a reliable car in the near future. Should my husband have fun, or should we just throw in the towel and buy a new car?
Well, your husband could have all the fun he wants, but;
Have they pressure tested the engine, analyzed coolant and oil? How did they decide to do a head gasket job? How is the water pump and was it ever changed. Sometimes they corrode from inside without leaking out.
I would not put $5K in this car, also putting an engine in newer cars is pretty involved with electronics and harness issues. Has your husband done any similar projects in the past? Does he have all the tools and also some help? Also this is going to take a few days, what engine is he going to get.
I think you are all over the map.
At the end of the day if you & the future twins don’t feel safe and secure in this car, then you have to move on.
Before he tackles this job…make sure it’s the head gasket. This vehicle is NOT known for head gasket problems. Although I’m sure they have happened. Are you hearing a gurgling sound at all???
This engine is the 3.5L. It has a timing chain. It’s a complicated job. It’ll probably take a good experienced mechanic a full day. So for a back-yard mechanic then double that amount.
I’m not convinced it’s a head gasket. I suspect a bad water pump.
If want to fix it and your husband doesn’t want to do it…Find a good local mechanic…Dealer prices are too high. And this is NOT a super complicated engine to work on that only the dealer knows about.
The only way that a head gasket should cause overheating would be if there’s a breach. This breach could be external leading to coolant dripping on the ground, the coolant level becoming too low, and the engine overheating because of that.
The other breach would be if the head gasket is breached between a coolant passage and a combustion chamber.
There are a number of tests involved to determine if a head gasket is bad. Compression test, cooling system pressure test, hydrocarbon test of the cooling system, etc. I would do those before blaming a head gasket and possibly tearing into an engine or replacing it when it’s not necessary.
Head gaskets are frequently misdiagnosed as the cause of overheating and the internet perpetuates this diagnosis.
What are the reasons for overheating? Loss of coolant? Temp gauge pegged out? Dripping coolant on the ground? Has the cooling system pressure cap been considered as a cause?
This could be very simple to fix. Does it overheat primarily when going uphill at highway speeds or at elevated highway speeds (over 65 mph), then all you would need is a new radiator cap.
Give us the circumstances when the overheating occurs.
Other posters are correct, you should have a much firmer belief that this is a head gasket problem. You should have oil in the coolant, coolant in the oil, white smoke out the tail pipe or some other definative symptom of a head gasket problem. Overheating isn’t a good enough reason to implicate a head gasket without something else.
Perhaps a hose has collapsed internally blocking flow? The new radiator is bad? A weak water pump is more likely than a bad head gasket. Get a really good mechanic to evaluate this car before tearing apart the motor or switching out the motor.
Debris and gunk from years of use could be clogging somewhere reducing flow. How often has the coolant been changed over the years? Perhaps there is some sort of super high pressure purging process to clean out the passages in the cooling system.
By temperature regulator, I hope you mean thermostat. Also, as mentioned, there’s the water pump, and radiator cap. I’d also like to add the possibility of a weakened lower radiator hose that collapses when it tries to pull cool water in from the radiator. This has been observed in many cars of all makes and models. Many sources say that hoses and belts should be changed out every 4 years. Personally, I’ve observed many last much longer, but some can leak and burst without warning. Also, if the engine block has crud in it, it needs to be thoroughly flushed.
As also mentioned, a head gasket is easy to diagnose when it goes bad. Tossing up your hands and saying, ‘There’s nothing else, so that must be it’ is a good way to separate you from a lot of money unnecessarily.
What are ALL the symptoms here? Overheating is one… The reason the guys are pressing the issue of whether it is a Head gasket issue or not …basically determines the future of this vehicle…bec if it IS a head gasket…the mechanical repair of the engine will exceed the vehicle value…and we know your next step is possible engine replacement…that’s why everyone is “up in arms” about it.
OK…so it overheats…But…Riddle Me this Batman:
Do you need to add coolant often?
Did this engine SEVERELY OVERHEAT at any point in its life…like driving it w steam shooting out the rad
Does the radiator “spit up” coolant into the overflow reservoir?
Does your Oil look like Chocolate Milk?
Do you see engine oil in the Coolant or visa versa?
Do you have PUFFY White clouds of smoke billowing out the tailpipe whether engine is hot or cold?
Does coolant just seem to disappear with no other obvious leaks?
Are your radiator hoses…really hard…as in feeling over pressurized?
Does the engine run smoothly or does it have a misfire
Answer these questions for us…it will help us to determine if you are looking at a bad head gasket/s…
If it is a Head Gasket or both head gaskets and all seems to be lost on this engine…BEFORE you go to yank it out because of a potential Head Gasket issue… Buy a bottle of Blue Devil ($60) and PROPERLY install it in the engine…see what you get…It just may repair the gasket issue (IF you have a gasket issue lol) since the only other thing you will do with this OE engine is yank it out to replace it instead of repairing the head gaskets mechanically… Basically use the Blue Devil as a last ditch effort (which it will be)…to fix a head gasket issue without massive financial investment… It actually works…and works very well. Blue Devil looks like Windex…but when it finds a leak in the system…it forms a sort of Hard Water Mineral Deposit…Hard as a rock…and it works…it will find any leak and STOP IT… Thus repairing the failed head gaskets… ALL A LAST DITCH EFFORT…So you dont have much to lose but a lot to gain…PERFECT opportunity to “Make a Deal with the Devil”
BE AWARE!!! WE HAVEN’T DETERMINED IF YOU HAVE A BAD HEAD GASKET/S YET…
Let us know…these are important questions