Is changing out the thermostat on a 2000 Honda Accord LX V6 3.0L Sedan (4 Door) something that I should be able to do myself? Or is it something that I should pay a mechanic to do?

I already have a brand new thermostat (bought from CarQuest for $15, with gasket included), but it seems like mechanic shops in my town will not use parts purchased elsewhere; they specifically want you to buy a thermostat from them. I called a local mechanic shop this morning and they gave me an estimate of $143 to replace the thermostat (parts, labor, gallon of anti-freeze, and tax). This estimate is way more than I thought it was going to cost (I expected it to be around $40-$60 for labor). If I could comfortably afford it, I would be glad to just pay a shop to do it, to make sure that the work is done properly; but I am currently struggling financially, so cost is definitely an issue. I am not especially mechanically-inclined; but I am somewhat capable of working on a vehicle, so I *might* be able to replace the thermostat myself without it being too much of a problem. Depending on the tools needed and difficulty of the job

With that said, is it likely worth it to just pay the $143 to have a shop install a new thermostat? Or is it something I should try to do myself?

And if I were to try to do it myself, could someone try to let me know what tools I would need? Specifically, the socket size(s) needed? And if I will need to move/remove any other parts under the hood to be able to access/remove the thermostat?


For the record, I've had heating issues for a couple months now, and I recently replaced two different coolant temperature sensors, so installing a new thermostat is definitely something that I need to do/get done, to see if it helps to fix the overheating. Something is causing my car to overheat on the frequent long trips I make to and from work (75 miles each way; up some seriously-steep hills, both ways), so I'm trying to figure out what the problem is, and the thermostat seems like a logical issue to address. I actually had to buy a new plastic radiator overflow reservoir tank a few weeks ago, because (while driving up a really steep hill that is about 5-6 miles long) my car overheated, and the water that flows in and out of the overflow thank was so hot that it literally melted through the plastic overflow tank and actually caused it to explode. Well, just last week, the same thing happened to the new plastic overflow tank that I just bought about 6-7 weeks ago. I ordered another overflow tank ($11) and it should be here early next week. So, the heating issue is obviously a serious concern.

Also, while thinking of this overheating issue, are there any other ideas/suggestions about what other likely problems/fixes might be? Should I do a cooling system flush? Or try something else?

And,, as always, much thanks to anyone who offers a helpful reply!

 

I typically recommend buying a Honda thermostat from the dealership.

Replacing the thermostat is not terribly difficult. It just depends on how much access you have to unbolt the housing. Take a look on youtube for changing the thermostat on a V6 to see if you can handle the repair.

Is the temperature gauge on the dash indicating you are overheating? Is the engine running poorly?

The melting of the overflow tank seems like you have an issue with combustion gas getting into your coolant due to a bad head gasket. A leakdown test would be helpful to diagnose the issue.

 

First off, thank you very much for replying to my thread!

Second, I'm thinking that you are likely spot-on with your diagnosis, as I called a local mechanic shop and asked about the cost to get a new thermostat installed, and after I described what's going on with my Accord's overheating issues, the guy I talked to also specifically mentioned the possibility/likelihood of there being a head gasket problem, after hearing that my plastic overflow tank melted/exploded. And he suspected/suggested the same problem that you mentioned in your reply, about combustion gas getting into the coolant, due to a bad/damaged head gasket.

Also, I recently noticed that my car seems to be idling weakly/having less compression while running right when starting it up, so I'm guessing that this weak/compression issue is likely due to the head gasket having a leak/some major problem?

As for the overheating, yes, my engine gets really hot and the temperature gauge goes up and maxes out quite frequently; to the point where it does it at least once, basically, every time that I drive the 75 miles to and from work, while going up one of the long/steep hills on the highway that I drive. Sometimes, it will do it 2-3 times, so I will have to pull over and wait for it to cool down, then add more water to the radiator.

Also, my battery completely died last week, so I bought a new one, and after installing the new battery, there's a now problem with my temperature gauge. The damn gauge will immediately shoot all the way up, like the car is completely overheated, as soon as I turn the key to start my car, after not having been running for like 12 hours. so the engine is obviously totally cold. It will eventually drop back down and the temperature gauge will work normally; but it only works properly for a few minutes at a time, and the needle will still continue to shoot all the way up the maxed out position every few minutes, and it will sometimes stay that way for several minutes at a time, which really sucks, because while it's stuck like this, I have no way of seeing how hot my engine is running, since the damn temperature gauge needle is stuck at the top of the gauge.

I keep meaning to disconnect my new battery for a few minutes and see if that will help to reset the temperature gauge, but I haven't done it yet. Should disconnecting the battery likely help to reset something? And if this does not fix the problem, did the engine coolant temperature sending unit (or something similar) possibly somehow get damaged from the last battery dying and/or the new battery being installed?

As for the potential head gasket issue, it seems like there is very likely a problem with mine, but it's not bad enough that my car won't start and I can still drive it around, and I haven't noticed any smoke coming out of my exhaust. So, I'm curious, are there any affordable, potential fixes that might help with a non/major head gasket leak/problem?

I know that Lucas makes several products that help with engine/transmission leak issues (Oil, Transmission, Power Steering, etc.), so I was wondering if they might make something that could possibly help with a head gasket leak/issue? I will search online after I post this and see what I can find out myself, but I wanted to ask in here while I was thinking about it and see if I could get some feedback about a potential fix for a head gasket issue from someone who may have already used something to help with a head gasket issue.

Edit: I found a product called Bar's Leaks Block Seal Permanent Head Gasket Fix that is available for $22.50 for a 24-oz bottle on Amazon with free 1-day shipping and it's got some really encouraging reviews. Has anyone here used this stuff? Is it likely worth buying and trying it out? If I can help my car to run more strongly/healthily and get some more mileage out of it, by spending $22.50 on this Bar's Leaks Head Gasket Fix, and either installing a new thermostat myself or maybe finding a private mechanic to do it for around $40-$60, I actually have enough cash to do that right now. So, some thoughts/advice on this would really be appreciated.


For the record, I am in a tough spot financially, and the mechanic I spoke to mentioned that a head gasket repair/replacement could be over $1,000, and I only paid $1,800 for my 2000 Accord LX about 2.5 years ago, so paying for a new head gasket/any major repair is just not realistic for me at this time. So, that's why I am asking about a potential temporary fix that might help with my current head gasket issue, that might at least help my vehicle to stop overheating and to be able to be be driven for a few more months and a few thousand more miles.

Is there anything worth trying that might actually help with a leaky/damaged/possibly-blown head gasket?

And should I even worry about installing a new thermostat now, with there being a high likelihood of a head gasket issue?

As always, sorry for the lengthy message. And helpful replies will be greatly appreciated!

 

I don't think the stop head gasket leak will help, especially since your engine keeps overheating. Repairing the warped cylinder head and putting in a new gasket will likely fix the problem.

You'll have to determine if only one cylinder head gasket is leaking or maybe both? It is possible that you have a crack in the cylinder head or possibly the engine block. A leak-down test can identify the location of the leak.

Also consider the repair cost for this. There are places that sell rebuilt cylinder heads that may be less expensive than taking your cylinder head to a machine shop.

When the engine temperature gets to H, the cylinder head will warp, then the gasket doesn't seal. So if you ever notice the temperature getting towards H, turn on the heat full blast to help cool the engine and get to a safe location. Something as simple as a minor coolant leak can lead to an expensive head gasket repair.

 

OK, I am probably going to try to replace the thermostat myself, as I called a mechanic at a local shop who is willing to use a thermostat bought elsewhere, but he said it would still be $120 just for the labor, as it's apparently considered a 1.5 hour job. And that's just way more than I thought it was going to cost, and more than I can comfortably afford to spend right now.

I just watched a video on YouTube of a guy who was changing out the thermostat on a 2000 Accord, but he had a bunch of aftermarket parts installed, so things looked differently than they look on mine. However, it looked like it was basically the same things I would need to do on my engine, so I think I'm going to give it a try myself here within the next few days.

I'm curious about a few things, though. So if someone familiar with this work would reply and offer some helpful information or advice, I would really appreciate it.

1.) What tools should I need to change out the thermostat? Just a 10mm socket and pliers/vice grips to remove the hose clamp? Or are other tools also needed?
2.) Is bleeding the cooling system necessary? Or, since my radiator has needed to be refilled many times lately, is it not airtight, like a normal system would be?
3.) How long should this job realistically take for me to complete? It honestly seems like it should take less than an hour, or even 30 minutes; but I obviously don't know.

If someone would reply and try to answer these questions for me, it would be very much appreciated!



Thank you very much for replying again. Unfortunately, getting some major/expensive work like that done is just not realistic for me right now; so that's why I'm trying to get minor/less-expensive things done, that may help my car to run better/cooler for the time being, and also prevent things from getting worse.

When I say that getting major/expensive work like that done is not realistic, I mean that I literally do not have the means to come up with the money ($500-$1,000 or more) to pay for something that expensive. I have no credit cards, no money saved, and no family or friends to even try to ask to borrow from anymore. So, it's literally not possible for me to come up with $1,000 or $750 right now, and it is unlikely for me to be able to come up with even $500. As I've mentioned, I drive 75 miles to and from work each way, over some serious mountains and steep inclines, and I'm spending like $250-$300 per month on gas alone. Plus, I just had to buy two new tires and get my alignment done, and that was $245. I also had a scumbag so-called friend burn me for $200 recently, and that set me back noticeably. So, I am in a really tough spot financially these days, and that's just the reality of it. Honestly, that's the main reason I don't just pay the $120-$145 to get a new thermostat installed by a mechanic, because I just don't have the money to pay for it.


I figured I would mention that, so that you're aware of my situation and will understand why I'm not asking about the more-serious/expensive repairs that you are suggesting, and that may/likely need to be done. So, if you would like to reply again and offer me some advice/information about installing a new thermostat myself, please know that I would definitely appreciate it!

 

I understand your situation.

As long as you can get to the 10mm bolts on the thermostat and remove the hose, you can swap out the thermostat. I'm not sure a new thermostat will help out if you have a blown head gasket.

Try as much as you can to carry water and keep the radiator full. Overheating the engine will eventually cause the engine to fail.

 

Thanks for the prompt reply! For the record, I do keep water in my vehicle at all times, and I currently have 4-5 anti-freeze jugs full of water in my trunk.

Also, I went and had the codes pulled at AutoZone 2-3 days ago and only two codes showed up. P0117 Engine Coolant Temperature Sensor Circuit Low Input, and P0122 Throttle Position Sensor Circuit Low Input.

I'm curious, is there a code that should/would show up for a blown/leaking/damaged head gasket? Or is that not something that there is an

And in case you were going to ask, yes, my 'Check Engine' and 'Maint Req'd' lights are on, and have been for weeks/months.

 

Maint.Req. lamp is simply triggered by miles driven since you last reset that warning lamp. It's just a reminder for oil change & I think it goes off in 7500 miles.

Check Engine is on because of the P0117 & P0122 codes which you know about. There isn't a code for "blown head gasket" - but I guess it can cause the P0117 if the liquid level gets low enough.

The 4-cyl Accords have bleed valves on the thermostat housing because that's a high-point where air bubbles can hang out. Pretty sure the V-6 engine clears the air bubbles over to the radiator as it runs, so it doesn't have a bleed screw. Just check for air collecting at the radiator cap a couple times after you start driving it. Hondas don't like to have any air in the cooling system.

You may not have to get the hose off, just unbolt the T-stat housing & flex the hose out of the way. But be prepared to clean up any crud around where the T-stat gasket fits.

 

Thanks for the replies, PAhonda and JimBlake! I haven't tried to replace the thermostat yet, but I think I'm going to try to do it this week, possibly, later today or tomorrow. I did end up driving my Accord to work and back on Saturday night and it didn't overheat, and it kept relatively cool for most of the 75-mile drive each way, but towards the end of each trip, the temperature gauge showed that it did get quite hot; probably, up to around 90% on the gauge. Which isn't good; but this was after a gradual increase over the course of a few minutes, as opposed to the manner in which it would overheat recently, where the temperature gauge would be around 40-50% and then suddenly shoot all the way up and max out the temperature gauge within about 5-10 seconds. So, it looks like the new radiator overflow tank and new Coolant Temperature Sensor that I installed last week have helped at least a little bit. I'm hoping that installing a new thermostat will help even more to keep my car cunning cooler, though.

I'm also curious about something I think I mentioned before, which is, trying out the Bar's Leaks Block Seal Head Gasket Fix. I think that it was suggested that this would likely not help my particular situation, with combustion fuel possibly getting in to my cooling system, due to a possible/likely head gasket problem. I wanted to ask, though, is it possible, or likely, that using this Head Gasket Fix could make things worse, or damage something, if there's not actually a head gasket leak/issue?

Basically, is there any risk with using this Bar's Leaks Block Seal Head Gasket Fix? Or is it worth at least trying, since it's not realistic that it will damage anything?

If someone would reply and offer me a helpful response to this question, I would appreciate it!

 

OK, someone suggested that I do a compression test on my engine, to try to see if it would detect a head gasket leak. So I wanted to ask, how can I do a compression test? Is it something I can do myself? If so, how difficult/expensive would doing it myself be? Or is it something that a mechanic shop would need to do? And if so, how costly is that likely going to be?

Also, since it seems like I do likely have a head gasket leak/issue, would anyone suggest that I go ahead and buy a bottle of that Bar's Leaks Block Seal Permanent Head Gasket Fix and at least try it and see if it helps? Or could putting something like that in my engine possibly/probably damage something?