Coolant Leak/ Head Gasket??

Hi All,

I was doing an oil change on my truck the other day when I noticed what appeared to be a tiny coolant leak, possibly coming from the driver's side head gasket. I noticed a small amount of dried up, crusted coolant right near the head gasket/ exh manifold area. It's nothing crazy, but still bothers me, especially with only having 81k on an '04 (3.4 V6). I've done a TON of water pumps on these, so I know it's not signs of a leaky water pump.

Has anyone had a similar coolant leak? As far as doing the head gaskets, anyone familiar with these/ have any tips for doing them at home?

Any advise is greatly appreciated.

Thanks,
Tony

 

If it such a tiny leak that you haven't noticed by having to add coolant I wouldn't do anything but keep an eye on it. If it gets worse it will make it easier to identify where the problem is.

 

you could always add the dye and check it with a blacklight. Make sure your clean your engine bay before you do this and don't wait too long to check it. If you have that coolant running all over the place it'll be harder to see where its origin is. Also don't rule out the possibility of a pin hole in a hose that only leaks under high pressure and when its in a certain position. But if your coolant/oil and exhaust looks good then don't fret too much.

 

If it is crusty, then it is not a continuous leak most likely. Any chance you could post a photo? As for the job itself, while it does take some time for a "backyard" type job, it is not impossible with the correct tools.

 

Thank you guys for the responses. It's definitely not a leak leak, but more a few drops that crusted over (I've attached a pic, but not too good of one).
I'm not to concerned, due to the fact that the coolant and oil both look clean, and the truck does not overheat whatsoever (I keep a close eye on the temp guage and my ScanGuage).
I was actually a tech for Toyota for 4 yrs, just never had to do a head gasket job before on one (only on a Honda Civic), therefore, I'm not familiar with the details of this specific one. I know people on here have done them before, so any specifics/details would be great, in the event that I do need to do it.
Thanks!!!!

 

That area is close to a water jacket between the head and the block. I would consider you are highly accurate that it is most likely a head gasket leaking. Obviously I won't swear to it! HaHa! If you decide you would like to tackle it, make sure you have all the proper tools. SOME of the ones you may not have (you said you used to be a tech, but didn't mention what you did) are a QUALITY torque wrench and a manual torque/angle meter. The rest of the tools needed are basic hand tools and sockets. I am not sure if they have changed over the years, but I believe the head bolts are still requiring a 14mm 12 point socket. If you don't have one in 1/2 inch drive, then get one. You will need it. Procedure is pretty basic, and if you read up on it, you should figure it out pretty easy since you have done a head gasket job before. While you are at it, I think you would be crazy if you didn't replace the timing belt, timing belt pulleys, and the water pump, as well as a new thermostat. Always a good time to do them since you will have them removed anyway. When you decide to do this, jut hit me up and I can give you information and torque specs if you need them.

 

BAMATOY1997- Thank you for the feedback- I really appreciate it. As far as the head bolts, I did talk to one of my former Master techs (I was a line tech for Toyota) and he believes it was a 12mm 12 point socket. You mentioned getting it in a 1/2" drive- will a 3/8" be too small of a drive to break those loose? And yes, I'll definitely do the tbelt and water pump at the same time, given I haven't done those yet. I've done tons of tbelts, water pumps, and valve cover gaskets on these motors, so I'm comfortable doing those, just haven't done head gaskets on them.
I'm assuming you've done head gaskets on these before? Is taking out the cams tricky/ anything special there?
Also, given the minimal leak (if that) and no overheating whatsoever, do you think it's crucial that I jump on this now, or can I just wait a while and keep an eye on it?
Thanks again! Much appreciated!!

 

Pay close attention when putting new head gaskets on. There is a left and right side and they can fit either side but are different. If put on incorrectly coolant ports get partially blocked.

I think they are all clearly marked L and R but maybe people, including experienced mechanics, space out and put them on wrong thinking the left side is the passenger side (American cars) because they are working from the front facing the rear when in fact the left side in the driver's side for American cars.

 

I have read a few good write up on this, and its not for the faint of heart, besides on here, do a google search on head gasket replacement on Toyota 3.4, for more info.

 

If you have coolant in the oil..then you need to be worried. Otherwise i think your fine for now.

 

A rule of thumb that many techs follow is "if it drips, get it fixed" If you have a small amount there and it is not actually forming drops on the floor overnight, then I suggest you take the next few weeks to read up on procedure and gather your parts. It will allow you time to get prepared. Have a backup vehicle just in case you need to run to the part store for something small. Your friend is right, I forgot they ARE 12mm bolts. I work on so many engines that sometimes I get a number mixed up. I would still suggest getting it in 1/2 inch drive, and get a good breaker bar. You will need it. Otherwise you will wear yourself out trying to loosen then, and using a 1/2 inch breaker bar will make setting your torque angle easier. Not to mention many 12 point sockets in 3/8 drive will break on a head bolt.

Since you have already done timing belts and the like, this will help you. You won't have to worry about that part. Removing the cams is not difficult. You should mark each of the cam bearing caps for position though, because they are bore-fitted and if you mix them up it will cause problems. After removing the camshafts get prepared to remove the lifter/tappets and their shims. Each shim is measured to properly fit that particular cylinder's intake and exhaust valve. Since you will need to celan the surface of the head, get you 2 egg cartons and mark each egg hole for a specific valve. BEFORE removing the head, but after the cams are removed, take out each lifter/tappet one at a time and place it, with it's shim, in the marked egg hole. This will allow you to be 100% sure you reinstall into the proper valve when reassembling. Other than that, a head gasket replacement job is pretty basic once you get to the heads. Make sure you get a head gasket KIT! Not just the head gaskets. The kit will come with all the smaller gaskets that you may, and probably should, need to replace during a head gasket job. Also make sure you replace all of the head bolts. Do not EVER reuse one of these head bolts!!!!!

 

Thanks again for the great input! I truly appreciate it and will probably hit you up for more when it comes time to get it done. As far as the heads themselves, since there has been no overheating whatsoever, do you hink I can get away with just putting a straight edge on heads/block or do I need to take the heads in to get checked/resurfaced? I know when I was at the dealer they always said that there was no need for that if no overheating existed. And in your opinion, should I just tackle the job already or can I just continue to keep a close eye on it as I have been?
Thanks!

 

I agree with the dealership, however it is always best to err on the side of caution. Perhaps you can find a local shop who can check the heads for straightness and evenness.

As I mentioned, it is a hit or miss on when to do this job. It could be fine for the next 12 months, or it could blow out in 2 days. I think since you already see a problem, the best plan would be to start getting the parts and plan a time when you will have a couple of days to down the truck for everything.

 

there is some really good write up with pics on 4runner web sites... they are our cousins.....
and I think I read you need to be careful about tightening down the bolts.
there is a specific order and torq ... tighten too much or little and it will leak.

 

Do you know which 4Runner website(s) I should refer to? I have all the specs and what not from the FSM (thanks to TacomaWorld Forum), but a write up w/pics would make things soooo much better.
Thanks!

 

ok this is what I had remembered........ forgive a old man... links were here...

and this good luck,,,,,,, i am just way to back yard to even think about something like this........

 

Yeah, as mentioned before either here, or in another thread, these head bolts are called "torque-to-yield" bolts, which means that they actually stretch microscopically when at the proper torque. You tighten them to a low torque, then do what is called torque-angle where instead of tightening up to a set torque, you turn them a specific number of degrees using a torque-angle meter. You want to be as exact as possible, and I will go over all of that with you when you are ready.

 

If you don't have a torque-angle meter using the method described in the FSM should give the same results:

 

Thanks again everyone! Very helpful information. As far as the torque to yield bolts and the torque angles, I'm well familiar with that info. I recall doing a head gasket on a Civic when I was in high school and not knowing any better, reused the head bolts. Let's just say that whole job proved pointless not too far down the road.
I've decided that since everything is still checking out fine for now, I'm not in the biggest hurry to get the job done. I'll start saving for the parts for when the time comes and keep a close eye on it in the meantime. Luckily, my fiance's dad has a spare car and garage space for me to use when the time comes to put my truck down.
If any other bits of info or tricks pop up that may help, please feel free to let me know. I appreciate all the input.
BAMAToy1997- Would you mind if I picked your brain a little more when the time comes to do the tear down? Again, the only thing I'm intimidated by is removing the cams..

 

well one thing I would do, since you have to remove everything, if there is a place on the island that cleans fuel injectors I would have mine serviced.