4.0L V6 with bad head gasket (repair or replace?)

Thanks. Oh I think I start wrenching over the next few days. You pretty much got all the questions and answers covered on this thread but I'm sure some stuff will come up that will have me scratch my head. When I'm stuck I'll call for.

 

Quick update: Today I'll take the timing cover off etc. Had to use a shop-vac frequently to clean lots of sand and dried mud around the intake as I took things off the engine... guess I'm not much of a city driver. I don't have to be in a hurry with this job as I'm patiently waiting for the CTA head bolt wrench. Amazon was or is out of stock so e-bay it was and it takes a while to get to the edge of nowhere up here lol. So far I had no problems following instructions as discussed earlier on this thread. I just hope not to find some major warping on the head but no matter what I'm going to slap this all back together and see what happens since this motor just loves to run (the darn thing fired right up as I went to thake the harmonic balancer bolt off ).

 

Nice progress! Remember, just make sure the CTA tool is all the way down in the bolt head before removing and you will have no problems.

 

I just got informed that my CTA tool is still in Kentucky at the global shipping centre.... lol... I guess I can take the time and turn that engine over until the colored chain links on the timing chain match up with the colored cam chains links.... I have it all matched with the notches and marks but not with the colored links... don't know how many times it takes to turn the engine over and just left it but now that it takes at least one more week to get that tool and I have to keep heating the shop regardless I might as well do it before I take the stuff off. Also clean everthing that needs to be cleaned and heck I'm going to change out the cv axles since I have new ones laying around ...

 

That stinks about the tool being delayed. I had a similar problem with my OEM parts from an online dealer.

Anyhow, in short, I believe the number of rotations are in the teens. I'm sure someone here will comment with the exact number. It turns out that I was lucky when I took mine apart. Meaning, I don't think I had to turn it more than a few rotations to get all of them aligned.

However, I am going to boggle your mind. Your engine is already "timed" since you have never messed with the timing. The reality is every two rotations of the crankshaft will put the cams in alignment with their marks on the VVTI gears, the orange marks on their chains, and the marks on the front bearing caps. This is all you need to be concerned with. The SM never refers to the yellow mark on the main chain during engine disassembly. It just refers to it being at TDC.

After saying all that, you will most likely still make sure the main chain and its yellow mark is matching the TDC mark on the crankshaft just to be sure. After all, I did that too.

 

Well, I finally got that tool today... ordered it Jan 17 or 18 after Amazon told me they could not deliver... the place I bought it from via e-bay send it ot the next day but from there on it was slow going... uphill all the way on icy roads I guess.
Anyway, got the heads removed and will bring them to a machine shop tomorrow. All looks well and clean to my untrained eye but I sure did not like to see some sand falling onto some pistons and sticking to some cylinder walls. Not much carbon to clean anywhere so I guess I just follow cleaning instructions from earlier posts here but leave that little bit of carbon alone. I'm thankfull for this thread that's for sure, lots of info and links. I'm kind of stoked to have gotten this far without breaking anything.

 

It's good to hear that you got the CTA tool and the heads off. I wouldn't stress about the dirt and sand during the removal of the heads. I tried to vacuum the area before removing them but the same thing happened to me. Once you get to cleaning the block surface, you can vacuum the cylinder block area including the pistons before rotating the crankshaft. After the initial vacuum, I rotated the crankshaft over a little at a time so that I could wipe off the cylinder walls and inspect them. I put some oil on a lint free towel to wipe any dirt off of the cylinder walls. Do your best to try and minimize debris getting into the cylinders. I plugged up as much of the coolant ports as I could during the cleaning process. In the end, I was able to vacuum out any debris that got down into the cylinders or the coolant ports.

 

Got the heads back today. They took .004 off both and are now clean and ready to install. I'm going to get on it tomorrow or the day after. It's snowing here like a bastard so I'll end up plowing out the neighborhood tomorrow and maybe I just have a beer after ... Anyway, I have everything here to get on with this job and can't wait to see that truck running again.

 

So far so good. Tomorrow I put the timing cover back on. Heads, timing chains, exhaust manifolds etc. installed without a hitch. Actually I installed the heads with the exhaust manifolds pre installed because there are enough tough to reach nuts and bolts and I did not want to add more. I will do a couple dry runs to put that cover back on just to be sure it's not turning into a shit-show with that sealant on there.

 

Good to hear things are going well. Smart move on putting the manifolds on the heads first.

 

I ran into a small rubber problem. The gasket kits I have do not include a proper fitting oil pump O-ring... I thing it's the one listed below. Went to our Toyota dealer and I will not get it before end of next week. I also ordered a kit with crank seal from another parts dealer but that o-ring also does not fit... wow... This is what happens if you are a rookie at this. I should have checked out the seals weeks ago after I took things apart... live and learn..
Engine Oil Pump Pickup Tube Gasket - Toyota (96722-24030)

 

Interesting. If you’re referring to the gasket on top of the oil pan and between the timing cover, that came part of my valve grind kit.

 

yeah, that's the one...

 

Hey zguy1... my truck is running like a song!... for now anyways. Last Saturday I had enough of this waiting around game... seal or not I just installed the old one with a little fixer upper (it was cracked) and went on to get this job over with. Truck started up perfect, I did pull the fuel pump relay to get the oil flowing first, and no leaks so far. Idles perfect, no coughing or rough rpm. I do have a check engine light that I will address tomoorw but it was there before I did the head gasket.
Anyway, a big Thank You to you for posting your repair and progress at the same time thank you to all the members that helped you along since it also helped me along big time.
Cheers to you and Tacoma world!

 

That's good news @Borealis. Glad to hear you got it running. I just tried to document what I did especially since I got so much help from the folks here. If I can help one person with this thread, then I feel it was worth it.

 

You succeeded ! I got totally inspired to do it myself after reading your thread. It safed me 175 per hour in a shop up here.. plus it's very satisfying to even just try it and give it your best!
Cheers

 

I have gotten a few inquires about how the repair is going so I figured today would be a good day for an update. It's been about 5,000 miles and she is running great.

Today I hit 300k. I guess technically I saved her from retirement by replacing the head gaskets.

 

Thanks for the update. That’s awesome! No sign of timing chain oil leak so far?

 

No, everything is bone dry so far.

 

@zguy1 --- What's the update on this head gasket repair, +2 years out since your last update?