Head gaskets are fun!

Well, add me to the list of Xterras with bad head gaskets. It's been leaking just a little bit for quite awhile (white smoke for a few minutes at startup after it's been sitting for a while).

I ordered all the stuff today and will be working my way through it over the next several weeks.

Luckily I have several vehicles these days so I can afford to take my time and have the X down for as long as it takes.

I'm not sure how helpful pictures will be since others have already posted pretty good ones (here's one), but I probably will anyway.

it does suck.. good luck with that.

I poured in a bottle of head gasket repair back in ~ 2006...never had to do anything else to it.

Which product did you use?

Still working on this and taking my time - have lots of pics I'll put up eventually.

I'm almost through with the teardown... the driver side head is ready to be unbolted and removed.

The passenger side head is almost ready - I have to figure out how to take the power steering pump and the bracket it's attached to off first.

I gave up on the engine block water drain bolts - they aren't going to budge. Hopefully that's not too big a problem.

A friend who knows more than I do is coming to visit on Friday and we'll actually pull the heads off, check them out (as much as is possible in my garage... is it a mistake to not send them to a machine shop to be checked?), and start putting things back together.

Hopefully the heads aren't warped or anything - they shouldn't be - I am the original owner and I know it's never been overheated and it's only got about 160k miles on it.


I need to read up on that knock sensor relocation thing since I'm in there and I've had that code (P0325 I believe) active for ever. I went to pick up a new knock sensor today but they wanted over $200 for it so I didn't buy it.

Finally put up some pictures... the teardown is complete and the heads are off. They don't appear to be warped and it doesn't look like anything was leaking into/out-of the pistons themselves. I think there was just a leak between an exhaust path and a water path - which would explain the symptoms of white smoke in the exhaust but no milky oil.

Pics are HERE. I mostly took these in case I needed to go back and see how stuff went together and I didn't really pick through them to get just the most interesting ones... here are a few of interest tho:

Heads all cleaned up.

We went ahead and put them on tonight along with the lower intake and torqued everything down per the manual - so I'm well on my way back together. I hope it wasn't stupid to skip the machine shop, but they seemed well within the flatness spec and I didn't want to blow a bunch of money for head work.

hmmm... very very noisy... concerned.

I don't know if the lifters are just dry and a bit of running will fix it up, or what. I've run it twice so far, for a total of probably 4 minutes.

I took a video of the first startup - I took a video of the first startup - HERE. (now on youtube - easier to see)


Any advice/opinions?

Did the lifters go back in the same hole they were removed from ?

I see a lot of pitting on those heads , I would have sent them to the machine shop for resurfacing,but thats just me.

Did you at least replace the valve guide seals ? by the looks of those piston tops I say she was dropping oil too.

The lifters may pump up, go take it for a "spirited" drive for a few miles, that may help.

I didn't remove the lifters - we just backed out the bolts on the bar that holds the rocker arms enough to get those two captive head bolts out and put new ones in.

I just tore it down, replaced the gaskets, and reassembled - no work on the heads because I didn't think they needed any. The valves didn't seem to leak any when we sprayed carb cleaner at the back sides of them

ok, it's good that the lifter position did'nt change.

The test you performed proved that the valves are sealing aginst the seat when the valve is closed , which is a good thing, it means there is no leak down when the valve is closed.

What it did'nt test is the integrity of the valve guide and its seal.

as you know when the engine is shut off oil reacts to gravity and seeks its lowest point, as oil drips down it can run down the exposed portion of the valve stem past the seal and into the cylinder depending on if the valve is open when the engine is off which can cause start up smoking.

I dont know the mileage on your X but if it was at or around 100k I'd have the heads at the machine shop getting the full treatment.If your going to go through that much work it only makes sence to have the cylinder heads professionally checked.

I hope it all works out for you.

woo hoo! It seems to be fine!

I decided to take Master Tech's advice and just go drive it around and within a few seconds of starting this time (which is the 3rd start since the head job) the noise went away!

http://youtu.be/A3Is2woCgJ0

I drove it for several miles and got it up to 60 or so - everything seems fine except that it's idling a bit high... but I haven't adjusted the timing so that might account for that.

Hmm - well now I feel stupid for not getting them done... I didn't know where to take them and didn't want to spend the money so I skipped that part. oh well.

The truck has 149k on it

Good thread. Heads looked good too. What did you use to clean the heads and the block surface? I'm having trouble with all the old graphite material sticking to them.