Rebuild a 3.4l Engine

[YotaFun]

Why in the world would I go an do such a thing?
Isn't the 3.4l bullet proof???

Ever since my frame swap I have noticed my truck has not really been up to par in the power range.
Yes it is tired at 215k of hard miles (well at least 155k of those from me) but still something is def not right in mine.
I noticed that even with the newer transmission (the one in the donor truck had been rebuilt and pulled really well with the engine from that truck that had 270k on it) my truck lacks power.
I have also noticed a higher rpm misfire, well I wouldn't say higher, but lets say I have it pinned to the floor for a hard pull to get up to speed to merge into traffic (cause on the east coast people go fast in the slow lane and slow in the fast lane) the truck misses, I can def feel it.

So this thread is going to be a place holder and planning thread for a engine rebuild.
I still have the engine from my donor truck, and yes while the mileage was high, it ran better then my truck, the only reason I didn't keep it in my truck is because it leaked oil like a sieve and the valve stem seals leaked a bit.

The plan is to tear down the engine to the block, and inspect it.
If the cylinder walls and pistons look bad, I will break the engine all the way down to the cranks, get the blocked checked and then go from there, this being the worse case scenario.

If the cylinder walls and pistons are good, the plan is this, reseal the engine, with all new gaskets, new valve stem seals, new knock sensors and knock sensor wires, new timing belts, water pump, idlers and tensioner, send the injectors out to witch hunter to get refurbished and then pop it in and plugs and wires.

So I am open to suggestions on what I should go with as far as gasket kits and what not, I have a few ideas in my head right now but I would like to see what everyone else has in mind.

I will def be taking a lot of pictures for everyone and try to remember to include torque specs and such.

[Seanz0rz]

Sounds like a great plan to me. Not sure what your budget is, but I'd toss some forced induction on top of it.

I am very interested in this, I know I will end up doing mine sometime in the future, probably 2 years out or so.

I would do a compression/leak down test before you break it down, this way you can see how well the pistons rings are doing (and the heads for that matter).

You may want to try to collect a couple more injectors to send to witchhunter, this way they can pick the 6 that match the best.

Gaskets, I'd stick with Toyota OEM.

[DHC6twinotter]

I used the link below for my my timing belt kit. Supposedly, it's all OEM. That was nearly 40k ago, and so far so good.

http://www.ebay.com/itm/Toyota-3-4L-V6-Complete-Timing-Belt-Water-Pump-Kit/190521450224?_trksid=p3984.m2049&_trkparms=aid%3D333005%26algo%3DRIC.FIT%26ao%3D2%2 6asc%3D357%26meid%3D4888122077300832622%26pid%3D10 0023%26prg%3D1187%26rk%3D1%26rkt%3D2%26sd%3D190521 450224%26

[paddlenbike]

If you just want to tear into an engine, go for it. But at 215k miles, there shouldn't be enough wear to warrant tearing it down. Check the compression, check the valve lash, have the injectors cleaned, do the full maintenance sweep--plugs/wires, throttle body, iac/maf cleaning, etc. Then see where that leaves you, particularly if budget is an issue. Just my .02.

[YotaFun]

Sounds like a great plan to me. Not sure what your budget is, but I'd toss some forced induction on top of it.

I am very interested in this, I know I will end up doing mine sometime in the future, probably 2 years out or so.

I would do a compression/leak down test before you break it down, this way you can see how well the pistons rings are doing (and the heads for that matter).

You may want to try to collect a couple more injectors to send to witchhunter, this way they can pick the 6 that match the best.

Gaskets, I'd stick with Toyota OEM.

The budget is as money rolls in -_- lol
I am back and forth on the forced induction, I am thinking I want to do the york compressor more then the S/C especially if I will be eventually regearing to 4.88s.

I did a compression test on it and all was well I need to get a leak down test done.

I will have to see what I can dig up for more injectors.
I was also throwing around the idea of throwing new injectors from the 4cyl in, I remember Mastacox did that I believe with his S/C instead of the bosch plugs.

I am going to e-mail my old parts guys and see how much the kit is again, iirc it was like $300 without valve stem seals.
I would like to go OEM though.

[YotaFun]

I used the link below for my my timing belt kit. Supposedly, it's all OEM. That was nearly 40k ago, and so far so good.

http://www.ebay.com/itm/Toyota-3-4L-V6-Complete-Timing-Belt-Water-Pump-Kit/190521450224?_trksid=p3984.m2049&_trkparms=aid%3D333005%26algo%3DRIC.FIT%26ao%3D2%2 6asc%3D357%26meid%3D4888122077300832622%26pid%3D10 0023%26prg%3D1187%26rk%3D1%26rkt%3D2%26sd%3D190521 450224%26

I got that same kit for Stepdads 4Runner as well as mine, was still cheaper then my price at the dealer.

[YotaFun]

Little update since this post,
As Ken suggested I did a full maintenance sweep of the 4Runner, minus plugs and wires (did that before I left Toyota in October)
and I also switched 4Runners with a buddy of mine to compare our findings, and came up with some interesting conclusions.

First, I found a generous amount of oil in the intake, I changed out the PCV valve and I hope this helps out that problem, cleaned the IAC and TB and MAF, ran seafoam through the intake and the fuel system, all seams fine but it still has what appears to be a miss of some sort, or maybe not even a miss which brings me to:

Second thing, my friend and I both agree our engines are running well, but there is a new issue, what we thought was a misfire is not, but at the same time we can't quite describe what it is, I will start a new thread to explain in a bit.

Third, a few of my vacuum lines have been popping off on there own, and are looking tired, so I will be ordering some lines and replace as much as I can, while only ordering some of the special sizes from Toyota.

So for now, this is kind of a just fun thing to do for myself, just have the engine around incase either mine or my stepfathers decides to finally go.

I unfortunately haven't had the time to email my old parts guys, but I am somewhat leaning towards on of the kits off of rockauto for the engine reseal, I just vaguely remember the OEM parts being a ridiculous amount of money...

[Seanz0rz]

I would swap out plugs, wires, and coil packs to a known good set, and see if that solves your near miss. If it does, swap back in old parts until it comes back, one coil pack at at time, one wire at a time. In my experience, the engine is really picky about having extremely good spark.