MonsterMaxx

It's not reliable and it's not powerful.

ie: if you want a reliable 3VZE, leave it stock,
if you jack around with it trying to get power, not only will you get small returns for your investment, but it makes the motor even more unreliable than it is stock.

SEAIRESCUE

Overheating generally starts when the viscus fan clutch starts it slow death that is usually very difficult to point a finger at until some event occurs that generates excess amounts of heat the fan can no longer remove. Through the process of elimination this is my proof that the GD fan clutch is not reliable with age. Your situation of pulling a trailer is a classic precursor to gasket failure.

Throw that fan in the trash and replace it with a flex fan. Have the heads checked for flatness and lap the valves with new stem seals. It will be your last head gasket job.

What cha waiting for?

olharleyman

If your not in a rush to do your headgasket I will be doing my 3.4 swap soon and will make you a sweet deal on my motorwhen I pull it. If you are doing the rebuild soon let me know where you are and I will come give you a hand plus my buddie is a toymaster mechinic for any info you may need or want.
just sayin

runethechamp

I think this is a HUGE misconception. That fan is almost NEVER on. In the 8 years I've had my 4runner, that fan has been on less than 10 times, except for when I start the car of course. This might be different in warmer places than the Bay Area though.

TNRabbit

The overheating started with a small water pump leak and the engine didn't even show any signs until it had blown all the water out of the engine. That problem has been fixed. The larger problem is why does it continue to blow head gaskets (2) when it all specs out great?? Before you answer with a premature "head bolt torqueing procedure" or other common problem, read both my threads on this entire ordeal. I was EXTREMELY meticulous with the entire process. Also, for those of you who say the 3VZE is unreliable, I think they are EXTREMELY reliable until you have a HG problem then it seems to be almost impossible to stop from that point forward. Perhaps it's because there are a LOT of DIYers on here who don't quite do the job right....I dunno. All I know is I was very happy with the engine for the first 200,000+ miles....

Lysmachia

This has to have been one of the most frustrating things to go through. I really feel bad for everything that happened. Me - we dicided to go with the 3.4 when the headgasket blew after 18K on the 2nd rebuild. However I am putting a lot of pressure on a 3.0 running 5.79's and 35's at highways speeds at times...

But again I am not saying 3.4 for you - especially since you did do all the research and worked so hard to get this right. I guess the luck of the draw is that once a 3.0 had a HG issue it's so hard to turn it back :mad:

MonsterMaxx

Rabbit, what 'improvements' did you do to the motor when you 'rebuilt'?

runethechamp

I have no idea why your headgasket has gone twice in this uncommon location, but I have a couple of general headgasket ideas I can throw out there.

1. I would definitely go with an OEM gasket. I don't know enough about how other gaskets are made to say they are inferior, but why try to save $30 or $40 when you are already that deep into the engine.

2. I started thinking about the bolt/stud discussion. Even though the threads are lubricated with oil I can see that the spinning resistance from the bolts will be a lot higher than the resistance from the nut on the stud. The bolt will catch a lot more threads than the nut and you also have a possible factor of steel on aluminum contact versus steel on steel contact. If the normal Toyota tightening procedure is followed I can see the nuts providing more (and possibly too much) clamping force on the heads.

Again, don't know if this means something, but it's at least worth a thought...

thook

You're right about the difference in clamping force.....HB's vs. studs. I'd asked a friend/mechanic who's been building drag and street engines for many years about it recently because I'd considered using studs on my 22re rebuild. He favors studs over HB's for a couple of reasons, though I don't recall what he said offhand. I only remember he said the clamping force would be greater and more even, but would require less torque. In which case, one would need to follow the stud manufacturers torquing recommendations. I'll have to ask him about that, again.

Incidentally, I chose the reuse my original HB's. He'd also said that the 22re just doesn't see enough compression to warrant using them.....cost vs. practicality (or something to that affect..)....in a normal application provided the HB's are simply installed properly.

TNRabbit

It was a standard rebuild with quality parts (mostly OEM), but an entire engnbldr rebuild kit as well.

MonsterMaxx

so, no headers, cams, oversize valves or any of the other 'hop ups' on your rig?

TNRabbit

nope.

MonsterMaxx

did you machine the block and head faces? how much did they take off?

TNRabbit

I did not; spec'd 'em out with a straightedge & they were fantastic. Less than 1/15th of max allowable warpage from the FSM, and that was the BLOCK. The heads were dead straight.

MonsterMaxx

I believe you've found the problem. It's more than just flatness, it's smoothness too. Those heads move around like crazy which is part of the whole headgasket problem to begin with.

abecedarian

I'm a tad new here so I missed your whole thread about the build. Sorry it went south on you.
Since it's the same cylinder both times, maybe you've got a slight variation in the piston crowns / deck height causing a tad bit higher compression ratio and a predisposition to detonation or possibly a weak injector.
If you fix it, O-ring it.

dieselloco427

OEM head gaskets!!!! I have 125k on my stock "redesigned" HG's from the dealership. (The original owner had the engine rebuilt @ 94K miles with the HG recall). I'm going to replace them again this summer, not to take any chances ruining the engine. Considering the problems that the 3.0 has, I did not even think of putting aftermarkets into the thing.

TNRabbit

Ancient thread resurrection:

I haven't been around in ages, but I think I finally figured out what was causing this. I'm running @ 210 psi compression (Stock is 173) and the fuel system was never adjusted to compensate. I think for whatever reason there's a slight difference in valve adjustment or compression for that cylinder (1) and it' probably running a little lean so I believe that's what has been causing me to blow out the head gasket on that cylinder. I've been going over and over it in my mind with the truck sitting in the driveway now for OVER A YEAR...

Whiplash Willy

A clogged CAT or crushed exhaust pipe can blow a head gasket. Check out the bulletin "Those Mysterious Hot Spots" on this website:

http://www.oregonengines.net/bulletins.nxg

TNRabbit

This has been mentioned several times but is not the culprit.