Heads gasket issue 2004 3.4 v6

So run down and looking for input from those more knowledgeable than myself. I recently purchased a 2004 Tacoma for my son from a private seller. Two days later son says truck overheating and check engine light on. Have it towed to my mechanic. They say head gasket was put in upside down and misfiring on cylinder three. Guy I bought from has owned it less than a year and less than a thousand miles. Claimed no issues and previous owner had done head gasket.. Having hard time locating a replacement engine so mechanic recommending a rebuild by someone they know and trust them reinstalling. Cost $4-5 grand. Rest of truck is in good shape new frame solid body.

Is it possible previous owner was unaware of issue given the situation?

What is the best option between head gasket replacement/ rebuild engine / replacement of engine.

 

Wondering how they diagnosed a head gasket being installed upside down without accessing it to check and see. Did they actually remove enough parts to verify it was installed upside down? That seems like a lot of labor in diagnosis alone.

 

Part of what I'm looking for. They said they could tell by seeing part of the head gasket exposed? I have used them for minor stuff..my long trusted mechanic works on boats as well but he takes forever/doesn't have a front office/ secretary so communication is impossible. He does great work but hard to pin down. I have been using them for brakes etc so feel I trust them but doing my homework. Is it possible to diagnose that without pulling the head.. mechanic who walked me through it seemed like he knew what he was talking about. Made one mistake with my son's first truck.. trying not to dig ourselves deeper

 

If it's just a head gasket, why does your mechanic want to rebuild the entire engine or replace it?

And yes, the last owner very likely knew there was an issue which is why the low miles and dumping it after a year.

 

They didn't originally push motor replacement hard kind of me / them discussing. My concern is we had the truck less than a week and don't feel I can trust what previous owner did and if damage was done to rest of the engine. This kind of discussion is why I am here to try to make best call I can. My thoughts are for an extra $1500 to take questions out of the engine I'm willing to do that. Not sure if that is smart or stupid. Mechanic did say lower end sounded good.

 

How much is a low mile used 3.4 from a salvage yard? If such a thing exists

 

I can’t recall seeing any exposed edges of my head gaskets. Either side. Now for example on the air intake plenum, you can see the sides of those dual layer gaskets sticking out but that’s way up on top of the engine with nothing removed.

 

So is it possible for a savvy mechanic to spot an upside down head gasket replacement without pulling the head?

 

I really do not know but I’m hoping someone will chime in with a definitive answer. For your sake OP, and now I’m curious.

 

How many miles are on the engine? Has the mechanic done a compression or leak-down test on the cylinders?
A few more details can help us help you.
You mechanic sounds willing to give you options and work with you for a solution which is great. A bit more investigating would be a good investment to better determine the health of the engine before choosing a course of action.
$1500 isn't nothing, but it's a lot cheaper to spend that for a head-gasket job and see how far that gets you before jumping on a whole knew engine.

I'm also inclined to bet that the previous owner full and well knew of an issue but never got around to dealing with it for that year before dumping it on you.

In other news, I've got a spare 3.4 V6 with 225,xxxmiles on it to sell you if you're near Cleveland.

 

No where near Cleveland. 198,000 on motor. New motor option is direction I was leaning giving not totally trusting previous owner at this point. My gut felt him to be a straight up guy didn't seem to be in a position to unload a truck where hiding issues gained him a few grand on the sale but who knows. Trying to make the best move going forward at this point and educate myself. Feel I trust mechanic as well but don't have long history.. somewhat questioning being able to tell if head gasket can be seen to be put in wrong without pulling head in my Guess I'll call local Toyota service see what they say. Appreciate the input

 

Anyone on here no if

1 you can actually put the head gasket on upside down
2 would a mechanic be able to diagnose that without pulling the head?

 

Looking at this image and the bolt holes it may be possible but I still don’t know. You can try calling the number in the upper right of this image and ask them if it’s possible.

 

You can absolutely put the head gasket on wrong and block coolant passages. That sucks to hear that they could have possibly done so when replacing it.

Shoot for fixing the head gasket and you’ll be able to see if anything else was fubar’d.

 

You can put it on backwards on a lot of engines but it does NOT look possible on the 3.4

You would be leaking like a sieve.

Didn't this come up before?

edit: Does look like it's possible to install them on wrong side though as there are two diff. part numbers and only one has a large hole blocked off.

 

Yes you can install and visually see if its flipped. The alignment Tabs in the outside corner (Right side in the image) on the gasket stick out a bit under the head. without knowing how long or how many times the engine has overheated (how much do you trust the seller?) I would tend to agree with the mechanic on the rebuild. Flipped gasket would starve you engine for oil & coolant and thats no bueno

 

So mechanic says engine sounded good otherwise and they are leaning towards replacing gaskets and having heads replaned at $3500 saying rebuild over $5000. Debating the rebuild to hedge my bets but it's honestly over my head Going to try to grill previous owner but don't really know that will get me much. Didn't seem like a guy that would be shady for the difference in a few grand on a vehicle. Mechanic said lower end sounded good and is comfortable it doesn't need full rebuild.

 

How much did you buy the truck for?

If the head gaskets are confirmed to be flipped, who knows if the intake manifold gaskets are installed wrong as well. Both of them have coolant passages and very easy to mess that up if you aren’t paying attention.

It’s all assumptions until someone opens that motor to see what happened.

You can always, very politely, see if the previous owner knew about it and see if he could refund you a portion of the cost to repair it. Worst case he won’t but doesn’t hurt to put it out there.

 

Drain/test the oil, any antifreeze in it is mucho bad for your bearings, if not, don't see any reason to crack open the block if it's not burning oil and the issue is the top end/head gasket.

 

When I did my 3.4 HG I was paranoid about this and read that you cannot put the head gasket upside down on a 3.4 - does not mean its correct though.
There is a section of the HG, I believe its at the front of the head, exhaust side that is visible and this is used to identify the version, 1 or 2 holes. I think you can clearly see it on pass side, driver side is obscured by alt bracket - going by memory.

I believe there are 2 guide pins for the gasket/heads that are asymmetrical and thus gasket cannot be placed backwards.

I looked for pic online but could not find one. I'll get a shot because the diagnosis is troubling to say the least.

Edit - checked mine and unfortunately cannot see the HG once the accessory brackets are on, probably need an inspection camera. In any case if HG is really blown I suppose it does not matter much what the reason is. Unfortunately overheating these engines increases chance of head crack so you might lean more towards engine replace.