Head gasket out at 489,000 miles, repair or replace engine??

why not call the shop first and see what they would charge you to do nothing else but replace both head gaskets? doesn't hurt to ask

and changing the head gaskets is an easy job, it just involves taking a lot of stuff off the get to it, the repair itself is simple.

https://www.youtube.com/watch?v=06l5jHMZt0Y

 

Wow, almost 500k on an engine that was supercharged for its entire life...impressive!

 

Ok wow great video,
But now that makes me more afraid that there might be more problems.

The engine never over heated, just started to studded and blow white smoke
And loose fluid.

After watching that video he says that you have to find the cause of the blown
Head gasket, and if you just replace gasket you might end up with blown head again.

Says the block might have a crack, heads might have a crack,
heads might be wrapped caused by over heating, but my engine didn't over heat,

Says there might be other problems that caused it to blow the head gasket.

I had a leak down test done at 450,000 miles and the engine had no issues then.
I think average was around 160 or so.

If I go have one done which I will do this next week for sure I will have some bad
pressure readings I'm guessing. But can a leak down test tell me anything other than a bad head gasket? Truck was running excellent till the white smoke started
and now it shudders and then runs fine off and on.

He mentioned that a bad intake gasket will do the same thing?....
Or maybe I misunderstood that part??
Can a bad intake gasket on this engine let water into the engine on the 3.4 ????

 

there is no reason to do a leak down test, that is to see if you have a problem and that, you already know so don't waste your money.

as to the video, it is assuming the average person will have a low mileage engine that there isn't any reason the head gasket should have failed on it so you need to find out why it happened. in your case the engine is 15 years old with 500k miles on it and head gaskets do get corroded over time so it is not that unusual for a head gasket to fail simply from that on a high mileage old engine like yours.

the video shows you how to do a straight edge test to see if the gasket surfaces are even and THAT is the main test you need to do. if its not even, then and only then will you need to make a decision on whats next. if the head or block needs to be shaved to even the surface then your in the area of a complete rebuild and machine shop work so at that point, and only at that point, you would be better going to a salvage yard low mileage engine.

im sure you will find nothing wrong once you take it apart, after you replace the head gaskets you will come back and post here about how easy it was and your happy you did it. absolute worst case if the head gasket blows again, then you will have only lost a couple of dollars worth of gaskets and your time.

don't sike yourself out of it and get all worried about what ifs, what could happen, what your afraid of running into, just pull it apart, replace your head gaskets and then you will be fine.

 

Ok, thanks for the info,

So then with this motor is there any chance this is related to a intake manifold gasket problem??
Or for sure a head gasket problem??

 

Intake leaks can reveal themselves by observation, after you inspect those gaskets. Not clear on how such a leak would damage a head gasket however, if that's what you're asking. If you want to know if an intake leak would cause your symptoms, my vote is for "highly doubtful."

 

So did you in fact install the blower yourself? Do you have tools for doing stuff like this?

I'm with keaker here, take it apart and inspect. You'll either put new gaskets on and keep driving, or the inspection will prompt a tow to a shop for the machine work unless you take the heads in yourself and/or pull the block and take it in.

But I get the sense here you might be more comfortable finding a shop you trust to do the work. The key word here is trust, and surely there are other places besides the dealer.

If you get a used motor, T100s and Tundras are also possible donors for the 3.4; the latter could also have a 6sp manual too. (How come I don't read about that sort of swap on this site?)

 

I put a 2004 motor in my 1997...just have to change some stuff

 

Ok great advice, yea I'm not really setup for doing this myself,
Wish I was.
I was just thinking maybe I had a bad intake gasket and the
water was getting in from there if possible and not the head gasket.
The oil is not dirty and has no water in it
that I see.
I'm loosening a small amount of water from
the radiator. It blows white smoke on startup for 3 minutes
And then goes away. Yesterday I drove 3 hours highway.
Engine was running great half the time and the other half
it was missing. Check the radiator and was down about
1/2 inch of fluid.
THE SUPERCHARGER was installed by the dealer,
But I have had it rebuilt 2 times anyway,
I found a used 5 speed 3 years ago that had 60,000 miles on it
Just in case mine went out, which it didn't, so I'm good there.

I will call around Denver to see my best price for a head gasket service

My first option would be to find a motor with 75,000 miles on it.
I just missed one last week that was in Dallas on craglist for 1250.00 that was still
in the truck running from a salvage yard.
That would be a slam dunk for me.

 

well just keep in mind that if you get another engine you will have to decide what to do with your super charger and they are worth good money so don't let it go with the old engine, that would be silly of you and you could sell the SC for enough to buy another used engine for.

if you decide you don't need the SC on the new engine I want it so I call first dibs lol, but I doubt you would be happy driving the truck without it.

you may or may not have extra stuff that goes along with the SC such as upgraded injectors and fuel pump or a 7th injector kit with urd or whatever so if its all factory SC and you never added anything added then maybe you don't have all that stuff.

bottom line is you "could" trade in the SC and related stuff to pasy for the replacement engine but at the same time your truck will feel like it lost a lot of power when you drive one without a SC

 

Haha, I'm in Denver and I did not get the 7th injector or fuel pump upgrade.
I did get the small 2.1 pulley that made a huge difference.
Because of the altitude here a mile above sea level, It's not mandatory,
My truck knocks a little if you don't have the rpms up.

Anyway if i decide with a used engine I will let you know.
I'm on the fence for now about what to do and might just park the truck for now.

I'm pretty sure I would swamp the supercharger back on anyway.

I know I won't be happy with out it.

I have to keep the new tacamos and Fj scratching their head at the stop light
and in my rear view mirror. Hehe.

And thanks for all the feedback from everyone

 

well just keep me in mind if you ever decide to sell the SC

as for the engine swap, I cant fault you for just facing the inevitable with that many miles and if you are going to spend money on the engine you may as well do it by dropping in a low mileage replacement and have it installed along with all your SC stuff.

to be honest the price to have that done likely wont be much different then paying someone to replace your head gaskets

 

I'm curious, is it cheaper to replace the whole engine than one head gasket?

 

4bt cummins swap!!

 

3rd Gen 4Runners also have the 3.4 but no 3.4 ever had a 6 speed behind it from the factory.

 

You are hurting the engine when driving like that. There is a leak between water and the cylinder. Probably no more than one cylinder. When you drive taking the water and loosing compression this cylinder runs colder and ECU thinks the engine runs rich, so ECU is leaning the mixture. Gas mileage is great but you will be burning valves way to fast than you should. I had the same symptoms: bubbles in the coolant, smoke on startup, running rough for first few minutes and great gas mileage (25mpg), hardly passed smog because of high NOX. When we removed the head this is what we saw (it is 2.7 engine):




Comparing to other cylinders it was easy to find out which one was to blame for it

 

Over 489,000 miles. Doesn't surprise me it's a supercharged tacoma

Someone said on here that one of their friends had the same truck as me and it blew up (that's what he said) but I don't believe him, shows how long the engine will last even with a blower on top.

 

Keep it numbers matching just like an old muscle car. Do what ya gotta do to fix the original motor if it was me. Awesome truck

 

Here's my 2 cents. I would buy and put a salvage yard engine in it which will get your truck on the road with the minimum amount of downtime. If the salvage engine works out you're done. But keep the original engine in case you are not happy and get it reconditioned without having to get a rush job and then swap it back. Too many potential pitfalls with a 500K engine to assume you can throw new gaskets on it and keep putting 27K miles on it a year no problem.

 

let me add a bit of advice

I think you should just drop the salvage engine in it and drive it like that for a couple of months, then add the SC to it after you are confident everything works fine on the new engine. if you just throw the SC on it right away it adds to the cost of install and then if there is a problem with it running rough or giving engine codes, you don't know for sure if its something related to the SC install or not.

its 2 head gaskets, he has a 3.4 v6 but when I said that, I was referring to just the labor cost to replace then vs labor cost to just drop in a salvage engine swap.

both should talk close to about the same amount of labor hours I would think.