Elow007

1996 5vz-fe engine, 4WD, manual transmission.

Headgasket was replaced, idle test went fine. When driving down the highway it overheats and never did before.

Had to leave town and friend and family wouldn't start truck for me occasionally. Truck sat for 4 years thinking I was going to have to spend a ton of cash or let it go cheap. Decided to reclaim the vehicle and repair myself.

After the long sit, I thought it wise to replace components thinking it might have been a perfect storm of failure leading to overheat. I replaced the upper/lower radiator hose (oem), radiator (tyc), radiator cap (standt), fan clutch (oem), thermostat twice (Tama, oem), water pump (oreilly's). I also flushed the block/heater core at the radiator hoses/heater hoses as well as the block through the water pump ports.

I'm aware there is a TSB for this vehicle referencing the ease at which headgaskets can be installed upside down or backwards. The truck has 200k miles and I figure why not replace the components, but now it looks as it I will need to install a new headgasket.

Unless I missed something I'm going to go ahead with the HG job. I posted my problem over at Tacoma World and they came to the same conclusion. Well, one guy told me to light it on fire.

I'm willing to do the HG job because I like wrenching on cars, but before I do I would like to see if anyone here can think of anything else before I do this in a week? I really appreciate any input at his point.

Lastly, I do have a weeping freeze plug on the passengers side, I don't think this would cause a total overheat like it has been, but I thought I should mention it.

Thanks again.

Janos01

Hey Elow welcome to the forms.

I have a few questions for you out of curiosity:

1. First off are there any other issues with the truck aside from the HG?

2. what model do you have? 4runner, Tacoma, Tundra?

3. Is this repair for fun or are you keeping this for sometime?

Reason being, for an engine that has 200K+ miles on it, it is recommended that you preform a whole rebuild in addition to the HG as it is a can of worms. Meaning you will be replacing other things in addition to the HG due to the mileage & age of the engine. Also by preforming a HG job the engine is already half way apart so if you have the means, its best to rebuild the whole thing.

If this is too expensive, I would recommend looking for a rebuild or used 5vz-fe.

Elow007

Well that leaking freeze plug is an issue, might as well plan on all of the failing at this point, ball joints and leaf springs need to be replaced and the drivers side cv seal on the front diff is leaking. So it's a bit of a project but I have a daily driver so no big deal.

The truck is a tacoma sr5, and I'll drive it till the wheels come off. I'm down for replacing gaskets, belts hoses etc. I'd let it go before I replaced any internal components like rings, berrings, cams etc.

83

Is that true? That on this engine if you're doing headgaskets, you should rebuild the whole thing? I've done a couple headgaskets on R-series engines with no thought of rebuilding them while I'm there...

I just bought a 3.4 Tacoma with 190,000. I wasn't planning on any major work for the next 100,000 miles or so...

Seriously.

wyoming9

iTrader: (1)

It is just one of those things .

If one has the extra money and your going to do the head gaskets maybe a timing belt.

May as well pull the engine and do the bottom end.

Do you need to absolutely not will it come back to bite you later if you knew that you would already have hit powerball making it a moot point .

Most times people don`t have the option time wise .

Pull the heads clean them up install them buttoned it all up and call it a day.

Elow007

I just want to replace the headgaskets at the moment, perhaps I will have enough courage/time/money to rebuilt in the future.

But back to my original question, can anyone think of any other reason this is overheating after changing the headgaskets? I really want to eliminate all the possibilities before I take it apart down to the block. It just seems like it would be very difficult to not examine the head gasket up against all the ports before you bury it underneath the heads. I'm having a hard time understanding how a mistake like this could be made.

FYI, I wasn't present for the HG job, my friend did it. We called it even after the overheat because we didn't want to make any more mistakes.

TheDurk

You'd think that. However, it's been all of two months since I last heard about someone doing that (swapping left to right):

http://www.toyota-4runner.org/3rd-ge...placement.html

And I have seen at least one a year during the almost ten years I have been on Toyota forums.

Elow007

I read this while lurking, and several other threads with the same symptoms. Engine is fine at idle with heater on, overheats on the road.

So since this is my first headgasket job I'm understandably nervous about getting it right. I have the oem headgaskets and they are labled L and R. I'm viewing images on the net and imaging how they are installed L is the vehicles left side withe printed side down, R being the opposite, again printed side down. The printed side has the seal applied at the factory as well. The image is how I think the headgaskets should be installed printed side down, l on vehicles left r on vehicles right. This image is from the perspective of being in the cab behind the wheel.

Elow007

This image shows the packing seal that's pre-apllied at the factory. Mine is damaged, the top gasket, middle cylinder, upper portion of the image you can see the missing portion of seal. I'm taking them back for a replacement. I just wanted to ask, this printed side with the lettering L and R, and the sealing material is the side that goes down, correct?

Elow007

Just in case some one comes along with a similar issue and views this thread.

Turns out the headgaskets were installed backwards. See the thread titled "1996 unused for 4 years" on tacoma world for pictures of the old head gasket incorrectly installed compared to the correct oem headgasket.

The left and right sides are nearly identical, except for one nickel sized port on the left head that is absent on the right. Mine were installed with the port blocked due to the right head gasket being placed on the left head.

vasinvictor

iTrader: (3)

That was my guess too. Last 3vz I bought from the junkyard had them installed backwards. That's why is was in the junkyard, I suppose.