bad head gasket, fix or motor swap, want to keep manual trans
 

So, I have a 1999 4wd manual transmission right now and I really love it. I just lifted it this past summer and have taken it wheeling a few times and really want to keep this for the long haul. The PO took care of timing belt/water pump/etc. However, I've had seeping valve cover gaskets as long as I've owned it, which is about 10K miles now. I'm not sure of the exact milage as the cluster was swapped at some point but it reads 160K now.

Sadly, confirmed that there is fluid in the #4 cylinder every morning after sitting overnight so head gasket is needing replacement. My question is around whether it would be worth the replacement or try for a swap, with the requirement that I really really want to keep my manual transmission so I'm not leaning towards a v8 swap although I did read there are some adapters available like this one

I was thinking instead to buy a later year (lower milage) wrecked manual trans taco or FJ cruiser and take the motor/trans/t-case from there and swap it in to mine. It would certainly be easier to stick to a 3.4L 5vz based engine which came in tacos up to 2004 but what about the later 4.0L V6s with manual trans like the the FJs and tacos? Has anyone done something like that? How hard is it to splice up the wiring harness or is there a company like xat racing that can make a harness? Obviously, engine and transmission mounts would have to be fabricated, new driveshafts made, etc.

Does anyone have experience with this or am I creating more problems for myself? Curious what the crowd thinks would be the best option here. I've read a bunch of threads but definitely admit that I could search and read more still. Probably the cheapest option is to find a 3rd gen 4runner and swap the engine and keep everything else but if there's a good alternative, I'm definitely willing to explore that.

Thanks in advance

Looks like you're fairly new here, so check these out:

@Joelzy 's Joelzy's 96 5SPD(daily) & 5VZ block-up rebuild

@Fadiddy 's Fadiddy's 5VZFE Build

I've considered what I would do in your situation, though I've got a auto transmission. I would buy a JDM engine and slowly take my time to fully rebuild it and at the same time swap in a manual transmission. Not sure if you've got the time or are looking to get it on the road ASAP, but IMHO that's what I would do.

Thanks, I'll read through those, I admit I haven't read too much of the build threads, but I have been lurking for over a year and trying to learn what I can.

Why JDM vs. buying a wrecked 4runner or taco and rebuilding that engine?

https://media.giphy.com/media/SXjSd9UIL6dJC/giphy.gif

Based on my experience, if you're thinking you'll just replace the head gasket(which would be easy), thats usually not quite enough. i dont know the numbers but i think most of the time these heads will need milling/decking after blowing a gasket(if they are good enough for that, some just cant be reused due to warping or cracking). My block even needed a little milling with a 140k mile HG blow out.

If thats something you're up for, i actually really enjoyed the full rebuild and am very glad i did it. a lot of mishaps and steps backward but all in all i learned a ton. Just make sure to use OE parts which can add up quickly.
A lot of people prefer the JDM swap route to ensure a factory sealed motor not to mention its sooooo much easier.
havent really looked into alternative swaps, i dont think another V6 is really worth the trouble but i've seen a few V8 and diesel swaps which seem to make a 5VZ rebuild look like a walk in the park.

This guy knows ^^^

Why, not a 2JZ swap?

https://i.imgur.com/WVifqHq.jpg

I find your statement interesting. I know the heads can sometimes crack and need to be replaced but you make it sound like if a head gasket goes, you should be ready to get the heads resurfaced and possibly pull the whole engine out to even do some resurfacing of the block. Is this something unique to this engine. I owned a Subaru that had a blown head gasket, pretty common with those engines, and it was just a case of replacing the gasket.

What tools did you use to determine the block and heads needed resurfacing. I saw one video where a guy just used a straight edge to see if the block surfaces were true so I'm curious if you used the same technique or something different.

Unless you have a wizard inside your engine, you could and most certainly can get away without milling. The most common cause of a warped head is due to overheating, if you caught the failure early enough and never had problems with over heating, its probably 98% chance your good.

Your best bet is to skip the decking and just find a set of good heads that never overheated. Getting your heads decked by a machine shop is one thing, getting a set of used heads off an engine that never over heated is another.
@mtbtim , you use a straight edge and feeler gauges.

@rexassian In my situation I have the time and space and the knowledge (or rather balls) to do it myself. I also have other vehicles so I wouldn't be stuck without the 4runner.

I know this is quite a distance away from you but you could pick up an engine such as the one we have locally here in the PNW (Heck, fly out here and trailer it back) and in this case you'd have some extra parts

1998 toyota. 4runner engine and transmition for Sale in Tacoma, WA - OfferUp

I might actually consider picking this up just to have the engine to rebuild if/when my engine goes. ☺

i think it depends if the powerplant got hot enough to warp the block/head. if you catch it early enough im sure you can get away with it, although if it were me and i managed to not overheat it, i would still check for flat-ness. everything is already apart and out. what is one more small thing to do? hell, if you dont do it and the mating surfaces are not flat you will end up doing it over and over until you get them flat.

was your subaru an open deck head? if so, they seem go to through headgaskets fairly quickly. how do i know? i have an 02 WRX apart in our shop right now.

i have seen a lot of folks use a feeler gauge and a straight edge. you should be able to do the heads off the car no issue and the block in the car without issue.

4.0 is a waste of time. Better off going V8 if you want all that work. The 6-speed they came with is a shitbox too.

That sounds like where I'm leaning. I have another car and have the space to work on my 4runner, but time will be at a premium. I'm in central texas and there seem to be some crashed cars popping up from time to time around here. I might end up just grabbing a lower milage one, cleaning up the engine, replace timing belt/water pump/tensioner/plugs/wires, and swapping the engine over. Then I have my old one in case I need to do a full rebuild. That seems like the fastest route, last thing I want is for the 4runner to sit for a year while I tear it down and rebuild the engine. Am I crazy to think I could do an engine swap in a weekend with help and the right tools? I would pay a shop to do the head gasket work but it looks to be around $4-$6K depending on what else they find, which I have a hard time shelling out just because I'm cheap at heart and would rather do it myself if I can.

Anyway, I realize I rambled a bit there, hopefully I can figure something out and I'll start a build thread to document.

Can you please elaborate here? Why is the 6-speed a shitbox?

when i say "based on my experience", i mean just that. I'm fairly new to these but it seems like more often than not the examples of bad gaskets equal more than just swapping it out. I definitely came into it thinking i could just swap the gaskets but quickly fell into a much deeper pit.

I straight edged mine once torn down and it was barely noticeable but the cylinder ring on the gasket had blown into the cylinder.(I bought the truck after this had happened so i have zero knowledge of what it went through when this happened but the kid was an idiot and i imagine he overheated it.) wasnt a giant concern as the machine shop was going to do a valve job regardless and would check them before proceeding.

I had planned on the machine shop just dipping everything, honing the cylinders(turned into boring) and doing 2 valve jobs but they quickly informed me that the heads wouldnt be true as is.
i could:
1. deck these heads and block or
2. deck the block and clean up the sludge filled JDM swap heads. They thought the original heads were the right bet after seeing the amount of sludge in the other heads.
(they also noted that they were very used to decking 5VZ heads with all of the early HG failures)

Now i think early detection is probably a different story and i very well may be a minority :behindsofa:

not crazy, definitely doable just plan for hiccups and parts runs

If you have to ask this then I'd say "yes" you're bat-$hit crazy ☺

I sure as hell couldn't do it! I'd have to tell me wife that we're not going to be use Cliff (we named it) for a few months ☺

bingo!

https://www.iaai.com/VehicleDetails?...oadRecent=true

this looks like a good motor swap candidate.