Alright I need a little help decision making from someone who knows whats what (95 4runner automatic 4x4 with 177k on it)

So right now I have a leak in my head gasket (Cylinder 6 I think via spark plug test), Somedays I lose a good bit of coolant and other days not much at all, i get white smoke at startup on cold mornings but thats for about a minute or two. oil on dipstick is normal and coolant is normal color but bubbles come when engine is running. So im pretty sure the head gasket or cylinder head has a crack in it.

My dilemma is this either put in a new head gasket (i think I can do this) or swap out the engine for a 3.4L (i dont think i can do this). I would do the head gasket no problem, its like 200$ in parts but ive heard it pretty common for the cylinder head to be cracked and there to be a number of warps requiring machinery (wondering how common this is) so I could get a pair of cylinder heads for 300$ and (maybe) put those in too. Im pretty sure this has been a persistent problem with the car even with the previous owner. I got it from a dealership that got it from the bank (aka repomen), car is in immaculate condition with a quality lift kit so id hate to just throw it to the curb.

I got it in NC but drove it up to Maryland to my gf's house where it is now (stopping every hour to refill coolant to be on the safe side) I work on cell towers by getting flown out 10 days on, 4 days off so id only use the car 8 days a month but would get some good drive time in on it during that.

So the dilemma starts here: Me and my gf plan to travel abroad for 2-3 years starting around May this year, We have jobs lined up and are pretty stoked on it. I ultimately WANT to do the 3.0 to 3.4 conversion but dont want the engine to sit with minimal use (keeping in her parents barn and theyll take it out a few times a month) and get "bad" plus I dont really want to throw another 5k in a car that I wont use for 3 years.

The best thing for me is to just let the car keep chugging along till may then when we get back from travels swap the engine and live my best life. But im worried if i dont fix the head issue itll leave me on the side of the road.

What do you guys think?

btw i found out first about the head issue via the car overheating one day, I immediatley pulled off and let it cool down to put some water in there till i could get coolant but it has been in the hot zone.

 

well if it was me i would just fix the 3vze wait till i burn up the 3vze then swap the 3.4 in. or maybe not even bother with that and just buy another 4runner with a 3.4 already in it. if you are going to fix the 3vze defiantly adjust your valves and get rid of the crossover pipe to prevent your exhaust valves from burning, if you haven't already done so. i think if you could change a head gasket you could do the 3.4 swap if you just watched enough you tube videos and read enough. From what i understand this is one of the easier engine swaps.

 

I may be able to do the swap, id just want a lot more time than im willing to dedicate right now, ie 2-3 weeks. I could probably do the head gasket in a weekend if the heads arent ˟˟˟˟ed. One of the bigger reason i want the 3.4 is the improved mpg so if theres someone whos done it then im wondering what the mpg is after the swap.

the current 3.0 gets 15 or so, i expect to have this car for 150k miles so thats 10k gallons ill have to get. I assumed the swap would up me to 20 which would only be 7500 gallons, saving me about 6k (2.50 a gallon) so itd basically pay for itself.

Right now i am leaning towards the gasket fix im just curious if i try to run it, say another 5k miles if id blow the engine (assuming i stay ontop of keeping coolant in there). Right now it doesn’t mix with the oil but is it common for more cracks to form and therefor mix with the oil with more usage

 

I don't know that I'd count on going from 15 mpg to 20 mpg doing the 3.4 swap, given that you have an automatic. I get about 19 with my 3.0 with a manual, and my son is lucky to break 20 with his manual 3.4 in a 3rd gen, so I don't think there's that much difference in fuel economy. You'll still have the same transmission, so realistically, I'd plan 17 mpg with the 3.4, which changes the math quite a bit.

There are benefits to having the 3.4 in there (power and low-end torque, mostly), but I doubt you'll pay for it with fuel savings.

 

Regardless of 177 K miles I would bet that your heads and block are just fine if it has not been over heated and run hard with a leaking head gasket and the temp gauge pegged in the red. But you probably cannot know that for sure i.e. perhaps why it was sold? The head gaskets on the 3VZ-E have an oblong shape to the combustion ring of steel that is crimped around the edge of the composite gasket material. The # 1 and # 6 cylinders share the same geometry. There are two out-board water galleries that are blind to the head but not the block. They are the shortest distance to the steel crimped ring in the HG. The composite gasket material eventually breaks down and disintegrates were this water gallery into the block can bulge into the opening. The bulge forms from the clamping pressure and it blisters with time. As the HG starts to breakdown the thermal stress cycles finally lead to a path at the crimped ring. This takes a good many miles for this to happen mind you maybe 177 K? As the composite degrades, the crimp ring collapses, then coolant can migrate into the cylinder. With the engine warmed up the coolant temperature and pressure are high. On cool down the pressure in the cooling system can pass some coolant into the cylinder as the heads, gaskets and block cool down. As the head gasket clamping pressure relaxes a transfer of coolant may get into the cylinder . Not enough to hydro lock perhaps but enough to cause some steam out of the exhaust as it all comes up to temperature. When the failing HG is done, combustion pressure and coolant will mix with a plume of steam at the tailpipe. The temp gauge will be maxing out too. But the tell tale is the coolant is disappearing without an external leak.

The good news is #6 doesn't feed the EGR like #1 does. So the EGR won't be putting water into the intake manifold. My 1991 with 235 K let go on # 1. But I let it sit for 4 months before I got into it, oops! # 6 had an insulator come apart so I ended up doing a complete engine rebuild. This cost about $1,400 for parts and machine work with many weekends and after work evenings. Exhaust valves were replaced. The intakes and seats were lapped in the heads. I port matched and cleaned up the runners in the plenum, intake and DT headers. I hand lapped the block after decking to remove the last bit of a dip in between the cylinders. The heads were lapped to a mirror finish. So this becomes more than just a HG replacement if you go with MLS. In my case the heads were flat and not cracked I was lucky and did not have to get them machined. The block was decked & bored, new pistons and rings, crank re-ground and new bearings with conn-rods hung on the pistons < $1000. If you do the HG's and you want to keep the rig for another 100 K I would strongly recommend the MLS and ARP head studs. But to do this you have to lap the block and heads because the MLS will not seal on a machined head or block unless the machine shop really knows what the hell they are doing. Even after mine was decked I had machine shop pull the alignment sleeves from the block so I could fix the dips in the surfaces that were apparent when I placed a straightedge across the block were the cylinders are very close together. I lapped each bank until no daylight could be seen anywhere over the entire surface. I have a total piece of mind now for the effort I put into getting engine sorted.

The 3.4 swap is very tempting as you get better flowing heads and valve gear that make all the difference over what the 3VZ-E has going for it. The 3.4 swap requires an engine with ECU and a conversion kit to get things connected and re-positioning of the battery and air filter. As it is taller either a body lift (yuk) or hood scoop are what I have heard is required to clear the 3.4's intake plenum in the 2nd Gens.

 

I can appreciate the above comment but when you factor in that the OP stated 177K not 117K then the story changes. Mine at 154K had a cracked head ......
Talk to five different people and you'll get five different opinions. I rebuilt my 3.0 and am happy with the outcome. There is one option that you didn't mention ...... sell it to me and I'll take care of it like it was yours. Even send you pictures of it occasionally.

 

I'm at 250k on my 3vze and i've fixed the heads once. Me personally, i'd fix the 3vze so i have a running vehicle and slowly gather parts to do the swap.

 

I am in the same place. Actually, officially, in Sick Bay. Sudden chugging and lots of steam out exhaust so it's critical. I started tear down yesterday hoping just a gasket but you never know.

Question is: Re-Man long block is very dear. What sources could provide an easily usable long block for a 94 4WD Pickup, 3VZ-E?

Any cars?

What 3.4 are you talking about, the GM? I am not getting into lift kits.

 

Hey davidmc36, how are the spark plugs looking for #1 and/or #6?
The 3.4 is the engine from the 3rd Gen 4Runner, so 1996 and later with 12 valve heads, etc.

• The 3.4 this would be a nice alternative to the 3VZ-E.
  • But it is a good bit of sorting to get this swap done.
  • There are companies that sell kits to do this.
  • Your going from OBD1 to OBD2 for the emissions.
• If you go to this thread this is what I did to my 3VZ-E engine rebuild, minus the DIY porting:
  • https://www.4runners.com/threads/new-3vze.9715/ ($2900 but includes DT-Headers)
  • The DT-header is money but helps with getting the heat away from the heads which I think will help with long term reliability.
  • I also port-matched my intake and exhaust and just replaced the exhaust system with a 2.5" CAT back and am averaging 12 MPG around town.
• YotaShop will sell you a turn key engine but that is north of $4K.
• eBay rebuilds are all over the map on price and what you can get for your money. But most seem to be in the $1-2K range.
• JDM might be another option.

 

Cool, thanks for info.

I don't want to be in that deep to update computer etc.

If I stumble on something in the line of a wreck with low mileage, is there any other blocks that fit the 94?

 

I was in the same spot you were in about 3 months ago.. sadly I couldn’t source a 3vze block out from any junkyards or on craigslist, so I ended up machining the block and heads. (ended up sleeving my bad cylinder and boring them all over).

I was on craigslist and found this listing the other day, they are parting out a an engine or selling it whole. If you live near NC it’s not a bad price at all

1st Gen Toyota 4Runner/Pickup Parts
https://wilmington.craigslist.org/pt...062656559.html

 

Id buy a 3rd gen runner and forget abt the 3.0. That is not the engine you want for travelling. If you can fix it for under 500$, do what you can for now but anymore than that, cut your losses and sell it for $1k and wait for someone to lowball you. Use the money to buy a honda civic in the meantime.