UPDATE to blown head gasket. i need some advice and answers.

i posted last weekend noting that i was about to dive into my rig and this weekend i did. everything went smoothly and i got the head cylinder off successfully with no obvious cracks in the head cylinder.

after inspecting the head gasket it failed on all four cylinders torn all the way around. i will include pictures, but this is where i am really in need of some advice.

cylinders 1-3 are heavily coated in carbon build up and residue. pitch black flakes.


theoretically in my head i believe that i should be able to thoroughly clean the pistons with carb cleaner and fine clean with acetone and continue on with the rebuild.

new gaskets are ordered and on the way but i havent orderer the remainder of the parts just in case worst case i gotta dump the engine and swap something else in.

i also had questions about my cam shaft gears. looks like theyre torn up pretty bad. get new cams?

the whole engine was majorily out of alignment which likely put all this into motion.

 

Looks to me like only one cylinder failed - the clean rusty one. The rest look normal to me

As far as clean up goes, plug all the holes you can and start scraping. Try not to scratch the block too bad. Don’t use abrasives or anything that can come apart and leave grit in your engine.


What makes you think the cam gears are bad?


What is an engine out of alignment?

 

thats good news! i only started the engine once when all this happened so it hasnt ran for more than 3 mins in the course of a month and half. i plan to start cleaning everything tomorrow.

it was simply a speculation about the cam gears as i saw what i thought was grinding. im not 100% sure about that.

when i started roatating the timing chain the engine wasnt in line on dead center before i started working on it. maybe the valves werent aligned properly because i have heard small tickings for the last 4-5 months i would say.

 

How many miles on that block......
it looks the oil ring has failed......which is the first one to go.

lot of toyota and lexus owners abuse them when they're newish.

I notice the head looks way cleaner than the block.......wonder if its on its third head gasket.....or even replaced.



...
yeah went and looked at first thread.....330K is alot to gamble on...

It would of been nice to do a compression test before pulling it all apart.

It would of given you a better feel for your whole situation...

Thats something we should recommend here from now on...
wet/dry compression test before you pop the top.

so that you look at all the pieces in play...



Here's what it should look like



maybe head and shoulders shampoo once a week to control the flakes...

 

I notice that lot of these the egr plugs up past the 160K....
and that was put in place to keep from high heat building in the exhaust manifold...
thats a big reason these 4-banger's gasket fail....right there on that side...
doesnt take a genius to see that....seen it again and again...usually about at 200K+

If you get rid of the egr......you got to get rid of the cat too.....thats whats causing the problems.......they double cat the later 2rz's to spread that heat...
The pipe between header and cat acts as a waveguide to the infra-red radiation.
Sounds crazy but long wave radiation acts different from short.....has long reach, big punch...

That heat wont show up on your temp gauge....that sensor is in a constant flow water jacket....if it did, you wouldn't have so many gasket failures...duh....
The aluminum head with the iron block under it is not gonna like that extreme localized heat....


Just be happy you dont have a prius...getting to and replacing that egr is about a $4000 job....



got to admit 1st/gens here are getting about 3 blown HG's a week....
so you got helper burn out here.

about half the time you guys dont take the advice.......already got your minds made up...

 

I would suggest a new engine. Something with six cylinders. Or have a machine shop go through the one you have.

 

I'd be careful replacing too many things while you're in there. In my opinion, if the HG blew, just replace it and put it back together.

I had a head crack on my 5VZ, and thought while I was in there I might as well replace X Y and Z.
At the end of the day, with it all added up I spent more than a used engine would've been, and almost as much as a rebuilt one.
Take a hard look at every single part, gasket, bolt, connector, cleaner, etc etc you will need to buy and see if it'll be worth it. Even brake cleaner became a significant line item for my top end rebuild at the end of it all.
I was at 290k, and while my top end is now brand new, the bottom end is still a 290k block. Could've thrown in a 100k motor instead..
Something to think about.

 

I did a head refresh at 220k. Bottom end is basically perfect and burns no oil so it was a no brainer.

On second look at this one I am definitely curious about the concerns about oil consumption raised by Osilver, it definitely does look a bit oilier than what I remember - could that be a hg thing or a piston thing?

 

Yeah if you been driving it for years, you should know what u got...

IF it wasnt burning oil and everything looked good on disassembly...

That car nut guy has taken these apart at 300K+ and they almost looked new in the cams,chains,sprockets...ect

but the lexus that were neglected....some didnt make it to 200K

Some make that initial investment on a new car.......and then let it rot...



A lot here have had these a long time.....most of the new comers have not.

Well maintained one should last way past 400 or 500K....
thats what you get with under powered engine block design pre 1959...

they just modified an existing marine design with off the shelf automotive parts.

when they tried to deviate from that design.....dreaded 3vz......it didnt really work out good for them...


My cousin bought a new cutlass back in mid 70's
it made it to 67K with no oil changes....just topping...
before it blew up.....

 

yea i was pretty shocked at the condition of the head cylinder whenever i pulled it off. it definetly got touched by the previous owner, but that information is unknown to me.

i 110% agree, compression test was required but it had completely skipped my mind between this eig being down and doing a full throttle body rebuild on our van along with other maintenance and real life issuses going on.

i can confirm that oil consumption has never been an issue ever since i put a new valve cover gasket in during november. i changed the oil then and havent lost more than quarter quart.

i agree with @time623 and simply doing gaskets, water pump and fuel injectors. that should be as far as i go with it until its started up. im trying to contact machine shops today to get the head cylinder looked at and ill shop around to see what i could find a motor if i can score a good deal

 

Look at the honing in the cylinders.....still see cross hatching...

see any shiny or wear paths in the walls?

clean em up and look real good......post anything questionable





And he's damn straight right......you can really get into a lot of money...

dont make rash decisions.

 

I wanted and got a whole new engine and everything that touched it....

Now the deal is.......they'll have to bury me in it....



After studying for years.....buying the block and head separate seemed to have greatest chance of long lasting success....

Buying them assembled together is always cheaper....but much more risky.

Almost all the nightmare stories I've heard.....they were bought together.
and then something went wrong.....usually in the head.

 

This would be an excellent time to swap out the motor mounts.

it will never be easier.....

Unfortunately since covid.....the oem ones have doubled in price...

 

look on 1st Gen Market place
there is cheap 5RZ motor f/s....saw thread last nite

 

By the time you buy the radiator, ecm, engine harness, sub harnesses, cables,
and move everything to new mounts/perches

it would be way easier and cheaper to just go buy one with 5vz already in.....you know a 4month shortcut...


you got to realize these new or used parts are unbelievably expensive.......taco war vet here.....

have you priced an IAC lately, or even one of those $200 fuel hoses......and it takes two...


wait till you see what the oem motor mounts go for now......wow
LCE used to have em for around $100.......used to.....

 

But dont tar em yet...

about 6mo ago someone had a brandnew 2rz shortblock still shrink wrapped on the pallet on facebook market for my greater metro...

So they can be had.........trouble is most people are in a hurry... and dont have time to dick around with stuff...


The heads are fairly easy to get.....the blocks, 3rz and 5vz are in short supply...
and usually from quality sources, there is a wait list....

 

@O'Silver_Taco theres been a gnarly set of storms rolling through recently so i will continue cleaning when it dries out, but youll be the first to know with what i find.

good mention on the motor mounts, something ill try to wrangle up if possible.

this whole project has the risk of being a money pit, but the goal is to get it back on the road consistently and conclusively make up my mind from there.

its going to the shop as soon as its done, which locally is a 5 minute drive from where i live for full tests.

ive wanted to swap engines for a long time,but aint made of money and times are hard enough as they are so thats not in the future.

 

https://www.tacomaworld.com/threads/fs-joshua-tree-ca-5vz-fe-motor.829916/

 

Unless you can go and see and touch the actual truck it came out of.....
I wouldnt trust anything that someone says.....

the JDM engines are hit and miss.......with about a %60 success rate....

with the 5vz JDMs being the least successful..

 

I may not be the best to consort........I chose the high road because I didnt ever want to go back.

To put it in by someone else ...between 6 and 7K total....

but now its got 20K on it.....I'm 63 and put about 5K on each year....
so you do the math....

when/if one of those many parts break......I dont panic......instead, I'm pissed...