Gamefreakgc

Hey all,

I've got a 3vz-e with poor compression in cylinder #5. All are at 150-160 but #5 is struggling at 115. The mechanic at the shop who used to work at a Toyota dealer said it's most likely a burnt valve. I've been searching the forums here extensively and that seems to be the cause.

I've looked at the FSM for the process and it seems very lengthy. I'm a DIY'er since I'm old-school and like to know how fix everything I own (and to learn what makes it tick, I should have been an engineer). I live in an apartment complex though, so no access to welding, machinery, etc. Just what I can fit in a storage closet and a tool box. My truck is also my DD, so it would have to be a 2-day job tops (Sat-Sun). Is a valve adjustment/replacement out of my league? If not, have people had good results to bringing it to a shop to be fixed or is this more of a stealership job to get it right?

Any experience/advice is much appreciated.

j2the-e

If a valve is burnt, you most likely need a valve job. Adjusting it may help as a temporary solution, but it might not help at all. Adjusting the valves isn't that big of a deal if you have some basic tools and mechanical know-how. Unfortunately, the time to adjust was before the valve burnt.

B-Fake

If you know what you're doing and have all the parts and tools readily available a valve replacement can be done in a weekend. I don't know how involved the process is for the 3VZ, but if it's like any other motor I've worked on once you get all the little stuff out of the way it goes pretty quick from there.

And while you're in there if you're replacing one you may as well replace the rest of them too.

rworegon

The valve adjustment may not be out of your league, however, unless you have a set of shims of the proper thicknesses needed for adjustment you will not likely get it done over a weekend. Why? Because the shims are dealer only and you'll not know what you need until you tear it down and make the necessary measurements. My 0.02...

scope103

If you've burned a valve, what happened to the seat? The seat is tougher than the valve (better heat transfer), but I would expect you need to lightly grind the seat.

You're going to need to remove the head to look at the valve no matter what. If I was going to do it (and I have), I'd just pull the head and drop it off at a machine shop for the "usual" (pressure test, check for flatness, grind the seats and the good valves, replace the bad valves, etc.)

As rworegon points out, you have to be very lucky to adjust the valves in a weekend. The machine shop, on the other hand, has a whole box of shims and can do the adjustment right.

Last but not least, you never know what you're going to find when you get that far into the engine. You might pull the head, drop in one new valve, and slap it back on good to go. Not likely.

Any chance you can get a ride to work for a week?

Gamefreakgc

That would be consistent with every other job I've done: go to fix A and as a result find that B and C in the same system needs repairs as well.

I might be able to get a ride for a day or two, but the daylight is so short (sun sets at 5) I'm not sure that would help. Perhaps I might have to take a couple days off or wait until the days are longer again.

Is this more of a time-consuming or difficult job?

MudHippy

Time-consuming.

Getting ahold the adjustment shims is the only difficult part. The rest is nuts & bolts, taking notes of measurements, and basic math. "Special" tools required are a micrometer, and a set of feeler gauges. Can be easily be done by the beginner mechanic provided with a good set of written instructions(ie the FSM)

yodafan93

ive read about adjusting the valves on a 3vz and it sucks. way harder than any 22re. from what i hear its both time consuming and you need specialty tools. its somewhat difficult. to the point actually where ive heard of alot of mechanics refusing to do it. and if you get a valve job, dont just get one done, youre supposed to do all of them. a valve job isnt that hard but it does take the right tools. youre probably better off taking it to a shop as bad as it sucks to hear. youd either have to spend money to have a shop do it right, with all the proper tools and equipment, and experience on how to use those tools, or youd have to fork out money for tools that youd probably only use once, maybe twice if youre unlucky, and then have to figure out how to use them.

MudHippy

Well...I haven't read about it...so much as HAVING DONE IT MYSELF. And I can tell you that it's not NEARLY as bad as MOST people will tell you(especially some of the dumbasses on this site).

So

yodafan93

lol well if he^ says a 3vz adjustment isnt bad and hes done it, ill take his word for it. Mudhippy, ive seen your posts before and you seem to know what youre talking about. but theres still the whole experience thing and everything i mentioned pertaining to a valve job.

B-Fake

Aaaahh, I didn't know the 3VZ used a shim and bucket setup. Yeah, that could be time consuming. It sounds to me though that the valve (probably exhaust) is burnt out though. A leak down test could tell you for sure. If the cylinder doesn't have good compression because of a valve it's probably not because of the valve lash since the valve not closing all the way probably isn't the issue here. As things wear the lifter/shim will get shorter making for less lift which could have been the initial problem; cam doesn't push valve open as far as it should, hot exhaust gasses are forced out through a smaller area than they should be, and the valve and seat can't handle the extra stress. I had a similar problem in another vehicle with leaky hydraulic lifters. However I don't have a lot of experience with shim and bucket setups so I could be totally wrong, but it makes sense to me .

At any rate if you do need to replace the valve(s) you'll have to shim them properly anyways so it will take some time and patience.

B-Fake

LOL!!! Some people are drama queens, but to be fair, in comparison to the 22r it probably isn't as straightforward. I mean come on, the 22r is about as easy as it gets.

yodafan93

lol true. 22re takes like 20 mins to adjust the valves, and 10 mins is spent just moving the vacuum lines haha.

j2the-e

Valve adjustment is fairly easy. But you don't need a valve adjustment. You need a valve job. If you want to do it in a weekend, find a machine shop that has a set of heads ready to go. I know of one here in phoenix that probably has them and is the best machine shop I've ever used. I'd imagine shipping would be available if you don't have a great machine shop local to you.

scope103

I can't prove this one way or the other, but I believe the most likely cause of a burnt valve is one that doesn't close all the way. The only way that the valve can survive the intense heat of the exhaust stream is by conduction. The valve stem-to-valve guide route doesn't help much, it's the valve face-to-seat that takes the heat away. And if the valve adjustment is too tight (so that it isn't closing tightly) the valve can't get rid of the heat and burns up. (You never hear of intake valves burning.) That's a big reason why valve adjustment is important.

I'm with MudHippy on the difficulty. Re-setting the first one is kinda hard; after that much practice the rest aren't bad at all.

I recommend a tool like this: (lots of people make them). Others claim to do it with just a small screwdriver, but I'd spend the $30 any day.

But as others have said, Gamefreakgc doesn't need a valve adjustment, he needs a valve job. But valve adjustment in the future will keep him out of the machine shop.

Sturmcrow

This doesn't pertain to a valve job only, but I just wanted to point out that those LED head lamps make working on the truck after dark about 1000000 times easier. I have this one, and love it. For me, the best thing about this model is that you can wear it with eyeglasses. A lot of the headlamps have clear housings around the LEDs, so you get a lot of glare off the back of your glasses and can't see crap. This one does not have that problem. Plus, if you pick up 6 rechargeable AAAs (3 to use, 3 to have charging) you can go nonstop, as long as it takes, or until the beer runs out anyway.
http://www.walmart.com/ip/Energizer-...light/15571828

Gamefreakgc

Yeah, upon comparing the two (and considering I have 279k miles) there's no way I can just adjust them and think that'll fix it.

I read through the FSM on how to remove the cylinder heads and I have to say, it's daunting. There are a lot of tools, gaskets, and unique parts I'll have to assemble first. It looks VERY time consuming by the looks of it. I get what you guys mean about bringing it to a machine shop, there's no way I can grind down anything if it had carbon buildup (which I'm pretty sure it will).

Does anyone know of a write-up or video for a 3vz-e engine cylinder head removal and/or valve job? Tried google and got one for a cylinder head gasket, that helped a little bit but didn't show how to remove the rest.

Thanks for the tip Sturmcrow, I will definitely check that out so my wife doesn't have to stand outside holding a flashlight for me lol!

scope103

This site has more "writeups" on how one person removed their cylinder heads than you can shake a stick at. Many of them contain good tidbits (things the manual writer didn't know because he didn't have an old truck!). But you have to know a lot about the job to sift the good tidbits out from the static.

The gold standard is absolutely the manual. If you don't think you can follow the FSM, I wouldn't recommend starting a job this complex.

Just one man's opinion.

Gamefreakgc

I've followed the FSM for every job I've done so far and it's been great. I've just never attempted this large of a project before. I'll troll the forums for some write-up/build-up threads. I'm a visual person, I can read a step-by-step and I'm able to do it but if I see it done then I'll remember it the rest of my life.

Thanks for all the help guys. I think at this point I'll have to save up some vacation days to give myself some extra time but I think I'll give it a go after the holidays. Maybe President's day weekend...

j2the-e

Those heads aren't too difficult to remove. You'll definitely want to spray some wd-40 or pb blaster on the exhaust nuts a day or 2 before. And you might want to do a leak-down test before you get started just to make certain it is in fact the valve that is leaking. Another option is a 3.4 swap. You might spend $1500 or more on the head job along with related parts, gaskets, hoses, fluids. Or you might find a good donor 3.4 truck thats been wrecked for the same price. Factor in another 500 or so for belts, hoses, water pump, exhaust work for the swap and you've got one heck of an upgrade!