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Discussion Starter · #1 ·
Last Friday I was coming home on a nice curvy road having a good time. On the last turn just before my house I was in 3rd around 8000 rpm. I had to break a little to make the turn and I wanted one last good red line shift through 4th. Well I guess I hadn't slowed down as much as I thought and throwing it into 2nd caused some odd noise and loose of most power. :eek:

I pulled over and let it idle and it's the worst ticking I've heard and I own a 91 3000gt vr-4. I knew that I had shifted way too early and over rev'ed the motor smacking the valves on the pistons. :sad: Live and learn ... it's entirely my own fault. I've driven manuals my entire life and never done something like this. They say that most accidents happen a few miles from your house. You get lazy and complacent ... and that allows you to make mistakes.

Well I just got the head off (with out pulling the motor) and I see that every intake valve has a nice shiny side to them and not exactly fitting the head very well. I would say I have 20 hours into this project so far. Examining the pistons and piston walls ... I don't see any problems. Each cylinder walls are clean with no scratches so I don't think I did any other damage.

I received a full new set of valves, springs, retainers and sleeves from MWR. I should be able to get the head to our local machine shop that does nothing but heads early next week.

I'll snap some pictures and post updates when they happen. I just figured I would share.

Good night!
 

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Sorry to hear about your experience. It sounds like you may have gotten off easy. I'm no expert, but if you shifted into 2nd at around 95mph, and the clutch fully engaged, your engine rpm was probably around 11,000. In addition to valve float, you risk damaging your pressure plate and oil pump. I wonder if a spun bearing could also result.

Not trying to be Mr. Doom and Gloom, just happy for you that you only dinged the valves. You sound like you have substantial mechanical ability so you'll also save quite a bit on the repairs.

Keep us posted on the valve job, and I'll keep my fingers crossed that nothing else is damaged.
 

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Discussion Starter · #3 ·
carlover, I'm not sure what the RPM's were but I pushed in the clutch as soon as I realized this wasn't going to work. I'm going to do a good run through of then entire bottom end to make sure nothing else is wrong. I knew that I busted the valves so I wanted to get the head work done as soon as I could. some times it could take a little for a machine shop to find time to work on your stuff.

I've rebuilt a number of motors and trannys in my limited mechanical experience. I love working on machines and understand them rather well. I also have a sickness of buying every tool that I find and that I don't own. Having the right tools for the job makes it much easier. I also don't trust most mechanics (reusing head gaskets and what not) so it saves a good deal of money and also gives me a piece of mind.

Thanks for the support!
 

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Discussion Starter · #4 ·
O ... and I had planed on doing a light weight flywheel, new clutch, AC delete and maybe light weigh pulleys this winter any way. So this isn't all that bad ... just more money.
 

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The title of this thread alone is enough to send shivers up anyone's spine. :eek:

That being said, sounds like the damage could have been MUCH worse and you're lucky to have the expertise to do any necessary repairs on your own.


.
 

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Discussion Starter · #6 ·
after taking off the oil pan ... this is what I found. Any ideas as to what it's from? It doesn't ring any bells for me.

snapshot.jpg


So ... I've broken more than I thought. Now I'm wondering if I should just buy the full block from MWR for ~1600$ and call it a day. Then in the future I could build my current block with some nice parts for more power.
 

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Looks like a valve guide.....NOTE: there is no rev limiter protection on a downshift. ( and you shouldn't depend on it for upshifts either )
 

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Many a 2ZZGE that were in Celica's, has met it's end this way. My neighbor's son's car being one of them . I hope you are more fortunate, but supect the damage will be greater than a few bent valves and dented pistons.
 

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Last Friday I was coming home on a nice curvy road having a good time. On the last turn just before my house I was in 3rd around 8000 rpm.
Your neighbors must love you!
 

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thanks for the info, we all appreciate it.
please keep us filled in on what all you do find.
anyone could do the same thing.
sam
 

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So ... I've broken more than I thought. Now I'm wondering if I should just buy the full block from MWR for ~1600$ and call it a day. Then in the future I could build my current block with some nice parts for more power.
Get the short block and the upgraded head from Monkey. Heavy duty valves and springs for 1200.00 with core exchange. You will have all new parts, no worries.

You can buy a brand new stock head for $600.00 from
https://www.1sttoyotaparts.com/partscat.html

They sell short blocks too for 1350.00


Just a weekend job to R and R the engine. Then your back on the road.
 

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Discussion Starter · #13 ·
Your neighbors must love you!
I'm the only young single guy for some distance. They absolutely love me! rotfl




Get the short block and the upgraded head from Monkey. Heavy duty valves and springs for 1200.00 with core exchange. You will have all new parts, no worries.

You can buy a brand new stock head for $600.00 from
https://www.1sttoyotaparts.com/partscat.html

They sell short blocks too for 1350.00


Just a weekend job to R and R the engine. Then your back on the road.
That is awesome info Jim! I'm checking that sight out now. Thanks
 

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Discussion Starter · #14 ·
just a quick update:

If you look at these two pictures you'll see that my oil pump is trashed!!!! You'll also see the 3 mystery bits that I couldn't place earlier. They are where the bottom screws to the top.

snapshot-2.jpg
snapshot-4.jpg


Pistons, rods, crank, all else block looks good after inspection. I've not taken a micrometer etc. to them all yet but they are not in little bits like this. :D

I also have micro-cracks on the valve guides of the valves that hit the pistons. I'm going to have them all replaced in any event ... doing valves might as well have the guides replaced.
 

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holy sh*t!
 

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Discussion Starter · #17 ·
WoW ... some of those look much worse than mine did. I couldn't initially tell it was broken until I took it off and a piece fell out.
 

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Recommend inspecting the harmonic balancer too. I've seen at least two reports of them cracking during a zing like yours.
 

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Discussion Starter · #19 ·
Thanks for the heads up xtn. I'll have the rest of the block torn down tonight. I'll see the true extent after that.
 

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I suspect the guy in the Celica forum was chinese....
 
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