SOLVED! Post 2853 Leaking Injectors, Dealer Techs Rock! Extended Cranking after Engine Swap 3.4L 5vz

Check it out guys! A couple of the white ones and one of the red ones just got back from ! And I used a toothpick to write TRD on a black one to look like our Taco! Hope they like 'em! Wish you all lived nearby so I could give you some too!

 

just drop one in an envelope and mail em to us lol.

you will now be seen as "that really nice lady" at the shop

btw I understand how you feel on the injectors and wanting to trust him. I still think it would be better to have bought the 4 hole upgraded injectors and had him install them but the less efficient stock injectors will still work fine as long as they are all cleaned good.

 

quit being so greedy and share the cookies bro!

 

Aww, thanks guys! Hurray, so ya think the cookies will change my title from crazy electrode lady to really nice lady?

 

No.

 

I did say to mail "us" a cookie so im assuming we each will get one as long as the drug sniffing dog at the post office doesn't eat them first lol,

there was a local story just the other day about a dog eating into somebodies box of baked Christmas goodies they mailed so he got sent back to doggy training school. poor guy was just hungry, lol.

I think so, or at least get you a bump up to the really nice crazy electrode lady

 

Well it would be hard to mail a single cookie to us all. I say she makes half a dozen for each of us! Hahaha.

 

Poor dog! He was hungry! : )

I'll take really nice crazy electrode lady, that's a step up, right? : )

 

Do you guys think it's possible the piston top was hot but did not have a hole yet, then the area got so hot that the electrode smashed through and created the hole? Or is it more like the heat would have caused the hole first, then the electrode disappeared as an aftereffect?

If shipping were free, you'd all be getting truck cookies for Christmas! Sorry guys. Instead I'll share some fun little dudes:

 

the top of the piston does have some thickness to it but in the range of maybe 1/4" thick so looking at the hole, it was the center most flash point like a cutting tourch tip that melted its way slowly through to form the hole. I don't think the hole was made by the electrode or anything loose in the cylinder.

I suppose the hole might not be all the way and it could be just about on the verge of blowing through and maybe still be very thin but still holding compression.

there is a gap between the piston and head (about 1/8" or so usually) plus the crowned part, so it most likely pulverized the electrode into dust that was melted or simply pounded into the head, or escaped through the exhaust valve in dust form. im sure it was a combination of all that.

I realize you think you should find the missing object somewhere but its more uncommon then not to find something like that intact.

the engines I have seen when things get loose in the cylinders mostly look like you took a hammer and chisel and gouged the hell out of the head and valves so it looks like something resembling a moon scape. my bet is they will find whats left of the missing plug embedded into the head when its removed, often it can be knocked off and removed since it just hammered together.

or its very possible even though rare, that the electrode simply melted itself away as it also melted its way through the piston

 

Thanks Keakar. So do you think it's virtually impossible that we might have been able to retrieve the electrode from the top of a hole-free piston if we'd shut Taco off when noise started, then IMMEDIATELY pulled #3 plug, then borescoped/used a magnet to get it out? Or is it just one of those things where anything's possible but it's not likely, and we'll never really find out for certain?

(meaning, as opposed to starting it for ~10-15 seconds at least 2-3 times, and THEN investigating #3)

 

I preface this by saying it is only an online video and the noise could be different sounding in real life.

Ive heard that type of engine noise many times. On newer Toyota engines the quench area has some very tight tolerances. When you have carbon build up along with a bad rod bearing it allows the piston and cylinder head to make contact. That "upper end contact" is loud enough to mask the lower end engine noise. If you listen in the video, the noise changes right after startup, from low to high end. Typically you can not isolate the noise with a cylinder balance test unless you really listen for a tone change as the piston will still hit the head.

This noise started becoming common with engine failures in post 95. It happens when the bearing is so far gone that the centrifugal force allows the "extra" movement of the piston. I have heard it on older engines that have had the deck machined but it is not as common.

 

Google "quench area" if you want to know about piston to head clearance and the theory behind it.

 

So are you thinking we've got a spun rod bearing as well as the piston hole? Hmmmmm. And you said you've heard it on older engines that have had the deck machined - what's the deck? Is that the block?

Dirty Pool, googling now.........although I gotta say, it's way more interesting to read all of your responses to my wacky questions!

 

Ah, this quench area google search is right at the heart of our issue! Thanks for the tip Dirty Pool!

 

some people use different terminology for things but I think deck machining is having the block resurfaced but even if its the head, this does not apply to your engine because it is stock and hasn't ever been rebuilt before

once they pull the head they "might" find it pounded into the head or maybe not but they should be able to form an idea as to what happened to it, as in a best guess at the very least as to weather it is stuck in there somewhere, simply melted away, or was pulverized and worked its way out of the engine

 

The head and piston will not really look that deformed. It will be clean with markings on it. There will be light evidence of impact, no where near what you would think though.

When I refer to the deck, I'm talking about the block mating surface for the head gasket. You are right, it is not a concern for her as she has an OEM block/build.

I'll look for the scope pictures again, the 1st ones I saw were not really readable, that I noticed, I'll look for them again.

Like Bama, I'm a Master Diagnostic ASE Technician. I have been exclusive to Toyota though. I've worked for Toyota for 16 years starting with the T-ten training program through Toyota.

 

Derp, that was a video, not a picture, kinda went full retard there. I watched it, it looks like a hole but that camera is horrid. That still does not explain the knock. If you look around the sides of the piston it looks like a silver ring in some areas indicating contact. It is so hard to tell.

This is the tool I use to look in the cylinder, it has really good imaging and lighting.
https://store.snapon.com/Video-Scopes-Video-Scope-Digital-Wireless-P742121.aspx

 

I guess we are both still waiting...I got a call from the mechanic yesterday afternoon on the vintage 4runner. They had put the motor back together, and now it won't start I suspect they are finding the ignition issues I ran into two years ago when it started failing electronic ignition fuzes. This started out as a passenger side valve cover job and it has expanded to timing belt, crank seal, cam seal, wiring harness repair and now distributor/igniter issues. Oh well, we gain little by deferring work.

Howard

 

Thanks for the input guys. Anxiously awaiting updates from mechanic, hoping he'll call today! Hope you get a good update soon Hetkind!