5VZFE Engine Noise

[the kid]

how many miles on your motor? and how many of those was it SCd? i notice you have a 2nd gen SC on your T100... so it wasnt SCd from new. i have been wanting to SC my runner for some time, but this is my fear, adding forced induction to an older motor will really bring it to an early grave. id like to get a SC and then rebuild a second motor to just do a plug and play swap to get more power -might even do a full trans swap too at that time with a build torque converter and upgraded valve body. that way i know the drive train will be up to holding the added power.

sucks to see this, -dont you wish it was my theory of the knock sensor wire harness lol -in all honesty the sound on my computer does not work -laptop too a dump on me had it "fixed" but the sound card does not work nor can i watch youtube videos so i was only going by what you described and the code you gave, im sure the sound would have been more telling.

 

[Arclight]

It's hard to say as I bought it used with no records at all. But the truck has 210K now, and the Supercharger plumbing looks to be nice, fresh rubber and newer than the rest. The rest of the engine did not have any problems I could find - all the other cylinders still have excellent compression and leakdown values, and I drive with a pretty light foot.

I'm still not totally sure what happened with that rod bearing, but it does look like a set of main bearing shims may have failed first. I pulled another bearing, and it showed little wear. The knock came on suddenly too.

Arclight

how many miles on your motor? and how many of those was it SCd? i notice you have a 2nd gen SC on your T100... so it wasnt SCd from new. i have been wanting to SC my runner for some time, but this is my fear, adding forced induction to an older motor will really bring it to an early grave. id like to get a SC and then rebuild a second motor to just do a plug and play swap to get more power -might even do a full trans swap too at that time with a build torque converter and upgraded valve body. that way i know the drive train will be up to holding the added power.

sucks to see this, -dont you wish it was my theory of the knock sensor wire harness lol -in all honesty the sound on my computer does not work -laptop too a dump on me had it "fixed" but the sound card does not work nor can i watch youtube videos so i was only going by what you described and the code you gave, im sure the sound would have been more telling.

 

[zolo]

In your photo of the thrust washers it looks like one of the tabs broke and then the whole set spun out and that would cause the crank to walk all over the place.
I'm surprised that all you ended up destroying was a rod bearing.

I know a lot of folks have stated they would do a motor swap. But that is very involved to do right.
What about rebuilding what you have but in a manner to gain more power. Build your motor with lower compression and then raise the boost.
If there is a different pulley available that is.
What PSI are you running now? If you built the engine to handle the boost you would gain a lot of power. Plus a good amount of torque to help out.
This is just a thought.

Once the bottom ends comes apart its time to start from square one.

 

[Arclight]

I did an engine swap years ago (62 Chevy II) and I don't think I want to do that again. It was a lot of work, for a simple vehicle like that. Bolting it in is the easy part - getting every wire, accessory, etc rerouted and spliced in is the hard part.

For this one, I think I first want to figure out why it failed. It sounds like those shims are basically thrust washers for the crank. I'm going to guess those failed first. And then crank end play started working on the #2 rod, which is at the front. Doing some research, it sounds like excessive automatic transmission pressure can overload the thrust bearings, as can improper clearance on the torque converter or alignment issues. I think I'll check on this before I tear it all the way down.

http://www.4secondsflat.com/Thrust_bearing_failures.html

As for an increased power rebuild, I'll give that some thought. It's pretty adequate with the setup I have now, and I'm pretty sure I'd need the 7th Injector and probably other mods to make use of more boost safely.


Arclight

In your photo of the thrust washers it looks like one of the tabs broke and then the whole set spun out and that would cause the crank to walk all over the place.
I'm surprised that all you ended up destroying was a rod bearing.

I know a lot of folks have stated they would do a motor swap. But that is very involved to do right.
What about rebuilding what you have but in a manner to gain more power. Build your motor with lower compression and then raise the boost.
If there is a different pulley available that is.
What PSI are you running now? If you built the engine to handle the boost you would gain a lot of power. Plus a good amount of torque to help out.
This is just a thought.

Once the bottom ends comes apart its time to start from square one.

 

[zolo]

I did an engine swap years ago (62 Chevy II) and I don't think I want to do that again. It was a lot of work, for a simple vehicle like that. Bolting it in is the easy part - getting every wire, accessory, etc rerouted and spliced in is the hard part.

For this one, I think I first want to figure out why it failed. It sounds like those shims are basically thrust washers for the crank. I'm going to guess those failed first. And then crank end play started working on the #2 rod, which is at the front. Doing some research, it sounds like excessive automatic transmission pressure can overload the thrust bearings, as can improper clearance on the torque converter or alignment issues. I think I'll check on this before I tear it all the way down.

http://www.4secondsflat.com/Thrust_bearing_failures.html

As for an increased power rebuild, I'll give that some thought. It's pretty adequate with the setup I have now, and I'm pretty sure I'd need the 7th Injector and probably other mods to make use of more boost safely.


Arclight

That is correct the pieces you asked about are thrust washers for the crank. I responded earlier with a photo of what they look like when in place. So you can see when they get damaged and shot out of place what can happen is dramatic to say the least.

Its sounds like you are on the right track. However discouraging this is now, buy the end of the repair you will have a truck with better power (even if you dont raise the psi) and a lot of life in it.

Good luck and don't get to down about it. Sounds like you are a savy guy and will have your truck repaired in no time.

 

[paddlenbike]

For me, I'm loving the 4.0. Excellent power and decent economy. Going from my 3rd gen 4runner to a 4th gen felt like I was going from a tractor to a race car!

Going from a supercharged 3.4 to a naturally aspirated 4.0 would be a downgrade, in my opinion. I get good mileage and power from my SC'd 3.4 and I can't really think of another engine that would provide the same power along with significantly higher economy. What happened here is an anomaly. You are doing the right thing by inspecting the existing bottom end to determine what kind of damage was done (scoring on the crank, rod end or possibly even scoring on the cylinder walls if the crank walked), and either rebuilding the bottom end or going with a low mileage shortblock replacement. I've had a rod bearing go bad and no damage was done to either the crank or the rod. Either way, while the heads are off, have them vacuum tested and valve stem seals replaced. Then you'll have a completely refreshed motor without a significant investment or have the headaches of a motor swap. Just my .02.

 

[Arclight]

So it looks like the machine shop I got referred to by my mechanic friends here can rebuild my existing short block and heads for $1600, and will pick up and deliver for me. So far, this seems like the best option. I was looking at $1100-1600 for a used JDM motor of unknown provenance.

I'll be renting an engine hoist tomorrow (about $35) and getting the motor out so it can go in on Monday. I'm going to order new timing components and external seals from my Toyota guy (Toyotapartsman in GA) and reuse the ~5K water pump and idlers if they look OK.

I'm figuring about $500 for miscellaneous parts and fluids, plus the rebuild.

Since I'm not sure if the thrust bearing killed it, I'm going to give the grounding system, transmissions lines and flex plate clearance a good look while I'm tearing it down.

Does anyone have anything else to suggest while I'm in there?


Arclight

 

[paddlenbike]

That is a very good price for both a shortblock rebuild and a head refresh. It's likely the only thing the head will need is valve stem seals (which I would do regardless of their condition) and check the valve lash. Oh, might want to replace the cam seals while you're at it.

Do you know if he's planning on using OEM Toyota bearings? A new oil pump would be a good idea since yours has seen metal shavings. Other than that, sounds like you're good to go.

 

[Arclight]

I managed to get the engine out and stripped down to a long block today. And my overhaul kit is on order from Toyotapartsman. It should go into the machine shop this week. Here's a pic. It's sitting sideways just so I could show more of it.



You'll have to zoom in to see it, but I discovered a neat trick if you need to make a lifting sling. My wife and I rock climb, and we had some bolt hangers laying around. One of these will bolt right up to a Toyota head with the usual 8mm bolt, making for a nice secure place to attach the chain.






Arclight

 

[Wainiha]

I'm interested in the final diagnosis.

 

[the kid]

while you have it out, look at putting some headers on it, cause nows the time to do so, otherwise youd have to pull the motor again to do that, and headers with the SC, man that will liven up your motor right there!

 

[Arclight]

Good news - the truck is operational again! I had a local machine shop pick up the stripped long block and do a full top and bottom end rebuild. I ended up buying a Toyota overhaul gasket set, oil pump, water pump and timing parts, and letting them source everything else. I also replaced the radiator and a few miscellaneous things, cleaned and painted, and changed the oil in the supercharger. I ended up with an .020 overbore, and the crank and one rod were not salvageable.

I've now put about 650 miles on it, and it's running great.

In typical Murphy's Law fashion, the knock sensor code I saw right before the teardown came back to haunt me. I had figured it was a knock sensor harness (the old one was heat damaged and very cracked), so all I did was continuity-test the sensors before reinstalling them. Well, it turns out that one of the microphones really was bad. So I ordered a new Denso knock sensors and a gasket set from Rock Auto ($180 total), spent about 3 hours working on it, and successfully banished the CEL.

Thanks everyone for the help!

Arclight

 

[deadbeat son]

Awesome! I'm glad to hear you were able to get it back together and it's running well.

oil pressure (always reads lowish on this truck)

Just out of curiosity, did the rebuild change this, or does the pressure still read lowish?

 

[Arclight]

Yes, the oil pressure gauge reads much differently. It stays at about 1/4 at idle, and goes up predictably with RPM. It never did that with the old engine, so I suspect it had worn bearings and/or oil pump. I went ahead and had a transmission shop check the line pressures as well, since one of the possible causes could have been the AT.

Arclight

 

[deadbeat son]

Yes, the oil pressure gauge reads much differently. It stays at about 1/4 at idle, and goes up predictably with RPM. It never did that with the old engine, so I suspect it had worn bearings and/or oil pump. I went ahead and had a transmission shop check the line pressures as well, since one of the possible causes could have been the AT.

Arclight

Good to hear. I didn't read your thread until this morning, but that part had me wondering if it was the cause of your issues.

Regardless, congrats on getting it back on the road!