100 series with a blown motor - options (15 Viewers)

[CapnSpaulding]

I bought a project LC. 2000 model with 206k. Got it for $2k and was under the impression it had blown the timing belt - sticker says 108k miles in 2008. The hood wouldn’t open at the time and for $2000 figured I couldn’t go wrong. I know….

Took it to my mechanic who scoped the cylinders and said the motor is trash. He found the upper radiator hose ripped and the radiator empty. His theory is they ran it til it overheated and the heat made the brittle old belt snap and from his view it’s likely melted some of the internals.

I towed it home disappointed and scoped it myself. Some cylinders look fine and some are dirty or have debris on top of the piston. One does appear to have some scoring.

What do you think I should do? Buy a used 2UZ, try to swap the timing belt and water pump on this one and hope for the best, or try to rebuild it?

I’m in Oklahoma, there aren’t any engines local so I’ll be out at least 3k on an engine and if I don’t do it myself, another 3k in labor. For 10k, seems like I could just buy a finished truck…. The interior and exterior on this one are a little rough, but no rust.

 

[Bisho]

So you’ve verified the timing belt it broken?

Heat is the number 1 killer of these motors, so a broken radiator hose does not bode well. You could buy an Aisin kit and new radiator hose for about $400 and give it a shot. Worse case you can put it on a used motor.

Remember, you can get a 2UZ from a Tundra, Sequoia or GX.

 

[2001LC]

I can't make much out of your pictures.

Timing belt break in 2000 4.7L 2UZ-fe, is not likely damaging.

If badly overheated, the heads warp. Coolant enters the cylinders and steam cleans piston tops even valve, if it kept running. Then, cylinder walls become badly scored. Block is them, not worth anything, unless bored. Which gets into a high $$ rebuild.

Best, find a used engine if cylinders are damaged. If you do R&R engine. Don't just buy any 4.7L. Be very careful, by reviewing history. Inspect with borescope, and get a compression test if a running engine. Many many sellers, claim low mile, when they're not. Get VIN #, from tag on Bk2 (Passenger side) head. Pull a carfax and look at Toyota or Lexus owners web page, at history. Do your homework.

 

[3_puppies]

a broken timing belt is not an issue on the non vvti engines, it is not an interference engine
X2 on heat /lack of coolant, being the issue

I would go the used engine route, used 2uz are not expensive do all the work while it is out and drop it in.

 

[Trunk Monkey]

I would check if the engine will manually turn over at the crank and do a compression test myself before spending money on a new engine.

 

[delz05]

Part it out if you are not able to drop in a used engine...

 

[CapnSpaulding]

So you’ve verified the timing belt it broken?

Heat is the number 1 killer of these motors, so a broken radiator hose does not bode well. You could buy an Aisin kit and new radiator hose for about $400 and give it a shot. Worse case you can put it on a used motor.

Remember, you can get a 2UZ from a Tundra, Sequoia or GX.

I checked this morning and the belt is NOT broken, so def was an overheating issue.

I’ve seen a few threads about the differences in the 4.7. It’s very tempting to grab an Iforce over the Japanese built 4.7. They’ve both proven themselves. I obviously like the actual JDM 4.7, but I’m not sure if it’s worth the premium over the tundra motor.

 

[2001LC]

Here's, some pictures of badly overheated engine. Which I've thread on " The Unicorn "engine R&R and more. You see pictures of cylinder wall scoring and more. Purchase The Unicorn unseen, as it was 2K miles away. I had a some hope, engine was okay. But once I had it and inspected. Found engine was trashed.

Warped head. We can see in this one, head gasket delamation.

As bad as this engine was overheated. I was able to change oil and clean up spark plugs, to get it started. It ran a few minutes. You can see combustion gasses, coming out coolant 90 degree hot hose to heat core tee.

Compression test.

Knock & VVT cam sensors and other plastic, melted

4.7 2UZ-fe VVt has plastic intake manifold, which melted also.

Coolant in oil

Hoses were brown for excessive heat. Even the alternator pulley show discoloration from heat.

 

[vipergrhd]

What have you done in regards to testing? Leak down test etc.?

 

[CapnSpaulding]

Here's, some pictures of badly overheated engine. Which I've thread on " The Unicorn "engine R&R and more. You see pictures of cylinder wall scoring and more. Purchase The Unicorn unseen, as it was 2K miles away. I had a some hope, engine was okay. But once I had it and inspected. Found engine was trashed.

Warped head. We can see in this one, head gasket delamation.
View attachment 4004135
As bad as this engine was overheated. I was able to change oil and clean up spark plugs, to get it started. It ran a few minutes. You can see combustion gasses, coming out coolant 90 degree hot hose to heat core tee.

Compression test.
View attachment 4004141
Knock & VVT cam sensors and other plastic, melted
View attachment 4004147
View attachment 4004142
4.7 2UZ-fe VVt has plastic intake manifold, which melted also.
View attachment 4004143
Coolant in oil
View attachment 4004144
Hoses were brown for excessive heat. Even the alternator pulley show discoloration from heat.

Thanks for posting! I did check out your thread and noted that yours looks far worse than mine. Interesting that mine will not start despite not looking nearly that bad.

 

[CapnSpaulding]

What have you done in regards to testing? Leak down test etc.?

I first brought it to my mechanic who scoped the cylinders and popped the timing cover. They didn’t go further based on what they said was deep scoring and possibly a crack in cyl 5. They said the piston heads are oblong now and overheated to the point it stopped running.

I did scope them myself and do see some scoring, but unsure on the depth and don’t see a crack and not sure about the oblong head shape, they look normal to me. I do see some debris on a few heads and one head is covered in burnt oil but that’s it.

I checked the timing belt myself and it actually looks fine and most importantly does not seem broken. I checked both sides and it looks fine. Could be broken at the bottom that I can’t see, but seems unlikely.

So, now I’m even more confused. When I try to start it, it sounds like it has no compression, sounds... flat. I only tried once as to not make it worse.

 

[CapnSpaulding]

I can't make much out of your pictures.

Timing belt break in 2000 4.7L 2UZ-fe, is not likely damaging.

If badly overheated, the heads warp. Coolant enters the cylinders and steam cleans piston tops even valve, if it kept running. Then, cylinder walls become badly scored. Block is them, not worth anything, unless bored. Which gets into a high $$ rebuild.

Best, find a used engine if cylinders are damaged. If you do R&R engine. Don't just buy any 4.7L. Be very careful, by reviewing history. Inspect with borescope, and get a compression test if a running engine. Many many sellers, claim low mile, when they're not. Get VIN #, from tag on Bk2 (Passenger side) head. Pull a carfax and look at Toyota or Lexus owners web page, at history. Do your homework.

Thanks for the info! The cylinders don’t look great but also not super clean or anything, it’s hard to tell with my crappy scope cam. I guess I can take the heads off before trashing the engine.

 

[CapnSpaulding]

a broken timing belt is not an issue on the non vvti engines, it is not an interference engine
X2 on heat /lack of coolant, being the issue

I would go the used engine route, used 2uz are not expensive do all the work while it is out and drop it in.

Yeah.. you all are right, the timing belt is intact and dept being 98k miles actually looks nice, it’s stamped Toyota so it was done at the dealer in 2008 with OEM parts is probably why.

It had to have overheated. It doesn’t look as bad as the other posted here that did still run, but I suppose it doesn’t have to be that bad.

 

[2001LC]

Yeah, bad borescopes, are difficult to see with. My first was a $20 drain snake. The borescope pictures you see in my thread, The Unicorn. Was a drain snake camera. But, You can see how bad the cylinder were scored.
A good cylinder looks like this:
See the cross hatch marks from factory honing. With just one minor vertical score line.

Make sure to turn crank, to get piston to bottom, in each cylinder as you're viewing it. Vertical lines (top to bottom, is scoring.
Wide lines and groups of lines, where you can not see honing hatch marks passing through them, is not good.
Trashed:

Piston tops or valve clean, not good. This one is steam cleaned, from coolant in combustion camber.

We normally see carbon build-up on piston, which is okay. See the cylinder crosshatch marks from honing, pass through vertical line (sores). This one is fine.

BTW: They sell some very good 8mm camera borescope, that are w/180 degree directional (Can look back at valves) for ~$100 on Amazon. Some have LCD, some just plug into PC and or smartphone.


Compression test:
Put a changer on battery, to keep fully charged while cranking engine. So you can crank engine at ~250 RPM, with all spark plugs out, throttle body butterfly wide open, fuel shut off (pull EFI fuse).

Compression test even in a cold engine, you'll see about 135 to 155 PSI in each cylinder. Ttwo cylinder next to each other, very low compression. Is head gasket issue or worst.

Next pressurize cylinder in a leak down test. Trick is, to get crank turned, so all valve closed in cylinder your checking/pressurizing.

 

[CapnSpaulding]

Yeah, bad borescopes, are difficult to see with. My first was a $20 drain snake. The borescope pictures you see in my thread, The Unicorn. Was a drain snake camera. But, You can see how bad the cylinder were scored.
A good cylinder looks like this:
See the cross hatch marks from factory honing. With just one minor vertical score line.
View attachment 4004254
Make sure to turn crank, to get piston to bottom, in each cylinder as you're viewing it. Vertical lines (top to bottom, is scoring.
Wide lines and groups of lines, where you can not see honing hatch marks passing through them, is not good.
Trashed:
View attachment 4004256
Piston tops or valve clean, not good. This one is steam cleaned, from coolant in combustion camber.
View attachment 4004255
We normally see carbon build-up on piston, which is okay. See the cylinder crosshatch marks from honing, pass through vertical line (sores). This one is fine.
View attachment 4004257

BTW: They sell some very good 8mm camera borescope, that are w/180 degree directional (Can look back at valves) for ~$100 on Amazon. Some have LCD, some just plug into PC and or smartphone.


Compression test:
Put a changer on battery, to keep fully charged while cranking engine. So you can crank engine at ~250 RPM, with all spark plugs out, throttle body butterfly wide open, fuel shut off (pull EFI fuse).

Compression test even in a cold engine, you'll see about 135 to 155 PSI in each cylinder. Ttwo cylinder next to each other, very low compression. Is head gasket issue or worst.

Next pressurize cylinder in a leak down test. Trick is, to get crank turned, so all valve closed in cylinder your checking/pressurizing.

Thanks again, this is very helpful. Unfortunately some of my cylinders have this similar vertical scoring. Perhaps that’s what the mechanic saw too and just didn’t describe it well.

 

[vipergrhd]

I got my long block from this website, I got lucky to find a low mileage engine out of a Seqouia. 185k miles and very clean inside.

Search Results

I bought mine very similar to yours thinking I was able to salvage the engine, I happen to stumble on this on CL.

 

[CapnSpaulding]

I got my long block from this website, I got lucky to find a low mileage engine out of a Seqouia. 185k miles and very clean inside.

Search Results

I bought mine very similar to yours thinking I was able to salvage the engine, I happen to stumble on this on CL.

What all did you have to swap over? I’ve seen a few thread but nothing concrete: oil pan, and throttle body?