Is my bottom end toast? (1 Viewer)

[theglobb]

I was driving down the highway in my 3B powered BJ75 when all the sudden it felt like my tranny popped out of gear. When infact it didn’t, just felt like something broke free and then a loud knocking noise started coming from my engine. Does anyone have any idea what could be causing the noise?

 

[Gimme a 60]

Sounds like it could be…. Probably rod knock.

Now -how many kilometres on the engine, and much PSI are you running on the turbo?

 

[theglobb]

Sounds like it could be…. Probably rod knock.

Now -how many kilometres on the engine, and much PSI are you running on the turbo?

340,000 kms, and up to 15psi but usually around 10-12. Rod knock/spun bearing was my guess

 

[Gimme a 60]

340,000 kms, and up to 15psi but usually around 10-12. Rod knock/spun bearing was my guess

Wow. That’s low KM. These engines are supposed to run forever. Real shame, I don’t have much else to say than good luck on finding a replacement/parts.

 

[theglobb]

Thanks, I’m just as surprised as you are. Literally no warning signs at all and then boom, gone

 

[Gimme a 60]

I pulled my 3B in a couple days. Pretty easy, wouldn’t hurt to drop the oil pan a have a look.

 

[lacalvette]

Ouch might be a dropped piece of precups too.

 

[LDowney]

I must have bad hearing because I could not discern anything clearly troubling from the video.
You are there and identified a difference immediately, so that is more telling.

Pulling the pan to start your inspection/assessment sounds like your best place to start.
Keep us updated.
The timing could not be worse with your plans. Good luck that it is not major.

 

[theglobb]

I must have bad hearing because I could not discern anything clearly troubling from the video.
You are there and identified a difference immediately, so that is more telling.

Pulling the pan to start your inspection/assessment sounds like your best place to start.
Keep us updated.
The timing could not be worse with your plans. Good luck that it is not major.

Can you hear it more in this video? It's very noticeable in person. I've pulled the pan, will look more into it all tomorrow.

Very bad timing with my plans for a trip to Montana, glad it happened now vs on the trip

 

[LDowney]

With the pan off, can you feel any abnormal play? See anything odd in the engine or in the pan?
It is unlikely that there was anything in the oil either? [other than expected high level of carbon]

 

[The Machinist]

Ouch might be a dropped piece of precups too.

My first thought was a rod bearing, but if it happened suddenly with a noticeable thud then this might just be what happened. Might not be a bad idea to pull the glow plugs and put a borescope down into the cylinders to see if there is any junk bouncing around.

 

[RufusTheDufus]

The noise and experience is very similar to what happened to my 3B when I broke a crankshaft.

Crack or casting mark?

 

[ZCissner]

The noise and experience is very similar to what happened to my 3B when I broke a crankshaft.

Crack or casting mark?
View attachment 3031187

thats going right through a machined surface, im thinking its cracked right in half

 

[theglobb]

Yup, crank is toast, pieces. WOW wow wow wow.

 

[theglobb]

If y’all want I’ll be doing most of the updates in my build thread for the Red Rocket and if anyone has any leads on a 3B or even 14B for sale in America (preferably east coast) let me know!!! Sucky situation

 

[Gimme a 60]

I’m so shocked. I have no idea how that would crack that bad. Not impressed.

 

[GTSSportCoupe]

This is one of many 3B's with turbos added that have broken cranks on this forum. There is a theory that folks should be retarding the injection timing a bit to reduce stress at the crank. Turbo heat/pressure means diesel ignites faster after injection I think? Sort of like pre-ignition in a gas engine. Very hard on everything when pressures are too high too early.

My computer controlled 2LTE pulls a ton of timing when the air intake temps get hot. When cold, it pulls hard though. Toyota clearly recognizes this is an issue. 3B would have had timing specs based on normally aspirated function, not turbo.

If I had a turbo 3B, I'd pull timing back a bit just in case.

 

[theglobb]

This is one of many 3B's with turbos added that have broken cranks on this forum. There is a theory that folks should be retarding the injection timing a bit to reduce stress at the crank. Turbo heat/pressure means diesel ignites faster after injection I think? Sort of like pre-ignition in a gas engine. Very hard on everything when pressures are too high too early.

My computer controlled 2LTE pulls a ton of timing when the air intake temps get hot. When cold, it pulls hard though. Toyota clearly recognizes this is an issue. 3B would have had timing specs based on normally aspirated function, not turbo.

If I had a turbo 3B, I'd pull timing back a bit just in case.

I did, about 11 degrees if I recall. Probably helped but I guess not enough... Good information though for anyone who might be wanting to turbo a 3B in the future

 

[GTSSportCoupe]

I did, about 11 degrees if I recall. Probably helped but I guess not enough... Good information though for anyone who might be wanting to turbo a 3B in the future

Wow, interesting. I wonder if the cranks just can't take the power, or maybe timing needs to be pulled even more (ideally just at high loads).

Is the 3B crank same as 13BT crank?

Would be interesting to compare timing specs turbo vs. NA of some of the mechanical injection IDI diesels Toyota made. 1HZ vs 1HZ-T, 2L vs 2LT for example.

 

[roscoFJ73]

Wow, interesting. I wonder if the cranks just can't take the power, or maybe timing needs to be pulled even more (ideally just at high loads).

Is the 3B crank same as 13BT crank?

The same , but the gudgeon pins are way larger(wristpins) and con rods, at about 4.00