Is my bottom end toast? (1 Viewer)

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So far I took appart 4 3B, 2 pre1985 , 2 post 1985.
The pre 85 have two hole on top of the conRod to cool piston (idle) and lubricate the wall instead of one on the post85… which leave a little less oil for the wrist pin.

Might be a coincidence but. the wrist pin were really worn out on the older. Even at 400k km the 1986 were not too bad.
All of them were NA
I would be more concern about preventive maintenance on older 3B, specially on a turboed one.

A crankshaft running low on oil pressure make hot spot on bearings, kind of melt the antifriction material and eventually seize, won’t turn after. The crank shown signs of increased temperature, turn blue, mini fracture.
 
One thing I've been curious about with the 3B is the automatic timer on the end of the camshaft. It uses some springs and weights to adjust injection pump timing with engine speed. As they wear out do they tend to advance timing or retard it? Doing the static pump timing procedure as specified in the FSM doesn't take into consideration possible impacts of a worn automatic timer.

It would be nice to modify one with shims or springs to limit total advance for a 3B with a turbo.
 
So far I took appart 4 3B, 2 pre1985 , 2 post 1985.
The pre 85 have two hole on top of the conRod to cool piston (idle) and lubricate the wall instead of one on the post85… which leave a little less oil for the wrist pin.

Might be a coincidence but. the wrist pin were really worn out on the older. Even at 400k km the 1986 were not too bad.
All of them were NA
I would be more concern about preventive maintenance on older 3B, specially on a turboed one.

A crankshaft running low on oil pressure make hot spot on bearings, kind of melt the antifriction material and eventually seize, won’t turn after. The crank shown signs of increased temperature, turn blue, mini fracture.

On a lot of the Toyota cranks the blue color is a heat hardening treatment from manufacturing, not from bearing failure/heat. I did a double take first time I saw this too. Here is a 2LTE crank for example.

IMG_20210925_095331105.jpg
 
On a lot of the Toyota cranks the blue color is a heat hardening treatment from manufacturing, not from bearing failure/heat. I did a double take first time I saw this too. Here is a 2LTE crank for example.

View attachment 3034110
Well yes you are right about this color created by local hardening. I was thinking something else, where the journal bearing become blue itself, not the crank web.
Thanks
 
Well yes you are right about this color created by local hardening. I was thinking something else, where the journal bearing become blue itself, not the crank web.
Thanks

Ahh, sorry, I misunderstood.
 

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