We finally got the big end bearings out of the 1HD-T and the centre two look like new. My diesel mechanic buddy said leave them after a quick plasti gauge measurement.
I mentioned thier were problems with the bearings and wanted to replace them anyways.
Turns out the two at either ends of the block were slightly scored and showed signs of small particles in them?
We installed the new ones and did a quick measure and they were dead on.
My schooling for the day was telling me what the bearing shells are made of, First layer is steel, second is copper and the third layer which is in contact with the crank is babbit. He mentioned the babbit is like a sponge and will absorb any impurities plus it holds the oil longer againts the crank.
John also mentioned that the oil between the shell and the crank is more like millions of ball bearings. I always thought of it as a film and he claimed if it were a continous film thier would be to much drag?
Learn something new everyday.
And the factory torque is something he has never run into, 27 FT pounds and then you turn the rod bolt exactly 90degrees.
Yep, there was one bearing of all six which was damaged. Not to the extent of the really chew units, more like the ones on the side page which look like flakes let loose.
Anyways, its really strange how one showed this type of failure and the rest looked like new. In fact a diesel mechanic came by tonight and after viewing the bearings suggested not changing them.
He had never seen a big end bearing fail in that way and thought someone had damaged it in assembly.
We changed out all the bearings and check clearance, 2 thou across the board. Damn good machine work on toyotas part. And to mention if you want to change the water pump on a 1HZ or HD-T you have to pull the timing belt off and cam shaft seal retaing housing, reall PITA.
Good call on changing the clutch and water pump Tom as the clutch was done and the water pump although not leaking was very tight.
Another plug for OTC, the engine stand with gear head rocks as I can spin the motor with one hand. Went to my friends house to help him rotate his 454 on a old school stand, not a easy task for two people.
Thanks for the link to that web page, good to see the exact same damage so I know what to look for.