stall droped from 4600 to 2800?

[oldguy]

we lost 2000 rpm on stall, checked valves, leaked motor, checked w.g., checked vanes on hot side of turbo, 31 box, big stuff logs. a/f is @ 12.8--13.0,
t.b. is opening, plugs are good, no exhaust leaks are evident. need some help trouble shooting. anybody?

bob coffman

 

[bison]

Broken sprag in converter

 

[oldguy]

tranny builder says convertor is fine. we had him check it on bench.

 

[bison]

tranny builder says convertor is fine. we had him check it on bench.

How did he check it?

 

[Alky V6]

Plugged exhaust? Cat?

 

[oldguy]

it's a built motor -- no cat, 3 feet of 5" exhaust, w.g. closed.
what's left?

 

[Alky V6]

Has the timing been manually checked?

Checking a converter on the bench without cutting it open is not the most precise way of checking it.

 

[oldguy]

timing was synced and checked--okay. it revs normally in neutral.
can't think of anything else except converter going away. any more thoughts?

 

[bison]

timing was synced and checked--okay. it revs normally in neutral.
can't think of anything else except converter going away. any more thoughts?

Can you post any data logs? Seems like the converter failed to me. No torque multiplication.

 

[oldguy]

tried 2 high stall converters-----same result. stops at 2800 rpm. i'm thinking tranny man was mistaken. 2 hurt converters.

 

[Alky V6]

tried 2 high stall converters-----same result. stops at 2800 rpm. i'm thinking tranny man was mistaken. 2 hurt converters.

Have you tried a known good converter?

 

[oldguy]

ran out of high stall converters for t400

 

[Alky V6]

I have to say that the chances of 2 torque converters failing in the same manner and giving the same stall speed is rather slim.

 

[oldguy]

totally agree! that's why we chased everything else so meticulously. i guess we send out the converter. thanks fellas

bob

 

[chris718]

Did you check to see if the stator tube spun in the pump cover?

 

[Dusty Bradford]

Did you check to see if the stator tube spun in the pump cover?

+1 on what Chris said. Check to see if the stator support can spin.