int. shaft/ oil pump gear issue

[mo' parts]

ive seen alot of threads where this has happened (gears getting chewed up), but not many explain as to why.

it was freshened up 2.5 CB that i dis-assembled and re-assembled. i plastigauged it when it came apart and when going back together, everthing checked out great.

i had some fuel diluted oil in it for about 50 miles or so, as i had forgotten about the no spark issue i had back in october. i changed it and oil press was still pretty good about 50+ cold and 10-15 psi hot idle, and pretty much spot on with the 10psi per 1000rpm. i did have a slight oil psi drop over the next 2-300 miles, but still within spec and no bottom end noise, jusy slight top end noise.
i had also been fighting a upper rpm miss that i just couldnt get a grip on. while trying to find the miss, i did notice a bit too much play in the rotor button and the shutter wheel was tight. sine the tracks are getting ready to open i figured it be a good idea to drop the pan and have a look see. now, the engine still ran fine, no knocks, nothing out of the ordinary.
man, if i would have waited any longer the motor would be junk. all 4 rod bearings were wasted and the #3 main was toast. The no.3 main cap was black, is it no longer any good? or just a line bore on the block?
when the pump came down it was obvious, the hourglass shape and chewed up gears says it all.

But what is usally the cause of this?
I guess thats what i get for re-using the old pump.
Here are some carnage picts, enjoy.

[86Shelby]

Ouch!!! Good thing you didn't take it to the track and scatter it!

[inmyshadow]

My several failures were caused by the removal of the balance shafts. With no balance shafts and 2.5 pan means no more oil control. I would oil starve in hard left turns.

After a few pumps/gears, a wise man said. Whynot go with a 2.2 CB pan and pick up. After that, I need another failure.

My current shadow, the previous owner had already removed the oil pan. So I babied the car around turns. Until I got the TU baffled oil pan.

later

[turbovanman²]

I always reuse the stock oil pump and haven't had any issues.

Did you inspect the teeth for obvious wear, pitting? That will of course do it.

Is the pump hard to turn? Did you leave the screen on the oil pump pickup?

I think its existing wear, oil sloshing around as stated, I did make my own baffled pan and maybe bad bearing alignment/wear for the int int shaft. Was the oil pump properly installed? I've also seen them mounted at an angle,

Fuel dilution killed my last TIII, it doesn't take long,

[mo' parts]

Ouch!!! Good thing you didn't take it to the track and scatter it!

exactly, an oil pan gasket and an hours time is cheap insurance.
i was about to take it to northern ohio for our buckeye chapter meet on the 4th, that would have been an expensive tow.

[mo' parts]

My several failures were caused by the removal of the balance shafts. With no balance shafts and 2.5 pan means no more oil control. I would oil starve in hard left turns.

After a few pumps/gears, a wise man said. Whynot go with a 2.2 CB pan and pick up. After that, I need another failure.

My current shadow, the previous owner had already removed the oil pan. So I babied the car around turns. Until I got the TU baffled oil pan.

later

i do take some corners pretty hard, and the balance shafts were removed.
i just got back from picking up a complete 89 t2 motor and 89 555, so that solves the pan issue, and the 87' 520.
i guess this block will go to the shop after i get done drilling and tapping for a hybrid
thanks for the info.

[mo' parts]

I always reuse the stock oil pump and haven't had any issues.

Did you inspect the teeth for obvious wear, pitting? That will of course do it.

Is the pump hard to turn? Did you leave the screen on the oil pump pickup?

I think its existing wear, oil sloshing around as stated, I did make my own baffled pan and maybe bad bearing alignment/wear for the int int shaft. Was the oil pump properly installed? I've also seen them mounted at an angle,

Fuel dilution killed my last TIII, it doesn't take long,

Simon,

i did check for excessive wear on both the shaft and pump and all was well. ive never had a problem re-using a semi high mileage oil pump before.
the shaft bearings looked really good and the pump was mounted properly. the screen was in place, though upon removal it seemed as though the pick up tube may have had a little slop where it bolted to the pump, even though it was torqued properly. the pump was a little hard to spin after removal.

[turbovanman²]

I wonder if the bearings started to go on the int shaft.

Maybe the fuel didn't help, I know it took a few runs and my engine was done,

[mo' parts]

I wonder if the bearings started to go on the int shaft.

Maybe the fuel didn't help, I know it took a few runs and my engine was done,

im guessing it was a combination of the oil and my hard driving that initally did it in.
what about the main cap? do you think its re-useable? its black, so it got awefully hot. the bearing was just starting to spin, about an 1/8 in.
when the oil returns to the block from the filter, where is the first place it goes? the main bearing galley feed?

[turbovanman²]

im guessing it was a combination of the oil and my hard driving that initally did it in.
what about the main cap? do you think its re-useable? its black, so it got awefully hot. the bearing was just starting to spin, about an 1/8 in.
when the oil returns to the block from the filter, where is the first place it goes? the main bearing galley feed?

Black should be ok, its when it turns blue or burns the oil off.

If the bearing started to spin, I would say its junk, so either another block or a line bore, which isn't cheap.

[mo' parts]

Black should be ok, its when it turns blue or burns the oil off.

If the bearing started to spin, I would say its junk, so either another block or a line bore, which isn't cheap.

thanks simon, i have another motor ect, so its fine. i was planning a hybrid motor for next season, so a line bore will be in order
how much does something like that usally cost, ballpark?

[turbovanman²]

Line boring varies, around here, I seem to remember around $400, align hone is $150.

[mo' parts]

Line boring varies, around here, I seem to remember around $400, align hone is $150.

Cha-Ching!!!!