Installing new Rod bronze bushings

[MarsaGSX]

Got use old Crower rods and wanna install new crower alu-bronze bushings..
So ordered 5 new pieces from Crower and let the bushings installed...
First off we used press to uninstall old ones..was straight and okay...then we put rods on table cooker to warm it..Got laser thermo meter..so we checked the temp the table cooker can produced..and was 400deg of Celsius..So like 13520°F Anyway I turned down the temp to like 300°C..
Of course bronze bushings was on the freezer..

Then simple put rod on press..put on new bushing and pressed..but from 2..maybe 3 of bushings went grinds..So the bushings wasn´t in center hole of rods. Then I went to machine shop to grind inside diameter to my piston pins..to fly inside..diameter was 21H6 I think..can´t remember now..
Anyway..after two days went for finished rods and checked them..and found the grind marks wasn´t 360deg around..So the bushings wasn´t really in Center holeinside So on one rod where the inaccuracy was biggest I uninstall the bushing and put in the 5th bushing I bought as spare.. but now I used table cooker to the max..400+°C. The rod sit there for maybe 15mins..not sure..myabe longer..anyway I was able to hold the rod on big end with just duster..
then put on press..put on freezed bushing(this time the bushing went inside with just finger press for like 3mm..so was on center..then pressed inside..

BUT check up the pics..the rod gets BLUE color...Is it okay?? When the temp was like 300°C wasn´t able instal the bushing correctly..and when heat up like 420..430°C.. is BLUE..
I know structure of steel..iron is changing after 1500°C 50700°F So I couldn´t change structure..
Iam about order new bushings from Crower and resinstall them with higher tem of 430°C= 14534°F

Anyone changed the small end bushings??Any tips to this??

Thank you very much..
BTW Czech race seasson starts next week..So Iam not able launch on the session .. Iam sooo.. bored and angry..

 

[MarsaGSX]

Received email from Crower tech support

Hi,

The way you install our bronze bushings requires NO heating. 2.5 to 3
thousands press is all you need. Then re-hone your rods with the bushing
installed to desired wrist pin size.



Hell.. this way I wasn´t able install bushings in CENTER of small end..

 

[MarsaGSX]

So is here anyone who can tell me DON´T USE THIS RODS...I will order Eagle rods and tadaaa...
Or its okay..No problem..

I put my rods onto table cooker..warm on 450°C like 842°F put in new bushings and all looks okay..but then I take my rods to machine shop to reaming SE inner dia to float the pin and the machine man told me the rods are gone..when I heat them up to 450°C...told me I will broke the SE cus of my target power.. rev 9K and max out 35R with 1.06AR hotside.

I don´t know what temperature needs to change inside material structure..So not sure if those 450°C changed rod mate itself..

Of course its like 4days I wrote email on Crower tech help..still no answer...

Thank you guys


Venca

 

[pneumo]

That's a tough question. I haven't seen a question like this on these forums. My first reaction is that the rod has changed somehow, and if it's different then maybe it shouldn't be trusted.
My second reaction is to Google it and find the answer. This page was very helpful: Furnaces for the Thermal Treatment of Steel

In summary, it says that steel won't change much until around 480*C
"Stress relief heat treatment takes place at relatively low temperatures between 480°C and 680°C and results in removement of the workpiece's residual stress. This stress is produced by mechanical deformation or processing. Other than that, steel properties should not be changed. "

And the lowest temperature that produces changes in steel begin around 550*C.
"Recrystallization annealing is reestablishment of crystallite forms as the ones that existed before strain hardening. To do so, the work piece is heated to temperatures just above the temperature of recrystallization, usually between 550°C and 700°C. The temperature of recrystallization depends on material and level of deformation."
So you should be OK, except I have no actual experience in this area.
Here's another interesting page: steel identification, color, steel, identify, temperature

 

[MarsaGSX]

Thanks for the Help..

Actually just ordered new Eagles at MAP..Wasn´t 100% sure..

Venca

 

[gstryyder]

i stick with the rods you just purchased. WOULD NOT trust that rod you just heated up...