Slappin' on some new rod bearings...yall....

[elementalwindx]

Had to say it "yall" Anyways, short story: got this built 7bolt that spun a rod bearing. I'm building a 6bolt to replace it.

#2 bearing screw'd, crank journal looks and feels fine to the fingernail. I still want to polish the journal and end caps to remove any fine grooves that might cause this to happen again. Any experienced/knowledgable techs want to tell me what kind of polish they think I should use and what do you think I should use to polish it with?


Also, odd ball question for you 2g 7bolt guys. When you remove the coil packs, have you been able to do it without loosening/removing the fuel rail? Its such a PITA.

 

[blcknspo0ln]

Had to say it "yall" Anyways, short story: got this built 7bolt that spun a rod bearing. I'm building a 6bolt to replace it.

#2 bearing screw'd, crank journal looks and feels fine to the fingernail. I still want to polish the journal and end caps to remove any fine grooves that might cause this to happen again. Any experienced/knowledgable techs want to tell me what kind of polish they think I should use and what do you think I should use to polish it with?


Also, odd ball question for you 2g 7bolt guys. When you remove the coil packs, have you been able to do it without loosening/removing the fuel rail? Its such a PITA.

can't answer the first question , but no.. i've never found a way to remove the coil pack withou removing the fuel rail.. besides, it only takes a couple minutes to take it off anyway

 

[jdmjason]

the question is why did that bearing spin?

 

[elementalwindx]

the question is why did that bearing spin?

Thats not what I'm asking. I already know why it spun. Oil pressure too low for the period of time my oil return line was f*ked. Stupid SBR. Long story, yadda yadda. Like I said lets stay on subject please.

 

[GSTinCO]

Had to say it "yall" Anyways, short story: got this built 7bolt that spun a rod bearing. I'm building a 6bolt to replace it.

#2 bearing screw'd, crank journal looks and feels fine to the fingernail. I still want to polish the journal and end caps to remove any fine grooves that might cause this to happen again. Any experienced/knowledgable techs want to tell me what kind of polish they think I should use and what do you think I should use to polish it with?


Also, odd ball question for you 2g 7bolt guys. When you remove the coil packs, have you been able to do it without loosening/removing the fuel rail? Its such a PITA.

I had a spun bearing as well and my dad (old school hotrodder) mentioned crokis (sp?) cloth. It is almost like SUPER FINE grit sandpaper, maybe more like a polishing cloth. You can tear a width the size of a rod journal and polish it up. I would make sure there is not material left on the crank to cause more problems first.

 

[elementalwindx]

I would make sure there is not material left on the crank to cause more problems first.

I double and tripple checked that, and when I go to put the new bearings on, I'll quad check it heh.

Where can I find this stuff you mention? Autozone? Advance Auto?

 

[pneumo]

I polished my crank with 1500 grit sandpaper. It can be found at some hardware stores, or in paint shops. Make sure you polish in the same direction as the rod spins on the crank.

 

[elementalwindx]

I polished my crank with 1500 grit sandpaper. It can be found at some hardware stores, or in paint shops. Make sure you polish in the same direction as the rod spins on the crank.

I know it sounds stupid but I have no idea which way the rod spins on the crank. Looking towards the passenger side of the motor from the driver side wheel, is it clock wise or counter-clock wise?

When you say you polished it with 1500 grit, do you mean you wet sanded it, or you used something like mothers mag/aluminum polish on the 1500grit paper? or you dry sanded it with the 1500 and whiped it off with a cloth?

 

[bullettdsm]

I polished my crank with 1500 grit sandpaper. It can be found at some hardware stores, or in paint shops. Make sure you polish in the same direction as the rod spins on the crank.

I just did my rod bearings only (1200 miles so far). Had low oil and brought it up to 8k and it spun. I used wet sand 1200 emery. 1500 would be fine. I think pneumo meant to say that you do not go side to side. Rip off a piece that fits inside the journal area and go around.
MB

 

[pneumo]

Thanks for asking, I meant that I dry sanded it with 1500 grit sandpaper. You also reminded me of another step to do before you start sanding (I hope it's not too late); drag the sandpaper across the edge of a metal bar of some sort a few times before you use it on the crank. This will knock down the sharpest stones in the sandpaper so it doesn't cut sharp edges in the crank. Once you start using it on the crank it won't feel like it's doing anything, but that's good! The idea is to take off the tops of any ridges in the bearing surface, not to dig in and remove material. This method won't do anything for ridges in the crank that are deep enough to catch a fingernail, it's only for good cranks that need to be made better.

So far the motor I built this way has made about 450 HP and sees 25psi of boost regularly

 

[ltho98]

I personally would just pay the 20 bucks to get the crank polished, 7 bucks per rod to recondition the rods and 30 to get it clearanced AT A REPUTABLE MACHINE SHOP.

The amount of error involved with polishing your own crank or reconditioning your own rods is rather high as I come to learn the hard way.

... and yes. I did exactly what these guys were recommending too.

 

[elementalwindx]

Well I finished it up and it runs great.

Ltho how long did yours last?

Also I found out the #4 was about to spin too.

 

[ltho98]

Mine lasted roughly about 1200 miles.

But it failed at the drag strip I was doing a 1/4 mi run and it just happened all the sudden.

Oh yeah, another result was that it also shot bearing material into my RS49 and killed it.

Thank you Ben, Kevin, and Bach for warrantying that thing.