Rebuilding lower end, Rod bearings etc.

[J_Squared]

Hey all, figured I'd ask for some advice for re-doing rod bearings as I spun one last fall in my '91 GT and have just found the time to start working on the poor car. The idea seems simple enough, I just would rather only do this once and be on my way. Other than the normal torque specs and such, any tricks I should know about to make this go as smoothly as possible? Thanks.

 

[liljoe07]

Check the clearance between the Rod bearing and rod throw. This is critical. Use good assembly lube, and keep the rod caps with the rods they came from.

 

[lancec2c30]

Yeah. what ^ he said. throw down a piece of cardboard and mark down cylinders 1-8 on it with a sharpie. Once you pull each rod cap, put it on the sheet. Make sure you keep them all facing the correct direction. Just to make sure they don't get mixed up, draw a arrow facing the front of the engine on them all with the sharpie too.

Go buy some green plasi-gauge to check clearance on all the bearing when you go to put it all back together. Don't put assembly lube on the bearing until after you have gone through the process with the plasti-gauge.

Other than that, have a good torque wrench and take your time.

 

[doorvip]

how do you know when you spun a bearing?

 

[90lxcoupe]

how do you know when you spun a bearing?

Sudden loss of oil pressure, noises coming from the bottom end of the motor.

 

[J_Squared]

My hint was the massively loud clattering lower end. Which after removing the heads you can watch the number 2 piston not move for about a 10 degree turn of the crank pulley.

 

[old_blue]

basically the rod clatters around the crank since the bearing is no longer there. When I open my 383 stroker and grabbed the caps one by one the #7 wiggled back and forth like it was made to be free floating. really sucks when you are 10 miles from home and limp it back (I was young and didnt know). tore up the block pretty good too.

 

[J_Squared]

Update

So I feel like a scrub having said I spun a bearing a month or so ago... cause apparently my crank snapped after the 1/5 journal. And as always plans never go... as planned, just got the motor apart 2 weeks ago, and ordered the parts I'll need yesterday. Fortunately for me my cousin had a good crank from a motor he took out of a wrecked fox lying around. Hoping to get the damn thing running, if I'm lucky, Sunday. *crosses fingers* Seeing as it's been just over a year now since I last drove it.

 

[J_Squared]

Just want to verify what my researching has found for me as far as clearances. I have the plastigauges and am ready to roll. clearances of .002 - .003 for rod bearings and .0025-.003 for mains?

 

[liljoe07]

Looks good on the clearances.