I am 90% sure that Iv spun my 2nd cylinder bearing the other night. So i need to get in there. Yes I have searched but like everything in my life, when I look for it, I dont find it . Will the easiest way to DIY this to be removing the engine? Or is it possible to just remove sump etc. I have a hoist but havnt had time to get it up there, so I cant see how easy a sump removal is.
Second question, any suggestions of any parts to refurbish/replace while I have my engine apart. I might consider stripping the whole thing down if theres a big benefit to replacing anything special inside. Am I going to have to remove the head anyway?
Can anyone who has spun a bearing before give me any insight to how long they had the engine running to what kind of damage they recieved to crank, rods etc.
Cheers

 

When you spun a bearing, you also need to check the crank journal. If the crank journal is messed up, you don't have choice except to rebuild.
If the cylinder wall also messed up --- go rob a bank for labor & parts.

You can replace the bearing without taking the engine out but it's a half ass job.
Take the sump out and figure which bearing. If you find it, start picking the old bearing out by unbolting the piston rod bolt to the crank journal. Check the journal carefuly. If ok and just need an emery cloth to polish, then do so.
Push in the upper bearing with a small pick, then install the lower bearing. Put it back into torque spec. Clean the oil thoroughly including the oil cooler.
Try how long the new bearing will last. If spun again...then the bearing and the journal needs to be micro...maybe you need and oversized bearing.

 

So its actually ok to emry the crank journal?
Im certain its cylinder 2.
What are the odds of having a scored cylinder wall? Do people more often get away with just replacing bearings/polishing journals. Or is it more likely to have more extensive damage?

 

i can chime in on the engine removal...


pulling the engine and tranny together as one piece is a lil tough without damaging anything (scraping the tunnel wall and firewall). i have removed several s2000 engines by- dropping the whole subframe, using the hoist to pull it out through the top, and removing the transmisison from under the car and pulling the motor from the top.

out of the three ways i have done it i would say dropping the subframe is the easiest. but without access to a lift, it can be pretty troublesome. so my suggestion would be to remove the transmission from under the car then pull the motor from the top.


its pretty difficult to remove the engine and trans as a whole without damaging anything. if your anal like me i would suggest the other two methods.


good luck pm me if you need any help, i can suggest some short cuts to the process...

 

O yeh i'd def remove the trans from bottom first. Gotta install my new HD clutch and lightweight fly while im in there.

 

Yeah its ok to emery cloth if the damage is very minimal. Not enough tolerance to use oversized bearing by just using emery cloth.

Scored cylinder can happen. Remember the rod + piston is slapping due to bad bearing. The gap between the piston ring and the wall enough to score the wall.
Just like slapping unbalanced piston to the wall.

Did you keep using the car even though the bearing is bad?

 

Na I dont use my car. I dont quite understand, how does the rod bearing being spun create clearance inbetween the piston and cylinder? I thought the clearance would be between the rod and the crank, and the knocking is from the rod hitting the crank journal everytime power is fired down.

 

If the little end is bad it can let the piston twist, but I'm assuming you spun the big end.

 

You know how many cylinder wall I trash with my two stroke dirt bike?

When the rod is slapping with the journal, the piston keep twisting.

 

Yeh I wasnt contesting what you were saying, I was just asking to ellaborate how it affects the piston's clearance for my own knowledge.

I can certainly picture how it would affect it if it were the small end.
Can someone try explain to me how the piston 'twists' with the big end spun? Do you mean like more of a shock or vibration connects with the cyl wall from the piston causing a scoring?
I dont need a fully dumbed down explanation (Im a mechanical fitter) just summin a bit more then "the piston keep twisting"