how to choose the right bearing for rebuild

[suprana1990]

hi everyone

i am rebuilldiing my engine and would like to know how to get the correct bearing.

i don't think i am getting any machining done on the crank, i would like to put new bearings in and new bearings for the connecting rods and put everything back together.

i will be mic'ing all crank and connecting rod journals for correct measurement
any input on how to choose the bearing would be great.

 

[Supraboostin]

if you dont have experience on this i would suggest you to take it to a machine shop

 

[TONY!]

Yeah, it can be a tricky thing to build one of these motors as Supraboostin just mentioned.

I always thought that the ideal clearance for the crank was .0015"
That is what machine shops aim for. I will find that info for you later in full

Many people use the Toyota ones because they are the most precise under some applications. You can order those right here from Champion Toyota:
http://supramania.com/forums/forumdisplay.php?f=74

Clevite77 bearings are also very well regarded.

More info on rebuilding:
http://supramania.com/forums/showthread.php?t=276

 

[malloynx]

if your asking these questions; seek help from a machine shop. the 7m is not a motor to learn on, the specs have to be dead on.

 

[TONY!]

if your asking these questions; seek help from a machine shop. the 7m is not a motor to learn on, the specs have to be dead on.

I thought that was the purpose of this forum: to learn.
If not, why should we be here? I think with enough research suprana1990 could accomplish his goals.
We don't really know if suprana1990 is building his first motor neither.
I don't know him; do you guys?

Information I give you may be true, but not enough to get the whole job done -- it is only a supplement. Same with the thread I gave you (the link).

I was never trained to paint by a school; I learned on my own, and right from the start I was out for show quality work. The following is the first machine I painted. So many people said what I wanted to do was not possible, or the ways I would do it. All of them were proven wrong and schooled in the process.

http://img.photobucket.com/albums/v519/Tony9RR/71.jpg
http://img.photobucket.com/albums/v519/Tony9RR/72.jpg

Glass like finish up close as it as all over the bike:
http://img.photobucket.com/albums/v519/Tony9RR/Blackk.jpg

Second helmet I painted, no wet sanding or polishing on the final finish -- that finish is out of the gun. Although I did clear to cover the paint edges, sanded the helmet thus getting the height consistent, then a final clear, and done.

http://img.photobucket.com/albums/v519/Tony9RR/avatar.jpg

Sorry to be so “look at this!” but it does make my point quite well: only he will know if he can do it and only he knows what he knows.

 

[TONY!]

...I will find that info for you later in full...

promised:

Clevites are available in stock, .025 over, .050 over .075 over and .100 over.
To get the right ones, you will need to get your crank mic'd and see what standard diameter it will clear to. At the very least you need .025 overunless you are dealing with a PERFECT crank.
The proper procedure is to mic the crank, order the appropriate bearings. Then DO NOT TOUCH THE CRANK.
Install the bearings in the rods and mains. Measure the inner bore diameter with the bearings installed, and cut the crank 1.5 thous smaller than that diameter.
Any reputable machine shop can get you clevites. My last set with .025 over mains, .050 over rods, factory thrust washers was $115.

Saved that thread for myself before the hack Glad I got a good thread to post it on.

 

[siman]

I let my machine shop do the measuring.....they have all the tools and years of experiance that I dont have...though i do know how to measure for bearings...I just didnt want to find out I measured wrong on my ( as of right now) daily driver.


Go to your local machine shop and have them measure and order the correct bearings for you...

though the best route to go is the STOCK route....the stock sized bearings if your crank and rods are in tolerance. Thank God mine were!


much luck,

Jonathan

 

[suprana1990]

thank you all for responding

one thing about NYC is i can't find a reliable shop around me cause one my car will be apart and no other vehicle to take the parts the machine shop, two i don't know any machine shop around me that i could rely on.

i am keeping everything stock, just want to have something to drive and go places.
this is a Jdm motor i purchase and took apart the whole thing(not replacing anything but gasket... bear with me i am a newb). The thing ran great for 5 months and the day of summer vacation my car decided she need to fix.

I lost all power, i give gas and it won't move until over 3rpm and the engine shakes.
i have to run a compression test, leak down.

i ask is because knowing that i don't have any machine shop to go to i figure i could get the standard bearing(which ever one that is, will hopefully find it when i get all the measurements) and put everything back.

i will be running some test tomorrow morning and ripping out the motor prob. by tues.
will try and keep everyone posted on how things go and i greatly appreciate the knowledge.

 

[TONY!]

I let my machine shop do the measuring.....they have all the tools and years of experiance that I dont have...though i do know how to measure for bearings...


Go to your local machine shop and have them measure and order the correct bearings for you...

though the best route to go is the STOCK route....the stock sized bearings if your crank and rods are in tolerance...

Since you mentioned that, here is a post on mic's and my thoughts on measuring:
http://supramania.com/forums/showthread.php?t=3177&highlight=mic*
(see post two)

Btw, I should put this in the Tech Section because it has good tech info.
Thread moved.