Motor Rebuild 550E 16valve

[Anonymous]

Hi I'm rebuilding my 83 550es and I have a lower end with pistons I got off Ebay. My question is: the piston rings seem to be alittle stuck I can't spin them freely they are like slighly rusted in place. If I just put them in and rebuild the motor will they probaly break free then from heat and oil or will I be burning oil like mad.
Thanks

[shaftzuki]

You need to remove the rings, throw them away, clean the pistons and the grooves for the rings and install new rings ... If it's already apart, take the time to rebuild it the right way, you'll be glad you did!! 8)

[reem98]

Well I posted this about 6month ago
I put pistons from another bottom end in to my original sleeves. And yeah it ran like crap had like 130psi when I should have 130-199psi.
Can anyone tell me if I put my original pistons back in my original sleeves will that work, the motor ran fine before the prob was a bad rod bearin on the crank.
I only ran it with the other pistons and rings for like 2 hours of on time.
Please help me out with my mistake
Thanks

[reem98]

Please if anyone can give me some insight to my last post that would be awesome thanks

[jgordon]

I wouldn't. You need to pull it apart and clean all the grooves real well. Check the clearances and install a new set of rings. Check your wrist pins and make sure you gap the rings properly. Its a pain to pull it all down and not do the proper job and have to go through all that again (-;

[duaneage]

FIrst, remove the head and check the bores. you need a inside bore gauge to do this with. And a micrometer to read the bore gauge. If your not aware of what thee are this may be a bit beyond your expertise.

You have to check the bores to see what the size is currently. Top and bottom, side to side. in the Clymers or Haynes manual there are specifications that spell out what the maximum bore size can be before new pistons are needed.

If you need new pistons find another engine because it is not worth it to bore this little engine out and install larger slugs.

If your bores are all good then you can buy standard sized rings.

Next you have to hone the cylinders to achieve a nice crosshatch finish and remove the glaze from the walls. This will remove a small amount of metal, about .0005".

Each ring must be insderted straight in the bore and checked for gap distance. Set the ring about 1 inch down all around in the bore and check the opening of the ring gap. Compare to the clymers book reference and file the ring ends if it si too big until it is correct.

When you are done with all that ring the pistons and insert in the bores. Refer again to manuals for specifics..

You have to do these things the right way, engines are amazing how they work for so long but they have to be birthed properly.

[reem98]

thanks guys
I have one more question so far when they sell rings on like bike bandit is that for 4 cyl or just on cyl at a time per price.
Thanks

[jgordon]

thanks guys
I have one more question so far when they sell rings on like bike bandit is that for 4 cyl or just on cyl at a time per price.
Thanks

That is for one piston....Looks like about a hundred bucks for the four 8O

[duaneage]

At this point unless your planning to build a class racer cafe bike I would consider another engine or even another bike. Internal engine work on bikes can get real expensive and this assumes you go stock. Modifications cost even more and tuning can be a real Hillary to get just right.

If ALL you need are rings you looking at a 100.00 set of rings, 50 dollars worth of tools like cylinder hones, gauges, torque wrenchs, 70 dollars for a gasket set, and another 100.00 easily for incidentals like intake boot O rings, plugs, helicoils, chain tensioners, etc. And you do have four piston ring compressors for the small size pistons , right?

If you have the tools already and are experienced it might be worth it. But be realistic in where you will do the work and the tools needed. I have all the tools, I have done engines before, and a heated garaged to work in and would still not rebuild an engine because it is cheaper and easier to find another and swap it out.
It would be a shame to get into it just to find out that you spent more than another engine would cost.