I am currently in the process of slowly putting my engine back together. It is a slow process as i can only work on it when i go home between breaks in my college schedule. Heres my problem.
When i disassembeled the engine, i removed the pistons and rods. The babbit looks good so im hoping to reuse it. I marked the caps pistons and rods so i know what goes where. But today i disassembeled the caps from the rods and the rods from the pistons... I didnt pay attention to how they were oriented to eachother.. Is this a problem? (please say no)
Also, i was cleaning everything up and i have some nasty deposits on the underside of the pistons under the wrist pin. Any tricks for getting that gunk out? I took a wooden dowl and scraped down in there with a little gas and i could only get perhaps half of the gunk out.
Thanks for your time,
Big problem. I don't know how you can recover from that, except to carefully assemble each rod and figure out which cap went where by trial and error. There should be shim stock between each end of each rod cap if there is any remaining adjustment.
Nathan -- If you're not turning the crank and doing new babbit, the rods and caps need to go back the way they were. If you know which rod goes in which hole, the wrist pin bolt goes toward the cam. Maybe you can tell by bolting the caps on which way they were by the feel of them.
If the last guy who worked on your engine was on the ball, he would have marked each rod and cap using a file to cut notches or a center punch to make 1, 2, 3, and 4 marks on each part. Look for those; maybe you'll get lucky.
As for the gunk on the pistons, you might take them to an engine rebuilding shop and have them hot-tank them.
I just finished cleaning up a set of cast iron pistons.I media blasted them on the inside and while you can't quite get it all,I got most of it.
You can check each rod and cap using Prussian blue when you assemble the rod and cap on the crank shaft and rotate it full turn. If you get a full bearing then you have the correct combination. On rod 1 you have 8 choices, fewer
choices on rods 2, 3, and 4. It will take some work but you can figure out what is correct.
Once you have made your best guess of pairing the rods and caps the right way, assemble them on the crankshaft and use plastigage to test them. If the caps are oriented the right way, you will have even squish along the journal. If you have the cap turned around, you will get a big variation in the squish. It might take a little time but you can get things right. Not a problem.
Im sorry. I wrote this question poorly. i have 4 boxes. all of which have a cap, a rod, a bolt, a pin and a piston. So i know what piston, cap, rod, bolt, and pin goes in which cylinder. However. I didnt pay attention when i took the caps off the rod and the rod off the cylinder as to how they were oriented to eachother. So my question is, i know i will put the right cap on the right rod on in the right cylinder, but what happens if that cap is 180 degrees off where it was? what happens if i put the piston back on the rod 180 degrees from where it was?
I think Ted's answer answers this question mostly. also, I am the guy working on my engine haha all i can say is this is my first time
also, i think Richards response helps out too. Thanks guys! If others have anything to add, please do!
So you now have a 50/50 chance of getting it right.
Either Prussian blue or plastigage as mentioned above.
You can save yourself a lot of time and standing on your head if you can get your hands on a short piece of 1 1/4" shaft.
It's not likely that more than one cap will fit properly with the bolt holes perfectly lined up.
just about none of these motors have never been apart before and usually the previous mechanic marked them some where ! really look em over, no chisel marks on the side, punch marks on top, somthing!1 stuff is quite often marked for front, or cam side for reassembly.
There are only two ways to orient the rod and cap. Most likely they will fit the shaft one way and bind up the other way. You can recover from this with a little time spent trying things out. Once you determine which way works, usually they can be installed on the shaft either way. Originally, the wrist pin clamp was on the camshaft side. Also, a little inspection will help on each bearing. If you look closely, scratches and wear patterns will line up one way and not the other. Also, if they are backwards the thrust faces will not be flush with each other. If there are shims involved with the bearings, use an equal amount on each side when you try them out. You'll get it.
Couple last points. The rods should all point the same way re the placement of the wrist pin bolt. I place my rods so the bolt is on the camshaft side. Try that first and see how the plastigage or Prussian blue works. If it looks like the rod Babbitt doesn't line up with the crank journal, then turn the rod so the wrist pin bolt is away from the crank. They all should point in the same direction.
The pistons may be the most difficult to get oriented. If they have a vertical slit, put the slit away from the camshaft if memory serves. If no slit, get creative. Eg look for numbers on the top of the pistons to orient them, look for wear marks that match patterns, if any, in the cylinders, see how the piston fits easiest within the cylinder without the rings, etc.
Its not rocket science, mostly thinking it through.