GT380J piston ring installation

[jhood]

I am working on restoring a 1972 GT380J and I am having issues with the pistion rings. I have cleaned the pistions and ring grooves very well. Upon installation, the bottom ring fits just fine, however the top ring is very tight and does not seem to want to completely compress together. Anyone have any ideas or insight for me? I know the top groove is slightly narrower than the bottom groove and all 6 of the rings measure about 1.46mm. Short of using a ring compressor I not sure if I'm missing something here. Any ideas would be greatly appreciated.

Thanks,
John

[TLRam1]

I may have ran into this, can't remember I would have to search for an old posts on here. At the moment I am too tied up.

[Craig380]

+1 on the above. Look for the small letter 'n' stamped on the ring near one of the ends ... that must face upward towards the piston crown.

[jhood]

Thanks for the quick replies.

I am lining up the ring ends with the piston groove, both top and botton. The rings are installed with the letters 'RU' both in the up position and the grooves have been cleaned with emory cloth.

I guess I need to try a ring compressor still as I am only having a problem with the top ring.

Any more insight for me is appreciated. Thanks.

[TLRam1]

Yes, I had the same issue, I did not re-read the thread but I think there was a different number for the rings that worked, my memory is shot these days. I may have other rings at my house that may or may not work.

Read this thread and see if the answer is within, I can look through my info on the computer if need be.

viewtopic.php?f=9&t=343&hilit=+GT380" onclick="window.open(this.href);return false;

[jhood]

You have solved my problem. Thanks a bunch. Now I can press forward with my restoration.

Apparently the ring set for the '72 380J is different from the '73 and after models. I took the set that I had and tried all of them in the top groove and none of them worked. I found another set that I had and it worked just fine.

Thanks again.