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Texas Denny
07-23-2008, 10:26 AM
I pulled the engine from my wife's 50 Champion in December 2006. I put in new rings (bought from either Studebaker Intl or Newmann Altman). It took until November 2007 to complete body work and painting. Engine ran great until April this year (5 months - 6 or 8 car shows) when it started to burn oil. Initially it was annoying but after 6 weeks (maybe 80 miles), it was a cloud when accelerating - couldn't see the cars behind me. I estimate about 300 to 400 miles total on the rings. I pulled the engine apart again last night. The compression rings looked fine (compression measured OK). However, the oil rings did not stick out from the piston but they are loose in the groove - not stuck. They almost fall through the cylinder if they are square with the wall. Uncompressed diameter is 0.002" less than the cylinder diameter. I'm at a loss to figure out why this happened. The ends gap on the oil ring is about 0.015" in the cylinder so they aren't really wore out - just changed diameter and lost temper. I never over heated the engine. When I pulled it apart this time, there was no blow by.

Who do I buy rings from that will last more than 300 miles? I didn't keep receipts - no reason since no warranty and it ran perfect after rebuild.

DEEPNHOCK
07-23-2008, 10:51 AM
Danny,
What style of piston rings did you install?
P/N? Chrome? Cast?
How did you measure your piston ring end gap?
How much taper was there in the cylinder?
How much 'ridge' was there at the top of the cylinder?
What prep work did you do to the piston ring grooves before you installed the piston rings on the pistons?
What prep work did you do to the cylinder before you put the pistons and rings back in?
This info might help answer your questions.
Jeff[8D]

Texas Denny
07-23-2008, 11:09 AM
The supplier did not offer different styles. I used what they sent me. It is so long ago, I cannot recall any descriptions on the packing.

End gap is customarily measured by placing the ring inside the cylinder and measuring the end gap. Is there another way?

The cylinders were within spec up and down the cylinder. There may have been a 0.001 or 0.002 variation up and down but no more.

No ridge at top.

Honed the cylinders as I have on a couple dozen other rebuilds.

Ring grooves were thoroughly cleaned.

Thank for your reply.

Texas Denny
07-23-2008, 11:10 AM
One other thing. The compression rings appear to be fine.

DEEPNHOCK
07-23-2008, 11:19 AM
Originally posted by Texas Denny

The supplier did not offer different styles. I used what they sent me. It is so long ago, I cannot recall any descriptions on the packing.

End gap is customarily measured by placing the ring inside the cylinder and measuring the end gap. Is there another way?
Usually squared up and measured partway down the bore..
(Pushed down there with an upside down piston)
The cylinders were within spec up and down the cylinder.
There may have been a 0.001 or 0.002 variation up and down but no more.
.002 taper is great
No ridge at top.
Superb
Honed the cylinders as I have on a couple dozen other rebuilds.
What grit stone? Straight hone, or Dingo ball hone?
Ring grooves were thoroughly cleaned.
Scraped with a broken ring, or a ring groove cleaner?
Thank for your reply.

Were all of the ring 'gaps' rotated so they did not line up?
Wonder if the rings you were sold were chrome rings?
They are a tad harder to get seated.....
But your finding a weak oil ring is more telling.
You can't inundate the top rings and expect them to control massive oil flooding.
Hang in there... You'll find it!
Jeff

Dwain G.
07-23-2008, 11:50 AM
From the wording in your posts I get the impression you received one-piece oil rings, not the three piece style with an expander and two scrapers?

http://home.comcast.net/~jdwain/images/63.63.jpg
Dwain G.

Texas Denny
07-23-2008, 01:39 PM
Actually, the oil ring was four pieces. It had the typical side rings and a spacer to allow oil to be removed. But it had a waffle plate with small holes in it that fit under the other three. This waffle ring is the same width as the oil groove and it would decrease the ability of oil to drain. I thought about leaving it out as it didn't make much sense. But I assembled as instructed.

I know what happened - the oil ring lost temper and simply shrunk to the cylinder size. I need new rings but where do I get them? I need a reliable source for these rings - I don't want to do this three times.

54-61-62
07-23-2008, 07:18 PM
this is a common issue with many oil ring sets that are currently made. I went through this while putting rings in a 185 this last winter and have been told about it by several other people.

My suggestion, find a nos set of 1 piece old style oil rings. SASCO still sells these if you specifically ask for them.

Other suggestion is to carefully expand in inner expander of the 3 piece oil ring. David taught me this last winter. take the "inner expander" and put it around some round object that is close but a little larger then the piston diameter. take a pair of needle-nose pliars and carefully pull the ends of the expander together so in essance you are streching it so it has a larger diamater. It's hard to explain without pictures though.






quote:Originally posted by Texas Denny

Actually, the oil ring was four pieces. It had the typical side rings and a spacer to allow oil to be removed. But it had a waffle plate with small holes in it that fit under the other three. This waffle ring is the same width as the oil groove and it would decrease the ability of oil to drain. I thought about leaving it out as it didn't make much sense. But I assembled as instructed.

I know what happened - the oil ring lost temper and simply shrunk to the cylinder size. I need new rings but where do I get them? I need a reliable source for these rings - I don't want to do this three times.