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Werner 05-14-2020 04:14 PM

How to mount the piston rings from above?
 

1 Attachment(s)
Hallo und guten Abend,

today when I installing the pistons, the lower oil drainage rings were extremely difficult to thread into the cylinder from above. Even with the help of a piston ring tension band it was not manageable. (Unfortunately, a part of the oil drainage broke off on the 4th cylinder.)

What am I doing wrong?

https://www.fordbarn.com/forum/data:...AAAElFTkSuQmCC

Patrick L. 05-14-2020 05:13 PM

Re: How to mount the piston rings from above?
 

First, gap the rings.
Install on the pistons
Stagger the ring ends
Use a compressor [ or cone] and tap the piston into the cylinder [ make sure clearance is correct]

JoeCB 05-14-2020 06:09 PM

Re: How to mount the piston rings from above?
 

That is a very strange looking oil control ring. Was that the entire ring ? I have seen spring like parts similar to the pictured part that is only the expander in a three piece oil control ring assembly. I am familiar with the three piece assemblies having a spring expander and two thin scraper rings.

Joe B

bbrocksr 05-14-2020 10:44 PM

Re: How to mount the piston rings from above?
 

That is just the expander or spring portion of the oil ring assembly.
It works with two steel rails, The gaps must be staggered and the ends of the expander must butt and not overlap or it will cause breakage as you have experienced.
Bill

Patrick L. 05-15-2020 06:33 AM

Re: How to mount the piston rings from above?
 

Ooopps, I mis-read the OP.

Gap the rings

Install rings from bottom first/up on pistons. In other words oil ring first. Most oil rings don't need an expander, the others can be put on without an expander but an expander does help.

rotorwrench 05-15-2020 08:24 AM

Re: How to mount the piston rings from above?
 

I'm not sure what brand those are. I prefer Hastings piston rings since they can be compressed a bit easier on the oil scraper ring assembly. It can be a challenge at times to compress them. It is possible that the expander ring size was incorrect but they do have to be tight in the bore or the ring will fail to control the oil movement from the cylinder wall. Follow the ring manufacturer's instructions closely when installing the set. Not all ring brands are installed the same way. If there is a problem, I try to contact the vendor who sells them and see what they say that might help since they will be the one to warranty them if they will not fit correctly. I learned the hard way not to try and trim them down so I would always recommend for a person to get more information before doing that.

katy 05-15-2020 10:04 AM

Re: How to mount the piston rings from above?
 

Quote:

Originally Posted by Patrick L. (Post 1887616)
First, gap the rings.
Install on the pistons
Stagger the ring ends
Use a compressor [ or cone] and tap the piston into the cylinder [ make sure clearance is correct]

Also: oil the rings before putting on the ring compressor and oil the cylinder before installing the pistons.

Jim Brierley 05-15-2020 11:37 AM

Re: How to mount the piston rings from above?
 

Also the top of the cylinder must have a slight bevel. If it is not there you can put one in place by using a large half-round, fine-cut file. This should have been done when the engine was bored, done by the boring bar.

MikeK 05-15-2020 02:04 PM

Re: How to mount the piston rings from above?
 

Following up on Jim Brierley's post about the top bore bevel, there is another problem:

Often the bore bevel or chamfer's depth exceeds the thickness of the thin top and bottom parts of that three-piece oil ring assembly. When you tap the piston down through your ring compressor those thin top and bottom sections are freed from the compressor at deck level and expand way up at the top of the bore chamfer. Now you're stuck.

I have experienced this quite a few times and my 'fix' was to take a waffled compressor (not the flat band type) and grind the band so the edge of the waffle is 45 degrees and sharp, not the original 90 which made it sit flat on the deck. With that 45 degree edge the compressor seats on the inside edge of the bore chamfer, below deck and permits those thin sections to pass easier.

40 Deluxe 05-15-2020 02:46 PM

Re: How to mount the piston rings from above?
 

What helps me when using a band type ring compressor with the two 'straps' is to put the lower 'strap' right over the oil ring, tighten the band, then lightly tap on the strap to encourage the rails to compress fully, and etighten. Then be sure to hold the ring compressor firmly against the block while tapping the piston in.

Werner 05-15-2020 03:21 PM

Re: How to mount the piston rings from above?
 

Guten Abend!

Thanks for all the advices. I have now ordered the .6 Hastings piston ring sets by Bratton's parts.

I think that attaching an angular chamfer to the top of the engine block places an extreme strain on the head gasket because the combustion pressure creates mechanical and hot contact surfaces

Good idea by knocking on the tensioning belt and tighten again.

What is a please is a "waffled compressor"?

MikeK 05-15-2020 03:34 PM

Re: How to mount the piston rings from above?
 

Quote:

Originally Posted by Werner (Post 1887949)
What is a please is a "waffled compressor"?

It looks like this:
https://www.fordbarn.com/forum/pictu...ictureid=42761

Werner 05-15-2020 04:17 PM

Re: How to mount the piston rings from above?
 

Yes, thank you, Mike. It's a piston ring plier. We call that "Zange".

Werner 05-19-2020 06:04 AM

Re: How to mount the piston rings from above?
 

3 Attachment(s)
Guten Tag.

The new rings arrived yesterday. Hastings look different than the previously assembled ones.

The second pressure ring had a lower nose on the outside for additional wiping off of the oil. This is not the case with the new ones, they have only a chamfer at the bottom and inside.

In addition, this wafer-thin steel shaft was under the ring. The Hastings didn't have this corrugated ring, so I didn't reassemble the old ones.

The scraper rings are also designed differently. At least not so fragile. The assembly of the oil control rings was very difficult with a lot of time over two hours.


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