Cleaning Cylinder Before Assembly

Stephen Hill

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Can somebody please explain why it is necessary to wash the cylinder bores in hot soapy water prior to assembly?
What's wrong with a thorough scrubbing with solvent?
Is soap and water actually better?
Water produces flash rusting which is hard to avoid and kind of annoying.
Or maybe using water is some kind of rirual that we can't let go of. Like baptism in the River Jordan.
What's the real reason?
 
Stephen Hill said:
Can somebody please explain why it is necessary to wash the cylinder bores in hot soapy water prior to assembly?
What's wrong with a thorough scrubbing with solvent?
Is soap and water actually better?
Water produces flash rusting which is hard to avoid and kind of annoying.
Or maybe using water is some kind of rirual that we can't let go of. Like baptism in the River Jordan.
What's the real reason?
Click to expand...
To dissolve the oil film holding the abrasives left from the stones.
Have WD-40 there as you work, spray while still wet from rinsing.
 
Stephen Hill said:
Can somebody please explain why it is necessary to wash the cylinder bores in hot soapy water prior to assembly?
What's wrong with a thorough scrubbing with solvent?
Is soap and water actually better?
Water produces flash rusting which is hard to avoid and kind of annoying.
Or maybe using water is some kind of rirual that we can't let go of. Like baptism in the River Jordan.
What's the real reason?
Click to expand...
Here is a quick guide. Its the same procedure as we do as well.

https://throttle.news/blog/2020/10/19/how-to-use-total-seal-quick-seat-assembly-lube/
 
No soap and water in that video.

Re: the comment: "To dissolve the oil film holding the abrasives left from the stones."
I would have thought that solvent would do a better job of dissolving an oil film than soap and water.
 
Stephen Hill said:
Can somebody please explain why it is necessary to wash the cylinder bores in hot soapy water prior to assembly?
What's wrong with a thorough scrubbing with solvent?
Is soap and water actually better?
Water produces flash rusting which is hard to avoid and kind of annoying.
Or maybe using water is some kind of rirual that we can't let go of. Like baptism in the River Jordan.
What's the real reason?
Click to expand...
If you want to avoid flash rusting , do all the scrubbing etc and rinse , then spray with WD 40 then blow dry .I also like to use a small brush to help get the grit from the pores of the cross hatch, do it as many times as it takes to get it clean .
 
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Stephen Hill said:
No soap and water in that video.

Re: the comment: "To dissolve the oil film holding the abrasives left from the stones."
I would have thought that solvent would do a better job of dissolving an oil film than soap and water.
Click to expand...
You can use Dawn or another degreaser like purple(not green) simple green but finish with wd-40 to prevent flash if you would like.
 
Stephen Hill said:
No soap and water in that video.

Re: the comment: "To dissolve the oil film holding the abrasives left from the stones."
I would have thought that solvent would do a better job of dissolving an oil film than soap and water.
Click to expand...
The bubbles/suds of the detergent do better at suspending the debris and thus carrying it away when rinsing.
 
Once you think you have got the bores clean with either solvent or hot soapy water, wipe them with paper kitchen hand towels and check the paper for cleanliness . You will be surprised by the results !!!!
A good way to see how clean(or not) they are.
 
I use washing up liquid hot water and a scourer
I scrub the hell out of a new bore every which way to get rid of all micro abrasives out of the crosshatching
I use running in oil I zero smoke and extremely low oil usage
One thing I can't bring myself to do is start a freshly bored engine with a dry bore
 
Don't forget the tappet tunnels. I use a fairly stiff 1" bottle brush for them. I do at least three wash rinse cycles. Then dry all bare metal with paper towels sprayed with WD40 (WD = Water Displacement). No rust. Then blow the rest dry. Also, if painting, that's done before the final cleanup.
 
baz said:
I use washing up liquid hot water and a scourer
I scrub the hell out of a new bore every which way to get rid of all micro abrasives out of the crosshatching
I use running in oil I zero smoke and extremely low oil usage
One thing I can't bring myself to do is start a freshly bored engine with a dry bore
Click to expand...
Yes , I remember older talk of starting up a new bored engine using no oil on the rings . Lept back a tad in disbelief .
I've always used paper towels or even better , blue shop towels , soaked in oil , to clean the newly machine shop bore to match the oversize pistons to fit . Marked left and right with blue machinist's dye of course . When I feel that the bores are cleaned then fresh oil to the bores ( again ) and fresh oil to the piston rings , then compressors fitted and good to drop into place .
 
Torontonian said:
Yes , I remember older talk of starting up a new bored engine using no oil on the rings . Lept back a tad in disbelief .
Click to expand...
That is my preferred method, dry bore with one drop of oil on the front and back face of the piston well below the rings, never had a ring bedding in or piston problem. Once the oil gets to the big end it will be splashing up onto the bore so the rings only get a few cycles of dry running but its enough to start the bedding in process.
 
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A simple test - after honing, clean with whatever solvent and when "clean" wipe with a white cloth. There will be grey/black deposits on the rag. Soap and water cleaning will eliminate that.

As noted, you can wipe the bore with WD40 to prevent rust until you install the pistons. Whether you install the pistons dry or lubricated is your choice. Two performance-engine building shops I was associated with some years ago install them dry. Other shops do anything from dunking the piston into a container of oil just prior to assembly to placing some oil on the rings. Another one puts only a smear of oil on the thrust side of the piston skirt/none on the rings/bore. Go figure...
 
I just ordered a set of rings from CBS and they recommended setting the rings dry.This was all new to me but I am not an engine builder. The last time I installed a set of new pistons and rings I coated all the rings with oil and staggered the end gaps,etc.Appreciate all the advice from people who know much more than me with the error of my ways.
Mike
 
Unless you are using break in oils then modern oils are too slippy for a fast break in so it can be a bit hit and miss. Combine that with the coarse grit hone for cast iron rings now being hardly used you could also end up with too fine honing. A dry fit at least gives you a chance to get the break in started and some pressure behind the rings to get past these issues. Been doing it for 20 years including on a 5 cylinder Audi Diesel engine that went on to do 230,000 miles.
 
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