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Discussion Starter #1
Well, My new liners are in. I wound up just cleaning up the block liner mating surfaces real good and putting the new liners with the O-rings provided in my engine gasket set from Centerline without any sealant. I noticed the O-rings in my gasket set were slightly smaller diameter (around the liner, not cross section) than the ones provided on the liner set, so they fit a little tighter on the liner.

I have several questions now about the piston/rings. I have read on several threads, and centerline recommends replacing the rings provided with the liner set with hastings rings. My question is how important is it to replace the rings which come with the liner set. I have the 10.4:1 set, and I haven't ordered any additional rings. I was going to assemble the pistons tonight, but If I need to replace the rings, that delays everything by a week or so. Also, I hate to throw away brand new rings and spend another $100 on top of the $500 spent on the new liner set, but I don't want to have to do this again any time soon, I want it right. Has anyone used the standard rings which come with the liners/piston set ( I think its Borgo), and how well do they break in and hold up over time. My second question is on assembly what do you lube the piston/liners with (std motor oil?). Does it make any difference in break in what oil is used to lube the liners and pistons when assembling the engine? I have 20-50 castrol, is that ok.

John R
 

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You will get lots of different opinions on this one. Here is mine:

The standard Borgo rings are exceptional quality. One would think that the manufacturer of the pistons and liners would be able to get it right after making them, how many years???? The liners in Alfas are quite different to the bores in many ordinary engines with cast iron blocks in that the iron much harder. My feeling is that the manufacturer of the piston/liner would know best.

I have pulled down Alfa engines with + 350,000 km on them. The engines still had reasonable compression and were not consuming huge amounts of oil, but the top rings were worn completely through the chrome facing!

My opinion for the recomendation on hastings rings could be consistency in break in. I think the Borgo rings require higher combustion pressures to bed the rings in (read harder driving). Most people are reluctant to give a brand new engine a bit of stick and end up not bedding the rings in properly. Hence the recommendation of softer rings: less chance of smokey engines!

I would recommend a quick bottlebrush hone be used prior assembly, use non-synthetic 20W-50 oil (for assembly and running in) and ensure that you do not allow the engine to idle for a long period after start-up. I like to give it some wide open throttle (WOT) rev-ups during the initial tune to get some real pressure in behind the rings. When initial adjustments are made and engine warm, take her for a spin. During the first 50 km, lots of WOT up to 4000 rpm through the gears. Don't be scared, if you built the engine right, you should be able to rev it all the way to the redline straight out of the shed.
 

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One more quick tip: Visually inspect the liners very carefully. Over the years I have found a quite a few liners that still have the machine marks in the honed bore surface. At a casual glance this is not immediately apparent. This will cause incureable oil consumption.
 

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Discussion Starter #4
Thanks for the feedback. After talking to a guy at centerline, I went and put the pistons in last night with the supplied Borgo rings. I found a thread which recommended washing out the liners with soap and water, than after drying, using Marvel Mystrey Oil (much thinner oil) for piston and liner lubricant to aid break in. So that is what I did. I haven't put the head on yet, so I will inspect the liners hone marks carefully tonight with a bright light to look for machine marks. I do plan on no synthetic 20-50 oil for run-in. I also plan on running it hard (up to about 4k rpm) for break-in both acceleration and engine breaking. I'll let you all know how it turns out.

John R
 

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Discussion Starter #6
Break in went great! No smoking and oil consuption is low. I have about 1500miles on her now and am ready for oil change again. Only problem is nagging oil leak. Not sure where it is coming from, but there is always a puddle on the garage floor. It's been that way forever it seems.

John
 
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