[2Tomato]

This topic is a spawn of Wingwalker's thread entitled Another Budget Rebuild.
It is obvioius to me now that I have a lot to learn about proper care for motors, their rings, and other internal components. Like Wingwalker, I am looking for seasoned advice/wisdom/knowledge on this topic, as I may have been educated improperly here on the farm.

As I don't wish to high jack Wingwalker's thread, I am curious about break-in procedure for high compression pistons in a rebuilt motor, as I am considering that option for a motor rebuild in the future. Are there any break-in procedure differences between lowand high compression engines??

Would anyone like to add to 60sRacer's excellent advice on proper break-in technique? (even though thisadvice is plenty of work as it is..)

I prefer a fairly closed area for initial break-in. The reason is that you will be accelerating and slowing/stopping repeatedly for a while. This will drive anyone behind you nuts, and could risk an accident. A big industrial park on a Sunday works well (unless the local clubs are having an AX), or a good back-country road where you know traffic is very light; choose a place with straights and sweeping turns that can handle 30 - 45 mph.

Most of the time I've had a new engine, I also have new brake pads. The two go well together for break-in. To seat your pads well, you need to accelerate to about 45 mph, and brake firmly to a full stop, release and repeat, taking a minute while moving at speed to cool the discs. I like to accelerate quickly but not full throttle. Make your last few stops at 100% - but not sliding the wheels - to check-out front/rear balance. I use an adjustable Tilton valve in the rear brake line, so it's a good time to fiddle with it's setting.

After a half-hour, the brakes should be working really well. Meanwhile the engine loading is starting a good break-in cycle, and the suspension and other bits are exercising their range of motion. Vigorous driving with big fast turns, but nothing above 50-60%; enough load that everything gets to settle in, but no where near breaking anything that might be loose. Time to stop and fully inspect all the mechanicals for leaks, loose bits, etc. I try to make a check list of anything that had a wrench or screwdriver on it.

Of course, you stop immediately for anything unexpected, even a little noise. They are hard to find, but easier to fix than if you wait for something to break!

By now you've done maybe 20 - 30 miles. Go home and fix all the little bits you found. Now that the pads are seated, bleed the brakes again. I use a pressure bleeder by Motive; I've tried everything, and never get a really solid brake feeling without it. If I have ANY reason to worry, I'll drain the oil just to check the magnetic plug for bits. Buy oil by the case - Alfas use 8-9 quarts for a change anyway.

Phase two is OK for good road driving. Increase vigor so that at about 100 miles you are driving 100%. A track is super for this phase if you have access. Go home before you get to 150 miles. Inspect everything again. Fix it again. If you didn't change oil before, do it now. Same for TX or Dif if those were renewed (they got new fluids anyway didn't they?). Check alignment.

Finally, go for a long all-day drive on a good Alfa road. Come home before you get to 500 miles, but not a lot before. Be vigorous! Refill the gas tank half way, and inspect everything again while your there. Check tire pressures too. Now go home fiercely, but lighten up for the last 10 miles.

At home, change to your running oil (you were using a good break-in oil weren't you?) and replace all the fluids - brakes too - if they haven't already been.

You should have a car the will thrill you for years.

Robert

 

[papajam]

I'd bet that if you ask 10 different people on how to break in an engine, you'd get 10 different methods. Each builder will usually develop a technique that works for them and they stick with it. I generally use the break in method recommended by Alfa for all makes of engines I build. But each engine has it's own unique feel to it so each engine is broken in a bit differently. It can't be described, only felt and heard.
Do a bunch of reading. Learn about different methods, pick one or combine elements of a few and go with it. Just don't attempt any land speed records till there's some miles on it (AMHIK).

 

[kcabpilot]

It's one of the most over-thought and over-discussed issues out there. Obviously there's more than one way to skin a cat and it really boils down to just a couple of things you SHOULDN'T do. Don't baby it and don't spend an inordinate amount of time idling and free revving while trying to get fuel and ignition stuff perfectly dialed in before actually driving it. Take it out and get the rings seated. In fact, you don't really even need to use break-in oil as it's just a little 2 liter motor with a 7 quart oil capacity and a full flow filter. There's just not going to be that much material in suspension to worry about, the rings are going to be seated pretty quickly if you follow the procedures. Being a water cooled engine, there's very little concern about temperatures providing all is proper.

The main thing is keep an eye on everything, look for leaks, things coming loose or things that may not have gotten tightened to begin with.

There are no differences due to high compression pistons other than you may want to verify your piston to valve clearances with a piece of solder prior to first run, especially if your head height dimension is near minimums.

 

[Richard2]

Ring manufacturers have posted on their web sites recommended break in procedures. Just another place to look. I like the Hastings method for Hastings rings.

 

[Alfar7]

Break in proceedure

Most current engine shops, as well as cam builders suggest running the engine unstopped, and no rev changes (unloaded ) for 20 minutes to 30 minutes, at 2000-2500 RPM to properly break in cams and followers as well as rings and bearings. After that hot retorque to 5 lb over head torque speck (hot) and exhaust and intake nuts.
This means driveline and all systems must be ready to run with fan on radiator to force air over radiator.

A 40 wt non detergent oil with 1 bottle of ZDDP is the correct lube to break in with.( I use Travelers 40 wt available at Tractor Supply for $30.00 or less for 2 gal container.

As well break in period should be done with water only, (no antifreeze) and I use one tube of powder type leak sealant, not Bars Leak. After the retorque the water can be drained and antifreeze added.
Drive the car about 500 miles as you normally would and change oil and filter. Synthetics are really ok with ZDDP added, but never use any of them with viscosity less than 20-50 are you will have cam / follower issues if running any non stock cam, or higher spring rate performance springs. I prefer Valvoline to other synthetics including "Boutique" brands.