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Discussion Starter #1
A rebuilt motor requires you to adjust the valves after the first warm/cool cycle. Then again after the first drive or two (or seated the piston rings). Then again after 500-600 miles. Finally, you can adjust the valves one last time between 1000-1500 miles. It shouldn't need adjustment again until the normal service interval. That would be the *correct* way to do it. However, some people only do three valve adjustment intervals.

Here is what you should do. Go look in our FREE ONLINE SERVICE MANUAL located in our FAQ STICKY for the valve lash adjustment procedure. It's a full on service manual that is meant for this specific car, not a general manual that covers 3-4 different cars like Chiltons. Print those pages out, staple them, and write your car/year/model/name on the front. Take them to the mechanic and tell him that is exactly what you want him to do.

If you are concerned that they are not equipped, buy feeler gauges. They are a dime a dozen so don't worry about the price much. Also, here is the proper break-in procedure for a freshly rebuilt engine:

1 ) Start car for the first time and let it idle between 1300 and 2400 RPMs, constantly changing the idle speed. Have a spotter watch for leaks. Once it's warmed up and the radiator fans come on, shut it off. Do not drive the car yet.

2 ) Change the oil and filter immediately before the bearing, ring, and other particles in the oil have a chance to settle in places. Only use conventional oil. Cheap oil and filter is fine for it as long as it's the right weight oil (likely 5W-30). Do not start the engine yet.

3 ) After the engine has cooled for many hours without being started, you can perform the valve lash adjustment procedure. Some people like to re-torque the head bolts but it is not absolutely necessary on this engine.

4 ) Check all fluid levels and you can start the car. Let it idle for a minimum of 15 minutes, periodically revving it to 2000 RPMs or so. Never let it idle down for more than 45-60 seconds (it's bad for the new bearings and rings). Watch for leaks. Don't shut the engine off yet unless it has a problem.

5 ) Now you can take it for a drive around the block. Don't let the engine speed stay the same for more than 45-60 seconds. If you have to drive at a constant speed, shift the gears out often. You can drive it around for anywhere between 10 and 30 minutes. **Pay close attention to the gauges. If the engine overheats, shut the engine off immediately and tow it to be serviced no matter what the towing cost.** Overheating is here defined by the temperature gauge going anywhere above the halfway mark. If you drive the car overheated, it will cause metals to expand too much and ruin the bearings and rings.

** ) Notes: Do not allow the RPMs to exceed 4000. Do not bog the engine speed down. Drive the car like normal with throttle between 0% and 50%. Use the engine and shifting to slow the car down by downshifting the transmission. You can carefully downshift an auto transmission for this purpose.

6 ) Drive home or where ever you can park the car for a while. Let it cool down for several hours without being interrupted or started. Letting it cool overnight is fine too.

7 ) Seating the rings is very important. If the rings don't seat, the engine will burn oil. This must be done after the initial oil change and once the car is known to be sound to drive. At least one member on the forums rebuilt his engine without following the procedure to seat the rings. The result was a rebuilt engine that was burning lots of oil before it reached 500 miles.
Check the fluids level. To seat the rings, start the car and let it warm up for 15 minutes, watching for leaks. Keep an eye on the gauges during the entire procedure. If you can't use a dyno, drive the car to a long, flat stretch of road where you can drive at speeds between 30mph and 55 mph. This procedure requires consistency without stopping.

8 ) For a 5 speed car: Speed up until the car is in 3rd gear at 2500 RPMs. Then, push the throttle to halfway and let the car accelerate until 4000 RPMs. Then let off the throttle and let the car slow down in 3rd gear until it reaches 2500 RPMs again. **Do not use the brakes to slow the car down, do not push in the clutch, simply let the engine vacuum and gearing slow the car down.** When it reaches 2500 RPMs, immediately pin the throttle back to half way and let it accelerate to 4000 RPMs again. Repeat this a total of about 4-5 times.

9 ) Do a similar process as above, but do it at full throttle. 2500 RPMs until 4000 RPMs, and back down to 2500 RPMs. Repeat for a total of 4-5 times.

10 ) Now you will change the pattern a little bit. Nail the throttle at 100% from 3000 RPMs until the car accelerates to 4500 RPMs. Do not exceed 4500 RPMs. Then, let the engine vacuum and gearing slow the car down to 3000 RPMs. Immediately pin the throttle to 100% again and repeat this process 7-10 times. After this, you can consider the rings seated. Drive the car home or to the shop.

** ) Notes: Always watch the gauges and make sure the oil light doesn't come on and the engine doesn't overheat. If it does, stop the engine immediately and tow it to a location for servicing. Do not exceed 4000 RPMs at any time with the exception of seating the rings.

11 ) Get the car to some place for an oil change. The oil and filter should be changed immediately. There should be plenty of metal particles in the oil from seating the rings. You should also let the engine cool down for several hours or overnight. Then you can adjust the valves. The most important parts are done.

12 ) Drive the car like normal for 500 miles. Do not exceed 4000 RPMs. Do not let the engine stay at one speed for extended periods of time, like 5 minutes. When the engine has reached 500 miles, change the oil and filter.

13 ) Now you can drive the car like normal until it reaches the 1,000 mile mark after the engine rebuild. Do not exceed 6000 RPMs. Do not let the engine stay at one speed for extended periods of time. When the engine hits the 1,000 mile mark, change the oil and filter. Then, consider the rebuilt engine completely 'broken-in'. It should be safe to drive the car however you want to drive it.

** ) If the engine overheats at any time during break-in, shut the engine off and tow the car to a location for service. Remember that different metals expand at different rates. You don't want to mess up a new rebuild.

Failure to comply with proper engine break in procedure can result in damage to the engine.
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Please feel free to comment on this as you see fit. Perhaps I missed something. Many people are rebuilding their engines now and we need this information linked in our FAQ sticky. Any mod, please add it. (or just make me a mod and I will) :smilejap:
 

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this is in the manual isn't it? i think you did a good thing here, but all it really did was make it easier for people to not search for the information.
 

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Discussion Starter #3
The manual is very brief in explaining much of anything. It does list some items here, then other manuals like chiltons and haynes list other things. It's hit and miss so I wanted to collect it all together and list the details.
 

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I think this should be stickied, or at least put in the faq sticky with big bold letters or something :D
 

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Very sticky material!!

I do strongly disagree with step 3 however. Although I've done several head gaskets and only torqued the head down one time and they are still driving around today, it absolutely will not hurt at all to torque the head down again after one or two heat cycles. I've made this habit now on any engine I work on and had much better results.

Reason being I completely rebuilt a del sol (D16Z6) a few months back and the mult-layer steel head gasket failed on it after almost 1000 miles. Only torqued the head down one time. Replaced the head gasket with an identical MLS gasket, heat cycled it once, retorqued it again, and it's got several thousand miles on it now and still purring. When I torqued the head the second time, I got a quarter to almost half a turn on most of the head studs, torquing them at the proper rating. I was absolutely blown away that they were so loose after only one heat cycle.

I do believe this should be standard procedure on any rebuilt engine or head gasket job.
 

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Discussion Starter #7
Very sticky material!!

I do strongly disagree with step 3 however. Although I've done several head gaskets and only torqued the head down one time and they are still driving around today, it absolutely will not hurt at all to torque the head down again after one or two heat cycles. I've made this habit now on any engine I work on and had much better results.

Reason being I completely rebuilt a del sol (D16Z6) a few months back and the mult-layer steel head gasket failed on it after almost 1000 miles. Only torqued the head down one time. Replaced the head gasket with an identical MLS gasket, heat cycled it once, retorqued it again, and it's got several thousand miles on it now and still purring. When I torqued the head the second time, I got a quarter to almost half a turn on most of the head studs, torquing them at the proper rating. I was absolutely blown away that they were so loose after only one heat cycle.

I do believe this should be standard procedure on any rebuilt engine or head gasket job.
I agree. However, I've found when you torque the head down according to manual procedure (3 steps), it would certainly merit re-torqueing the head during break-in. Every head I've done the 3-step torque has needed re-torque.
However, now I always do a 5-step torque on the head. So far only one head gasket I've done this with actually had a loose bolt or two. Two bolts turned less than 1/4 turn. Even still, it does not hurt to check anyway.
 

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Question on the re-torqueing. Do you need to pull the cam shafts to re-torque? it looks like you would have to to get to all the head bolts.
 

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Discussion Starter #10
Question on the re-torqueing. Do you need to pull the cam shafts to re-torque? it looks like you would have to to get to all the head bolts.
Sorry for tardiness.

On the DOHC, you have to pull the cams. On SOHC, you can re-torque without pulling the cam.
 

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great info. and a sticky for sure. one thing people dont realize is that when your breaking in a motor you dont baby it. you get oil to the places it needs to be, then drive it a little agressive so the rings seat properly. ive seen many people baby the motor until 1000 mile mark and then smash on it and burn oil.
 

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ill be doing this in a few weeks, and i deffinatly am going to re-torque my head. now whats the best way to get the timing belt on and off the cam gears?
 

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OK just as an addition...

I've done many heads on these engines and have NEVER re-torqued the head after final installation and running.
and never had a single problem.
 

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I think part 2 needs adjusting a little as well.
'conventional' oil doesn't necessarily mean the same to all people. Maybe state that it should be mineral oil and not synthetic.
 

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Discussion Starter #16
So do I really need to re-torqued the head?
It can depend on a lot of factors. I re-torque some heads using certain head gaskets and find the bolts looser than torque spec. Sometimes, you will find they are just fine where they are.


Let me ask you this:
What do you have to loose in just checking that the head bolts are not loose?
:xmas:
 

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True Triple. It is just going to be a pain to pull the cams and redo the timing belt with the engine in the car.
And that is the reason Honda (and gasket manufacturers) give torque specs that mean you don't have to.
 

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great info. and a sticky for sure. one thing people dont realize is that when your breaking in a motor you dont baby it. you get oil to the places it needs to be, then drive it a little agressive so the rings seat properly. ive seen many people baby the motor until 1000 mile mark and then smash on it and burn oil.
sorry i read the post wrong....i was going to correct you but it was my eyes that needed correcting
 

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I've always wondered about this. I've heard it both ways. At work, I always warm the engine until the fans come on, change the oil and filter and let it go. They come back at 500 and 1000 miles for oil changes. Then at 1500, another oil change and a tune. These are Subaru engines, but that really shouldn't matter. This is just the way the shop likes it to be done.

When I rebuilt my Prelude engine, I didn't do this. I let it warm up to operating temp, then changed oil. Then, I went out on the road and started tuning the A/F's, taking it to redline multiple times. The engine has been fine for ~25k miles now. Last i checked, it was about 1/2 quart low on oil after about 2000 to 2500 miles, which is completely acceptable.
 
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