Acura 3.7L block replaced

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Thought I would keep everyone updated. This engine has 70K and was using about 1.5 qt per 2K miles. Factory authorized replacement.

Block replacement was completed yesterday. It came with a water pump but I had to pay for the belt and tensioner. The mechanic stated that the other parts were fine. Did not change the spark plugs because the dealer would not alter the labor charge whether the heads were out or not.

Got a chance to see the block. Dark oily carbon deposits on the piston crowns. Due to oil usage according to the mechanic. He theorized that the rings were coked up. All the pistons had equal deposits, but I could still see the relief cuts on the crowns.

Cylinder walls looked an even grey in color I guess due to the aluminum liners.

Looking for suggestions:
1. Break in. Easy (didn't work the first time) Hard (scares me)
2. First oil change? How soon?
3. Which oil viscosity? 5W-20 synthetic didn't seem to work the first time.
4. How often to change the oil to try to prevent stuck rings.

Thanks for your suggestions in advance.
 
I wonder if Acura gets the dealership to break it in for you? That would probably be a half hour of "extra hard" but you'll never notice or know.
 
Typically the liners are cast iron. I doubt the liners are aluminum. Liners are typically used in aluminum blocks or industrial engines where they expect to rebuild the engine with new liners and pistons.
 
It looks like you were running Valvoline conventional before, in such a high performance engine I'd be using synthetic, if you like Valvoline try Synpower, otherwise I'd recommend Pennzoil Ultra
 
Originally Posted By: Donald
Typically the liners are cast iron. I doubt the liners are aluminum. Liners are typically used in aluminum blocks or industrial engines where they expect to rebuild the engine with new liners and pistons.


There hypereutectic aluminum liners.

I'd drive it as you normally do for run-in. Don't baby it, but don't give it the full boot at every stop light either.
 
I'd break it in moderately hard and change the oil after 500 miles. Don't they say new engines need to be held at 3,000 RPMs for 30 minutes or something?

What was your oil change schedule before? I'd change it more often.
 
I have an honest question... Should you be looking to get rid of this car? You had issues with it this early on from the factory, I'm not sure I would trust a mechanic to put everything back together and have it run forever. Is the work warranted? Have you looked into if other Honda 3.7s have this issue? The car its wrapped around is truly a nice vehicle, but I would be looking to trade it in after this kind of work.

Aside from that for a break in I'd probably follow the original break in recommendation, which is probably something like dont exceed X RPM for 1,000 miles, then change oil. With that kind of oil consumption previously you'd notice a problem pretty quickly I'd think.
 
Originally Posted By: Nick1994
I'd break it in moderately hard and change the oil after 500 miles. Don't they say new engines need to be held at 3,000 RPMs for 30 minutes or something?

What was your oil change schedule before? I'd change it more often.



No, if anything you want to expose the engine to a wide range of conditions. Dependent on gearing, 30 minutes at 3000rpm might be well above posted speed limits.

Engine break-in is somewhat of an archaism at this point, if you ask me. Some manufacturers do have recommendations, but others don't -- because manufacturing tolerances have improved so much in the past few decades.
 
Originally Posted By: dparm
Originally Posted By: Nick1994
I'd break it in moderately hard and change the oil after 500 miles. Don't they say new engines need to be held at 3,000 RPMs for 30 minutes or something?

What was your oil change schedule before? I'd change it more often.



No, if anything you want to expose the engine to a wide range of conditions. Dependent on gearing, 30 minutes at 3000rpm might be well above posted speed limits.

Engine break-in is somewhat of an archaism at this point, if you ask me. Some manufacturers do have recommendations, but others don't -- because manufacturing tolerances have improved so much in the past few decades.
I had a TDI with a bad camshaft. I did some research for if I replaced it, and it was recommended to do X amount of RPMs for 30 minutes. That's in park or neutral, not driving.
 
Originally Posted By: 901Memphis
It looks like you were running Valvoline conventional before, in such a high performance engine I'd be using synthetic, if you like Valvoline try Synpower, otherwise I'd recommend Pennzoil Ultra


Actually, I ran synthetic the whole life of the car after the initial fill. The Valvoline conventional was the last oil change on the old block while waiting for the new one to arrive.
 
I like break in with a good load at moderate rpm. Its just as important to get some compression braking in too. I ran my wife's new Outback up and down a big grade right off the lot. Then used the paddles for 2 weeks after that.
 
Originally Posted By: MajorCavalry

3. Which oil viscosity? 5W-20 synthetic didn't seem to work the first time.


10W-30 Chevron Supreme
 
Originally Posted By: Nick1994
But how often did you change the oil?


I changed the oil when the motor monitor was down to 15%. About 6K miles. I think I will shorten that to 5K.
 
Originally Posted By: MajorCavalry
Originally Posted By: 901Memphis
It looks like you were running Valvoline conventional before, in such a high performance engine I'd be using synthetic, if you like Valvoline try Synpower, otherwise I'd recommend Pennzoil Ultra


Actually, I ran synthetic the whole life of the car after the initial fill. The Valvoline conventional was the last oil change on the old block while waiting for the new one to arrive.


Oil is irrelevant to your issues. I use olm as prior owner did on my 3.7 2007 mdx and it may use 1/2-1quart every 5k-8k which is oci. I have 150k on it.
 
+1 and I'm a fan of Chevron Supreme. I'd use it for break-in though
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The old rule of 2,000 RPM + for 20 minutes was for flat tappet cams. Not an issue here.

Run it in hill country on the throttle moderately, and back off for corners (compression braking). It'll settle down quickly. No redline runs until you have a 1,000 miles - then do it every once in a while
laugh.gif
 
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