Break In Procedure.. Your way?

[GotaT]

Ive recently rebuilt the top end (rings, honing, heads...) on my 2.4. Im wondering if I've got it right for breakin procedure

Since I only have new rings and honing: (no new cams)

Use Non synthetic oil for breakin... 10w30 is what I normally run Or should I begin running Different weight oil?

1 Drive the car to operating temp

2 Accelerate liberally not to exceed WHAT RPM? app. 4000??

3 Decelerate allowing the cars momentum to continue pushing the engine

All the while maintaning regular operating temp.

Do these simple steps for the 1st 500 miles THEN
Change Oil

4 Continue w/ the same procedure for the next 500 miles maybe increasing rpm's a bit.

Good enough??

[stevepaa]

I warmed mine for 20 minutes at the driveway, then drained oil and replaced oil and filter. Then warmed again and then drove it hard.
Find some hills if you can, and hard on the gas up and no gas down.
Did about 100 miles and changed oil again. Went 500 and changed oil again.

good luck

[RoninLB]

read the other break-in thread going on now

engine break - in - am I paranoid?? Mist from oil tank at idle

[mppickett]

Originally posted by stevepaa
I warmed mine for 20 minutes at the driveway, then drained oil and replaced oil and filter. Then warmed again and then drove it hard.
Find some hills if you can, and hard on the gas up and no gas down.
Did about 100 miles and changed oil again. Went 500 and changed oil again.

good luck

This is close to what I did. I used 20W-50 dino oi:
1. warmed up by driving lightly and then drve for 20 miles hard on the gas and then no gas at all (rev up wind down against engine compression). I stayed out of boost but ran it up to 6000 rpm on the rev ups. After 20 miles of this I changed the oil and filter.
2. next 100 miles lots of rev up and wind downs. Small amounts of boost (no more than .3 bar). Didn't take it over 6000 rpm. Changed oil and filter.
3. next 500 miles. just like #2. Changed oil and filter.

[1fastredsc]

I followed a guide used by some motorcycle engine builders. After a rebuild they will use the on off throttle method. Basically hard on throttle, but if you've rebuilt the valve train at all don't exceed any high revs. Once you've reached your comfortable max rev, let off the throttle and let the motor decelerate the car. The theory is that you load the rings hard, then when you let off the vacumm created during the exhuast stroke will suck any tiny bits out. This is supposed to give a solid build with tight sealing between the wall and rings.

[Jeff Alton]

Lifting off throttle also puts pressure on both sides of the rings. The motor needs to see some load. I too use the methods from that motorcylce tuner.

Cheers

[GotaT]

Perfect.. Thats what I've been seeming to do, Now, I have noticed in my rearview at night smoke exiting the ehxaust pipe while on throttle... Is this normal or not?.. did your car do this?
I find its hard to leave the car below the 32 to 3500 mark while just normally driving.
... BTW my car has a NA 2.4l 72 engine

[1fastredsc]

Carbs might need adjustment.

[GotaT]

Im pretty sure carbs do need adjustment. The car has a dead spot around 28 to 3000 rpms. Feels like its getting fuel then not and back and forth at these rpms. ... One note. I noticed that once the car is fully warmed up no smoke was coming from the exhaust pipe when on throttle and the engine Really quietened down as far as chain and rocker noise. sounds great.. I hope that once it is completely broken in it sounds this good even at startup. think so?

[1fastredsc]

I'm not sure, that's a subjective opinion. The general consensus though is that when a cold air cooled engine starts because of it's larger clearances, it's supposed to be noisy, rebuilt or not. I guess it's your call.