new engine break-in initial fire = SPOUT out?

rockin_rick

Member
Oct 9, 2003
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I am getting ready to fire my new engine for the first time. I plan on letting it idle ~1500 rpms for 30 mins. I am also a first time Tweecer user, and concerned that wrong settings could hurt the new motor.

Would it be OK (or even a good idea) to remove the SPOUT plug for this entire 30 min fast idle run? That would then be like a hardwired spark advance limiter setting advance to distro position (10°), and GUARANTEE that detonation is not possible, right?

I could then gather datalogs and verify adavace commanded during this 30min idle. Then re-install the plug when done, before the first drive.

Is this a good plan for detonation prevention?

Rick
 
Rick, I'd suggest starting it up just with the stock EEC so you do not have to worry about any intial issues with the TwEECer. You can leave the spout out to set the timing then plug it back in, make sure your fuel pressure is at 38psi to start, then when you get it running turn the idle screw on the TB in to keep it on fast idle to break the cam in. Drain the oil, change the filter then do it again at 500 miles.
 
I think the other Rick is spot on. You don't have to worry about detonation with no load on the engine (sitting in the driveway). You should start it stock and get it running/idling correctly before you start "tweecing". If it's a roller cam - you needn't worry about any "30 minute" break-in period. Just fire it up, check for leaks/noises, set the timing with a light. If all's clear - you can drive away - and on the drive when you load the engine - that's when you can listen for detonation. If it's a flat tappet cam and you do have cam break-in to go through - yes, you can set the timing static at 10 or 12 and leave the spout out. But it's not necessary - with no load on the motor and relatively low rpm, it's not gonna add a bunch of timing anyway.
 
I got the 30min idle time from searching out and reading lots of posts on new engine break-in. I realize that it's not for my hyd. roller cam, but I thought that it would be just good for the engine. I plan on letting it idle for 30 mins, then changing the oil and filter, and letting it cool (giving it a heat cycle). Then taking it on it's initial drive. I got the impression from reading other posts that this is the reccomended method suggested by DSS for their engines. I thought that the heat cycle would be good as it's a new (not seasoned) block, and I'd like to slowly relieve those internal stresses.

I know that there is a lot of grey area here, I'm trying for the overly cautious, take no chances, obsessive method. That's just me. I've spent almost 3 months rebuilding this car, and have done everything that way. Why stop now!?!?

Have I gone overboard? Should I just not worry about this initial idle run, and go drive it a bit?

Rick
 
Naw - nothing overboard about it - careful is best. If it were mine, I'd check for leaks, noises and oil pressure. Assuming all is good, with the eec stock, I'd set the timing around 10-12 spout out, then put the spout back in, and I'd go for an easy ride. See what you learn. It'll come to operating temp much quicker that way and you can see what happens to things as the coolant system gets pressurized. Letting it idle won't tell you much of anything other than the initial check for big leaks and noises. But if you clear that and have pressure (oil), go for a short ride. What I try to do is keep it in the neighborhood - so if I do have a problem, I can get it back to the house more easily. Good luck - I know what you're going through. I actually procrastinated starting mine - like you, it'd been down for 2 or 3 months, and I kept thinking there was some other way to know it was ready. But there ain't. You primed the oil system through the dizzy hole?
 
Yep once I get it primed and started I check the oil pressure, fuel pressure, timing, make sure the coolant is flowing and bring it up to temp, check for leaks, make sure jo wires are rubbing anywhee etc... drain the oil change the filter. I have started opening up the filters after the first oil change to inspect how things are going. I then add new oil and filter and take it out for a short drive, constantly scan the gauges, make sure it runs cool, no over heating etc... Vary the rpms but don't wail on it yet.

I am a little old school and I like to break the motor in for 500 miles before a WOT blast, if you have a new clutch it is easy as most take a 500-600mile breakin anyways.
 
Pretty much agree with all the above...Isn't the "break in period" more for the rings instead of the roller cam now?? Vary the RPM and load or speed if driving to give them a chance to seat....

Don't even know if thats much of an issue anymore...My 03 F250 even recomended synthetic oil right from the get go...Heard that was a no-no with new rings...

Still I don't think I'd wail on it or even fool with the tweecer for 500-1000 miles...Better safe than :(