Dr_Snooz
11-29-2009, 09:59 PM
Somewhere on here is a thread where I poo poo the Motoman engine break in (http://www.mototuneusa.com/break_in_secrets.htm) method. The irony is that it is exactly how I broke my new engine in. I'm not a racer and I want the car to last forever, so what happened?
The method prescribes a series of 4th gear WOT pulls up to red line. This is in complete contrast to what you'll read in any factory owner's manual. Honda tells you to avoid WOT, stay below a certain rpm range, etc. Going so radically against this advice unnerving.
Motoman insists that you won't get a good ring seal if you don't hammer the engine and he has lots of pictures of pistons broken in his way vs. the standard way. It does appear that there is more blowby in the standard engines. I definitely don't want blowby, so I had to consider his advice carefully. He states that you have to force the rings against the cylinder walls within the first 20 miles or the cylinder honing will be worn off and the rings won't seat...ever. The only way to prevent this calamity is by running the engine flat out.
This is one man's opinion, of course. What swayed me was reading around the web. All kinds of motorcycle riders, racers, auto racers and even airplane mechanics ascribe to his method. Not one single person relayed a disaster story. There were also a lot of stories about how car factories take engines off the production line, fire them up and run them right up to red line routinely. What clinched it though was all the old time machinists and engine builders who chimed in on the discussion boards with their own versions of Motoman's break in that they've used since the dawn of time. Guys with lots of engines under their belts were saying that the only way to get an engine to run well and long was to hammer it after the first start up. I was sold.
The engine did not blow up. Oil pressure is somewhere over 60 psi. Vacuum is near 20 Hg. Hooray! It runs quiet and smooth.
If you want to try it, be careful, 6000 rpm in 4th gear is north of 115 mph. Have a long runway and no traffic. Vacuum loading is as important as WOT pulls, so don't run up to red line and then brake. You want to coast with the car in gear back down to the prescribed lower rpm. When you are done, CHANGE THE OIL. It will be full of metal and you don't want that circulating through your new engine. Change the oil again after 500 miles. Once you've done the break in, you're done. Go out and have fun!
The method prescribes a series of 4th gear WOT pulls up to red line. This is in complete contrast to what you'll read in any factory owner's manual. Honda tells you to avoid WOT, stay below a certain rpm range, etc. Going so radically against this advice unnerving.
Motoman insists that you won't get a good ring seal if you don't hammer the engine and he has lots of pictures of pistons broken in his way vs. the standard way. It does appear that there is more blowby in the standard engines. I definitely don't want blowby, so I had to consider his advice carefully. He states that you have to force the rings against the cylinder walls within the first 20 miles or the cylinder honing will be worn off and the rings won't seat...ever. The only way to prevent this calamity is by running the engine flat out.
This is one man's opinion, of course. What swayed me was reading around the web. All kinds of motorcycle riders, racers, auto racers and even airplane mechanics ascribe to his method. Not one single person relayed a disaster story. There were also a lot of stories about how car factories take engines off the production line, fire them up and run them right up to red line routinely. What clinched it though was all the old time machinists and engine builders who chimed in on the discussion boards with their own versions of Motoman's break in that they've used since the dawn of time. Guys with lots of engines under their belts were saying that the only way to get an engine to run well and long was to hammer it after the first start up. I was sold.
The engine did not blow up. Oil pressure is somewhere over 60 psi. Vacuum is near 20 Hg. Hooray! It runs quiet and smooth.
If you want to try it, be careful, 6000 rpm in 4th gear is north of 115 mph. Have a long runway and no traffic. Vacuum loading is as important as WOT pulls, so don't run up to red line and then brake. You want to coast with the car in gear back down to the prescribed lower rpm. When you are done, CHANGE THE OIL. It will be full of metal and you don't want that circulating through your new engine. Change the oil again after 500 miles. Once you've done the break in, you're done. Go out and have fun!