Once again a very good video! Thank you for taking the time to share this knowledge with us! PS Would love to see a video on rebuilding the CIS system. 😎
Kurt. Great video. You answered some of my questions on start up but I have a few more. When you start a freshly rebuilt 911 engine do you crank it without fuel and spark to make sure it has oil pressure first ? How long do you let it run for and at what RPM. I have heard that it should run for 20 min. at 2,500 RPM’s then shut it down and drain the oil. I’ll go with what you say. Thanks in advance,
Kevin, So when it comes to engine start-up, there can be a lot of miss information floating around out there. According to Porsche, all engines should be started on the engine dyno for break-in under load. It takes about an hour at different RPM and load settings and still requires the 2000-mile break-in driving schedule that is outlined in the owner's manual. In reality, not many of us have access to an engine dyno (Myself included). I Am not usually concerned about getting oil pressure. The way the Porsche 911 is set up with the oil tank, the pump is pre-primed by the weight of the oil sitting on the gears. 90% of the time, I will have oil pressure before the engine even thinks about firing. When the engine fires, I will vary my RPMs and will let the engine run for a few minutes while I get timing and mixtures close. What I don't want to do is go to 2000 RPM and sit there for 20 minutes. This is a great way to glaze up the cylinder bores. This can become an issue if you are using aftermarket cams, however. My goal is to get the engine under load as soon as I can; the best way for me to do that is to drive the car. So as soon as I can, I will get the car on the road. When I am driving, I will mimic the engine dyno break in spending 10 mins at 2-2500 under light load, 10 mins at 3 -3500 with a medium load, 10 mins at 3500 - 4000 medium load, 10 mins 4000 - 4500 Medium heavy load, 4500 - 5000 Medium heavy load, and 5000 - 5500 Medium heavy load. I use the gears to change the load and vary my RPMS as much as possible. Freeways late at night or early in the morning are great for this. When it comes to "Running in the cams," this is a result of aftermarket parts. The factory camshafts are nitrated and are very hard. The way the lubrication system is set up also insures good oil coverage to both the lobes and the bearings. When it comes to aftermarket cams, often the hardening process they use is not as good as the factory cams. So by running the engine at 2000 RPM, they are asking you to finish the hardening process by working hardening the surface of the cam lobes. The 2000 RPM is a holdover from American V8 engines. Most American engines will lube the cam lobes with oil splash off the crank. When the engine is running under 2000 RPM, the amount of oil slung up to the camshaft is not sufficient enough to keep a non-work-hardened camshaft alive. So hence the 2000 RPM number. I will usually do my first oil change around the 200-mile mark just before I give the car back to its owner. I will also do my cylinder head re-tension, rocker arm tension, and valve adjustment at the same time. Hope that helps explain the process. Kurt
Kurt, thank you also for this clear and concise procedure. I’m getting ready to install a top end rebuilt 964 engine and this was the last piece of the puzzle. It is especially valuable that you take the time to explain WHY things should or should not be done. Truly appreciate the knowledge and experience you share.
Articulated well. Wonderful vid. Looking for a bit more context on the distributor body rotation demo and finding the right position. Was this procedure b/c you rotated the dist body earlier or standard procedure? Couldn’t see what was going on w the points. Light blew out detail.
what i was doing by rotating the distributor body was getting the points so that they had just opened. This is because the ignition fires when the points open. By setting the engine position to TDC #1 and setting the distributor body to where the points have just opened makes it easy to start the engine the first time .We will be doing another video on this using a Bosch distributor and will make sure that the detail is better.
Loving this series!
Thanks John, S
Nice work!
Thanks!
Another amazing video. Thank you for your knowledge
Glad you enjoyed it!
and thanks for watching
Thanks so much for making these videos. I will use the series on the trans as a guide when I attempted to rebuild my gearbox. Great work.
thanks Michael,
Good luck with your transmission rebuild.
Outstanding
Thanks Charles
Good work sir
Thanks
Kurt
Once again a very good video! Thank you for taking the time to share this knowledge with us! PS Would love to see a video on rebuilding the CIS system. 😎
Roel,
Thank you, and yes we have filmed a CIS system rebuild and diagnostic. It should be out soon.
Thanks for watching
Kurt
Thank you so much for this video!!
Glad it was helpful!
Kurt
Kurt. Great video. You answered some of my questions on start up but I have a few more. When you start a freshly rebuilt 911 engine do you crank it without fuel and spark to make sure it has oil pressure first ? How long do you let it run for and at what RPM. I have heard that it should run for 20 min. at 2,500 RPM’s then shut it down and drain the oil. I’ll go with what you say. Thanks in advance,
Kevin,
So when it comes to engine start-up, there can be a lot of miss information floating around out there. According to Porsche, all engines should be started on the engine dyno for break-in under load. It takes about an hour at different RPM and load settings and still requires the 2000-mile break-in driving schedule that is outlined in the owner's manual.
In reality, not many of us have access to an engine dyno (Myself included). I Am not usually concerned about getting oil pressure. The way the Porsche 911 is set up with the oil tank, the pump is pre-primed by the weight of the oil sitting on the gears. 90% of the time, I will have oil pressure before the engine even thinks about firing. When the engine fires, I will vary my RPMs and will let the engine run for a few minutes while I get timing and mixtures close. What I don't want to do is go to 2000 RPM and sit there for 20 minutes. This is a great way to glaze up the cylinder bores. This can become an issue if you are using aftermarket cams, however.
My goal is to get the engine under load as soon as I can; the best way for me to do that is to drive the car. So as soon as I can, I will get the car on the road. When I am driving, I will mimic the engine dyno break in spending 10 mins at 2-2500 under light load, 10 mins at 3 -3500 with a medium load, 10 mins at 3500 - 4000 medium load, 10 mins 4000 - 4500 Medium heavy load, 4500 - 5000 Medium heavy load, and 5000 - 5500 Medium heavy load. I use the gears to change the load and vary my RPMS as much as possible. Freeways late at night or early in the morning are great for this.
When it comes to "Running in the cams," this is a result of aftermarket parts. The factory camshafts are nitrated and are very hard. The way the lubrication system is set up also insures good oil coverage to both the lobes and the bearings. When it comes to aftermarket cams, often the hardening process they use is not as good as the factory cams. So by running the engine at 2000 RPM, they are asking you to finish the hardening process by working hardening the surface of the cam lobes. The 2000 RPM is a holdover from American V8 engines. Most American engines will lube the cam lobes with oil splash off the crank. When the engine is running under 2000 RPM, the amount of oil slung up to the camshaft is not sufficient enough to keep a non-work-hardened camshaft alive. So hence the 2000 RPM number.
I will usually do my first oil change around the 200-mile mark just before I give the car back to its owner. I will also do my cylinder head re-tension, rocker arm tension, and valve adjustment at the same time.
Hope that helps explain the process.
Kurt
Kurt thank you for that in-depth answer to my question. Truly the best explained Porsche engine break in method I have read. Again thanks.
Kurt, thank you also for this clear and concise procedure. I’m getting ready to install a top end rebuilt 964 engine and this was the last piece of the puzzle. It is especially valuable that you take the time to explain WHY things should or should not be done. Truly appreciate the knowledge and experience you share.
Articulated well. Wonderful vid.
Looking for a bit more context on the distributor body rotation demo and finding the right position. Was this procedure b/c you rotated the dist body earlier or standard procedure? Couldn’t see what was going on w the points. Light blew out detail.
what i was doing by rotating the distributor body was getting the points so that they had just opened. This is because the ignition fires when the points open. By setting the engine position to TDC #1 and setting the distributor body to where the points have just opened makes it easy to start the engine the first time .We will be doing another video on this using a Bosch distributor and will make sure that the detail is better.
Good 👍
Thanks
Kurt
👍👍👍👍👍 again
Thanks again