More important than you think!
By Steve Fox
Disassembly of the engine is probably one of the most important parts of the whole rebuild process. Now I am sure some of you probably think I have lost my marbles in saying so, but I think that is a true statement. There are several reasons why in my opinion and throughout this article, I will try and explain why that is.
First and foremost, normally an engine comes into the shop for a failure of some sort. Some of the common failures would be the engine making noise, oil consumption, parts failure, etc. At this point of the engine disassembly process, not only are you a teardown person, but you also become a detective. Yes, you read that right, a detective.
I would imagine that some of you never thought when you decided to work in the engine building/machining industry that you would ever be referred to as a detective. When you hear the word detective, I would almost bet you think of law enforcement and working crime scenes to figure out what happened. Well, that is no different in the engine building industry — we are all detectives!
Read this article with all images in the digital issue of Engine Professional magazine https://engineprofessional.com/2024EPQ2/#p=68
Crime scenes… how can you compare that to the engine building industry, some of you might be asking. Well, so many times, an engine will come into the shop to be repaired or rebuilt — and that is the crime scene. Whether or not there is a failure or not, all engines need to be inspected when disassembled.
Why was it using oil or making a noise? That is what needs to be investigated and looked at during the disassembly process to make sure that we solve the problem and make sure that during the rebuilding process, the problem was fixed so that the issue does not happen again. Take a look at the crime scene again — the engine. What do you see? How do you think this whole problem started?
Just like a detective in law enforcement, we need to analyze everything and make sure that we take good notes and pictures to reference back to so that we can do all we can to not have the engine come back with the same issue. Remember, this is the scene of the crime and we are trying to solve the problem.
Another reason why engine disassembly is important is to make notes and take pictures. You need to take notes about things that don’t look normal. Most of us have a smartphone that will take pictures, but if not, chances are someone working in the shop will have one that can be used for this.
Educate your teardown people on the importance of paying attention when disassembling any engine component. For instance, a common question that the tech line receives is camshaft cap location. These caps may or may not be marked from the factory. Always make sure to double check that before taking the camshafts out of the head. If you do not see any markings that you can make a note about, then mark them so you know the location that they go back to. A common way of marking them is front to back with I1, I2, etc. for intake and exhaust would be E1, E2, etc. Use an etching device so that you don’t damage the housing bore roundness using a stamp.
Making notes will help and assist in putting the engine back together for odd ball things like where a stud location is located in the main cap and what location. How many times have we had someone take an engine apart, not make a note of where that stud went and when it came back to assembly, they had no idea. Take the time to make notes on where things go as it will save you plenty of time down the road.
In the shop I worked at a long time ago, we had a clipboard with paper in the teardown room and would make a note of the customer’s name and engine that we were tearing down. I made plenty of notes and drawings to make sure that the assembler knew the correct location to install bolts or where certain things went. I did not want them coming back to me asking where the location was for this part or that part.
Sometimes the engines or cylinder heads come to the machine shop apart and there is nothing you can do about that. The customers actually think that they are helping you out by saving themselves money by tearing it down, but actually they are not. Your time is taken up trying to figure out where all these parts go during assembly. If possible, I would advise your customers to keep things assembled (as much as you want, we don’t need the all the accessories left on the engine) so that your shop can take them apart and know where things go.
Lastly, take measurements. Yes, AERA has a lot of specifications on over 14,000 engines, but we don’t have all of them. Even if we do, it is always a good practice to take and record those measurements during disassembly, this way you have something to reference back to during assembly.
The teardown/disassembly area of the shop is more important than we probably think and should be considered just as important as the other areas. Educating the person that does this job in your shop will help eliminate any confusion down the road as the engine passes through the shop.
Read this article with all images in the digital issue of Engine Professional magazine https://engineprofessional.com/2024EPQ2/#p=68