- Thread starter
- #21
Haven't started it yet....about 99.9% sure everything is correctly installed and filled. I've just spent so much time in it tgat I SK t want it to NOT start, lol. Wish me luck, and thanks for all the help!
Proper 3F-E break-in procedures
- Thread starter Reconn1
- Start date
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- Thread starter
- #22
"installing it that I dont " not "in it tgat I SK t"
To expand a little bit here-
What is cam break in? Flat tappet cams and lifters are all lifters that are not roller tipped (I am ASSuming these engines use flat tappets, if they are roller lifters than there is no break in for the cam.
Flat tappet camshafts for production engines are always made from chilled iron. Chilled iron is just cast iron that is injected into a cold mold. When molten iron contacts a cold surface it actually transforms into an incredibly hard surface, it forms a carbide-like layer at the surface. The as-cast cam cores are then ground as they cannot be machined in any practical way, they are too hard on the surface. The cam lobes are ground at a tiny angle and the faces of the lifters are actually ground ever so slightly convex. This angle/convex stuff is incredbibly important and is what facilitates the lifters rotating so they don't just slide and gall. When you design things that need to slide on each other you NEVER use two of the same materials at the same hardness as they will gall against one another. The lifters are made from a certain material and hardened to be just a couple rockwell points softer than the camshaft.
When you're breaking in the cam what is actually going on is any imperfections in how the cam lobes and the lifter faces are ground and the alignment of the camshaft centerline/lifter bore machining in the block is being "averaged out" by all those parts running against one another. They are actually wearing into one another. The two purposes of revving the engine up for cam break in is 1 to accelerate the process and 2 to get oil flinging everywhere inside the engine to keep the cam lobes and lifter faces extra well lubed.
I always dump oil immediately after cam break in and change filters. There is a ton of microscopic iron particles in that oil plus all the break in lube. Get that crap out of there before it can hurt anything.
The point of varying the engine RPM between 1500-3000 RPM is because you can't see inside the engine, you vary the RPM slowly to ensure that if there is a "sweet spot" where the oil is flinging off the crank journals in just a perfect way to hit the cam lobes you're actually running the engine at that speed. That's the theory anyway.
Also, I think the #1 thing the first time engine breaker-inner (real word?) worries about is oil pressure and watching the gauges. This is probably the least important thing to worry about. Once you see the oil pressure gauge move it's no longer important. Your EARS are the primary sense here, if something sounds wrong then shut it down and figure out what it is. If the engine was put together right you can rev it to the redline and put it under full load as soon as it's started and nothing bad will happen, it's just not good practice. Crank bearings don't need to break in, valves don't need anything. They are all perfect before the engine is ever started and don't need any breaking in. If you didn't put any oil in your engine, didn't prime the oil pump, the engine would fire right up and probably be just fine for 5 minutes or more running on just the assembly lube that's all over everything. I've seen it on brand new engines that had mismatched oil system parts (a mismatched oil filter housing gasket among other things). The engine was run for atleast 15 minutes on and off before the problem was discovered.
Regarding the "cops won't like it" you don't need to speed, you just accelerate hard to a safe speed then slow down, even brake hard to get your speed down so you can accelerate again.
What is cam break in? Flat tappet cams and lifters are all lifters that are not roller tipped (I am ASSuming these engines use flat tappets, if they are roller lifters than there is no break in for the cam.
Flat tappet camshafts for production engines are always made from chilled iron. Chilled iron is just cast iron that is injected into a cold mold. When molten iron contacts a cold surface it actually transforms into an incredibly hard surface, it forms a carbide-like layer at the surface. The as-cast cam cores are then ground as they cannot be machined in any practical way, they are too hard on the surface. The cam lobes are ground at a tiny angle and the faces of the lifters are actually ground ever so slightly convex. This angle/convex stuff is incredbibly important and is what facilitates the lifters rotating so they don't just slide and gall. When you design things that need to slide on each other you NEVER use two of the same materials at the same hardness as they will gall against one another. The lifters are made from a certain material and hardened to be just a couple rockwell points softer than the camshaft.
When you're breaking in the cam what is actually going on is any imperfections in how the cam lobes and the lifter faces are ground and the alignment of the camshaft centerline/lifter bore machining in the block is being "averaged out" by all those parts running against one another. They are actually wearing into one another. The two purposes of revving the engine up for cam break in is 1 to accelerate the process and 2 to get oil flinging everywhere inside the engine to keep the cam lobes and lifter faces extra well lubed.
I always dump oil immediately after cam break in and change filters. There is a ton of microscopic iron particles in that oil plus all the break in lube. Get that crap out of there before it can hurt anything.
The point of varying the engine RPM between 1500-3000 RPM is because you can't see inside the engine, you vary the RPM slowly to ensure that if there is a "sweet spot" where the oil is flinging off the crank journals in just a perfect way to hit the cam lobes you're actually running the engine at that speed. That's the theory anyway.
Also, I think the #1 thing the first time engine breaker-inner (real word?) worries about is oil pressure and watching the gauges. This is probably the least important thing to worry about. Once you see the oil pressure gauge move it's no longer important. Your EARS are the primary sense here, if something sounds wrong then shut it down and figure out what it is. If the engine was put together right you can rev it to the redline and put it under full load as soon as it's started and nothing bad will happen, it's just not good practice. Crank bearings don't need to break in, valves don't need anything. They are all perfect before the engine is ever started and don't need any breaking in. If you didn't put any oil in your engine, didn't prime the oil pump, the engine would fire right up and probably be just fine for 5 minutes or more running on just the assembly lube that's all over everything. I've seen it on brand new engines that had mismatched oil system parts (a mismatched oil filter housing gasket among other things). The engine was run for atleast 15 minutes on and off before the problem was discovered.
Regarding the "cops won't like it" you don't need to speed, you just accelerate hard to a safe speed then slow down, even brake hard to get your speed down so you can accelerate again.
- Thread starter
- #24
Awesome, great write up, thank you for your time!!!!
During ring seating you expect higher than normal oil consumption. To the point that you should check oil level every tank of gas. Or sooner. Once your rings seat your oil consumption will drop drastically. Probably down to 1qt/3-5000 miles, which is what I'd consider totally acceptable oil consumption. At that point I'd run Dino oil for one or two complete oil change intervals of 5-8000 miles. Then switch to synthetic if you want.
The idea is that synth oil is super slippery and will inhibit the seating of the rings. You want them fully seated before switching to synth.
/2cents/
- Thread starter
- #26
What if I don't have the time right now to go thru rev break-in, oil change then drive? Can I do rev break-in and oil change, then come back the next day to drive the hills?
No problem with that.