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Cam Break In - Tips for Avoiding Wiped Lobes?

Discussion in 'Engine & Performance' started by 79dentside, Apr 23, 2021.

  1. peats

    peats Full Access Member

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    thumper cam?? what a waste.
     
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  2. Matt69olds

    Matt69olds Full Access Member

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    I have heard from a few people running the engine with a couple extra quarts of oil. The theory is the crank spinning in the overfilled oil pan will splash oil onto the camshaft. Since the engine isn’t under a heavy load, or extremely high rpm, even if there are some foamy oil in the oil galleys, it won’t hurt anything.

    I really wonder about this one, the idea of splashing oil onto the cam abd lifters is great, not so sure about the potential foamy oil.

    Personally, make sure beyond a shadow of doubt the distributor is installed and timed correctly. Fill the float bowl of the carb so it’s ready to instantly fire without excessive cranking. Have lots of auxiliary fans and a garden hose ready to help keep the engine from overheating during the break in period. Use break in oil, with break in cam supplement. After the break in period, change the oil, cut open the oil filter to check for debris.
     
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  3. BillK

    BillK Junior Member

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    Which valve springs are you using ?
     
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  4. 79dentside

    79dentside Full Access Member

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    Sounds like I shouldn’t have issues... knock on wood. I am pretty familiar with the processes, I was just hoping to get some trucks to not wipe a lobe. Sounds like if you just do it right, there shouldn’t be an issue. Thanks all

    I understand, but it’s just my old beater. I’m not racing at all, I seldom go over 2,500 rpm. I know that my brakes will be impacted, but that’s okay. I’m just a motor head that want a little bit of a tune to it.

    I planned on using whatever springs are in my motor. The cam is only .479 lift, I’m not really sure what springs are in the crate motor currently. Unless there are any strong objections?
     
    Last edited: Apr 26, 2021
  5. 79dentside

    79dentside Full Access Member

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    Follow up on my timing issue. I’ve been mistaken on my TDC mark. Whatever I did the first time I ended up on the 2 o clock timing indicator.. not sure how or what I did to declare that.. anyways. I rotated the motor by hand until I hit the compression stroke of #1 (ironically it was my first turn of the crank lol)

    Anyways, I rotated it until the hissing of air past my finger was slowing down and right before it stopped hissing, I went up to check the balancer location. This is what I found on the 12 o clock indicator. Balancer mark is at like 1 degree BTDC and I wasn’t even using the balancer to find TDC at all, it just happened to be that close. I think the balancer may be close... what could cause my weird total timing fiasco? Could timing chain stretch cause that?
    [​IMG]
     
    Last edited: Apr 28, 2021
  6. 79dentside

    79dentside Full Access Member

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  7. Bextreme04

    Bextreme04 Full Access Member

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    That's what I have going into mine. It was the only set I could even find available... from anywhere. Lifters are in major backorder right now.

    For timing, you need to have a hard piston stop on cylinder #1... You then rotate the crank all the way around clockwise until it makes contact. Put a mark on the balancer where the "0" lines up. Rotate the crank all the way back around counterclockwise until it makes contact again. Place another mark on the balancer where it lines up with the "0". Halfway in between those marks is mechanic TDC. I've used the proform one and it works well. https://www.amazon.com/Proform-6679...ocphy=9032964&hvtargid=pla-448687787246&psc=1
     
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  8. 79dentside

    79dentside Full Access Member

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    I actually have that same piston stop tool already, the balancer mark is dead on.

    Regarding the lifters, I called Comp and asked why my set did not come with the hardened foot. I was asked if I was talking about the line on the side, I said yes. They told me that it is just a manufacturer mark, all lifters are hardened. I guess they get their lifters from multiple sources??
     
  9. SirRobyn0

    SirRobyn0 Full Access Member

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    I wanted to comment a couple days ago about cam break in, but didn't as time has been short and I get pulled away from the computer so I'll just say I see you have already received a bunch of great advice. The only thing I have to add is that it is not highly sensitive. Yes, it's important that you break the cam in, and following the manufactures directions is the way to go. I personally do not really buy into the zinc thing to much, but on the other hand for break in it's cheap insurance. So I'd run high zinc for the cam break in. Run the engine at the RPM and duration that the manufacture asks you to. But if something happens. For example if the engine starts to get hot and you need to shut it down to cool and add coolant that is not a big deal at all. I've installed many engines at the shop and we've done some standalone cams to, and we've never once wiped a lobe.
     
  10. SquareRoot

    SquareRoot Full Access Member

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    All lifters should be hardened...except the Chinese no care bout dat.
     
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  11. WesN

    WesN Full Access Member

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    View attachment 186527
    Is your harmonic balancer pushed all the way on? I took a pic of my 350 it is a little blurry but you can see the balancer is under the timing tab. The silver tape is a homemade timing tape. If you tried to use the inductive pickup in that round tube on the timing tab there is nothing below it to detect.
     
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  12. WesN

    WesN Full Access Member

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    3E00C6F8-A632-4868-A54D-B498E01B98C6.png
     
  13. 79dentside

    79dentside Full Access Member

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    Doesn’t look like it is! My balancer does appear to be pushed out doesn’t it.... well it’ll be fixed with this anyways hahaha.
     
  14. SirRobyn0

    SirRobyn0 Full Access Member

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    That could be a sign that it's coming apart and "walking" on the rubber.
     
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  15. 79dentside

    79dentside Full Access Member

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    Good call, you might be into something.
     
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