350 cam bearing interchange?

Discussion in 'Small Block Tech' started by MrSony, Dec 21, 2019.

  1. MrSony

    MrSony Well-Known Member

    I used a long jack handle covered in masking tape and a 3ish lb mini sledge. Light taps. Easy to go too far. I use a ziptie through the main saddle holes to check front to back alignment. If I can see the entirety of the width of the tie though the bearing oil hole (factory style bearings) I know the bearing is centered.
  2. patwhac

    patwhac Well-Known Member

    Thanks for the info and pics! Here's the tool I have:


    Looks like it should work the same way if I put the long rod through the block using the guide and attach the bearing support piece on the end after, if that makes sense?
  3. Mart

    Mart Gold level member

    Should work. You can get threaded hardware rod and big thick flat washers if needed to stabilize the bearing install. Measure blk bore face to oil hole and determine how far exactly you need to pull bearing in so oil hole is centered with blk oil hole.
  4. patwhac

    patwhac Well-Known Member

    Ok I might need to be sitting in front of my engine to make sure I'm envisioning this correctly...

    Makes sense to me! I'm sure it's kind of impossible to get a visual of the oiling holes once installed, though I do have a borescope . . .
  5. MrSony

    MrSony Well-Known Member

    Ok, so I installed the bearings a few days ago. Tried to put a spare cam (original cam from this motor) in to test fitment, was a little stiff going in (heh) but did go in. However once in, it locked hard. Suffice to say it ruined the bearings doing this, even being lubed with oil. I had to beat it out with a long socket extension through the back. I tried it again with just a left over new front cam bearing (used a TA one the first time). Bearing slid onto cam no problem. Once in the block, I would have had to use a deadblow to get the cam in. Old cam with old bearings came out fine. Whats the deal here? i get my hokey tool is probably the issue, but would it really distort the bearings that bad?
  6. Mark Demko

    Mark Demko Well-Known Member

    I had that issue with the '78 350 block I WAS running, the cam bearing bores were knurled, don't know if it was intentional from the factory or a screw-up.
    It made the cam very tight.
    I went back to my original '71 block for this latest build, NO ISSUES:cool:
    It could very well be!
    The real cam bearing installation tool has a centering cone.
  7. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    Just because you got the bearings to go in doesn't mean they are in right. There is a reason they make a special tool to install cam bearings.

    Good thing those weren't TA$$$ cam bearings! Those bearings need to go in straight and in line or you seen what can happen. The slightest tilt even .002" and you're gonna have problems, especially if you have a tilt on multiple bearings in different directions.

    Also when installing regular cam bearings you need to line up the oil hole in the bearing with the oil hole in the block. The 3 o'clock and 7 o'clock is for back grooved TA cam bearings. If you installed regular ones that way you won't get any oil to the cam journals.

    Not sure what kind of tools you have access to but if you have a cam you're not planning on using, you can use it to make an installation tool similar to what Mart has. Drill a half inch hole in the end cam journal, then cut it off and use washers and threaded rod.
    MrSony and 1973gs like this.
  8. MrSony

    MrSony Well-Known Member

    Yeah the regular ones were installed right. On the bright side the tool i made is an excellent bearing remover. :/
  9. TrunkMonkey

    TrunkMonkey Well-Known Member

    If any of the bearings are cocked even the smallest amount, the cam will be hard if not impossible to turn.

    If the tool is not square with the bearing and/or the bearing is not square with the bore, you will either get it cocked, or the bearing will deform, and it does not take much at all to do that. Hate to be the one to pee on the parade, but by the time you have found the bearing is "not going in straight", almost 100% it is been compromised.

    As the Buick front mounted oil pump V8s oil system are very much dependent on the #1 cam bearing being healthy, it has to be right.

    The front bearing should be installed from the back (the same as installing the rear from the front).

    The time, cost and hassle of screwing up the bearing install is worth the time and hassle of pulling the engine.

    Yeah, there are people who have replace them with engine in the car, but for every one that gets it done correctly the first time, there are hundreds that did not.

    Buy the correct parts. Buy/use the proper tools. Follow the best practices. Know your limitations.**

    **for those who did not read the waiver, "Overkill" was/is my call-sign.
  10. MrSony

    MrSony Well-Known Member

    Why should the front be driven from the back?
  11. MrSony

    MrSony Well-Known Member

    For around $5, a shaved down expansion plug is still an excellent bearing remover. Pops them suckers right out. I think the main reason my diy tool sucks is because it would actually deform. I have some 3/8 plate steel I can use in place of it and I ordered 2 full sets of bearings for testing. I'll try one of the 2,3,4,5 bearings with a revised tool. if that doesn't work, I guess I'm just going to bite the bullet and buy the correct $2-300 tool. One less thing I have to have the machine shop do. There's one of facebook marketplace for $200 now, it's been on there for quite a while, maybe the guy will lower the price some.

    Edit: Or this I found on ebay lol


  12. MrSony

    MrSony Well-Known Member

    Bought that tool from ebay, let's see where this goes.
  13. patwhac

    patwhac Well-Known Member

    The one I posted the link to above is only $100 and is supposed to be decent quality! It's not universal, they make the adapters specifically for each engine type.
  14. TrunkMonkey

    TrunkMonkey Well-Known Member

    The bearings have to be 100% dead on perpendicular (square) to the bore going in. Any deviation is likely to ruin them.
    Unless you have a guide that will keep the tool from any left to right from center (and creating an angle), you are going to be lucky to get it in correctly.

    That $60 tool will work for installing and removing bearings just fine.
  15. patwhac

    patwhac Well-Known Member

    Does anyone know if I'm able to fit a new front cam bearing into the rear area of the bore it's supposed to be installed in without removing the crankshaft? In order to press it in from the inside (rear). After thinking about it the crank seems to be the only thing that would be in the way.

    I guess I could just find out once I'm back at the garage if no one knows!
  16. TrunkMonkey

    TrunkMonkey Well-Known Member

    Is the engine in or out of the car?
  17. patwhac

    patwhac Well-Known Member

    Engine out of the car on a rotating engine stand. My plan was to not even breathe on the bottom end of this thing . . . Just cam, timing gear, timing cover, gaskets etc. Well, I guess welding in oil return fittings to the oil pan counts but I wasn't gonna break loose any rod or main bolts if I couldn't help it.
  18. TrunkMonkey

    TrunkMonkey Well-Known Member

    Out is good.
    Pull the rear cam core plug, put the tool in carefully from the back, attach the bearing mandrill slip the bearing on and tap it in.
    The idea is to use the length of the cam bore "tunnel" to center the tool and the bearing should drive in straight.

    Make sure the engine is secure so nothing "scoots" away while you trying to initially set the bearing.

    Pull the old bearing and use it a few times installing and knocking it out to get the hang of it. :)
    patwhac likes this.
  19. 300sbb_overkill

    300sbb_overkill WWG1WGA. MAGA

    Typically the crank needs to be out to be able to load the bearing on the tool, .....but you might be able to sneak the bearing through the lifter galley in between the lifter bores as long as there isn't to much casting parting line flash in the way?
    Mark Demko likes this.
  20. patwhac

    patwhac Well-Known Member

    Ya know I just realized that I'd have to also fit the centering cone into that space as well, so it looks like the crank will have to come out. Unless I can just install the bearing from the front? That will probably mess it up though.

    I've never pulled a crank. Can I leave the rod/piston assemblies in place and just pull all of the rod and main caps?

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