Timing chain cover question

Engine, Transmission & Driveline

  1. Rosco

    Rosco Member

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    I was wondering if anyone has an idea of the tolerance for my timing chain cover surface? I have it off the vehicle and had to repair a hole. The weld went onto the flat mating surface of the water pump and was ground off by hand with a handheld grinder. The surface is nowhere near perfect (surprise surprise) with maybe a 32nd showing under a straightedge where the weld material was ground off.
    Question is should I be concerned about a leak or would the gasket/gasket sealer take care of any imperfections?
     
  2. Davea Lux

    Davea Lux Old Man with a Hat FCBO Gold Member

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    It is a fairly big job to R & R the cover and a new one is not that expensive, replace it and save your self a lot of grief.

    Dave
     
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  3. thrashingcows

    thrashingcows Senior Member

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    How large or wide is the mating surface that is slightly damaged? Pics would help. ;) But if it were me I'd probably try running it just make sure to allow the RTV to completely set up and dry before putting any coolant back into the system.
     
  4. 70bigblockdodge

    70bigblockdodge Old Man with a Hat FCBO Gold Member

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    Assuming a small block?
    If it is just a pock mark in the gasket surface you could JB weld it and file flat.
     
  5. The Goose

    The Goose Senior Member

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    I had a 340 w a cover that dissolved like an alkaseltzer. I added JB weld every time it sprung a leak. Lasted about 8 years w no issues. When I finally pulled it apart the JB weld snake was about 3 feet long. The whole cover fell away from it. Pretty funny but worth it. Pain in the butt to yank so I field expedient repaired it until rebuild time. Bolts will hold it in place and JB weld will fix it but like Mr Dave said any doubt now is the time to replace it.
     
  6. 70bigblockdodge

    70bigblockdodge Old Man with a Hat FCBO Gold Member

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    You can tell from these post who are the mechanics and who are the truck drivers.
    :rofl:
    I love it!
     
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  7. The Goose

    The Goose Senior Member

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    283A0B57-ED18-4954-B80E-BD43BAED1576.jpeg
     
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  8. CBODY67

    CBODY67 Senior Member

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    A few Saturdays ago, our car club toured a high-end restoration shop and car sales venue. The manager noted that they had a backlog of 42 cars and were needing three more techs. Their service manager went to a regional automotive trade school that had about 160 students, but he said only THREE might be interested in that work. The instructor mentioned that he tasked one guy to check for an oil leak on a late-model pickup. The student got a creeper and rolled under the pickup. After about 15 minutes, the student hadn't returned, so the instructor went to see what was going on. He found the creeper with the student still on it. He kicked his foot and asked how he was doing. The student rolled out and said he'd been looking on YouTube to see where the oil leak might be and how to find it. We all laughed! Not a whole lot different from a dealership tech having to call Tech Assistance to find out what parts to order for a particular repair. So much for that!

    CBODY67
     
  9. Davea Lux

    Davea Lux Old Man with a Hat FCBO Gold Member

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    Somebody forget to tell the young tech to look up until oil drips in his face, leak found.

    Dave
     
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  10. Rosco

    Rosco Member

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    Well, seems to be mixed opinions on whether or not to run the cover...
    Most of the surface that the water pump mounts to has been messed with (ground with a sanding disc) so it's not just one spot. It's not terrible but far from machined.
    . Dave- is "R and R" a machine shop procedure? I am not at a place where a new cover could be obtained. Would you think filing the surface as best as I can by hand would be adequate?
     
  11. 70bigblockdodge

    70bigblockdodge Old Man with a Hat FCBO Gold Member

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    That is where I would go with it. If filing is excessive the pump may hit, just something to keep in mind. You have to do something other than replace because you will be waiting on a new one a while where your at.
     
  12. Rosco

    Rosco Member

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    That's exactly what I wanted to hear I just hope it works!! A better/more specific question would be how much of a void or gap can RTV reliably fill?
     
  13. 70bigblockdodge

    70bigblockdodge Old Man with a Hat FCBO Gold Member

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    Reliably? Not a whole lot. It is more for imperfections not filling gaps, although it does work in place of intake end seals if gasket is too thick because of machining.
    I would still be leaning toward putting a bead of 2 part epoxy (JB Weld name brand here) and let it harden then file flat.
     
  14. Rosco

    Rosco Member

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    JB's not really an option here as pretty much the whole surface has been altered. It'd be like a bead of JB over the whole mating surface and then trying to file that. Kind of the opposite direction I want to go after what happened here.
    There may be a shop in the big city nearby that could surface it for me otherwise I'm looking at self-filing and rtv.
     
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  15. PH27L7

    PH27L7 Active Member

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  16. Rosco

    Rosco Member

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    I was considering this but wrong part for my motor. Summit Racing, right?
    At some point in the late 80's I replaced my motor with one from a wrecking yard. The guys told me at the time that it was from maybe '72- It's been so long now I can't remember (my car is a '68). The timing marks on mine are on the left and the seal for the crank looks too big on the Summit part.
    I believe my manual says the engine id stamp is below the left side cylinder head- I don't see anything there but I do have marks on the intake. It would be nice to know what exact year/model my motor is from...
     
  17. PH27L7

    PH27L7 Active Member

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    Trying to fix a messed up one is pretty half assed as discussed. You have 2 options that I see. You can buy one of the new ones and find the older ('66?) bolt-on timing markers. Otherwise find one like yours that has the timing marks cast-in on left which were only used a couple years. I have one of those lying around you can have dirt cheap. It has some corrosion around the water inlets but had zero leaks.
     
  18. Big_John

    Big_John Illegitimi non carborundum FCBO Gold Member

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    Since the cover is off, and I assume you have the power steering off too, you should be able to see these identifying numbers. 1972 should have "H".

    With all your messing around with this, I think you'll be better off biting the bullet and replacing the cover.

    [​IMG]

    [​IMG]
     
  19. Rosco

    Rosco Member

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    Yes, half -assed but not able to wait for shipping for new part. I greatly appreciate your offer but won't be able to wait for shipping. (I'm in Mexico with the car). I had an opportunity to have a friend grab the 635-400 part for me (in stock in Sparks,NV) but it isn't right. So, I will be looking for a shop in La Paz to surface mine and hope with that and a lot of rtv it won't be a new problem once installed.
    Of course, this is the classic forum looking for someone to say it will work as is and that the gasket/sealer should be fine for the water pump connection. MOst of the feedback here leans towards trying to get my cover as flat as possible and not rely completely on rtv...
     
  20. Rosco

    Rosco Member

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    Yes, half -assed but not able to wait for shipping for new part. I greatly appreciate your offer but won't be able to wait for shipping. (I'm in Mexico with the car). I had an opportunity to have a friend grab the 635-400 part for me (in stock in Sparks,NV) but it isn't right. So, I will be looking for a shop in La Paz to surface mine and hope with that and a lot of rtv it won't be a new problem once installed.
    Of course, this is the classic forum looking for someone to say it will work as is and that the gasket/sealer should be fine for the water pump connection. MOst of the feedback here leans towards trying to get my cover as flat as possible and not rely completely on rtv...