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Thread: Opinion on timing

  1. #1

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    Opinion on timing

    Evening Gents,
    I have what I believe is probably a basic automotive question that I feel like I should know the answer to. I recently changed the timing belt on my truck. While I feel like this is typically a pretty simple process, mine was a bit of a challenge. When my crankshaft Mark is at tdc, the cam and injector pump are way off their timing marks. It feels like they are both almost mid stroke. I had to Mark them and clamp them in place to swap the belt and keep things at least setup the way it was. The truck runs but I don't feel like it sounds right so I would like to check timing. What do you think my best approach to this issue should be?

  2. #2



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    Ok so you have a diesel. Well the timing is extremely critical. You can easily get it off by 1 tooth. Injection needs to start around 17 deg I think. Re check everything and make sure things don't roll back when tighten up the belt. Do you have a manual?
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  3. #3

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    At the moment I only have the manuals I've been able to locate on the site here. More than willing to buy one, just haven't come across one in my searches. I know that the timing is pretty much exactly what it was before the belt replacement, I marked where it was originally and reworked everything a dozen times or so until i had it exact, and it runs the same way it did previously. My concern is that it was never right before. I wasn't sure how the pump and cam could be that far off when the crank is TDC and still run lol (but likely just my lack of knowledge). It idles fine, and run/drives without issue, it just doesn't sound quite right in comparison to some of the sound clips I've listened to.

    I guess my biggest question here that I should've asked, can the crankshaft pulley be installed more than one way, or is it a safe assumption that all the timing marks are correct? The engine has been rebuilt to some extent so I really have no clue what's been done to it.
    As an example, here's a pic of the cam shaft sprocket while the crank is at TDC.
    0125151049.jpg

  4. #4

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    Do you have a video of it running?

  5. #5

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    I do now! Really appreciate you guys checking it out.

    Here's starting and idling.


    Here's just idling.

  6. #6

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    I'm no expert but it sounds pretty diesel-y to me.

    Quote Originally Posted by donvier View Post
    It idles fine, and run/drives without issue, it just doesn't sound quite right in comparison to some of the sound clips I've listened to.
    I think you have new owner anxiety because its an engine of unknown provenence. YouTube clips aren't a good benchmark because who know what mods they have, how bad the mic is, age of the vehicle, etc. etc. Drive it around, keep track of oil and fuel consumption, listen for noises. Usually if something's wrong, the engine will let you know. If you think there's an issue take it to a pro shop that knows diesel for a checkup. It's possible to spend years chasing your tail and phantom problems.

  7. #7

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    I'm sure you're probably right. This is my first MM, AND my first diesel so I'm definitely paranoid. I appreciate you taking a listen. I'm excited to move on to the next thing on the list!

  8. #8

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    Take it to a diesel shop and have them give it a once over. The peace of mind will be worth the cost of the inspection.

  9. #9



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    The engine is smooth at idle and not jumping around. There is no surging, no missing, no funny sounds, though diesels are the noisiest friggin engines you can own. lol. Other then that, how's a test drive feel. Looks and sounds like the engine is doing pretty good. Started right up with a turn of the key, your work seems good to me.

  10. #10

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    Seems to run without any issue. I've yet to have it up to any high speed since it got pretty warm on the maiden drive home. I'm working on the cooling system at the moment lol. That being said, it ran awesome to the gas station and back the other day. I'm just a bit paranoid because of not having all the timing marks match up with the crank at tdc. It does run pretty rough for a few seconds on cold starts, but I think that's mainly because I'm still getting used to the manual glow plug situation. Would love to put the stock glow plug system back in place at some point. When I first recorded the video I had my phone set on UHD so it was huge, so what you're seeing there isn't a completely cold start, but it only ran for about 60 seconds the first round, still pretty cold.

  11. #11

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    The marks not lining up is weird. I would get a sanity check at a shop.

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