Hi again, I'm here to post about a problem I've been having for a while now and to find any solutions to this issue. For the past 2 months, I've been trying to find the exact place of origin to this problem, and with the help of another use, ole4 (pretty sure that's his name), I've scoped it down to my cam. The problem is, is that when I'm pulling my engine over I hear this almost clunking/ticking noise. It's very consistent when it happens and only does it when the intake spring is compressed, exhaust spring is compressed, and when both are returning to their non-compressed states. I've looked all around the internet to see if anyone else had the same issue and I did find someone that did. But, the forum had no permeant solution to this issue, and only temporarily stopped it by using a washer as a spacer. To add onto the problem I am having, I am 99% sure it's my cam thrust play (pretty sure that's what it's called). At least that's what the forum was talking about. To answer a question that you may be have, no it's not my valves, I've checked twice and both clearances have came out to well over 0.125, so clearance is not an issue. It only started to make this sound when I installed 1. 45lbs dual valve springs, 2. Resize the valves to 28.5mm and 25mm, and 3. Install 1.3 black venom rockers. I have a billet flywheel and rod, hot-265 cam, and a pwk 26mm carb. I plan to add a flattop piston when I get this problem solved. Some ideas I've had were to use a billet side cover because it comes with shims and that might help. Another idea was to but cam shims, but I don't understand why because I've never had this problem up until now, could push rod length be an issue? I'm using 5.200 length (stock for 212) but I tried using 5.100 but they seem to be too small. Any help would be much appreciated, I really just want to get this thing done and out of my hair. Again sorry for posting some much about help, I hate it just as much as the next person. If there any questions you have, feel free to ask, I'll give any info if necessary.
Solution to a cam problem
- Thread starter Soppyslogster
- Start date
It could very well be your push rods. Did you just guess at the length or use a push rod tool to determine what you need? Once you start doing mods like these it's much more prudent to be exact with measurements. On my engine with the same rockers I had them measured down to the thousandth of an inch and went with the build your own ones. The length that was recommended for what I was running was so far off there's no way they would have worked.
You need to be careful when setting up those roller rockers. They're not as forgiving as your standard setup. Did you watch the video that Gage makes explaining how the geometry works with them? Having your push rod length off can cause issues.
If you do decide to get a billet side cover you'll need to have a dial indicator of some sort so you can measure crank end play to get it shimmed correctly.
You need to be careful when setting up those roller rockers. They're not as forgiving as your standard setup. Did you watch the video that Gage makes explaining how the geometry works with them? Having your push rod length off can cause issues.
If you do decide to get a billet side cover you'll need to have a dial indicator of some sort so you can measure crank end play to get it shimmed correctly.
Ok, so I swapped in the 5.110 pushrods and I remembered why they didn't work. They are too short, as in the 10 point lock nut can't screw around the adjuster, so those are out of the question. Also I saw a video that RGB posted only like a day or two ago where he disassembled a motor he built a while ago and mine was built almost 1:1 and he used shims to get fix his end play. Also I tried shifting my crank back and forth, it was making a clunking noise and was pretty noticeable that it was shifting back and forth.
Edit: Actually think its my inplay now because the crank shift back and forth look way more than 0.10
Edit: Actually think its my inplay now because the crank shift back and forth look way more than 0.10
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I have 3 different engines and they all do this 1 is built the other 2 are stock. You can only hear it when you turn the engine by hand and not when you pull on the pull start. I think it's just the compression realease because it only does it when valves are tight. I just ran them anyway and they're just fine my built 196 has like 20 hours on it and no problems
Yeah I got curious and spun over one of my engines by hand on the bench with the plug removed and hear this. Now that I think about it I remember hearing it when looking at the timing with a timing wheel a couple years ago.
It's not a concern. I had the side cover off a few weeks ago and it was way too clean inside to indicate a problem.
It can only be the comp release or the cam. There's nothing else there to make this sound. It doesn't sound like it's coming from the upper valve train.
It's not a concern. I had the side cover off a few weeks ago and it was way too clean inside to indicate a problem.
It can only be the comp release or the cam. There's nothing else there to make this sound. It doesn't sound like it's coming from the upper valve train.
Unfortunately that is the wrong way to set geometry on a fixed fulcrum rocker arm. That said if you are talking about the swipe line on the the lash cap that is good to at least tell you the valve is not getting close to an edge but your geometry could be way off and your ratio could be way off. I don't think this is causing your noise however but who knows. it did only start happening according to one of your other threads on this issue when you installed the new rockers, is that correct or did you change a lot of stuff all at once. Was the knock not there after changing the cam then started after the rockerarm installation?