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Will give a quick run down on my build. Put a reconditioned 4bta from acdengines.com in my 2002 jeep TJ. Is mated to stock tranny and transfer case. (NV3550 NP231) both where gone through and look over by zumbrota bearing and gear. Also have the dinky stock axles. (Dana 30 and 35) I built this jeep for for very little off road use in mind so I think it should hold up for awhile at least.

Anyway. Got it fully installed and running this week. Once I got it started I let it idle for around 40 min. Then took it out for a test drive. Noticed that at about 1700 rpm there was a ticking that did not follow any pattern what's so ever beside that it starts around the same rpm every time. I also seem to lose power at the same time. Could that just be because of the torque curve? Got it back in the garage and without a load it still makes the sound. At the same rpm. Just from listen with a ear it sounds internal but I could be wrong.

Thank you in advance and sorry if this is in the wrong section. This is my first post. :confused:
 

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Shouldn't be loosing power at 1700 rpm. That's where the engine starts to hit the peak of the torque curve. Not sure what your noise is. Have you checked the valve lash? Might need a mechanics stethoscope to try and track it down.
 

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Shouldn't be loosing power at 1700 rpm. That's where the engine starts to hit the peak of the torque curve. Not sure what your noise is. Have you checked the valve lash? Might need a mechanics stethoscope to try and track it down.
That's what I thought. Thank you. I have not checked valve lash. Probably has nothing to do with it but I will let you know anyway just in case it does. I have an oil leak seems like the rear main seal. Just drips in the same spot when at idle but when as the rpm rises it seems to leak more and be flung towards passenger side of vehical. My guess was it was getting on the flywheel and being flung out the little slit in the bottom of the bell housing.
 

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Is it producing boost?

Whats your oil pressure running at idle hot and off idle?

Have you adjusted the valves?

Could be an exhaust leak... with the hood up, crack the throttle by hand hard and see if you see any smoke around the manifold/turbo.

Where does the sound appear to be coming from? Top end? Bottom end? Injection pump area?
 

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Is it producing boost?

Whats your oil pressure running at idle hot and off idle?

Have you adjusted the valves?

Could be an exhaust leak... with the hood up, crack the throttle by hand hard and see if you see any smoke around the manifold/turbo.

Where does the sound appear to be coming from? Top end? Bottom end? Injection pump area?
Thank you for replying I found the noise yesterday. It was my own fault. Installed a cam sensor so my stock rpm gauge would read and it would rattle enough to contact every so often at higher rpm. I thought that was the cause right away but didn't see it contacting. But completely took it off and no more noise. bounce
 
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