Idle motor noise December 19, 2016, 11:19:57 PM So I've had this noise for years, but never really dealt with it. I recently found some videos that show the noise, although I believe these are louder than my car (when I try recording with a mic, I mostly get exhaust note).Before this guy revs the engine, there's what appears to be louder noise in/above one cylinder: https://youtu.be/wf8e_Ivi72Q?t=9A louder version: https://youtu.be/SiNBHO21Vks?t=152This may also be close: https://www.youtube.com/watch?v=7dEPA9LDhdIWhat is this noise? I've tried pulling one plug wire at a time - no change in sound. It is only there when the car idles down to 700rpms - it goes away with any rpm/throttle increase. Not noticeable at 800rpms (let off throttle, the IAC drops to here before then taking the next step down to min idle). It's not there when cold - only when warmed up (rpms higher when cold). I had this same noise when I had gt40p heads, roller rockers, and different lifters. It is still there with TW heads, TW rockers, and my current crane hydraulic lifters. Every lifter has the same preload. It has just driven me crazy for years, especially when the car was daily driven many years back.I'd think it was lifter noise, but I believe I've had three different sets through the years when chasing the source, and two different sets of rocker arms. I even tried adding more preload years ago (closer to .060 on the gt40p heads, and the noise never went away. Oil gushes out of all eight rockers when running, seen years ago by the covers being left off and toweled-off for splatter.Just curious if anyone knows how I can quiet down what appears to be one cylinder always making this racket. I don't recall this sound ever being different in the 20-30k miles since the motor went from stock to everything rebuilt/aftermarket many years ago. This is the only odd noise the motor has made and many times had made me want to swap the engine for something with less noise up front.edit:And yes, I checked pushrod length before ordering the correct ones years ago. Not the cause of problems. I'm sure I posted plenty of pictures years ago of this stuff. Quote Selected
Idle motor noise Reply #1 – December 20, 2016, 11:06:36 AM Have you checked your pushrod guide alignment? If the pushrod is making contact with the cylinder head just loosen the rocker studs and realign the guide(s) so that there is no contact. This is in the literature for my Edelbrock heads so I figure it would apply to all heads. As a last resort you could send your rockers back to TW to have them check them out. Quote Selected
Idle motor noise Reply #2 – December 20, 2016, 02:55:50 PM Quote from: Aerocoupe;458574Have you checked your pushrod guide alignment? If the pushrod is making contact with the cylinder head just loosen the rocker studs and realign the guide(s) so that there is no contact. This is in the literature for my Edelbrock heads so I figure it would apply to all heads. As a last resort you could send your rockers back to TW to have them check them out.Almost certain it was fine, but I haven't done much with the car in almost 5 years. I don't remember many details from back then.I don't understand they the noise would have persisted between old iron heads and these aluminum heads, with different pushrods, lifters, and rocker arms. I would think it's bottom end, but other than the noise, and no change by pulling plug wires, and no change in tens of thousands of miles (if my memory serves me correctly), I'd think the shortblock was also okay.As you can imagine from the above clips though, it's annoying for sure. This has been the biggest push for me to want to move to a mod motor. Quote Selected
Idle motor noise Reply #3 – December 21, 2016, 03:20:17 PM I think I remember you working on the valve tip pattern on your valve train or maybe it was someone else. It sounds like you have that squared up but you have an issue in the short block. About the only way to figure that out is to tear it down and start looking. Not what anyone wants to hear but I would rather tear it apart and find out it was something easy than fiddle around and waste another year looking for it. Even if nothing is wrong with the short block you have then ruled it out.Just in case the mid-lift theory is about the best way to set your valve train up from what I get from machinists and engine builders alike:http://www.mid-lift.com/PUB/PUB050206PA.pdfThe only other thing I can think of is if you are running a automatic trans that something is fishy there but I am allergic to autos so I am no help there. Quote Selected
Idle motor noise Reply #4 – December 21, 2016, 05:49:46 PM Quote from: Aerocoupe;458586I think I remember you working on the valve tip pattern on your valve train or maybe it was someone else. It sounds like you have that squared up but you have an issue in the short block. About the only way to figure that out is to tear it down and start looking. Not what anyone wants to hear but I would rather tear it apart and find out it was something easy than fiddle around and waste another year looking for it. Even if nothing is wrong with the short block you have then ruled it out.Just in case the mid-lift theory is about the best way to set your valve train up from what I get from machinists and engine builders alike:http://www.mid-lift.com/PUB/PUB050206PA.pdfThe only other thing I can think of is if you are running a automatic trans that something is fishy there but I am allergic to autos so I am no help there.Yeah - I was hoping to hear some difference by pulling plugs while running (something I had never done). I've also seen many comments by random internet people claiming similar sounds as being anything from a timing chain to a flexplate. I have a different 4r70w in there as of months ago - nothing different. I did spend a lot of time on my rocker arm setup, and working on the best tip pattern. I wanted the entire motor dialed in perfectly. Top of cylinders looked great last I had the heads off for the aluminum swap, maybe 1,000 miles ago. Leakdown test had good numbers across the board. To this day it runs well, but things about the motor annoy me.I won't pull the shortblock apart. If it comes to that, I'd be better off picking up a newer low-mileage F150 5-liter longblock and completely revamping my drivetrain. If you do the math of parting out an existing drivetrain, the swap is only a couple thousand dollars more - with hydroboost, power steering, k-member, and ecu/harness. Just need a pair of exhaust cams and you're well on your way to a 450-horse modern setup.I doubt this engine will have a problem anytime soon - it's just an idle annoyance. Quote Selected
Idle motor noise Reply #5 – December 22, 2016, 10:31:39 AM I am in the process of doing an F150 Coyote motor and 6R80 trans into a 1970 F100 so I understand the cost involved. I have been researching it for over a year now and finished up the calcs for the fuel system to cover the additional hp from the Precision turbo. I was waiting for an aftermarket controller for the trans as I did not want to hack the F150 harness and ECU to defeat the PATS and all the CAN BUS goodies. US Shift has a very slick controller so that sewed up the last part of the driver train for me. Going to use Ford's control pack for the motor as that harness is super simple and the ECU is already flashed with the Coyote software so it can be tuned a lot quicker for the turbo.Another dumb question, the sound is not coming from an accessory is it? Power steering pump, A/C, alternator, etc.? Quote Selected
Idle motor noise Reply #6 – December 23, 2016, 01:32:40 AM Yeah, I love the LKQ f150 motor options. I think the youngest I've seen had around 3,000 miles. I'd likely be going standard FMS control pack, which I've seen tempted to bite in the past at $1100 second hand, unused. May start with a 4r70w since I already have the controller, but ultimately I would want to stick a t56 in there.In the end it's still an expensive swap to get everything properly finished up. Even if the motor is mounted and idling (so you know you have a good used motor), there's a couple thousand more to spend on just supporting hardware to make it more of a road-worthy vehicle. Hence why I'd like to keep the existing engine in there for a few more years!I don't know what else in the engine bay would make that noise. It's surely an up and down noise. Was just hoping for any other ideas. I'll have to check the oil pressure again as I haven't had an external gauge on that since the motor was built. I would think the sound was a rocker arm getting less oil when the pump is spinning slower, and one passage not flowing as much as the others.T he sound sure seemed like it was coming from the lifter valley last time I poked around. But again - the top end has changed a couple times. GT40 to GT40P to TW170, Cobra to GT40 intake, 3 sets of lifters, 19lb, 24lb, and 30lb injectors, two sets of pushrods, 2 sets of rocker arms. Camshaft and rest of shortblock has been a constant. Quote Selected
Idle motor noise Reply #7 – December 23, 2016, 08:25:02 AM Wonder if it is the timing chain? Quote Selected
Idle motor noise Reply #8 – December 23, 2016, 12:59:07 PM Quote from: Aerocoupe;458616Wonder if it is the timing chain?I had thought about that. I want to try getting some steel valve covers and seeing if the sound les a bit. I hate my purple valve covers anyway - you have to think things through. Black with red candy on top turns out gross.Our office is closed next week, so I may spend some time on this, along with finally get my replacement distributor and tfi installed. I'm still on a 29 year old set. An annoying misfire I can feel in the exhaust (and see exhaust flames, open header and tail pipe) at any load and rpm, open and closed loop, cold and hot, has also bugged me forever - the other reason I want a new powerplant. I have too much time and money into trying to solve some annoyances. Since all tests on the longblock appear good, no vacuum leaks, good afr, the other tings that have been a constant have been my wiring harness, ECU, and that distributor. New motor replaces all of that. Quote Selected
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