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-   -   Frustrated, discouraged and don't know what to do (https://67-72chevytrucks.com/vboard/showthread.php?t=569719)

derotoreut 03-08-2013 11:03 PM

Frustrated, discouraged and don't know what to do
 
OK I'm at this point where I'm totally lost and don't know what to do any more. Last summer I had a 383 stroker engine built by United Racing Engines out of Phoenix. After installing the engine I found out I had a noise that I couldn't identify. After trying everything under the sun, (and I mean everything) I couldn't identify the noise. All this time I kept URE in the loop on what was being tried. Unfortunately, no luck. URE suggested that I pull the engine and send it back to them to go over and rebuild as need be. By the way... through all of this they have been great. Anyway, they totally rebuilt the engine and returned it to me just before Christmas. Now after installing the engine I found out again that I have this same unidentifiable noise. After everything I tried I thought this noise was coming from the engine. I was so excited to get this reinstalled just to find out I have the same problem. Now I'm not sure if the noise is coming from the engine or somewhere else. I have no clue what to do any more. I thought I did everything I could the first time. I've had it.

rsavage 03-08-2013 11:19 PM

Re: Frustrated, discouraged and don't know what to do
 
Dan,
Sorry to hear of your problem. Couldn't be a cracked flex plate could it? Maybe using a redneck stethoscope (piece of wooden broom handle held up against your ear and against various areas of engine and transmission) could isolate the noise? Hope it is something simple.
Rick

71swb4x4 03-08-2013 11:22 PM

Re: Frustrated, discouraged and don't know what to do
 
Have you taken the truck to a mechanic? Sometimes you get stuck thinking one thing, and a fresh sets of eyes (or ears) can find the true problem.

Shyguy 03-08-2013 11:31 PM

Re: Frustrated, discouraged and don't know what to do
 
Just throwing out ideas. I have had a noise before similar that came from a belt with a small chunk out of it.

I had a fan blade ticking on a shroud. Also my son does not run dust covers at the flywheel because he said he has had a noise coming from it.

I have a ticking noise coming from the engine in one of my vehicles and it is a small exhaust gasket leak.

72MARIO 03-08-2013 11:44 PM

Re: Frustrated, discouraged and don't know what to do
 
If it makes you feel any better I paid 4300 for my 383 and less that a year old the block cracked just above the oil pan rail near the starter..

buckskins4ever 03-08-2013 11:46 PM

Re: Frustrated, discouraged and don't know what to do
 
Sorry to hear youre havin probs. first question I would have about or from URE is if they ran the motor on the stand or just built to specs and shipped it off. My builder does a stand run up to 5k rpm just to break in the engine, then he will even fine tune valve adjust before we dyno it. does the noise louder or faster with acceleration? Is the noise at idle, in gear, driving? Is it a knock, tick, slap, thud, what exactly does it sound like.
Funny thing is I have seen water pumps brand new out of the box with a bad bearing and tick louder than a bad lifter......and thats was on a brand new motor.

70shortfleet 03-08-2013 11:46 PM

Re: Frustrated, discouraged and don't know what to do
 
Did URE find anything wrong with the engine when they rebuilt it? Is the noise when it is sitting still or moving?

midniteblues 03-09-2013 12:18 AM

Re: Frustrated, discouraged and don't know what to do
 
I can relate your frustration but maybe you could do a video with your "noise" too help us understand what your dealing with engines can make all kinds of sounds when you dont want them too

derotoreut 03-09-2013 12:20 AM

Re: Frustrated, discouraged and don't know what to do
 
First of all the noise is only evident when the truck is under load. It will not make the noise when it's idling or revved up when sitting still. When given throttle under load it is like a knocking, tapping kind of noise. That's one of the reasons why it's so hared to find, because it has to be moving and the throttle stepped on (but not even stepped on that hard).

I have investigated exhaust leaks at the headers and collectors. I'm sure there are none. I also looked at the flex plate and know it is not cracked. I checked the torque converter bolts to make sure they were tight. This go-around I even replaced the torque converter. I thought maybe it was something from the accessories like maybe A/C compressor, alternator, PS pump or even water pump. I ended up removing my serpentine belt just for a quick ride to find out it wasn't anything related to the front end belt. I looked into the timing because I thought maybe it was detonation. My timing was all good. I even checked the spark plug wire resistance and changed out the wires and plugs.

When URE built the engine it was run on the dyno and fully broken in when received. Upon receipt this engine should be able to be run right up to 6000 RPM with no problem. I have curves, graph and video of the dyno from the original build and the second rebuild. The only thing they were able to find was slight play in the wrist pins. They changed out the entire rotating assembly with new crankshaft and pistons.

When I had my original 305 engine installed, it did not make this kind of noise. That's why I thought it was something related to the URE engine. The only other thing I did was to install a cast aluminum deep transmission pan, with filter extension.

derotoreut 03-09-2013 12:29 AM

Re: Frustrated, discouraged and don't know what to do
 
Quote:

Originally Posted by rsavage (Post 5935549)
Dan,
Sorry to hear of your problem. Couldn't be a cracked flex plate could it? Maybe using a redneck stethoscope (piece of wooden broom handle held up against your ear and against various areas of engine and transmission) could isolate the noise? Hope it is something simple.
Rick

Hey Rick,
Thanks for your concern. I really checked out the flex plate good to make sure it was fine. I've heard that a cracked flex plate could cause a problem like this. It is a brand new flex plate, but I still checked it out.

BTW... What is this '65 Fairlane?

derotoreut 03-09-2013 12:34 AM

Re: Frustrated, discouraged and don't know what to do
 
Quote:

Originally Posted by midniteblues (Post 5935679)
I can relate your frustration but maybe you could do a video with your "noise" too help us understand what your dealing with engines can make all kinds of sounds when you dont want them too

You know it's funny that you mention this. When this happened the first time, I secured my IPhone in the engine compartment in order to get audio of the noise. I sent the audio by email to URE telling them at what point in time to listen for the noise. I will see if I can find it and attach it here.

derotoreut 03-09-2013 12:57 AM

Re: Frustrated, discouraged and don't know what to do
 
I don't know how to post the videos, so I provided links to them. It's a Quick Time video. Hopefully it works.

On the first video you can hear the engine noise at the following amount of time into the video:
https://www.sugarsync.com/pf/D7308442_4115878_485760
19 sec - 21 sec mark
22 sec - 24 sec mark
33 sec - 37 sec mark
47 sec - 52 sec mark

On this second video you can hear the engine noise at the following amount of time into the video:
https://www.sugarsync.com/pf/D7308442_4115878_485777
5 sec - 6 sec mark (lightly)
31 sec - 37 sec mark (fairly strong and then tapers off)
46 sec - 50 sec mark

Boog 03-09-2013 01:09 AM

Re: Frustrated, discouraged and don't know what to do
 
So you know the engine isn't torquing over and making the exhaust system bump the frame? You might try backing the timing down a few degrees and run it to eliminate a timing issue. You run a good grade of gas?
I once had an AC fuel pump peck hard like a loose rocker. New one took care of that.

oklalawnboy 03-09-2013 02:05 AM

Re: Frustrated, discouraged and don't know what to do
 
I'm with Boog on the grade of gas. What compression ratio is the 383? Extreme but my 383 is 13 to 1 and has to have 110 octane to not ping rattle knock etc.

Sammy 03-09-2013 05:53 AM

Re: Frustrated, discouraged and don't know what to do
 
Just from reading this post. And the way sound travels. After checking the gas ping issue out. I would look at tranny and drive shaft noises as the possible cause. Has to be something that was removed and appeared after the swap. Engine issues I feel are almost ruled out. Just my wild guess!

Bishops Trucks 03-09-2013 07:07 AM

Re: Frustrated, discouraged and don't know what to do
 
Could be a universal joint. they do make some weird noises sometimes.

derotoreut 03-09-2013 09:42 AM

Re: Frustrated, discouraged and don't know what to do
 
Quote:

Originally Posted by oklalawnboy (Post 5935863)
I'm with Boog on the grade of gas. What compression ratio is the 383? Extreme but my 383 is 13 to 1 and has to have 110 octane to not ping rattle knock etc.

The grade of gas used was fresh premium 93 octane. The engine was designed for 9.9:1 compression ratio to run on 91 octane pump gas. I did not want a high compression ratio engine that required more octane than pump gas. I didn't want to have detonation issues. If I went 10.3:1 would require 93 octane or 11:1 would need 110 octane racing fuel. I really don't believe I have a bad fuel or detonation/timing issue.

formikaus 03-09-2013 09:46 AM

Re: Frustrated, discouraged and don't know what to do
 
Have you checked all of your vacuum?

I would check the gas also. When I installed the crate 350 in my old stepside, it would always ping as I accelerated heavy, and when they started adding " up to 10% ethanol" I had to run premium grade.

The weird thing is in the second video, it sounds like the noise does not increase with the RPM's???

I really hope you find out the problem, a noisy engine is as bad as door glass without weather stripping.....will drive you bonkers.

Good luck!

formikaus 03-09-2013 10:06 AM

Re: Frustrated, discouraged and don't know what to do
 
I just asked a buddy about this. He told me that when he installed the 6.0 in his he used the stock flywheel and wound up cracking it between the bolts, got another flywheel and warped it and eventually upgraded to a performance flywheel.............. HE SAIS he had the same noise and problem. It would sound fine when idling and reving in park, but once he put it under a load, same noise as yours..... did you use the stock flywheel?

hope this helps!

derotoreut 03-09-2013 10:32 AM

Re: Frustrated, discouraged and don't know what to do
 
Quote:

Originally Posted by formikaus (Post 5936079)
I just asked a buddy about this. He told me that when he installed the 6.0 in his he used the stock flywheel and wound up cracking it between the bolts, got another flywheel and warped it and eventually upgraded to a performance flywheel.............. HE SAIS he had the same noise and problem. It would sound fine when idling and reving in park, but once he put it under a load, same noise as yours..... did you use the stock flywheel?

hope this helps!

Thanks. I have heard the same thing. However, my engine has a brand new SFI Precision flex plate. I also heard that loose torque converter bolts could cause this too. I'm pretty sure I can rule these out.

BADPURPLE70CHEVY 03-09-2013 11:08 AM

Re: Frustrated, discouraged and don't know what to do
 
Man i know it's aggravating i have been in a similar spot before. I agree that maybe a fresh set of eyes and ears could give new perspective. Hang in there though and take a deep breath you will find it.:)

steves1967 03-09-2013 11:28 AM

Re: Frustrated, discouraged and don't know what to do
 
When they dyno'ed the engine did they use the same carb and distributor that you are using? I've had an MSD distributor with alot of shaft play and it was causing all kinds of noises. It finally just clearanced itself. I here a slight "whistle" noise- could it be a bad gasket on the carb?

eightbanger 03-09-2013 12:34 PM

Re: Frustrated, discouraged and don't know what to do
 
I installed a new damper on mine, and at the same time I renewed the timing chain cover and fitted a new chrome timing indicator also....on idle the engine was fine but when under load it made a similar noise to your's, turned out that the damper would rub on the timing indicator. I was really glad to find it because up until that point I could not understand what that dam noise was.....hope you pin it down.

budman k20 03-09-2013 08:57 PM

Re: Frustrated, discouraged and don't know what to do
 
I remember having to clearance my stock oil pan with a ballpeen hammer when I built my 383. There is not much rod bolt clearance right where the pan bolts to the block. This is just a guess...but I would bet the (thick) cast aluminum pan is being hit by the rod bolts.

derotoreut 03-09-2013 09:03 PM

Re: Frustrated, discouraged and don't know what to do
 
Quote:

Originally Posted by steves1967 (Post 5936195)
When they dyno'ed the engine did they use the same carb and distributor that you are using? I've had an MSD distributor with alot of shaft play and it was causing all kinds of noises. It finally just clearanced itself. I here a slight "whistle" noise- could it be a bad gasket on the carb?

Yes they used the actual carb and distributor for the dyno. The carb is a Quick Fuel 780 CFM, and distributor is GM Performance HEI. All new.


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