I blew the motor in my 04 C5 and I had a new 415 stroker installed and a new monster stage 3 twin disc clutch. I decided to leave the blower off until after the break in. On the very first start up it was runing beautiful. He let run 5 min & then shut it off to change the oil. My installer called me to come over for the initial start up, so I was there. After he shut it down & the motor made a terrible metal screaching sound the last couple of hundred rpm's before it stopped. It was similar to disc breaks with no pad left coming to a stop. He was data logging & check the oil pressure and it was at 52 psi. I then started again with the belt off and the clutch pedal pressed down, so he could listen to see if it was one of the accessories or pulleys. It still made the sound, but not as intense. At that point I was afraid of doing more damage & stopped. Then 2 days later I had a friend who had experience in engine building come by to take a listen. I started it 3 times and it never made the sound & it ran great. At first my friend said from my description he thought it might be a cracked ring, but since it didn't make the sound when he was there he said it most likely isn't a ring because they don't go away. Does anybody have any ideas what it might be or what I should do. I don't want to damage the engine, but the thought of paying another $1500 to have the motor pulled isn't a very happy thought either and that doesn't include tearing it down to look for the problem. Don't get me wrong if that's what needs to be done, then I will, but hoping somebody had another alternative. Thanks in advance

 

what did the "break in" oil look like when ya'll changed it?

Cut open the filter?

 

Run 5 minutes and change oil ??????????????

 

First of all, if I were present to hear and see the start up of a new motor in my car and heard that type of metallic screeching or grinding , I'm not paying another cent until the problem is diagnosed, explained, and repaired. I think most, if not all other guys who have paid pretty 'Good' money for any service and/or engine mods will concur. This is a 'real' moment of knowing who you are working with and the backing up of their 'warranty' on the work performed for you !! $$$$$$$$$$$$$$$$$$$$
Jus Say'n !!

 

After the 5 min if run time, he changed the oil. I wss present for this also. He took the oil filter and strained thru a coffee filter to look any metal. We didn't see any thing to cause concern. There was just minimal micro metal dust particles. The installer even said that it was cleaner than a lot of engines he's done in the past. He then took the oil filter apart to inspect for metal inside the filter paper and again it look clean. At this point he said the engine would have to come back out and gone thru to see what happened.

As far as asking him to stand behind his work, he has no problem in doing that, but since all I did was ask him to install the motor & clutch, not actually build the motor. I'm not sure he is responsible for it. I had the motor built somewhere else & getting them to stand behind a performance engine is not the easiest thing to do. My installer did exactly what I paid him to do.
Do you guys think I should put a belt back on it & start it. Let it get to operating temperature to see if it makes the noise again or should I let it be, so I don't do anymore damage to it. It's just that if the problem had worked itself out I hate to pay all that money to be told it's fine. Thanks everyone.

 

Ask the engine builder ????

 

I've talked to the engine builder also which happens to be in another state, but he did say if there is a obvious parts failure for me to call him back. I already know how that will go though. He'll Raddle off a bunch reason for not covering it. If I need to I plan to try and get him to cover st least some of it, but I'm hoping it worked it self out if that's even possible.Althougi most problems of this nature don't really go away,

 

Hopefully it isn't your engine, I would think if somethings wrong with the engine it would be a constant noise and not at the last few revolutions when shut down. Your guy that did the installation is at least taking a admiral stand on his work, and when I keep thinking about your noise issue, I am wondering if it could be a drive train alignment issue, i.e., flywheel, clutch, starter, or pressure plate. If that is the issue then that certainly falls on the installer. Hope you find the cause to be minor in nature. Good luck brother !!

 

I put the belt back on it and started it up. It runs a little ruff b/c he didn't put the base tune on it yet. I let it get up to operating temperature plus a, couple more min. Then shut it down and there was no sign of the noise. I went thru this process 4 more times to see if heat would make the sound come back and it did fine everything. So do you guys think it was just a weird initial start sound or is there still a, problem. I don't want to damage the motor anymore, so if you think I should stop messing around with let me know. Or should I have the guy put the base tune on it and start breaking it in. Thanks for the help guys.

 

I was thinking that it might be in the drive train also. I need to double check, but if the Monster stage 3 clutch has semi-metallic clutch pad, then it might be able to make a noise like what we heard. I just wonder that maybe because it was a brand new clutch that maybe it made the noise.
I have started the motor and let it get up to operating temperature then shut it down. There was no sign of the sound.
What would you guys recommend?
Do you think it I should start the break in?
Or should I not be starting it anymore because it could be doing more harm to the engine
As much as I want to drive it and get the engine broke in. I don't want to do anymore damage to it. I'm just not sure what I should do.

thanks again for all the help everyone.

 

sounds like a clearance issue of the flywheel clutch assembly, may be hanging up on the bellhousing

 

As said before, if it turns out to be drive train issue's it rests on the installer to repair. If after the removal and inspection of clutch, pressure plate, and flywheel and nothing is found wrong with those components, then you might owe the installer some additional $$$$. Then the burden of proof shifts back to the engine builder to stand behind his work. Or, you do the no-no and drive it (not recommended). Again, I hope you find the problem and it is something stupid, like a wrong bolt 'length' issue. Since you have done more start ups and don't hear the noise it might be that whatever it is made it's own clearance !! Good luck again !!

 

I wanted to give you guys an update on what I've found out. I took a friend over who is retired now, but in his day he was an engine builder and drag racer and worked for a Chevy dealership as a Automotive tech for 8 years before going on his own. I started it let it warm up and shut it down and again no noise. He said lets put a load on the engine to see if the sound is in the clutch area. I put in gear pulled forward out of the garage. Then shut it down and no noise. Then when I started it and tried to put in reverse it just would not slip into reverse until he said shut it down and I'm going to push you backwards and it just went in reverse that way. So he said the sound most likely came from the drive train. He said that its probably the clutch just needs adjustment. The new clutch has a thicker pad than the original and its to tight. He thinks it was so close on the first couple of start ups that it was just barely rubbing when the motor shut down making the sound. then after a couple of startups it wore down.
If that happened I wonder if it damaged the clutch or pressure plate.
I called the installer and told him what was going on and he said to bring it back to let him adjust the clutch and he would make sure the base tune was safe for it to break in. I'm hoping it all works out. Thanks for all the support guys.

 

Fingers crossed for you that the fix could be a lot less than many of us thought.