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rpm drop noise with clutch engagement

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woodnbronze24

10+ Year Contributor
146
0
Mar 14, 2009
Flint, Michigan
Just recently built my motor after a rod bearing failure. The bottom end was professionally machined, balanced, and assembled. I have almost 700 miles on it and noticed right from the start that when I pushed the clutch (act 2600 with a street disc on an act flywheel) in, my rpms drop a lot. I also noticed today a ticking sound with any clutch pressure. The speed of the ticking increases with rpms. The problem has gotten a bit worse within the last 50 miles. Ever since the build I noticed that that trans (TRE) shifted really notchy. I was attempting to diagnose it today and I was under the car while it was running and noticed that the end of the clutch for was moving probably 1/16 of an inch side to side. Not good... do I have a bad input shaft/bearings? I called the machine shop and they said my crank was pretty tight and they highly doubted that it was walking. I have also noticed that when I push the clutch in while my car is off, the clutch creeks in 2-3 spots in the throw of the clutch and it can be felt through the pedal. Also, when the trans was off, I saw that the inside of the bell housing was a little more dirty than I thought it should be. There wasnt just dust, it had oil in there. Not a ton, but some.


Any idears?
 
I would recommend pulling the transmission as well as pulling the oil pan and checking the crank for thrust play. There is a bearing going bad somewhere either in the transmission or the engine thrust bearing.
 
You can check crank end play with the pan and tranny on. You just need a cheap dial bore indicator from harbor freight. From there you need to put a foot long 2x4 up against the crank pulley and smack it what a hammer. Than you will mount the dial bore and zero it out on the crank pulley. With someone watching the gauge someone else push the clutch. This has to be engine related. If it were tranny related than it would happen with the clutch depressed, not pressed. When the clutch pressed the tranny is completely disengaged.

Also ask the machine shop if they replaced the press in oil jets when they did the bottom end. IF not than they should be held responsible for any possible damage.
 
Just recently built my motor after a rod bearing failure. The bottom end was professionally machined, balanced, and assembled. I have almost 700 miles on it and noticed right from the start that when I pushed the clutch (act 2600 with a street disc on an act flywheel) in, my rpms drop a lot. I also noticed today a ticking sound with any clutch pressure. The speed of the ticking increases with rpms. The problem has gotten a bit worse within the last 50 miles. Ever since the build I noticed that that trans (TRE) shifted really notchy. I was attempting to diagnose it today and I was under the car while it was running and noticed that the end of the clutch for was moving probably 1/16 of an inch side to side. Not good... do I have a bad input shaft/bearings? I called the machine shop and they said my crank was pretty tight and they highly doubted that it was walking. I have also noticed that when I push the clutch in while my car is off, the clutch creeks in 2-3 spots in the throw of the clutch and it can be felt through the pedal. Also, when the trans was off, I saw that the inside of the bell housing was a little more dirty than I thought it should be. There wasnt just dust, it had oil in there. Not a ton, but some.


Any idears?

I had a similar problem.

It turned out that my clutch throw was too long due to a pivot ball shim (I didn't know about).

This caused the pressure plate spring fingers to make contact with the clutch disc springs (the 4 small yellow ones in the disc itself).

I had the same symptoms. When the clutch was disengaged (clutch pedal down) I was dropping about 200 RPMs. I also had ticking sounds and vibrations in the pedal at the bottom of the clutch pedal travel.

This went on for a while until the fingers gave out and broke.

Pictures here-> http://www.dsmtuners.com/forums/drivetrain-tech/351015-act-failed-help-diagnose-warranty-pics.html

If you look at the pictures of the clutch disk, you can see how the 4 yellow springs are worn out on the side facing the pressure plate.

I'm not saying this is your problem as well but..... your throw may be too long due to either:

1. a pivot ball shim (by you or someone else)
2. mis adjusted clutch
3. missing spacer plate between the engine and tranny (not sure of the exact name of that plate)
4. incorrect step height on flywheel (or warpgage)
5. anything I've forgotten

You'll have to check the clutch disk springs for signs of wear(see my pictures). If there is no wear then it's probably crank walk.

Good luck, Tom.

EDIT: Check crank end play as well, it's quick to do.
 
Tom, I wish your luck came to me.

I have .025" of crank end play.
 
What's the best angle at approaching the machine shop that did my bottom end to get this worked out?
 
Tell them it's ####ed. Ask if they replaced the oil jets in the block. If not than that is what is causing the lack of oil in the thrust bearing. Regardless they owe you a crank and a set of bearings, and anything else that is damaged.
 
Updates? I agree that the shop should foot the bill. 700miles is well within "warranty" and they should have known if it was a ticking time bomb - which leads me to believe it was poor machining/assembly.
Do these guys do 4g63's or did you make them.. ?
 
The only update is that ive decided to part it out. I havnt torn it down or taken it back to them yet. I don't have the $ to replace all of the gaskets/oil/coolant etc again and I especially don't have the time. I'm just really discouraged over this and it is terrible that this shop has essentially forced me to get rid of my car
 
Wait, so instead of getting the shop to pay for all those things, or at least trying, you're just going to quit?

Kinda sounds like getting into a fender bender and instead of calling up your insurance you just throw in the towel. No?

Then again... if your avatar is current..
 
There's no way there going to buy me new gaskets. They only assembled the shortblock. If they do, maybe I'll find another roller in better shape. Even then, I wouldn't trust the engine after they messed it up the first time. This is my dd, or, was my dd
 
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