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clutch chatter after everything warms up.

itsabronco

Full Member
Joined
Jul 27, 2009
Messages
551
Loc.
Banning, CA.
Still chasing clutch gremlins on my '72. Ive put older posts up on here awhile ago but just kinda gave up on it. It works as you would expect it to when its cold, but after it warms up a bit, its almost impossible to take off from a stand still without the shuddering of the whole vehicle. It also works just fine in 4 wheel lo when out in the desert. Its just has a simple no name clutch from NAPA. 2nd one in there by the way...%) First one was thrashed from a brand new, warped flywheel. This one just plain sucks :mad:

Its got a 5.0 EFI engine, 4 spd trans, 33x12.50x15s, 4.09 gears. The old clutch worked great for the last 10 or 12 years on the same things except it was a stock 302 with 3.54 gears. Did the conversion, yes its all done the proper way, I just put a sh#t clutch in it i guess. Didnt learn my lesson the first time...

I have been looking at name brands:
Valeo, Sachs, LUK, and Centerforce. What do you think? The first 3 clutches are close to the same price, $130 to 150, the Centerforce is $310. Prices looked up on Parts Geek.
 

charlesecarter

New Member
Joined
Oct 21, 2006
Messages
120
Loc.
Goochland, VA
I am also interested in this discussion. Mine does the exact same thing and I used the top priced NAPA clutch, which I found was made by Zoom. So, should be a good clutch. It never did this before I changed the clutch, but I figured put the new clutch in while I had the engine out and putting in extra ponies under the hood wouldn't help the older clutch.

Wish I had just put the old one back in.....
 

TBS-POPS

Bronco Guru
Joined
Jun 16, 2007
Messages
1,388
Loc.
valley springs, ca
Ditto on above. flywheels must be resurfaced when new clutch is installed or "chatter" will result. They have started Cryoing brake roters to keep them from warping, I wonder if it would work on a flywheel to keep it from hotspotting and warping???
 

rwill

Sr. Member
Joined
Apr 1, 2010
Messages
522
My exact problem was a bad clutch plate. Bad news I know. The plate had weak spots that would cause it not to engage correctly. Plate and flywheel resurfacing time.
 

Bronco717274

Bronco Guru
Joined
Jan 27, 2008
Messages
1,199
Loc.
Tremont, Ms.
Your wasting your time money and labor if you don't get the flywheel resurfaced. And if you buy a cheap clutch you get a cheap clutch. It will affect preformance and mileage if not done properly. Get a good name brand and be done with it. Use plenty of brake parts cleaner when putting back together any grease weather from your dirty greasy hands or the natural oils from your hands will cause slick spots. If your flywheel has several bluish spots those are hot spots and you can't turn those out it's time for another flywheel. Not what you want to here but true. if you resurface a presure plate your loosing its clamping force.
 
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itsabronco

Full Member
Joined
Jul 27, 2009
Messages
551
Loc.
Banning, CA.
Yeah its all been resurfaced. i know about get what you pay for. Napa said they had LUK clutch kits but they dont know what they have. Thinking gonna go with centerforce.
 

73azbronco

Contributor
Bronco Guru
Joined
Nov 11, 2007
Messages
8,235
Try runout of the flywheel to see if it wobbles on the crank as it turns.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
49,479
What, if anything, have you done with the driveshaft and engine/tranny mounts?
Since you have a new engine, I'm assuming you changed the motor mounts? Tranny mounts too?
What about u-joints? How old are they and what condition? Also, what's the angle of the rear pinion in relationship to the driveshaft centerline?

What I'm getting at is just in case there is something other than replacing another clutch in your near future. I'm thinking that an out of line u-joint could act up when the grease gets warm, where it doesn't when first tried.
And the mounts may soften up when hot. Not likely on good mounts, but old decrepit ones... Could be.

Did you leave any of those mounts loose when you did the last clutch change?
Not likely I know, but had to ask.

Maybe it's a contaminated clutch disc. Ok when cold, but when the oil/stuff heats up and works more at the surface and changes all the friction coefficients, things might change.

Just a few things to throw out there and mull over. Might be way off base, but they came to mind.

Paul
 

bmc69

Contributor
Bronco Guru
Joined
Jun 11, 2004
Messages
11,917
Every time I've dealt with a persistent take-off problem like this - and having verified the clutch and flywheel are all fine - it has been cuased by some combination of:

1. weak/cracked rubber motor mount(s)

2. Rear spring/axle wrap due to distorted leaves in spring pack (or even a cracked one or two..they always crack where clamped so its easy to miss..)

3. Rear spring axle wrap due to rockered spring perches and/or loose u-bolts. Many the spring perches I've rebuilt or replaced for that reason...even the tiniest amount of rocker on the spring mount surfaces of perches and spring wrap is amplified...

4. Rear spring axle wrap just because that's something many EB's "just have no matter what ya try until you throw in the towel and install an anti-wrap bar or bars"
 

bad 68

Full Member
Joined
Jul 1, 2010
Messages
930
Loc.
Northest Washington
I have preached this before on every clutch chatter thread and here I go again!

Clocking the Bel housing. GOOGLE it!

I'm running a McLeod Long style clutch. I installed a SVO Motor sport 351 crate motor. Painted the block before I installed it. Stripped the Bellhousing and painted it before I mated the two.
Brand new McLeod Flywheel, Pressure plate and clutch disc. Brand New NV 3550 Trans behind it all.

Clutch chatter from HELL.

I tried to live with it by taking off in first gear all the time.

Got tired of the shitty performance despite all of my Money and time spent.

Googled Clocking The Bel housing.

Went out and bought a dial indicator and magnetic base. Removed the trans and clutch. Used the dial indicator to check Bell Housing Center. It must be directly inline with the Crank shaft. Makes sense right?
Spec is .007< . I was getting +.012 top to bottom. .009 left to right.

I then stripped all the paint off of the mating surfaces of the block and bell housing until clean bare metal.

Reinstalled bell housing and flywheel and rechecked run out.

.003 was my worst run out side to side and top to bottom was perfectly .001.

Removed bell housing and installed clutch, bell housing and transmission/Tcase, rest of drive train.
ABSOLUTELY NO CLUTCH CHATTER!! Even when taking off up hill in second gear.

You can NOT paint the Machined Mated Surfaces of block and bell housing any more than you would paint any others machined surfaces like block and head, or block and timing cover.
 
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itsabronco

Full Member
Joined
Jul 27, 2009
Messages
551
Loc.
Banning, CA.
Ujoints new, all mounts new, nothing has changed with anything except the engine. I understand evryones questions, but to me, it would do it all the time, not just when its warmed up. I looked up clocking the bellhousing but it dont make sense to me yet because its got the dowel pins that it fits tightly on.

Flywheel brand new, and resurfaced.

I really appreciate everyones input. I will be checking on everything i know, and thanks to you, I have a few more items to check .

I am going to be replacing my lift with a new one soon so i will probably be adding traction bars when i do that. It very well could be axle wrap as a part of the problem because it has an add-a-leaf in the rear springs for the lift from the P.O. The factory springs are still in it. Ive had it for 15 years and who knows how long before that the lift was done.

Keep some ideas coming and I will get into it SOON. Gotta figure out what clutch set to get. Leaning towards a Centerforce.
 

bad 68

Full Member
Joined
Jul 1, 2010
Messages
930
Loc.
Northest Washington
Clocking the belhousing is not just about the dowel pins fitting tight. It's about checking run out with a dial indicator to make sure the input shaft of the transmission is perfectly in line with the crank shaft.

IF you have a stock Ford bell housing it will likely meet run out specs with a Ford block without Off Set dowel pins as long as the machined mating surfaces are spotless.

If the only thing that changed was a New Engine, Did the new block receive a New paint job before the bell housing and engine block were mated together?

The engine block doesn't mate to the bell housing all the way around. Only around the top 2/3rds. That is what cocks the trans down at an angle and throws your clutch face out of alignment.

This is a Machined surface that many over look the importance of measuring for correct tolerance.

There are so many guys that get on this forum to look for advice on Clutch Chatter and then argue as to what their problem may or not be.

Give me the run out specs on your bell housing to crankshaft, and if they are less than .003 I'll quit trying to help you guys with my over bearing attitude.
 
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itsabronco

Full Member
Joined
Jul 27, 2009
Messages
551
Loc.
Banning, CA.
Dont get me wrong bad 68. i completely understand what you are saying. ive just never heard of doing that before. i dont really understand the process thats what i mean when i say it doesnt make sense to me . i will be diggin into it soon. im just looking for all to check because it F@CKING sucks removing the trans on these things!

excuse my french but i only want to do this one more time!!
 

Outlaw Bronco

Jr. Member
Joined
Nov 27, 2011
Messages
153
Loc.
Shenandoah, VA
Due to the tolerances allowed buy the bellhousing mfg's, machining of the block's main bores, dowel pins, flywheel fit of the crank all effects the runout of the register bore to the main bore. The paint will most likely hold the bell from being perpendicular to the crank.

Makes a huge differance in clutch life, performance and shifting the trans. Well worth trouble to do.
 

bad 68

Full Member
Joined
Jul 1, 2010
Messages
930
Loc.
Northest Washington
I have dealt with mild to severe clutch chatter on several Fords.

Pulling transmissions on 4x4s Does Suck!!

If you have clutch chatter these things will almost guarantee a very smooth clutch.

Clean, bare surface between engine block-bell housing-transmission mating surfaces.

Measure center of bell housing off of crankshaft rotation

Brand new quality flywheel or resurfaced flywheel from a quality machine shop.

Properly installed quality clutch disc and pressure plate. I think the Long Style gets a bad rap. Go with Diaphragm style if it's your preference.

Many guys have installed quallity clutch components just to have Chatter Problems. If you don't know if your bellhousing is centered your just waisting your time.
 

nrramse

Sr. Member
Joined
Apr 20, 2008
Messages
522
I had this exact same aggravation for many years. I patiently put in multiple clutches, both 3 finger and diaphram (resurfacing the flywheel each time), and it would drive great for a couple of weeks then back to shuddering - especially in reverse. Happily, when I switched to a NP435 the problem went away.
 
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itsabronco

Full Member
Joined
Jul 27, 2009
Messages
551
Loc.
Banning, CA.
I probably will dive into it next week. I gotta finish power steering up on my other 72 so i can get into the garage. I will definitely be cleaning the mating surfaces on the block and bell housing. I did paint the block so i am sure there is spray on the back of it.

I need directions for checking the runout though. I have no idea what this process involves other than some tool I dont have . Time to google away !
 

bad 68

Full Member
Joined
Jul 1, 2010
Messages
930
Loc.
Northest Washington
The tools you need are a Dial Indicator and Magnetic Base to hold it. Now here's the part where your going to think i'm full of shit:

Harbor Freight. They sell both for under $40 and the indicator is accurate and the mag base is pretty strong. Once you have these tools you will use them for everything from checking shaft endplay to valve lifter preload.

There are a lot of detailed instructions on how to measure that Google can help you find.

I think the NP435 maybe got rid of his clutch chatter due to it's low first and reverse gears.

In a nut shell this is how you measure:
1) get down to the bellhousing
2) pull bellhousing and remove clutch
3) Remove 2 flywheel to crank bolts. This is where your mag base will atatch
4) Reinstall bellhousing
5) Set up dial indicator to slide on inside circle of bellhousing where trans slides into bellhousing
6) take readings at 12 oclock 3, 6 and 9.

If you do this before you remove any paint it will tell you if this is your chatter problem. Then clean the surfaces down to bare metal but not with a grinder. You don't want to remove any metal.

Re install bellhousing and remeasure hopfully you will be within .004 in both directions.
 
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