T5 Throwout bearing failure

jrvariel48

jrvariel48

Well-known member
Sorry I posted this in another thread, but thought I should post it separately.
Car is a 35 coupe with a 46 flathead and T5 trans.
Is there a throwout bearing depth to be concerned with? I have a Fort Wayne 9" clutch and pressure plate with a Cornhuskers bellhousing and slave cylinder set up. I also installed the so called heavy duty, American made throwout bearing from Macs. This has been in my coupe for about 1000 miles. The other day I noticed that when I pushed the clutch in and put the trans in 1st gear, I get a sound when I put the rpm up a little. It's not a high pitched squeal but it's getting worse. Is my bearing shot already? If so, what causes this premature failure? This is why I asked about a depth for the bearing to be off the pressure plate fingers. Any info would be great!
Thanks, Joe
 
You want about a 1/10" clearance between the T/O bearing and PP fingers when the pedal is fully released.
 
do you have a return spring on the throw out collor as was as in the stock application? when i first did my T5 swap there was no provision for a return spring and it caused the bearing not to return far enough and it continually rode on the pressure plate forks and wore several out until i figured out how to mount a return spring and keep the T.O. bearing back away from the pressure plate..
 
I do provide the return spring in my kit but just instructions how to mount it. Many of my customers use a simple self tapping hook for the spring. Maybe I will have to start including one?
 
If it does not make noise until you put it in gear and stop the input shaft you most likely have a pilot bearing failing. A throw out bearing will make noise anytime the pedal is depressed. Neutral or in gear should not make a difference.
 
V8 Bob said:
You want about a 1/10" clearance between the T/O bearing and PP fingers when the pedal is fully released.
Click to expand...

Thanks Bob. Is there a way to check that with the trans installed?
Will I be able to see if I remove the bottom bellhousing cover?
 
donald1950 said:
do you have a return spring on the throw out collor as was as in the stock application? when i first did my T5 swap there was no provision for a return spring and it caused the bearing not to return far enough and it continually rode on the pressure plate forks and wore several out until i figured out how to mount a return spring and keep the T.O. bearing back away from the pressure plate..
Click to expand...

Yes, I did install a spring. If I remember correctly, it was a stock style spring.
 
Krylon32 said:
I do provide the return spring in my kit but just instructions how to mount it. Many of my customers use a simple self tapping hook for the spring. Maybe I will have to start including one?
Click to expand...

I think I made a part to attach the spring. It mounted under the bolts of the input bearing retainer. I wish I took pictures!
 
37 Cab said:
If it does not make noise until you put it in gear and stop the input shaft you most likely have a pilot bearing failing. A throw out bearing will make noise anytime the pedal is depressed. Neutral or in gear should not make a difference.
Click to expand...

I'll have to check that. When I had the car out on Thursday, it was happening with the clutch depressed, in gear and revving the motor a little. I didn't try it out of gear.
Thanks
 
Just started the car to try to figure out the noise I'm hearing and this is what I have.
No noise with car idling with the clutch in or out. It makes the noise when i push the clutch in and put the car in gear. This doesn't happen every time, but it did make the noise in 1st, 2nd and reverse. I didn't try the other gears. As soon as I start to release the clutch the sound goes away and as far as I can tell, it only happens in gear.
So, is this the pilot bearing as 37 Cab suggested or the throwout bearing?
Thanks, Joe
 
jrvariel48 said:
Just started the car to try to figure out the noise I'm hearing and this is what I have.
No noise with car idling with the clutch in or out. It makes the noise when i push the clutch in and put the car in gear. This doesn't happen every time, but it did make the noise in 1st, 2nd and reverse. I didn't try the other gears. As soon as I start to release the clutch the sound goes away and as far as I can tell, it only happens in gear.
So, is this the pilot bearing as 37 Cab suggested or the throwout bearing?
Thanks, Joe
Click to expand...



Joe from what I have seen if you have a pilot bearing failure you will not be able to get the car in gear. The input shaft will move around a lot and the sound will be unforgetable. In my roadster at times I will hear a slight noise from the throwout bearing which is a USA bearing. I hear a sound when the bearing is first touching the fingers on the presure plate the sound is gone when the bearing is pushing on the fingers so I can shift gears.

Ronnieroadster
 
Ronnieroadster said:
Joe from what I have seen if you have a pilot bearing failure you will not be able to get the car in gear. The input shaft will move around a lot and the sound will be unforgetable. In my roadster at times I will hear a slight noise from the throwout bearing which is a USA bearing. I hear a sound when the bearing is first touching the fingers on the presure plate the sound is gone when the bearing is pushing on the fingers so I can shift gears.

Ronnieroadster
Click to expand...

Thanks Ronnie. I can say I noticed it's been a little hard to get the car in gear lately. Regardless, it looks like the trans is coming out. I'd like to why it failed in such a short period of time!
 
No idea how valid it is, but Rumbel Seat claimed that later throwout bearings were not greased properly and provide his solution. I'll see if I can find it and post it.
 

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Here is Rumbleseats lubrication procedure for the throwout bearing that
JSeery mentioned.

THROW-OUT BEARING LUBRICATION: These used to come packed with a relatively​
heavy high-temp quality grease. Then manufacturers went to a cheap thin grease​
and not much of it. Consequently, bearings no longer last. The cheap grease​
thins from the high temperatures generated in the clutch area and is soon slung​
out of the throw-out bearing. This not only causes the bearing to run relatively​
dry, it can also cause grease to get on the clutch and flywheel engagement​
surfaces which promotes clutch chatter and erratic engagement. One of the added​
benefits(?) is you get to listen to the throw-out bearing let out a blood​
curdling howl on cold days and in front of your buddies. Neat! While rotating​
the bearing slowly you can feel any bearing roughness. New throw-out bearings​
are lucky to last 15,000 to 20,000 miles before they start their howling act.​
(From rodnut: There are two or three different grades of throwout bearings.)​
A cure I use is to grease them myself .... new and used! These can be greased​
without much effort. I wash the new or used bearing in solvent until I’m certain​
all of the cheap grease used by the manufacturer is gone. Dry it without​
spinning it (low heat or compressed air). Drill a single 1/8" hole on the outer​
edge of the bearing (not in the engagement surface nor in the outer bearing​
race). This is pretty hard and a good bit is needed. Then I use a needle type​
U-joint grease zerk adapter and give it TWO shots of high temp grease. Rotate​
the bearing half way around and give it TWO more shots of grease. That’s all​
the grease it’ll need for well past 50,000 miles. Rotate the bearing several​
times to disperse the grease. I plug the 1/8" hole with a tiny sheet metal screw​
and some red Loctite or solder it shut. Either works. In my Ranchero, I’ve got​
over 200,000 miles on the same throw-out bearing using this method.... and this​
is after it first howled.
 
Can anyone comment on their likes or dislikes of a needle bearing pilot as compared to a bronze pilot?
Thanks Joe
 
Back to Rumble Seats advice:

PILOT BEARINGS: These provide needed support for the front of the
transmission’s main drive gear. It primarily operates only during engagement and dis-engagement of the clutch. When the pilot bearing becomes worn, it permits the main drive gear to jump up and down in the flywheel, the throwout bearing,and the clutch disc. Not a good thing. This is certain to promote clutch chatter and erratic clutch operation. (Ever wonder what the thrust bearing on the engine crankshaft is subjected to during clutch chatter? Scary!) There are two types of pilots used in the flathead.... bushing and bearing.

Bushing type: These are usually made from “Oilite” (a trade name for porous bronze that is impregnated with oil) and are simply called bronze bushings. Oilite wears fairly fast due to it’s softness and porosity. Ford specifies a maximum wear of 0.006". It’s not uncommon to find some worn as much as 0.080"-0.100"! Many have been beat on so long they’ve become egg shaped. When installing a bronze bushing, lube it with a very thin film of high-temp grease on the inside of it’s bore. Rule of thumb I use is to replace the bushing whenever I am looking at one.

Bearing type: These replace the bronze bushings. Because bearings are made of quality hardened steel they last a long time. Most are a sealed type bearing and come with a little cheap low-temp grease. Generally this thin grease is slung out in to the clutch area the first time it’s used. A cure I use is to remove the soft neoprene type seal on one side of the bearing using a sharp pick tool. I’m careful to not damage the seal since I’ll re-use it. Clean the bearing with solvent and dry it with air and/or heat. I don’t spin it with air since it’ll quickly ruin the bearings and races due to heat generation. I work some (don’t pack it since it’ll just sling it off) high-temp thick grease into the bearing (I use Lubriplate #70 which is intended for wheel bearings, but it’s no longer available.). Reinstall the seal and install the bearing. I do this to every new pilot bearing I put in (OHV and FH). Most bearings treated this way last nearly 100,000 miles. Otherwise the cheap grease they come with is gone quickly and the bearing is soon galled and junk. I prefer bearings over bushings since I’m lazy and don’t want to work on things much anymore.
 
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