Topic: possible bad throwout bearing?

[RUGER]

wow...thanks bigmike. i know about the leave it in neutral with the cluth out trick. but the syncros i didn't. thanks bigmike

happy trails
rich *ruger*

[BLACKDOG [OP]]

I didnt know that about the syncros, but I was also taugt properly.  I never leave my truck in gear when stopped

[BLACKDOG [OP]]

Let me make sure I get this, the pilot bearingis not used when the truck is under load, it is only when shifting that the bearing is used  right?  What exactly does the pilot bearing do?  keep the input shaft rotating at speed so that it will go into the next gear? 

Also, what about clutchless shifting?  I knowe how to do it, and I can do it, but is it good for the tranny? 

[BigMike]

the pilot bearingis not used when the truck is under load, it is only when shifting that the bearing is used right?

Its not related to load. If the clutch is disengaged then its not in use. If the clutch is engaged then its in use. Try to think about it this way, when ever the engine speed is varrying from the transmission speed then the pilot bearing is being used. For instance if you are stopped and you have the clutch pedal all the way down: The engine is still turning but the transmission is not.
If the trans the clutch is disengaged then the pilot is just sitting there. Under power, cruising, coasting, even if you are coasting in netural, if the clutch is not in use then neither is the pilot.

What exactly does the pilot bearing do? keep the input shaft rotating at speed so that it will go into the next gear?

[BLACKDOG [OP]]

got it

so what about the clutchles shifting?

[BigMike]

( looks like my masters degree in drawing has paid off )


So look at that above pic. The red area at the end of the transmission input plugs into the pilot bearing that is pressed into the back of the crankshaft.

Not every engine/trans uses a pilot bearing. My 4A-GZE & C52 setup in my MR2 does not use a pilot bearing. At the end of my trans input shaft, there is no little stub.

The pilot bearing just splits the load the Input bearing has when ever you are slipping the clutch. It helps keep the transmission input and the clutch disk in the same place at all times. A Pilot design is much better because it can dramatically increase the life span of the transmission input bearing.

Also, what about clutchless shifting?  I knowe how to do it, and I can do it, but is it good for the tranny?  

If you were to make every shift perfect, it would be good. But in general its bad. But I do it all the time. Since the trans is always connected to the engine, there is no differences in the gear speed to engine speed, so when you try to change gears, if you dont have the engine & gear speed at the same rpm, then the syncro will try to correct it, but since everything is still connected (the clutch is disengaged) the syncros cant do jack squat and so they get squeezed and then as you try to engage the gear, one gear is spinning faster than the previous, which is impossible to engage with a 1:1 shift hub, so it grinds and wastes teeth and puts metal into your oil.

But I do it all the time Just be sure to be consistent and DONT EVER force it. If you do this then you should be so good that you can engage it with just one finger and get it to go into gear. If you put pressure, then you are directly squeezing the syncros up against a piece of metal that is impossible to alter its speed.

BigMike

[BLACKDOG [OP]]

cool  I can do that then, i taught myself on a friends junker, and I still do it everyonce in a while.  Thansk for all the info Mike much appreciated

I have learned so mch overr the past 2 months about my truck than I have in the previous two years, and saved my self a ton of money as well 

Thanks to all

[BLACKDOG [OP]]

gonna be pulling the tranny this weekend, man I wish I had known about this/thought about this when I had the engine out   Anyone have any tips or tricks for pulling the R150F ??

[BigMike]

Sometimes the top two bellhousing 17mm bolts can not only be a real pain to get to, but can require a very strong impact to remove.

Remove those two upper bellhousing bolts first. Once you are ready to remove the trans (after you remove your shift levers, drivelines, wires for 4WD light and reverse, clutch slave cylinder, starter, yadda yadda yadda), put a jack under the crossmember and undo the 8 crossmember bolts at the frame. Then lower the entire transmission and transfercase with your jack about as low as you can. This way you can get a long-ass 1/2" extention onto those upper bellhousing bolts, and with your best torque gun, get those babies outta there. Then jack the trans&tcase back up and remove the other bellhousing bolts. Then just give it a little wiggle and its yours

BigMike

[BLACKDOG [OP]]

Anyone else??   anyhelp is appreciated 

[Willy Mammoth]

  Did you know you can change the clutch on a early Datsun 310 without taking the trans out?   That was a smart designer, I'd like to shake his hand.

Sorry that didn't help any, but it is entertaining.

[BigMike]

Wow, I would like some details on that engineering feat!

[Willy Mammoth]

   Oh well, The 310 built in the late 70's or early 80's was front wheel drive. It had a tranverse engine and transmision. You could take off a cover on top of the bell housing and remove the pressure plate bolts. You took an access panel off the inner fender and remove a few bolts from a housing on the end of bell housing. then remove the input shaft through the access opening. Then you could remove the clutch pressure plate and disk. You only had to turn the wheels all the way to the right. Never even had to jack it up. I did a clutch job on one in about 30 minutes my first time.

[brainlessfool]

yup, that was a sweet car for a clutch job. I worked at a nisson dealer from 81-84. to bad the 310 was mostly junk. saw a few that held together butt most just fell apart.

[79coyotefrg]

blackdog, dude,    always replace the throwout and pilot bearing anytime the tranny is pulled,  clutch disc too if its been awhile

[BLACKDOG [OP]]

but i didnt pull the tranny glen!  


Now you tell me!  

Well, I got the tranny pulled, and the bearings replaced, the pilot bearing was shot!! the throwout seemed good, but I replaced it anyway, not wanting to do this again anytime soon.  The clutch plate and everything have been replaced almost exactly a year ago, so it is fine.

The hardest part was lining up the input shaft into the engine, as Ruger would say, "Its like a monkey f**king a football"