BCM Community

Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Melbo on September 12, 2007, 06:36:15 PM

Title: Engaging a Spicer
Post by: Melbo on September 12, 2007, 06:36:15 PM
I have been having a ball driving the bus from New Mexico back and forth across Kansas about three times this summer. Everything has been running just fine and nothing has been problematic until this last trip.  When I go to put the tranny in first gear the gears are spinning too fast and no matter how long I hold the clutch in they never slow down.  Once I am moving it is not a problem as I don't use the clutch while driving just for stopping at lights and signs. To get home from this last trip I just shut her down and put in gear and then start it up let the clutch out and go from there. I'm not sure what is different now than before but it really bugs me. At first I thought it was an adjustment but the clutch doesn't engage until it is about 3 or 4 inches up in a 6 inch travel so I wouldn't know how to adjust that.  Any information you can give or ideas of what to do would be appreciated.

Melbo
Title: Re: Engaging a Spicer
Post by: compedgemarine on September 12, 2007, 07:12:46 PM
not real familiar with your tanny but on my big truck as you pushed the clutch in it disengaged the clutch then it allowed the clutch to drag the input shaft so it would engage. if it was out of adjustment then it would engage that part and it was a pain to get it into gear. I would think any shop that works on big trucks could tell you how to adjust it.
hope that helps
steve
Title: Re: Engaging a Spicer
Post by: Homegrowndiesel on September 12, 2007, 09:14:04 PM
Check The 40 weight oil in it. If the countershaft is not in the oil it spins pretty easy (for awhile)
Title: Re: Engaging a Spicer
Post by: TomC on September 13, 2007, 12:00:45 AM
On truck clutches they have a clutch brake.  When you push the clutch pedal down hard, the brake stops the transmission from spinning so you can get the trans in gear without grinding.  You have to adjust the clutch and the clutch brake separately.  I believe you first adjust the clutch then the clutch brake.  But-not all clutches have a clutch brake.  It sounds like you might have a dragging clutch which might mean a broken piece of friction plate the prevents the clutch from disengaging completely.  Good Luck, TomC
Title: Re: Engaging a Spicer
Post by: RJ on September 13, 2007, 12:10:15 AM
Steve & TomC -

No clutch brake on an MCI.


Melbo -

Proper procedure for adjusting the clutch is outlined in the shop manual. 

In the meantime, with the clutch in, try bumping the gearshift into 3rd or 4th, then slipping it over into 1st.  Common trick with the wet-clutch GMCs.

FWIW & HTH. . .

;)
Title: Re: Engaging a Spicer
Post by: FloridaCliff on September 13, 2007, 05:36:01 AM
Quote from: Russ on September 13, 2007, 12:10:15 AM
In the meantime, with the clutch in, try bumping the gearshift into 3rd or 4th, then slipping it over into 1st.  Common trick with the wet-clutch GMCs. ;)

And it works every tiime.


Russ, 

Thanks for all your tips and tricks.

They have made me a much better shifter on these Spicers.

One little trick I have been using is tap the throttle just before I push it in the next gear, I am single clutcher, it works great for us "I don't want to double clutch dudes"   :P  Even with an air throttle.

Cliff

Title: Re: Engaging a Spicer
Post by: prevost82 on September 13, 2007, 10:14:02 AM
I've got a clutch brake on mine.
Ron
Title: Re: Engaging a Spicer
Post by: lostagain on September 13, 2007, 11:41:54 AM
Maybe you have a clutch brake, maybe not. Checking the clutch adjustment would be the first thing to do.

Title: Re: Engaging a Spicer
Post by: gus on September 13, 2007, 01:23:26 PM
I have the same problem with my 4104 four speed. I can get it into first only upon the first start of the day, after that I have to shut down the engine or get it rolling slightly.

It is no easier to get into 3-4 as first.

When I tighten the clutch a bit it helps for a while but soon goes back.

Adjusting your clutch will help if your linkage is in decent shape, otherwise it is an exercise in frustration.

No clutch brakes on these old Spicers that I know of, would be really nice to have one.
Title: Re: Engaging a Spicer
Post by: HB of CJ on September 13, 2007, 01:56:02 PM
Hello Melbo,

Try pushing the clutch all the way to the floor to see if it slows down the tranny.  If it does not work, then probably you do not have a clutch brake.  Neat gadgets, but not all manuals had them.

If your Spicer still refuses to co-operate, (pun) then you probably but not necessarily need just a slight clutch adjustment.  Lots of little small things can cause a clutch to slightly hang up.

Try a trick I have used since I too lazy to adjust my clutch.  Coming up to a complete stop where you will be sitting more than 30 seconds, shift to neutral and let the clutch out. 

The clutch is not designed to be employeeeed as a neutral gear.  When you seess the light turn yellow, then put your Spicer into 3rd gear.  Sometimes this is easier than first gear.  Then put it into first.

Finally, if that does not work either, try rolling to a stop with the tranny in neutral with the clutch out with the shifter just resting against first gear, just enough to "feel" the dog clutches engaging.

Then, after practice, you will be able to "time" the road speed and engagement feel to quickly put in the clutch and quickly "pop gently" your mighty Spicer 4-speed crash box into first without grinding.

Works for me.  This is a common truckers technique to drive a truck with either a very bad clutch or a very worn out tranny which would normally be very hard to place into starting gear standing still.

Finally, and this is a personal thing-you will get different opinions on this-I always use the clutch when up or down shifting, particularily with only a four speed.  Priceless equipment.  Good luck.
Title: Re: Engaging a Spicer
Post by: Len Silva on September 13, 2007, 02:09:53 PM
Check the oil, should be 30 or 40 wt motor oil, same as the engine.  Someone may have put gear lube in there.

Len
Title: Re: Engaging a Spicer
Post by: gus on September 13, 2007, 05:54:14 PM
Melbo,

Just like you I don't use my clutch after getting started either, doesn't seem to affect my shifting one way or the other.

I use the same system as HB for rolling to a stop except that I push the clutch in just before putting it into first because if you don't sometimes it will take a big jump forward when it goes into first.

My Spicer 4-sp uses 50w oil but don't know about your MCI, it may be different. Check your manual. One thing for sure it doesn't use 90w gear oil, those old Spicers have oil pumps and 90w is too heavy for the pump.
Title: Re: Engaging a Spicer
Post by: Melbo on September 16, 2007, 08:17:39 PM
Thanks for all the replys

I have been out of computer range for a couple of days.

I have checked the oil and it is low so I will top it  off with some 40 wt engine oil

It goes in for an alignment tomorrow morning

Thanks again for all the tips I will definitely use them

Melbo
Title: Re: Engaging a Spicer
Post by: Ncbob on September 17, 2007, 04:42:11 AM
Melbo, as I have mentioned numerous times here on this subject..the clutch adjustment is very important on these MCi's. It's a simple procedure and takes only a couple of minutes.

Secondly, I changed the oil in my Spicer from 40# to 50# Racing oil.  I feel I get better lubricity in addition it maintains its' viscosity better and helps slow the gears down for the shift period.  Sure made a better shifter out of me and certainly didn't hurt the Spicer.

NCbob
Title: Re: Engaging a Spicer
Post by: Dreamscape on September 17, 2007, 06:30:09 AM
NCbob,
How long have you been running that 50#? Any others doing that? Sound like a winner to me!

Paul