Spicer shift into first at stop light
 

Spicer shift into first at stop light

Started by bevans6, July 31, 2009, 06:16:40 AM

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bevans6

What are the best strategies for shifting into first after waiting at a stop light? 

Brian
1980 MCI MC-5C, 8V-71T from a M-110 self propelled howitzer
Allison MT-647
Tatamagouche, Nova Scotia

TomC

I know at least with big rig trucks, the clutches have a brake in them to stop the transmission from spinning to be able to engage the gear without crunching.  It worked by pushing the clutch pedal all the way to the floor and then pushing on it some more for about a second or two, and then the gear shift would just slide in without crunching.  I would think that the clutches on buses would also have a clutch brake since most of the equipment on buses are shared by trucks also.  If the clutch has a brake, it just needs to be adjusted (at the clutch, not with the linkage) to operate properly.  Good Luck, TomC
Tom & Donna Christman. 1985 Kenworth 40ft Super C with garage. '77 AMGeneral 10240B; 8V-71TATAIC V730.

WEC4104

I'll assume that the question deals with how to minimize the grind that would take place if you quickly jam it into first after the trans has been sitting in neutral with the clutch pedal out.

Of course the easy (but not helpful) answer is to keep the clutch pedal depressed.  It also has the side benefit that you can skip one of the workout stations at the gym the next morning.

Somewhere I recall somebody posting that the only way they could get into first without grinding was to shut the engine down and restart in first.  ::)   I guess that could be done, and you could tell everyone that you have one of those new fuel efficient hybrid that shuts the engine off at lights.

But seriously, the best advice I can offer is two-fold.  First, anticipate when the light will be changing byu watching the crossing traffic's yellow light.  If I hold my clutch in and wait for 10 seconds, I get virtually no grind.   Secondly, would be to switch the oil in the Spicer.  If the seals are in good shape, a fully synthetic might help.  

If you're going to be dumb, you gotta be tough.

Len Silva

You most likely do not have a clutch brake.  There are a couple of ways to get it into gear.  

The easiest (for me) is to downshift into first before coming to a stop.

The second is the put the transmission into third gear to stop the rotation, then into first.  It will still grind a bit but not as noticeable.

Patience.  Hold the clutch down for thirty seconds or so to give the gears time to slow down.

If you have an easy starting engine, just turn it off and restart in gear.

Hand Made Gifts

Ignorance is only bliss to the ignorant.

gumpy

What Len said... start by putting it into 4th, and bring it down; 3rd, 2nd, 1st. Usually, this will bring it right in with little or no grinding.


Craig Shepard
Located in Minnesquito

http://bus.gumpydog.com - "Some Assembly Required"

Runcutter

Brian, as a former driver and instructor on 4905's (among others), we always slid the transmission into first when coming to a stop - either for a light or for brief passenger loading/discharge.   

As the coach is almost stopped, slight forward pressure will drop it into first with no audible grinding.  You'll feel the gear teeth, but not hear them.  Yes, you'll have your foot on the clutch for the duration.  I'd submit that, if this is a problem, your clutch return pressure should be adjusted.  By the way, that's what I still do now with our 4107. 

I do remember one stick shift city transit we had that did have a TMSB clutch (two men and a small boy) - and that was indeed a workout after 10 hours.  Still more fun than an automatic.

Arthur
Arthur Gaudet    Carrollton (Dallas area) Texas 
Former owner of a 1968 PD-4107

Working in the bus industry provides us a great opportunity - to be of service to others

zimtok

With my 4104 I usually slip it into 1st gear as I'm comming to a stop as Arthur has explained. I have an air assist clutch which makes it even easier to hold the clutch in.

If I don't have it in 1st when I'm at a standstill I push in the clutch wait a second then ease it into 1st gear. It sometimes helps to pull it into second then straight up to first.




.
1960 PD4104-4971 - Memphis TN

Buy the new Eddie L Smith CD "STAYIN LONG" at:
http://www.eddielsmith.com
Everyone is welcome to any of our gigs listed on the website.


buswarrior

Get your clutch lightened up, if you can't hold it in for the duration of a red light.

As noted, I'll add a few more descriptive words. As the coach rolls to a stop, often in 3rd or 2nd, leave it in that gear until the revs reach idel speed, then push in the clutch as it bogs. The coach stops, and the shifter will slide ever so nicely from that gear into first without a problem. Wait for the light to change and dead throttle it off the line.

You have read RJ's shifting article over at BNO? 
http://www.busnut.com/bbs/messages/12262/16204.html?1167073154

Every grind in that old box is one less grind left, and you can be sure that the paid help that abused the crap out of it in it's former lives took out a lot of grind!

happy coaching!
buswarrior

Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

bevans6

So everyone is doing what I was already doing.  Oh well, thought I'd ask anyway!  i've done a lot of work on the clutch, maybe it will improve things.  Haven't driven the coach since I did that. 

thanks, Brian
1980 MCI MC-5C, 8V-71T from a M-110 self propelled howitzer
Allison MT-647
Tatamagouche, Nova Scotia

viento1

I miss the spicer, Auto trannies... booooooorrrrring

I agree with bus warrior - I felt guilty and when someone else was driving while I was sleeping - it was worse than rumble strips. Anyway, to appease my conscience I always used reverse to slow down the tranny.
Ok, it's time to go on another road trip.
www.randalclark.com
MC5

WEC4104

Quote from: buswarrior on July 31, 2009, 08:06:28 AM
As the coach rolls to a stop, often in 3rd or 2nd, leave it in that gear until the revs reach idel speed, then push in the clutch as it bogs.

Actually, that's a separate topic I've occasionally wondered about myself....  Let's say I am approaching a stop sign or traffic light and know I have a stopping point some distance ahead.  If I'm in second or third, I rarely stir through all the downshifting, and simply lift up on the throttle and begin my braking.  What I have pondered is the point to dump the clutch pedal as I continue braking.  1200 rpm?   900 rpm?  750?   idle?  I think I tend to error toward the high side (1000-1100) figuring I don't want the brakes to be waging war against the governour.

Opinions?
If you're going to be dumb, you gotta be tough.

gus

I do what Arthur says in his second paragraph and it works great.

Trying to shift into another gear just results in the same grinding as trying to get into first.

Once my trans warms up there is no way I can shift from neutral without shutting down the engine, so that's what I do!!

I've spent hours adjusting my clutch and replaced all the linkage ends and pins both for the clutch and the trans.
PD4107-152
PD4104-1274
Ash Flat, AR

Dreamscape

When I'm approaching a stop I leave it in gear to just before it coasts to a stop, then run through the gears as others have explained and it slides right in, or rumbles, most of the time! Now downshifting for me is a different story, Yuk!

I just need more practice! ;D

Paul
______________________________________________________

Our coach was originally owned by the Dixie Echoes.

Dallas

If you'll simply take the top cover off of your transmission and using an angle grinder, cut all the teeth that you can reach down about 3/8" while turning the gear pack over, you won't have any more grinding problems.

JohnEd

I was told that the "wet" clutch could "not" be put in gear after stopping without shutting down the engine.  Seemed that there was just too much fluid coupling to overcome.

Can those little clutch pads that brake the output side of the clutch to a stop be replaced?  I remember that someone said that they were rarely serviceable for very long after a clutch replacement.  True?

I watched Tom(PVC...) drive thru city streets without even the slightest hint of a problem or balk and he was driving his 06 like it was a Lotus.  Just so you know that "it can be done".  The 06 lives up to its rep as the "Sports Car" of buses.

John
"An uneducated vote is a treasonous act more damaging than any treachery of the battlefield.
The price of apathy towards public affairs is to be ruled by evil men." Plato
"We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light."
—Pla