Bus Engine/Gear Problems

last SG · 2007-06-18T00:28:13+00:00

with regards to dave post the first paragraph i abuse-ly use the phrase "sticky gear". i once had SBS175 on s30 going first gear allthe way on the ECp.oooh...

201911 SG

Just took SBS 165 J on perm service 54. Engine sounds like stuck in first gear, eg when the bus accelerates, it's one continuous sound, unlike other buses, where you can hear the gears changing. Sorry for my poor explanation, but I don't really know how to put it. Let's just say that it sounds a bit like the Darts' Allison gearbox. What is it that causes the difference in the sound of the acceleration? Actually SBS 140 E also had the same sound when I took it last December, but it seems to have been fixed.

(Off topic: Despite the problem, the BC still chiong like nobody's business, and the engine was roaring loud Razz )

Scania N113CRB luver SG

Is what you said also known as gear slippage ?

Btw what you mentioned , i've noticed this in some other buses . Some SMRT buses are now getter more and more prone to it . TIB604R , TIB725A , TIB967T , TIB1011U are some of the buses that have slip gears .

As told by someone , Mercedes Benz and ZF gearboxes are prone to gear slippage.

stooper SG

Common Merc problem... Laughing

Bus jammed in first gear.

TWS4793 SG

Some Volvo buses do have this problem too. SBS 0866U kenna suffer from this problem.

The other day, the bus cameoing on Service 39 was almost reaching Tampines Interchange. It was about to move off when the bus got stuck, holding up a 65 DD, a unid SD and three other vehicles.

BluBlur SG

It has been a prob with SMRT Buses for a few years, but they are doing fine.

Many ZF Habits had this slippage, but are also rectified. There are some oddball cases, such as TIB 469P and 495M slipping 2nd time after a fix.

Currently, TIB 466Y, Habits 1023K (?), 1099S and 1139K Habit has slipping gears.

So many WLDEP buses have been fixed, like TIB 1000B, 1061A, 1063U, 1064S, 1066L, 1067J, 1070Z-1074M, 1077E, 1089X, 1091M, 1104K, 1105H, 1110S (the one burnt down), 1111P-1113J, 1130J, 1138M, 1141C, 1143Y, 1169Z (2nd batch), 1187X (Volgren). The situation is rather bad with older ZF Habits, oddly the box and Citaro lookalikes are ok.

Most ZF slippages start with tardiness during 1st to 2nd gear. Then occasional slipping, characterised with sudden jerks and gearbox "grinding". The full blown is when gears appear to change, but revs higher than usual plus the sound of engine in neutral when accelerator is released during motion.

Scania N113CRB luver SG

TIB1132D had also been fixed , after almost a year of gear slippage . Kudos for SMRT who rectified the problem ! Very Happy

Sudden jerks .... So far i haven't experience one yet . But the engine sounds like CVT-ed to me . Shocked And Volgren bendy having slip gears ? Wow ....Then the bus must have been damm noisy liao !

Oh i rmbr , maybe u refering the sudden jerks to VO3x ? Some VO3x 2nd batch i took have gear slippage too , and the sudden jerk rocks throughtout the entire bus .

Scania SG

It seems that Merc and ZF gearboxes tend to have these problems, only encountered one Voith with this problem.

BluBlur SG

Yup, 1132D had this problem for a looong time. I wonder 1131G has been fixed.

Jerks are seldom though. Gear crunching (abrupt transmission from 2nd to 3rd due to tardiness) and a audible knock when 2nd gear is engaged (when slipping signs occur) are more common. When slippage finally happens, there are surprisingly no jerks, the transmission appears to be even smoother!

When the Volgren 1187X had slippage, the entire Woodlands Int can hear the revving when it leaves a berth as though something is stuck. It was fixed in less than 2-3 months, probably due to the noise.

I have only seen a Voith breaking down, that is TIB 1193C. The same tardiness when switching to 2nd gear, and over 2 weeks of neglect the gearbox gave up completely. The last night before the bus went for repairs, it ran only at 1st gear for the full feeder journey.

I feel SBST fleet is better in this area, although i take them less frequently. Except for early Leyland buses that are starting to age.

^tamago^ SG

i think SMRT just overhauled all their ZF transmissions recently. Laughing

BluBlur SG

Appears to be an incomplete one.

What you do mean by overhaul?

off_service SG

With their recent tenders for ZF parts and stuffs Laughing

^tamago^ SG

Yeah. When I saw it last time, I knew the end of these problems is near. Twisted Evil

BluBlur SG

Some Voith gearboxes tend to jerk at the 2nd gear. It's like 1st gear for extended timeframe, then suddenly jerk to next gear.

I suspect it's due to poor gearbox maintenance and the way drivers handle the bus, such as gearbox revved up very frequently due to flooring of accelerator.

TIB 1246J (2nd last Habit produced) exhibits this symptom.

I feel the flooring of accelerator affects engine transmission... yet some drivers do it all the time, with the irritating clacking sound, plus abrupt jam brake-then-accelerate. SBST and SMRT should take them off normal revenue service, send them for corrective training.

BluBlur SG

http://web.smrtcorp.com/tenders/tenders_awarded.html

this?

Scania N113CRB luver SG

http://web.smrtcorp.com/tenders/tenders_awarded.html

Scania N113CRB luver SG

If only im at WRI when 1187X got slippage . I like the roar of the volgren artics .. Cool

Hope TIB725A and TIB967T will have their gear slippage solved . These buses have gear slippage for quite a long time already .

Scania SG

TIB725A was ok when I took it in Dec 2004 on 167. The even longer ones are TIB499C, since at least 2003, and TIB795Y. TIB543H had a period of time this year where it had slip gear, but fixed. TIB1066L also needs fixing, aircon hot, slip gear.

Scania N113CRB luver SG

TIB1066L ...no such problems leh when i took it last month . The bus has smooth gear shifting .

Tok abt TIB543H , it did have gear slippage when i took it last time . Tink it occurred when shifting from gear 3 to 4 . The gearbox kinda becomes "neutral" and the engine rev quite hard , then suddenly kicks into 4th gear .

SBS1991J have this problem . It jerks like hell . That time took it on 66 by chance , and it had similar problems that i had mentioned earlier for TIB543H . When the bus shifts from gear 3 to 4, the gearbox kinda become "neutral" then suddenly kicks into 4th gear , HARD . It sounds like "wahhhhh....PANG!" ...The whole bus jerks violently . I wonder if it has been fixed noe .

^tamago^ SG

yeah~

MyPillowTalks SG

some bus oso liddat