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Post by BruceH on May 4, 2005 19:29:44 GMT
__. A few weeks ago, I identified a "highway gear" gearset for my "P-reg" (1976) Daimler Fleetline bus. The overall gearing in the Fleetline can only be changed by swapping out the "spur gears" in the auto box. Within the box, there's basically an output shaft which drives a spur gear pair. This spur gear moves the drive to the rear of the gearbox and also passes the drive on to the bevel gear. This bevel gear turns the drive 90 degrees and turns the prop shaft to the rear axle. The bevel gear pair is in a separate housing which can be removed from the gearbox shell -- the spur gears (and thus the overall gearing) is within the transmission and can only be changed by a full rebuild of the auto box.
__. There was a tag on the transmission in my bus indicating that it was rebuilt about 10 years ago. I did a web search on the company but found that it had been wound up about 1999. Through Gardner engines and transmissions, I found that the old company had been purchased by some employees and their new companies was still rebuilding transmissions.
__. I found that they had a US-rep company in the US so I ordered a rebuilt transmission (they offer a "core" service -- my old transmission will be shipped back to them) with the highway gears.
__. The new transmission arrived in Charlotte NC a few weeks ago. It's in my bus now, awaiting a little other work so that road testing can be completed. On the drive to the transmission shop in Charlotte, the best "cruising" speed was about 46 MPH -- it would go faster but was obviously not "happy" doing it. It will be interesting to see what the new cruising speed will be -- the overgearing is changed by about 18%.
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Post by Jonathan Smith on May 4, 2005 20:37:51 GMT
Hi Bruce,
That sounds very interesting, UK double deckers are generally limited to around 50mph as that is the speed limit on single carriageway roads in the UK. The fleetlines were built almost exclusively for service work and would not be expected to go faster than 40mph.
I have heard of vehicles such as the Routemaster which had different differential ratios to suit the intended use. The red buses intended for use in the city had a diff ratio for a low maximum speed whilst the green buses intended for use out of town could go faster.
The leyland leopard also offered two diff ratios depending on speed required. I believe that my Seddon should be capable of 60mph with the present gear box and diff, she currently does about 55mph flat out on a level road.
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Post by BruceH on May 5, 2005 0:04:05 GMT
__. Yes, the Daimler company originally offered three different "spur gear" sets, allowing for a "city" gear, an intermediate gear, and a "highway" gear. I hope that my original was the lowest gear set -- that way the new gear will give the maximum advantage.
__. Although a few more MPH will be welcome, I'm more interested in reducing the RPM while crusiing (it's always immediately apparent when setting off from a stop that it was WAY overgeared with the original gearing -- not surprizing when you consider that it was made to carry 99 people). It will also be interesting to see if there's a difference in fuel consumption. I'm already getting 10-11 MP-US-Gallon -- that's about 12-13.3 MP-Imp-Gallon and that's very good so I'm not choked about it but improvement is always welcome.
__. BTW, the company that prepared my gearbox is "Queensbridge Transmissions" in Wakefield, Yorks. They worked with me through all the planning and completed the work and got the box shipped in a very short time. They seem thorough and competent.
Best wishes, Bruce Henderson, Wallace North Carolina, USA (1976 "P-Reg" Daimler Fleetling, double decker, 33 ft long)
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Post by Jonathan Smith on May 5, 2005 8:13:55 GMT
Do you have semi automatic gear change or is it fully auto? I used to drive fleetlines and they were all semi automatic.
Some of them have "crawler" gears, so you can pull away in 2nd or 3rd gear rather than 1st. I understand there is also a conversion to make the semi auto fully auto. You put the gear selector in top gear and it acts fully automatic.
If you have a fully automatic with kick down, the bus normally pulls away in second, but if you engage kick down from stopped it selects 1st gear. That used to drive me mad when I was driving Olympians in Edinburgh ;D You try to floor it pulling away and you end up in 1st gear crawling away.
Do you have any photos of your bus? Is it a DMS?
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Post by BruceH on May 5, 2005 14:07:39 GMT
__. My bus is fullyauto. The gearshift selector has only two positions "R" and "A" - both are at the bottom of an upside-down "U-shaped" selector gate. It's spring loaded to to go to the right side of the "U" which is the "A" side. Neutral is to the top of the "U" - there's a detent knob which must be moved to go to "R".
__. Vic Rabb, who owns US Bus in Charlotte (where the transmission is being replaced) has a Bristol VR double decker with a "multi-finger" semi-auto shift mechanism. My bus seems to pull away in first - the "throttle dip" which automatically blips the throttle as the box shifts seems to work very well.
__. My bus appears to be a DMS. It's 33 feet long with two doors. The placard next to the rear door reads:
Maximum Passengers
Seated - Upper Saloon - 44
Seated - Lower Saloon - 36
Standing (Lower Saloon) - 18
Thus, total load of persons (including driver) is 99 persons. The engine is a Leyland O-680. No photos now, but the bus goes to paint next and I'll get a snap of the bus when it comes out.
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Post by jimmy193 on May 5, 2005 17:02:20 GMT
Bruce,
Can't wait to see the pics.
Jim
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b
New Member
Posts: 1 
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Post by b on Jul 13, 2015 1:30:13 GMT
Hi,
I know this thread is really old but I found it searching on Google. Looking for help! I have a 1978 fleetline and have a problem with transmission. Wondering if anyone here can help me understand how I can determine if it's a transmission problem or something else. I'm not even sure who I can speak to in my area about it -- I'm located in upstate New York.
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