Hey folks,
Been loving this community. Excited to start showing off my rig. I've got an old 1970 GMC "Fishbowl" transit bus with big 'ole 6v71 Detroit Diesel engine. It was converted into an RV by Coachman in '71. This thing has been a lot of fun and I'm deep in the reno process now.
My question is, does anyone have any ideas of where to hunt down the old bus manual for this thing? Either the GMC or even the Coachman convert? The inside electrical works but it is an absolute mess with previous owners adding new wires and not eliminating the old stuff. I'm trying to map it all out and also need info on the engine for maintenance.
I've tried googling every way I know how but I'm curious if anyone else has had luck tracking down manuals for your vintage buses.
Thanks friends!
Mary
Before I saw this post I made a long reply to your other posting about the battery situation and lack of cranking. In there I suggest strongly that you locate the manuals for your bus. First thing is to locate the original vehicle GM ID plate as I mentioned in the other post. With the exact model information you can look around for vehicle manuals. It will most likely be an TDH, TDM, SMH, or SMD prefix to a 4 model number. So something like TDH5303 or something similar.
They were originally mounted inside near the stair well on the forward vertical dash panel. Usually just above the panel that opened for storage access to the space under the dash right behind the door. Most likely it's either been removed or covered up by the conversion process. That sucks for sure but if you can take pictures of the bus inside and out and include the engine bay details I can help and the PBM can most certainly help with identifying it.
There may also be another location where GMC stamped the model and serial number in the steel of the steering drive-shaft covering tunnel located directly under the drivers seat. The PD highway coaches had an enclosed compartment there right behind the left side bumperette, but I don't think that the transit buses enclosed that area so you may have to crawl under and look around for the stamping near the steering system drive shaft and toward the bus centerline. Should be fairly large and really stamped deeply into the structural member, could be on the rear bulkhead too, I don't know where they did it on the transits. Obvious once found. That will tell you what you need to know.
Then you should check around and get an engine manual for the 6V-71. These are not hard to find but may cost as much as $100 or more. I have good luck with the manuals on Ebay and have acquired what I need from the various sellers there. Specific GMC bus model manuals, especially for the transits and suburbans are not so easy to find there but it's worth checking often to see what comes up. One thing to be aware of is that the GM buses with the V-drive configuration, which was all of them really, except the Scenicruiser, all had engines that turned the opposite direction from the normal right hand rotation found in all other applications like trucks, generators, pumps, you name it. They are all left handed turning engines and require some care in getting parts for them. That will be covered in the engine manuals and explained in depth.
One other resource you can try is to sign up on busconversionmagazine.com as I mentioned as well. Ask if anyone there can point you to a source for manuals.
Another thing you can try is to contact directly the (PBM) Pacific Bus Museum in Fremont CA. They happen to be very transit bus oriented and maintain a very good library of all things related to that class of buses. I think they offer a way to purchase a service manual copy for many of the bus models going back many years. Once you know the underlying bus model before the conversion you can begin to get a handle on what's what and how to repair and find parts for the vehicle systems. Won't help at all with the add-on conversion stuff, but that's how they all are. You may be able to get by with a similar model fishbowl style manual if you can find something close to what you have. PBM can also help you with that. GM was pretty good about using common parts across many different, but similar, models.
