GP 30 Spectrum

[McCullough]

I have an older GP30 that has been converted to DCC. Unfortunatly it runs like a tank, groaning and grinding it's way along. I think the problem could be in the trucks and the iner mechanism. Is there anyway I can fix this problem? How do I tear the trucks apart? Would love to have a smooth running machine! Thanks HJM

[richg]

How old?
Like the one below?

http://www.hoseeker.net/assemblyexplosionbachmann/bachmannemdgp30diagram1990.jpg

Or is it like the below?

http://www.bachmanntrains.com/home-usa/dwg/dwgs/60801.pdf

Rich

[McCullough]

Hi Rich, I think I bought it around 1990, it has very limited running time. The motor seems OK but the grinding cause a higher power drain from the way it runs. Just want to know if I can get into the gearing of the trucks. from your recommended web site s it is hard to know which one it is as they both look the same to me. Any help would be much appreciated. H

[sd24b]

I have an older GP30 that has been converted to DCC. Unfortunatly it runs like a tank, groaning and grinding it's way along. I think the problem could be in the trucks and the iner mechanism. Is there anyway I can fix this problem? How do I tear the trucks apart? Would love to have a smooth running machine! Thanks HJM

my older gp3o's trucks were attached to the frame by a small screw.  There is also a clip on the bottom of the truck which must be removed to obtain access to the gears. Check your flywheels and a drop of oil to your motor bearings may help also.

[richg]

The HO Seeker link indicates that this is a 1990 loco with a pancake motor on one end. The other truck is underpowered if that is any help. This assumes the link I showed is accurate.
Have you removed the shell and taken a look at what you actually have?

Below is a link to the Bachmann diagrams that HO Seeker has.

http://www.hoseeker.net/bachmann.html

Rich

[jward]

the op has listed this as a spectrum. as such it would not have a pancake motor. spectrum was bachmann's effort to gain credibility with us serious modellers. the gp30 was one of the first spectrum models, along with the 44 tonner.

as a spectrum, this locomotive would have the split frame drive of the second part sheet. taking the locomotive apart is relatively straight forward. remove the body, the frame halves are held together by insulated screws, remove them, lift the one half of the frame off, and the trucks lift right out. the sideframeand gearbox covers can be removed by prying with a screwdriver. once you get inside the locomotive, disassembly should be intuitive.

[bapguy]

I have a GP30 that is DCC on board. I'm planning on installing sound in mine as well. Here's what I found out: my unit is the split frame type, the motor is held in place by the frame. i believe the sound is from the motor vibration being transfered to the frame. On mine, I tok the frame apart ond ground down the frame where it holds the bottom of the motor. I took some caulking and put some on the frame. I put the motor back in the frame and made sure it was straight. I then put a bead of caulk on the other frame half and put the frame together making sure the motor was straight. I put the screws back in the frame . I took apatr the trucks, cleaned up the grease in them and lubricated them with oil. Reassembled the loco and ran it. It's still a little noisey but this made a big improvement in the growling noise. I noticed the motor still touches the frame on the ends. This is whrer the remaining vibration is coming from.  Joe

[richg]

Bath caulk works quite well for cutting down on sound from the shell and motor. A thin film between the shell and frame can help but this requires careful experimenting.
Much easier to use than Silicone and no Acetic acid either.

Rich

[bobwrgt]

I found alot of the noise in Bachmann diesels is from the drive shaft they use. Some are bent and  not straight. Watch them turn and see if they wobble. Also i have eliminated some noise by removing some of the slop movement front and back. Slide the coupling on the worm shaft closer to the motor.

Bob

[richg]

I found a lot of the noise in Bachmann diesels is from the drive shaft they use. Some are bent and  not straight. Watch them turn and see if they wobble. Also i have eliminated some noise by removing some of the slop movement front and back. Slide the coupling on the worm shaft closer to the motor.

Bob

Some loco motors can have quite a lot of end play and oscillate in both directions. A solution I found some years ago is to use a very thin washer the size of the motor shaft. NWSL sells them. About the thickness of paper. Slit one side and carefully insert the washer over the motor shaft with a pair of tweezers. Little tricky but it has helped some reduce motor end play issues. Sometimes you just have to go with what works.

Rich

[Doneldon]

Joe-

Plastic shells can resonate to normal vibration and amplify it, even if you've
cushioned their contact points. A little smear of something gunky, like caulk
(plastic safe, of course) can damp these resonations and harmonics quite a
bit. Just make sure that you don't have any clearance problems between the
goop and moving parts.

                                          -- D

[McCullough]

Thanks everyone for your responses, I think I have discovered that the drive gears are out of round. Although 20 years in the box it has only run about 20 minutes. As Bachmann advertise lifetime guarantee I think I should return it to Bachmann and see what comes from it. I believe you mail it back with $10.00 enclosed. Can Bach-Man advise me on this? H.

[Doneldon]

HJM-

I think it's $25 now, but it should still be $10 for you if you have the certificate.

                                                                                                            -- D

[jbrock27]

To return your loco ( tender) in for repair send to Bachmann Inds. 1400 E. Erie Ave.
Philadelphia, PA 19124. If your loco is under 1yr. please send a copy of your receipt. if
you do not have your receipt, if it is older than a year, or misused or abused, please
send the following service fee:
$15.00 all standard non DCC locos with the exception of large scale
$25.00 standard DCC and Spectrum N and HO
$30.00 Williams, ON30 and Standard Large Scale
$50.00 Spectrum Large Scale
Please include complete address and phone number. Parts and accessories are only covered
for 90 days. Additional cost may apply.
PRICES ARE SUBJECT TO CHANGE.

Mac,

I have had the same issue with a Plus GP35 that I have that I posted here for help with.  Except for the details on the shells, they are pretty much twins, using the same components.  The above is what I received from Bachmann when I inquired about sending it back.  I have not done that but I have tried some of the things suggested here like trying to cushion the motor in the space where it sits in the frame.  It helped some, but still makes annoying vibration sounds.  I liked Ds and Richg's suggestion to try either a bath caulk or some other plastic safe caulk, but have not tried this yet either.  I have to figure out how I will get the caulk down even enough so that when it cures, I don't have a problem getting the shell to screw down to the chassis.  Good luck solving it; I can tell you the noise has driven me batty.