First post, so please be gentle if this has been asked already. I searched, I promise! I recently bought a 1985 Dolphin on a Chevy chassis. It is a 24' slice of heaven except that after I bought it, I realized that it seems like I might have the only Dolphin on a Chevy chassis. That being said, I can't find any information at all on the internet because it is a Chevy, not Toyota. My current issue is that the speedometer doesn't work. The faster I drive, the faster it spins. Everywhere I have called locally says they don't work on the mechanical side, only appliances and such. Can you take an RV to a regular mechanic for this type of issue?thank youJ

The Chevy part is a Chevy G-series van. Not many shops work on 30 year old trucks, but. you need to be. looking for a good independent mechanic. RV shops usually don't mess with chassis issues. You might see if there are classic restorers in your area who might provide some knowledge. Cevy van has a decent following in the antique and classic community.You do know, you've bought an antique, by the standards of car collector community and some states for licensing purposes? in some states, it has been an antique for ten years.

Isn't it supposed to spin faster as your drive faster? OK, silly me, I suppose you have a speedometer problem. Good thing is that it IS simply a Chevy Van. Are you able to tinker with it to any extent? I'm not a shop, but I'd wonder if the speedometer cable from the transmission to the instrument panel needs a cleaning and lubrication. It may connect to a cruse control with one cable then to the speedometer with a second one. What I want to warn about is this: We had an Olds Cutlass of that vintage. Somewhere in/near the speedometer was a little spinner-looking thing. Not the one that moves the speed needle, an additional one. Turned out it fed a sensor that went back into the engine control system. When I cleaned/lubed the speedometer cables, the needle stabilized but so did the engine. Got the little "lope" that it had around 45-mph to go away.Anyhow, being "Dolphin" doesn't matter co a Class C. Still Chevy, and that's a strong feature about Class C's. They don't have the cobbed-up chassis-dash wiring that plagues Class A's, particularly older ones. And Tom, whatcha doin' up in the middle of the night? You're as bad as I am...EDIT: The thing I called "spinner" looked like a little MIRROR. It was optical feed back to the engine control. GM systems like ignition were centrally developed. By that I mean the same concepts applied to most similar purposes. So if our Olds wit a 3.8 Buick V6 had that little mirror, there's a good chance if lots of Chevys with V8's did too. If you chose to drive it with the speedometer disconnected it might not run well at all...

Does the odometer work? If it does then the speedo head is bad. You maybe able to find a speedometer shop locally that can repair it or get a replacement.

Parts would be available for that Chassis , I would look /search under 1985 pick ups. I had a 1985 K series Blazer and anything and everything is available for restoration purposes. Sounds like the speedometer head has gone bad, easily replaceable. Go to an independent mechanic shop that has been around for awhile in your town and talk to them. Not a big deal to repair.

Call a wrecking yard and get a speedo out of any Chevy/GMC with a similar instrument panel. They are all the same. Don't know how to install it?? Get the coloring book (manual without outline pictures). Read the instructions and put in the new one and not the mileage. I have done this before and just did a 95 Honda. That took a day to get to it..... Matt

85 Chevy Dolphin | Good Sam Community

tatest
Explorer II
Mar 18, 2015
That's a common failure mode for magnetic speedometers that have the freedom to move all the way around the dial after the spring breaks. Most don't have the freedom, so they will just peg at the high end and stay there.

Speedometer shop, repair is quite likely, could be low cost. If there are any speedometer shops left. Kind of like looking for typewriter repair.
mahaney
Explorer
Mar 18, 2015
The speedometer just spins all the way around. The faster I drive, the faster the needle spins. The odometer is accurate based on the gps app for my phone. I am taking it to a local mechanic this week to have them go through and check everything out.

J
chinook440
Explorer
Mar 17, 2015
i thought he said it works but just spins to fast ? that,s what i based my reply on ... but the describtion is kinda unclear so ???
enblethen
Nomad
Mar 17, 2015
Doubt whether it is a gear problem. More likely to be a cable length issue.
I am thinking this way as the odometer works but speedo doesn't.
Is the odometer accurate?
chinook440
Explorer
Mar 17, 2015
Sounds like someone probably swapped / changed your transmission before for a rebuilt etc. and did not reinstall the correct speedometer gears in the trans. to match your gear ratio and tire size.
mahaney
Explorer
Mar 16, 2015
Thank you all for the replies. I'm leaning more towards the actual speedometer being bad vs. the cable since the odometer works. I took the panel apart yesterday just to try and see if it is the cable or not, it looked good.

J
Matt_Colie
Explorer II
Mar 16, 2015
Call a wrecking yard and get a speedo out of any Chevy/GMC with a similar instrument panel. They are all the same.
Don't know how to install it??
Get the coloring book (manual without outline pictures). Read the instructions and put in the new one and not the mileage.
I have done this before and just did a 95 Honda. That took a day to get to it.....

Matt
klutchdust
Explorer II
Mar 16, 2015
Parts would be available for that Chassis , I would look /search under 1985 pick ups. I had a 1985 K series Blazer and anything and everything is available for restoration purposes. Sounds like the speedometer head has

gone bad, easily replaceable. Go to an independent mechanic shop that has been around for awhile in your town and talk to them. Not a big deal to repair.
enblethen
Nomad
Mar 16, 2015
Does the odometer work? If it does then the speedo head is bad. You maybe able to find a speedometer shop locally that can repair it or get a replacement.
j-d
Explorer II
Mar 16, 2015
Isn't it supposed to spin faster as your drive faster? OK, silly me, I suppose you have a speedometer problem. Good thing is that it IS simply a Chevy Van. Are you able to tinker with it to any extent? I'm not a shop, but I'd wonder if the speedometer cable from the transmission to the instrument panel needs a cleaning and lubrication. It may connect to a cruse control with one cable then to the speedometer with a second one.
What I want to warn about is this: We had an Olds Cutlass of that vintage. Somewhere in/near the speedometer was a little spinner-looking thing. Not the one that moves the speed needle, an additional one. Turned out it fed a sensor that went back into the engine control system. When I cleaned/lubed the speedometer cables, the needle stabilized but so did the engine. Got the little "lope" that it had around 45-mph to go away.
Anyhow, being "Dolphin" doesn't matter co a Class C. Still Chevy, and that's a strong feature about Class C's. They don't have the cobbed-up chassis-dash wiring that plagues Class A's, particularly older ones.
And Tom, whatcha doin' up in the middle of the night? You're as bad as I am...
EDIT: The thing I called "spinner" looked like a little MIRROR. It was optical feed back to the engine control.
GM systems like ignition were centrally developed. By that I mean the same concepts applied to most similar purposes. So if our Olds wit a 3.8 Buick V6 had that little mirror, there's a good chance if lots of Chevys with V8's did too. If you chose to drive it with the speedometer disconnected it might not run well at all...