CROWN Batteries?

[Sharkbonz]

Hello all!
New to the forum and Crowns!
Recently aquire a 1971 Crown, very clean and dry. Unfortunately it has no batteries and I cannot seem to find to information on 12v or 24v batteries. Actually hard to find any information at all. I know it's the Cummins 220 engine and a Fuller 10 spd. I have drive otr for around 25 yrs. So I'm not new to trucks. Any help, pdfs or hard copies for sale or share?

 

[flattracker]

Your Crown should take two 8D batteries. To my knowledge should run on 12 volts. Years ago I parted out a 1973 Crown and that is what it had. It also had a Cummins 220.

 

[Sharkbonz]

Your Crown should take two 8D batteries. To my knowledge should run on 12 volts. Years ago I parted out a 1973 Crown and that is what it had. It also had a Cummins 220.

That's definitely helpful, I measured the tray and it was 7"×20ish for two batteries. Thx again.

 

[Tejon7]

Hi neighbor! Nice to see another MT Crown.

Get on the Crown Coach Enthusiasts group on Facebook. There's a "files" tab in that group where you can download electrical schematics, driver's handbooks, and other goodies.

 

[flattracker]

Here is a picture of the batteries in the "new" crown. The "old" Crown has the same setup.

 

[Crown_Guy]

What they both said. Two 8D 12v batteries wired in Parallel so you get twice the current surge at start up. Look for the highest Cold Cranking Amps rating on the batteries. Commonly 1150 CCA but with some looking around you can find 1300 CCA too. Any decent battery place that sells heavy duty truck and bus batteries should easily be able to get you what you need. Don't be afraid to get a properly rebuilt battery either. If done correctly they can be as good as brand new as long as they change the plates and posts etc and make sure the case isn't cracked etc. I always seek out rebuilt batteries and they are usually only about $100 or so each.

8D's need not be hard or expensive to find but do some research and make sure you don't get taken for a ride by retailers trying for the $300+ price range. Find a good battery place that offers re-manufactured batteries, and make friends, you're going to need him as time goes on.

If you don't drive your Crown at least monthly the batteries will die in about 3 months of sitting idle. Just a fact of life we all have to deal with. I make sure to drive mine at least 30 miles every month to get the engine up to temperature and keep a healthy charge on the batteries. Starting it without driving it 30 miles actually defeats the purpose and causes other problems. Remember that they need to be driven as much as you can afford to and the more you drive it the better it likes it and runs better and you end up with fewer trouble all the way around.

Congratulations on getting a right proper bus. Don't worry too much about what you don't know yet. You can always reach out to me or other Crown owners for help and once you get familiar with it and how it's over engineered and built you'll grow to love the simplicity and ease of maintaining it. Parts for the running gear are still readily available since Crown used off the shelf heavy duty truck parts that are still in use today. Very little proprietary parts other than the body panels and such which are unique to Crowns.

You didn't say whether the transmission is an overdrive or not. If it's not an OD I'm guessing the top road speed will be around 63mph at 2150 rpms as that was the standard for Crowns built for school districts. The Cummins will turn faster than 2200 since the engine and governor are completely different than the Detroit's which shut down hard at the governed speed setting. Cummins don't work the same at all. This means you can probably get around 65 or more but you'll still be turning the engine at 2300+ to get the road speed.

The Fuller Roadranger is available in a direct drive in tenth or .87 overdrive in tenth. The way to tell is in what position 5th and 10th gear are located. If they are both to the right and Down then it's a Direct 1:1 tenth gear setup. An Overdrive will have 5th and 10th to the right and UP.

If you really want to take advantage of the Crown on those wonderful wide open highways you should consider a rear-end ratio change from the common 4:11 in most Crowns to something along the lines of a 3.90 which will give an instant 12 mph increase in top speed. Believe me cruising along at 75mph in a Crown is a religious experience. Rear-end ratio bump and even changing the 10spd into an OD will make your Crown into a real King of the Road.

Keep in touch and contact me directly if you want to. You've also got some very good company up there in MT with another Crown owner, Tejon7, who can help you out and if close enough you two can get together and he can show you stuff in person. Welcome to the Crown Owners Club. You've taken your first steps into a larger Universe of coolness.

 

[Sharkbonz]

Outstanding!

 

[Sharkbonz]

So it is an overdrive! Sweet, thanks again as a wealth of knowledge is always appreciated! Hope to get it rolling down the highway soon. I will be back for more answers soon I'm sure. Thank you everyone again.

 

[Crown_Guy]

If the Fuller shift pattern plate is still there you will see it clearly shown. It will also show the transmission model number. By the way you can get new ones from Eaton still today if you want a pattern plate. RTO-910 means: Roadranger Transmission Overdrive- 900 ft/lbs max torque, 10 speeds. (910). If it's an RT that means Roadranger Transmission..no-overdrive.... - 910 .

For all those out there wondering. It's also most likely that the 10 speed was installed after the bus was made and the Fuller ID plate not added by whoever did the swap. It probably was originally a 5-spd from Crown. They could have easily put in the 10spd when built but it would have been an extra cost option that not everyone wanted to pay for, unless it was a mountain school district or Charter Company looking for the best performance.

At least you now know an important feature of your Crown and can drive it properly and shift it into the correct gears as you up-shift. It makes a big difference to do it wrong and go from 3rd/8th to 5th/10th skipping 4th/9th and wondering what the heck is going on. Knowledge is power.

 

[nikitis]

I thought crowns come with battery disconnects because it's known they like to put them on the positive side which is wonky to me.

 

[Crown_Guy]

I thought crowns come with battery disconnects because it's known they like to put them on the positive side which is wonky to me.

Nope. MOST Crown don't have any battery disconnects. The vast majority of the Crowns I've seen have no battery disconnects at all. It's an extra cost option to have one installed when new and most never bothered with them. It's assumed they are running every day in service and the batteries will stay up. Crowns have an extremely simple and low drain electrical system to begin with. They MIGHT even have a radio (AM) as an option but not usually.

When the Crown is turned off and the ignition keys are taken out there really isn't any parasitic loads to drain the batteries like we have today with all the computers that never really are completely powered down. When the Crown ignition is off, and all the lights are off, the bus is dead as a door nail. The long term drain is from internal battery self discharge which is a known phenomenon and why I advocate driving every month or so at least 30 miles to keep the batteries up. You can always lift the battery cables which are easy to reach or install a proper shutoff switch which there are several designs to pick from.

My tandem was ordered by a school district with a ton of extra cost options including full factory air conditioning and many other items including the battery shutoff switch. But it's definitely the rarest of examples when compared to your average Crown.

Remember that Crown was a Coach and Body company and they built whatever the customer wanted and paid for. There was indeed a baseline school bus low-end equipment set mostly dictated by laws and common customer requests, but above that baseline the sky was the limit and anything was possible. This is why there really isn't any such thing as a "Model Year" difference in any Crown, merely the year of manufacture.

All Crowns are really unique in their own way since they were literally built by hand and assembled by craftsmen. As a Crown owner feel free to adapt and update anything you want to improve or change since that's what Crown would have done if the customer wanted it. My only caution is to not mess around with the underlying strength and engineering of the vehicular components or structure since that could cause driveability or safety and handling issues.

 

[nikitis]

Oh ok, so it's not as common as I thought then.

If it has an ECM there is parasitic drain in any case. If it's all Mechanical then no.

Batteries can last 2-3 years without a charge if completely unplugged.

My 1995 ECM drains enough that if I don't drive it within 2 weeks the brand new battery will be dead, but I retrofitted it with a battery disconnect on the negative side of the battery cutting off all grounds, and now it's dead as a door nail and always ready to crank even if left for 4 months.

 

[cadillackid]

my mechanical DEV bus has a battery disconnect switch but i really dont need it... beiung all mechanical, it sat for a year while I was doing the driver area rebuild and MT643 swap... it still had LOTS of battery when it came to start it.. I had to disconnect a fuel line at one point and so it was a good bit of cranking and hand priming to get the fuel system going again and battery never even seemed low... I had forgotten to use the disconnect.. my red bus will have low enough batteries if it sits for 2 months to strain a bit when starting.. pop off about when you think it wont kind of thing... then the ammeter runs pegged out for awhile... so that one I try to keep my victron smart charger on it when i dont plan to use it.. the charger has ther ability to set the type of batteries you are charging and then will run in a maintenance mode to keep them up without actively charging them.. its an 'IP21' charger 30 amp. ive got AGM batteries and never have an issue..



I permanently installed one in the DEV so I can keep the batteries all topped off after ive used it as a mobile office all day..

 

[Iceni John]

My Crown, albeit a later-year rear-engine bus, has its original Cole-Hersee M-705 battery disconnect switch that completely cuts all loads from the start batteries (except the 8mA draw for my engine's ECM). C-H has superceded it with the M-750 switch, but they're essentially the same. Don't use a battery switch that can't handle the starter motor's current: my Delco-Remy 42MT starter motor is rated at up to 10.5 horsepower, which at a nominal 12VDC is about 650 amps (it takes a lot of current to turn a big engine, especially if the oil is cold).

My bus originally had two 8D start batteries, but I've replaced them with Group 31s. I just recently bought another pair of 31s after nine years of excellent service from the old ones: they still had good life in them and would spin the engine easily, but who knows when a plate could break or short out, so I replaced them before they could strand me somewhere. The 31s are 1000CCA each, not much less than the old 8Ds, but they obviously have a lower Reserve Capacity than 8Ds. For me that doesn't matter because I have 840Ah of house batteries that I can connect to the starter if the 31s can't start the engine. I also like not having to carry 135lb batteries! As Mike says, it's prudent to drive (not merely start) the bus every month to keep the batteries charged and to prevent problems caused by long-term lack of use; I use two 12V-12V battery maintainers to keep my start batteries happy, powered from the house batteries that are constantly charged from the sun.

As you may have already gathered, Crown buses (like the folk who own them...) are not usual or standard or normal. They deserve a different standard of care and attention, but they can last essentially indefinitely if treated right. The Crown Coach Junkies group has several members with 1950s Crowns that are still as reliable and practical now as any newer buses: the biggest difference is that they're just more fun than almost anything else on wheels!

John

 

[Crown_Guy]

I think a slight clarification might be in order to dispel any confusion regarding the Electronic (DDEC ECM etc.) vs a purely mechanical engine installation. Crowns historically were of the underfloor pancake mid-mount configuration. The exceptions would have been for any custom Highway Coaches with rear engines like the normal Greyhound types we are familiar with. Crown built a really nice Highway Coach and they are also still around but in much smaller numbers since they just didn't make that many.

Of course they made the Crown II's toward the end of the company's life that were rear, (I know about the handful exceptions John), engines with 3 engine options, Detroit Diesel 6-92, Cummins 8.3, Cat 3208. They may or may not have had electronic controls. Some of the 6-92's were all mechanical while most of them later on had DDEC's. John has a Crown II with the exact same drive line and HT740 transmission setup that was the standard for nearly every highway coach made by everybody at the time. So he has a Greyhound with a school bus body...

My point here is simply that the normal mid-engine, mostly school bus used, Crowns were all either a Cummins, or later on, a Detroit Diesel in-line 6 cylinder engine (to lay flat sideways under the floor). In every case these were only purely mechanical engines with no electronics of any kind to control them. The only electrical components involved in the engine operation was a shutoff Skinner air valve that operates the governor shut down lever(Detroit), and a run solenoid built into the fuel pump internal fuel line on the Cummins. In both cases it's possible to manually override them in case of an electrical fault. And they are only active when the bus ignition is on and the engine is running. These in-line 6 cylinder engines never had any electronic injectors or DDEC (Detroit) controls at all, same for the Cummins. These can be driven without any batteries on board, once they get started of course, (I've done it), but they aren't hard to bump start if you have air to release the parking brakes..... I've done this too on occasion with only 4 guys pushing the bus, Coaches and Crowns.

Extremely simple and easy to understand and repair and keep on the road is the nature of Crowns and why we all covet them so much. They are unique.

 

[Sharkbonz]

Yes the plate is there, and it really moves down the road in 10th! We appreciate the help and knowledge. Got it home and just posted. Was a sweet ride on the air ride for sure!

 

[Crown_Guy]

I just realized I replied to another of your threads on this Crown. So you got the transmission OD stuff under control and have experienced the full awesomeness of the air-ride, which I'm jealous of, of course.

I'm hoping some day to find one for myself to enjoy again. They are very rare to find. When I worked at Embree Buses in Pasadena we had three of them with air-ride, standard mid-engine Crowns, and loaded with TONS of extra options typical of the Embree fleet, way too numerous to list. But that was Embree and how I learned the business. Learned from the very best. I still miss those air-ride Crowns. I drove them for years.

Like I said in your other thread nothing like them, and I still drive coaches today professionally and I think Crowns are better in many ways. For a private individual with a typical family budget only a Crown or some other good school bus is feasible. Any brand of highway coach is a whole different level of expense and painful overhead $$$ requiring a very large and never ending bank account.