| Author | Message | ||
| Smitty (205.188.116.135) Rating: N/A |
I am interested in buying a 1970 Crown Coach conversion. Before I go to look at it and then have it checked out I would like to find some info about it. Can anyone tell me anything about a 671 pancake Detroit Diesel. Are parts easy to get, how much to rebuild/replace, any quirks. Any advice, links or recommended literature would be appreciated. Everything about the bus sounds good except the mechanics, it has over 300,000 miles, but the price is right and if not to much trouble to bring it up to snuff might be worth the price. | ||
| Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A |
The Pancake 671 Detroit is about the same as a regular Detroit, only it is laid on its left side at about a 80 degree angle and is as flat as a pancake--thus its name. Crown used "N" Detroits as well as various rated turbo models. Ratings varied from 210-218 HP all the way up 278 HP. Turboed Detroits are more desirable. A Jake Brake would also be super cool. Other than some modifications to the oiling, cooling and exhaust systems, every part will fit, along with filtures and stuff. The mill is in the middle of the coach under the floor. My '74 Crown 3-axle coach has 378,000 miles, but is in absolutely mint condition. Seems just about everything was overhauled not soossss long ago by the last school district to lease/own her. Your Crown may be in the same situation. Since the entire coach is designed to be pretty much infinitely rebuildable using standard Class 8 heavy duty truck components, the total road... ...mileage usually is NOT a good indicator of the overall condition of the bus. I would recommend that you spend a couple of hundred bucks and a couple days of your time and have the bus... ...inspected from bumper to bumper at a regular heavy duty truck or coach repair shop. They can certainly tell what kind of condition the old girl is in. It will be $$$ well spent. There are a couple of specific things dealing with Crowns that one should know. Crown had two (2) types of windshields...flat and curved. The flat glass is more desirable as it is cheap... ...to replace compared to the curved glass which is now about $500 bucks per side out here on the West coast. Back East...who knows? My Crown has the curved glass and I wish it did not. Another thing about Crowns is that quite a few have the great famous (or infamous?) RTO 910 or RTX 1150 10-speed Roadranger tranny. My Crown has the RTO-910 and it is sooosss max cool. The other manual tranny Crown used in 1970 was the RT-905 and later the RT-1105 5 speed Fuller. This is a super good box, but not as fun or efficient as a 10-speed. And...of course by 1970 Crown used the MT-640 type Allision a lot of times with the Detroit. This Allision is a 4 speed unit and works very well in a coach application. Your power steering could be either an air assist unit or a hydralic assist type with the Ross steering gear. Either type will work well. The bus can be safely operated with either type properly disconnected. Tires and wheels are the last thing. Check to seess if you have 22.5 radial tires with tubeless Budd type steel disk wheels. Older split rims with tube type 20 inch wheels are OK, but most... ...of us change them out to the newer type. Any good heavy duty truck shop can work on your Crown. They were designed and built so. They handle like a sports car... ...stop on a dime and give you change, and the Detroit will usually deliver over 10 mpg--maybe more. I say have it inspected then make your decision Try www.crownbus.com for more info. CROWNS FOREVER! | ||
| Smitty (64.12.116.135) Rating: N/A |
Thanks for all the great info Henry. It has the 5 speed fuller. Another question, can they tow a 3,000 lb load behind it? I am going to look at it this weekend and if everything looks good to me then I will have it inspected by an mechanic. I just want to find out as much info as possable. | ||
| Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A |
Check to seees if your Crown has a rear trunk. If it does, it means that the main frame will probably (not always) stop just behind the rear axle(s). If it does NOT have a rear trunk, then you may be in luck. A heavy duty trailer hitch is easily tied into with the rear bumper which is connected directly to the frame. If your frame does not extend to the rear bumper, then you will have to do what I plan on doing and extending the frame down and through the trunk to the rear bumper. Then you mount whatever type of hitch or pintal assembly you may need. Either type of Crown can be modified to have a hitch capable of towing 3000 pounds. The Coach can handle the extra weight. One may have to take some care with the cooling system, but this I am told is no big deal. CROWNS FOREVER! | ||
| RC Bishop (128.123.221.206)
Rating: N/A |
Good post Henry.....I've been waiting for you to respond. Very comprehensive and helpful, I am sure. As you know, my Crown is a '64 Supercoach, Cummins 225 Turbo, RTO Fuller 10spd with Jake....and a Supersized trunk...  I know absolutely nothing about DD..... RCB | ||
| Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A |
I bo boed about the Fuller 5-speeds. The correct name is a T-905 or a T-1105. The letter "R" refers to a Roadranger multi-speed tranny which the 5 speeds are not. You may have the T-905M model gear sets in your 5-speed. These are around 5.47 to 1.00 first, a 3.25 or sooss 2nd, a 2.04 or abouts third, a 1.32 forth, and a direct fifth. Crown geared the rear ends to the needs of the buyers. Could be anywhere from a 5.13 to one (yeck!--very slow!) to about a 3.7 to one, which would... ....give you about 66 mph at 2100 with 12R X 22.5 radial tires. My Crown has 4.10's and along with the 22% overdrive 10th gear, will go right at 80 mph. CROWNS FOREVER!! | ||
| Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A |
Oh, man, I goofed again. I hate getting middle aged. I meant to says 72 mph at 2100 with 3.7 gears...NOT 66 mph. Sorry. CROWNS FOREVER!! | ||
| Gary Stadler (Boogiethecat) (68.7.217.217)
Rating: N/A |
Yakkkkk... Henry, my stupid rear end is 5:29 to 1 !! Now you know why I drove my Crown home from Fresno at 2200rpm going an insane 61mph!! Uck! A 20% overdrive took care of that though!! I must have the record on the world's worst rear ratio! It's great for tractor pulls though.... Cheers Gary | ||
| JD-Crown.GA (66.245.119.65) Rating: N/A |
I pull a 1993 Jeep Grand Cherokee Laredo with my 1968 Crown Supercoach 35 footer. 220 Cummins and a 5-speed Fuller. 3:70 Gears. It pulls it very well. Actually, I had 13 people on board, trunk full to the top with luggage and more luggage inside, and the Jeep. Still no problems and no overheating. |