AC 920 diesel

[caseymou]

I looked at an ac 920 last night that was partially burnt. A brush fire got a little out of control and partially burnt some wiring and hydraulic hoses. I have no idea about the history of these tractors as I usually mess around with sears and john deere. I do, however, own a WD45 wide front which I am quite proud of and I would like nothing better than to have a matching garden tractor. Is the diesel engine actually a lamborgini engine? This tractor looks really nice (no signs of burning) and the hourmeter only shows 500 hours. Any ideas of value running and non running condition?

[UCD]

Chuck Hi welcome to the club. Yes it is a lombardini. It is a 790 cc 18 1/2 hp Diesel. I have had a 7790 for 18 years and I really like it. Some do some don't. I estimate mine has over 5000 hrs. on it and it still runs good. I tried out a 20 hp. gas Sunstar once and I kept the Diesel, it will run circles around the Sunstar. Nothing blows snow like a Simplicity or Allis Chalmers and nothing in those lines blow snow like a 7790 or 920. Some people say they are loud,smoke and shake. I don't think they are that loud and if you keep the injectors clean and a clean air filter they don't smoke. Mine shakes just a little when it first starts cold but I bump up the idle and it smoothes out. When it warms up it idles fairly smooth. Some people don't like the smell of a diesel. As far as what it is worth damaged I would say $400.00 to $800.00. One just sold on ebay for $800.00 with a mower deck, snowblower and a tiller. Just an Engine sold for over $700.00. I would not sell mine for $4000.00 Anything else you would like to know just yell. This & $1.00 might get you a small Coffee Maynard aka/UCD

[powerking_one]

Nothing blows snow like a 7790 or 920? Well I beg to differ. I don't think Simplicity/A.C. used or made any 2-stage blowers (I could be wrong)? Until you see a Gravely 2-wheeler w/28" MA-210 blower or a 4-wheeler w/38" blower in action, you ain't seen nothing! Tom(PK)

[caseymou]

UCD, Thanks for the welcome. I may just take you up on your offer for more information if I can seal the deal with this one. I have never worked on any diesels before so some of this will be new. I am power hungry and I thought 18.5 hp of diesel power could really put a smile on my face. I don't want to start any "snow throwing" about who can throw the farthest. Here in central Indiana we rarely see enough snow to warrant attaching a thrower/blower. Your site has already been a big help and I find it very easy to use and through. It's always nice to know there are others out there with similar equipment in case of questions/parts need.

[MikeES]

The 18.5 hp is understated. And the torque it produces...well. Last year we went head to head tractor pulling with a 7790 and a 917 with a strong M20 Kohler. The diesel usually won the pull. Good Luck! Mike S.

[UCD]

Tom The Shaft drive blowers on the Sunstar are 2 stage and the single stage on a 7790 will out blow it in light powder or heavy slush. I used a 20hp.Sunstar with a two stage blower for two weeks when I was thinking about trading. I kept the 7790 and glad I did. The 20 hp gas just runs out of power and the 2 stage just barely pukes the heavy stuff out. A friend had a rear 2 stage on a 25hp. Ford and I could run circles around him. I cleaned a 100' x 300' parking lot for 3 years and a 100' x 200' Parking lot for 15 years. Plus 6 drive ways and an apartment parking area all that that could not be done with a plow because there was no place to put the snow with a plow. I had snow banks piled higher than could be done with a bucket loader. I All so did about a mile of side walk between my garage and apartment building. This & $1.00 might get you a small Coffee Maynard aka/UCD

[LBS]

Yes, POWER! If you want it, you will have it with this. I bet I could beat any 25 HP Kohler with mine. If your crazy, you can turn the max fuel limiter screw out and probably get it up to 35 HP, just be sure to remember where it was so you can put it exactly back. You dont want to overheat it or burn any valves so keep the power bursts short! Oh yes, they sound great with the mufflers off! Then put a turbo on it and when your neighbor is trying to blow snow or mow tall grass with his JD go scare it into the weeds behind the barn! I'v done it, all except for the turbo, and its fun! Good luck! Lawrence

[dlcentral]

We use ours in stock king of lawn pulls[have to have deckand only 1 set of wheel weights] wins just about every time!I turned up top speed to 3850 on mine,BUT we use it around here for all chores so we want it to remain basically stock,,Want to see a Sim blow concrete type wet snow,,look in gallery,under Sim. at '3116?' pic,just dont BACK into anything with the G trac ,they are built like tanks,but will ruin flywheel,I've seen them even WITH the guard on with broke flywheels,,

[UCD]

This is Dave's 3116 Blowing heavy wet snow. Now add a diesel to that with it's torque and under rated 18 1/2hp. I had a 7016 and the 7790 does twice the job.

quote:

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Dave says "Who says single-stage blowers are no good? This is wet, heavy snow. And no, it's NOT for sale..."

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This & $1.00 might get you a small Coffee Maynard aka/UCD

[caseymou]

We bought it. Got to go and pick it up now. One concern we (dad and I) had was that the seller had used his big tractor to drag the AC out of the fire. I was afraid for the hydrostatic system but the seller told me that there was an automatic disengage system built into the seat? I'll post more after we work on it.

[caseymou]

Is there any type of 3 pt or pto on this tractor. The only time I have looked at it was in the dark and the tractor was in a field of weeds.

[UCD]

Chuck It has a center PTO that runs front center and rea attachments. As far as a rear hitch tthat was an option and don't know if it was included on your tractor. If you could post a picture of the rear of it we could tell you

[MikeES]

Chuck, as far as the hydro is concerned, there is a MANUAL disengagement UNDER the seat. Hopefully it just dragged the tires when he pulled it out. Mike.

[caseymou]

Thanks everyone for the repllies. We have the tractor home now and we have been repairing burnt wiring. Overall it's really not that bad. We had to make an air filter for it since the local NAPA didn't carry that. I think the electrical is done, all of the lights work, and the heater button (for lack of a better word) works and shows negative current draw when depressed. The gas was all drained out of the tank for a fresh replacement, the oil was drained, and the fuel filter was replaced. For now, we are using 10w-40 because that is all we had but it will be replaced with the suggested straight wt. before any hours are put on the tractor. We are looking for a manual for this tractor to get us any further as we are about ready to test fire it. We found the link to simplicity manuals and I know the 920 corresponds to the 7790 simplicity, but we were not able to access the manuals themselves. Any instructions on how to do this? Thanks again for everyones input. This forum has already proven to the the best resource for this tractor. There doesn't seem to be much info outside this site.

[caseymou]

Also, any suggestions for anything else we should try before attempting to start would be appreciated.

[UCD]

Chuck To read the manuals you have to download adobe acrobat reader it is free on the Simplicity site. The 10W40 oil is ok but make sure it is for diesel. I use synthetic oil. Run about 4 to 8 0z. of ATF or a good diesel additive like Cyclo in 3 gal of diesel fuel every so often to keep injectors clean. You can call Sandy Lake Implement http://simpletractors.com/sponsors/sandy_lake.htm E-mail sandylakeimp@hotmail.com telephone 724-376-2489 8-5 Eastern M-F or 8-12 Saturday, they are one of our sponsors and order the correct Air Filter. It is Important to have the correct one as a diesel needs lots of air to run correctly and a clogged filter will cause them to smoke. The replacement filter allso comes with a pre cleaner.

[gregc]

Hi Chuck, Here's some links that I think you're looking for. Operator's Manual Model 7790: http://www.simplicitytechpubs.com/6767PRINT/PDF_files/TP_100_3005_00_XX_S.pdf Parts Manual for 7790: http://www.simplicitytechpubs.com/6767PRINT/PDF_files/TP_400_1087_00_SV_S.pdf Service & Repair Manual for Large Frame Garden Tractors: http://www.simplicitytechpubs.com/6767PRINT/PDF_files/TP_500_973_01_SV_SMA.pdf Service Manual for 900 Series Lawn & Garden Tractors: http://www.simplicitytechpubs.com/6767PRINT/PDF_files/TP_500_3479_00_LT_A.pdf Save these manuals to disk, then if you have a CD burner, burn them onto a CD and you can print out just the pages that you want at any time and you can also delete them off your hard disk. (just a tip) Hope this helps you, Greg

[Dadsy98]

Welcome to the club Chuck! Greg, you beat me to it. I looked up the manuals and was going to post. I have a link here for the Simplicity dealers site. This site can be tedious to go through but, you won't need mfgr number for the equipment manuals. "100" series are operators manuals and the "400" and "500" series are service and parts. Steve http://www.simplicitytechpubs.com/v_techpubsearch.php

[Al]

Hi, Just thought I would mention, on these hydros, do not tow them in or out of bypass. This is for incidental movement only like 30 or 40 feet slow. If you tow this like a couple of blocks it will destroy the motor in the transmission. When the engine is not running the charge pump is not running and there is no oil in the upper case. The hyd motor in the hydro only has residual oil on the slippers. If it is towed very far, a couple of hundred feet will do it will destroy the motor. Even on a new unit Simplicity would not warranty a hydro with the motor torn up with the pump side still OK. Towing is the only way this can happen. If they pulled the tractor out of the fire should not have harmed it, in bypass or not. However if it was pulled very far you could have hydro problems. Good luck on this I am sure you will love the tractor. They have GUTS. Al Eden

[dlcentral]

Parts for these engs. are EXtreemly expensive,500 hrs is low mine is at 1400 I think,,If you think the 3116 throws snow wait till you see how this brute will do!,,Good luck to you!below,,the link will show you mine,,http://image.photoloft.com/opx-bin/OpxFIDISA.dll?s=cano&src=/PhotoLoft/Asset18/2002/02/22/9023/9023752_0_1827.fpx,0,0,1,1,512,384,FFFFFF

[caseymou]

Dad got it started Saturday. Only ran for a few seconds though. Lots of smoke. Also the bottom of the engine has a serious oil leak when the tractor is being turned over and when running. We haven't had a chance to check it out further. After draining the oil it looked funny like there might be something else mixed with it. Mabye water or fuel but no diesel smell. The original oil drained from the crankcase had just a little metalflake in it, hopefully nothing serious. I will try to get some pictures posted on this thread when I am next working on it.

[BradW]

I am not sure if these machines have bleeders for the lines or not, but make sure you bleed the lines if there are bleeders. If you don't you will experience poor running/lack of power and may crack a line. (I have seen it hapen, not something you want!) good luck -BradW

[UCD]

There is a manual fuel pump on the side of the engine to prime the lines. If this doesn'tdo it you have to crack the lines open at the injectors to bleed the lines. I usealy just loosen the lines at the injectors an crank it over till fuel comes out.

[BradW]

Thanks for the additional content UCD, hopefully now he will understand what I mean :) -BradW

[caseymou]

I gotcha about the fuel bleeding process. I will make sure to do that before anymore test running. With the thanksgiving weekend, we haven't had much time to get to the garage and work on it. Between the advice on the forum and the manuals downloaded from this site it has really made a difference working on this tractor. I might start looking for more Simplicity/AC stuff. I never knew there was this much following for them.