[risedrummer]

Hello, I recently purchased a 990 with a deck, blade, tiller and wheel weights off craigslist. It also came with a full set of manuals for the tractor, engine and implements. It has a 15hp Briggs engine with a Nov. 1971 manufacture date on it and has the three-bolt front wheel hubs on it. From what I have read, that leads me to believe it is a 1972 model year. I got a heck of a deal on it. It would barely run, was missing parts and needed help. First thing I did was install a new air filter and plug, and tuned the carb, now it runs great! I also replaced the front wheel hub bearings as two of them were broken and put on a set of R1 (technically I3) tires. It had truck tires on it when I bought it.The PO mounted a car battery behind the seat, unhooked the charging system, made some lift system modifications with a welder and a few other odd things here and there. She is definitely a work in progress, but what a great tractor this thing has been so far.

Next steps are finding an original gas tank (it has a 1 gallon tank off of some other machine) and correct oil dipstick, put the battery in the correct spot, rewire the entire tractor, adjust the motion control lever (it won't center properly and the tractor creeps), tighten the play in the front axle and adjust the governor. If anyone has a lead on a gas tank I'd really appreciate it. They seem to be very hard to find.

I know I will get this question, so I'll answer it here: The tires are a 7.6-15 Goodyear Sure Grip I3 tires. They are a little narrow for the rims, but I put tubes in them and had no issues mounting and seating them.

I'll post more pictures and progress when I have a chance to work on it. This will definitely not be a race to finish this tractor. Thanks for looking.

 

[VTXRider]

Welcome to the forum.
The 15hp was only offered for 1972.
You are already making good progress.
Where are you in Michigan? I have a gas tank from a 1973 990 to offer you.

 

[risedrummer]

PM sent!

 

[VTXRider]

Pictures of the tank. I have the straps also. If your engine has a dipstick, this tank will not fit.

 

[risedrummer]

A few more pictures of before/after changing the rear tires. These Sure Grip tires have an incredible amount of traction. They are ~30" tall, but still clear the fenders! I also replaced the old bolts with holes drilled in them attaching the three point lift arms with proper pins, and added washers to take up some slack.

 

[Lance Skene]

Welcome to the forum.

might want to keep those truck tires and chains handy if you plan on pushing snow, AG tires dont work well with snow/ice.

 

[risedrummer]

Small update on this old girl. I installed the fuel tank from Chuck (thanks again!) and everything seemed fine. I have been using it to spread and flatten fill dirt and topsoil for the yard I am installing. About a month ago, when pushing quite a bit of dirt, the engine bogged down and stopped. It took quite a bit to get it to start again. Then if immediately died again when I moved the travel lever. I was able to nurse it back into the garage. The next day, I tore the carb apart and rebuilt it. It was a little dirty, but nothing major. The tractor still wouldn't start until it had a little heat in it from turning over. I pulled the head and removed the 1/8" of carbon from the head and piston. Still nothing. I did a compression test and had a whopping 25psi of cylinder pressure. All that carbon I removed was the ONLY reason that poor motor ran. The piston wiggles back and forth inside the bore. I have never seen that amount of movement before. Looks like it is time for a rebuild. I have used the tractor MAYBE 10 hours. Oh well. I found a NOS engine base that has the oil fill in the base, so I can get rid of the dipstick, too. I guess it'll make for a good winter project. I need to rewire the entire machine, too. We buy these machines because they are heavier, stronger and better built than machines made these days. And because we like working ON them too, I suppose.

 

[risedrummer]

I am working on getting the engine off, and have a question. In the manual, it says that the driveshaft from the engine to the hydro pump can be slid off the engine to change the PTO belts. I took the set screw out from the engine side of the driveshaft (mine has a set screw and not a roll pin like I believe later models have) and tried to slide it back, but I noticed the shaft is solid, it is not two piece. So there is no where for the driveshaft to collapse on itself so it can be removed. Is the drive shaft supposed to be one piece? If so, how do I remove it to change belts in the future, without having to remove the motor?

Also, I am looking for a full generator bracket setup. Mine is mounted with a very cobbled, non-adjustable setup made from scrap steel. There is not much in the way of 990 parts on eBay, unfortunately. If anyone has one laying around they'd be willing to sell, please let me know. Pictures soon, I did not get a ton done today. Thanks in advance.

 

[VTXRider]

The front u-joint will slide on the shaft enough to slide off the engine shaft. Use heat and/or penetrating oil if needed to break the rust. Heat and cool with water a few times will break it free also. Should be enough room to get a pry bar in there to hit forward with a hammer. I had to file the shaft at the u-joint to get rust off so it will slide back. The rear u-joint is also suppose to be free on the hydro pump to slide.

I will look to see it I have a generator bracket.

 

[nojgib]

I am working on getting the engine off, and have a question. In the manual, it says that the driveshaft from the engine to the hydro pump can be slid off the engine to change the PTO belts. I took the set screw out from the engine side of the driveshaft (mine has a set screw and not a roll pin like I believe later models have) and tried to slide it back, but I noticed the shaft is solid, it is not two piece. So there is no where for the driveshaft to collapse on itself so it can be removed. Is the drive shaft supposed to be one piece? If so, how do I remove it to change belts in the future, without having to remove the motor?

The shaft is not one piece if it is original. There was probably a set screw holding the driveshaft to the engine, but there will be a pin holding the u-joint to the shaft. It will still most likely take lots of penetrating oil and patience.

 

[risedrummer]

I got the engine off. I could not get enough movement on the shaft to get it off without removing the engine. There is no roll pin; the joint is keyed to the engine and there is a set screw. As soon as I slid the engine forward, the joint slipped right off. First, what a MESS this poor tractor is. Wires everywhere, hacked up brackets, weird, mismatched bolts all over. Ugh. I cleaned the engine up and started disassembly. I have it down to the short block. I am hoping to get it to the machine shop this week to check/deck the head and block, bore the cylinder (hopefully only .010 over) and give it a valve job.

While the engine is away, I plan on relocating the battery to it's original position, rewiring the entire tractor, getting some headlights, hopefully finding a generator bracket, welding a broken generator ear, finding an engine PTO pulley (mine is missing a significant piece of on side), rebuilding/fixing/tightening the front end, clean, prime and paint engine sheet metal and clean and paint the front of the frame. Could use some front tires, we'll see how it goes. So far it's been going pretty smoothly. I am a little worried about finding parts for both the engine and the tractor itself. I can get oversized pistons from iSaveTractors, and I have found an undersized rod (hopefully I will not need one) elsewhere.

 

[VTXRider]

Are you looking for the double belt pto pulley or the front pto pulley that runs the snow blower?

I have the lower cast iron generator bracket and the rear pto pulley. PM me if you want them.

 

[risedrummer]

The double belt PTO pulley.

 

[risedrummer]

I picked up some spools of solid copper 14 AWG wire in the correct colors to rewire the entire tractor. I also picked up weatherproof, heatshrink terminals, a pair of headlight bulbs and a pair of new front tires.I hope to start building a wiring harness this weekend. I am having a REALLY hard time not tearing the entire thing down to nothing, cleaning, repairing and painting it. I just don't have the time to do that right now. Or the space. (It WILL be done in the future). If I do get after the wiring this weekend, I'll try and remember to get some pictures and post them.

 

[VTXRider]

Note: Solid copper wire is not normally used to do wiring. Stranded is flexible. Solid will break from vibration.

 

[risedrummer]

I should have phrased that better, sorry. It is stranded, pure copper wire. Not that 'copper-coated' junk that is being sold seems like every where. Most of the wire I was finding is aluminum coated in copper, and I have read that wire provides poor connectivity, and does not last nearly as long a pure copper wire does. I am not a fan of wiring, so I want to do it right the first time!

 

[risedrummer]

Does anyone know off hand if the starter/generator turns clockwise or counter-clockwise? I have everything apart and cannot turn the key to find out. I believe it is clockwise, but I'd like to be sure. Thank you in advance.

 

[VTXRider]

It turns clockwise looking at the pulley.

 

[risedrummer]

Both front tires were junk, so I figured why not replace them while I’m at it. Removed the old tires and found the previous owner filled the tires with some tire repair liquid and the rims were in bad shape. Major rust. I scraped the bulk off, sanded and painted with rusty metal primer, but I didn’t like how they turned out. So I threw them in the sand blaster cabinet and did it right. Primed, painted and mounted the new tires. I had to make spacers to accommodate the new larger tires. I went with 18x8.5-8 V61 rib tires.

 

[risedrummer]

Some pictures.