Satoh S630D Runs Away!

   / Satoh S630D Runs Away! #1  

jpscotty21

New member
Joined
Sep 14, 2013
Messages
16
Location
Bulverde
Tractor
Satoh S630D Bull
Hello All, new to the forum and new to the Satoh world as well. I just picked up this ol' girl yesterday. Had been sitting in a barn for 10 years. The gentleman said that it belonged to his brother in-law who bought it new in the early 80's. Looks clean for its age, has almost 3800 hours on the clock. Supposedly they had new rings and rods done way back when before it got put up. It was strictly used for mowing as far as he knew.

Today I replaced the fuel lines along with a new settlement bowl, fresh fuel, bleed everything, had the battery charging since the night before. Gave her an official start crank and she started smoking immediately which was a pleasant relief. But, it sounded like one of the cylinders had low compression. Unfortunately I fried the glow plugs by accidentally leaving the key in the wrong position for a couple of hours the night before and did the same thing this morning. The glow indicator doesn't work and the PO by passed it. :mur: So I got my heat gun and aimed it down the throat of the intake and gave it another try.... OFF SHE GOES! I scrambled around to smother the intake quickly as I was prepared for a possible run away. I couldn't get it to respond no matter where the fuel lever is position up on the engine itself. I smothered the intake and allowed enough air for it to run slowly to warm up, after a bit I let it go and she got up to about 2600 rpm's, top operating speed according to specs. So I'm not sure what to pull off to look at what's stuck. Do these have a fuel rack or is it controlled through the governor? I guess on the left side where the fuel lever goes into the housing is where I need to explore? Its an odd setup that the fuel lever is on the left side of the engine and the injection pump is on the right? I'm guessing that's the governor on the left side. Anyone familiar with the fuel system on these things?

Bad news is I confirmed cylinder one is not firing and looks to have a blown head gasket. After messing with it some and she got warmed up, I was trying to determine the bad cylinder while it was running about mid speed. Next thing I know there's a 20ft anti-freeze geyser shooting from the rad (has wrong radiator cap). Shut it down and after everything clears and defogging my glasses, I saw and smelled just a whiff steam coming out from the intake. Tried it a couple more times and same results, steady gurgle when at idle after its warm and starts blowing over as the rpm raises. Also sounds like the intake valve may be sticking or is stuck on that same cylinder, it's popping the compression out of the intake fairly loudly. Other bad thing is that if you remove the oil cap while it's running and smothered, it takes off again. So its pulling a vac on the crankcase through what i'm assuming is the bad cylinder because of the stuck valve. Hope it's not too severe. Not hearing any knocking, clattering or any odd noises like something came loose. Hopefully just a bad head gasket and I don't mind doing some rings. Won't be looking forward to any machine work if required. Runs like a well lubed sewing machine overall though. Oil looks good and no signs of water or raw fuel. Didn't see any silver showing in the oil either, but I'll confirm that when I drain it. Sorry for the long post, but figured I would share my first start of this adventurous experience. I'm waiting for a shop manual but in the mean time i'm going to make a spot in the garage to start digging in. I'll post some pics of my progress along the way here shortly for those needing this kind of info. Hopefully I'll have some up tomorrow. Thanks y'all! :thumbsup:
 
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   / Satoh S630D Runs Away! #2  
Welcome

Sounds like you like adventures. :)

Keep us posted.
 
   / Satoh S630D Runs Away!
  • Thread Starter
#3  
Thanks Gale, I have had my share at my young age. What would life be without adventures? Hope someone that's been in one of these will chime in here before long. Plan to get a spot cleared to park her and start digging in tomorrow. Goodnight Y'all!
 
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   / Satoh S630D Runs Away!
  • Thread Starter
#4  
Good Morning guys and gals! I realized I'm going to have to "drive" this beast into the operating room. Problem is, i'm by myself out here. So if anyone has an idea that may be simple to unseize whatever it is that's fueling it to full speed I would really appreciate it. I'll be cleaning up the area this morning, so I got some time. I would rather get it under control before making the delicate move. The front tires are shot and i'm in a tight spot. So I'm having to take my time but, with the speed out of control and the coolant boiling out, it won't take long for it to over heat. Thanks again! :)
 
   / Satoh S630D Runs Away! #5  
I'd guess the injector pump is sticking. I had this happen with an Iseki that had been sitting for a while. Had the pump rebuilt.
 
   / Satoh S630D Runs Away!
  • Thread Starter
#6  
Thanks for the response Lens. Do you think the problem may very well be in the IP itself? I'm not familiar with the pumps on these two cylinders. I'm working on getting some pics up in a moment. Thanks again!
 
   / Satoh S630D Runs Away!
  • Thread Starter
#7  
photo 1.JPGphoto 2.JPGphoto 3.JPGphoto 4.JPGphoto 5.JPG

She's ready for some paint, but I think she'll do fine if I get'er up and going. Forgot to mention all the gears, ranges, pto, and hydraulics seem to be working and are sound. Just difficult to drive running on one tired cylinder.
 
   / Satoh S630D Runs Away! #8  
I'd guess the injector pump is sticking. I had this happen with an Iseki that had been sitting for a while. Had the pump rebuilt.

If possible I would run it on heavy Seafoam mixture if not pure for a few minutes and shut down. After doing it twice a day for a week you could test run again.
 
   / Satoh S630D Runs Away!
  • Thread Starter
#9  
I'll give that a try and might put something in the oil change, like marvel mystery. I'm killing some time waiting on a part to move the other project out of the way. Should be able to move the tractor in tonight to start tearing it down. I played around with it some more and it fired right off with the heat gun. I realized I had another moment. The vacuum in the crank case was from the valve cover vent connected to the intake horn. When I smothered it, it drew through there. :rolleyes: So did another check and no blow by what so ever, just a small even pulse as expected. In fact after letting run slow for awhile and keeping a close eye on the temp, it started smoothing out on that one cylinder quit a bit. Clean black smoke from the lack of air of course. No white smoke or oil burning at all. I went ahead and let it go again and I it appears the governor might be working. It went up to about 2700rpms then came down and settled right on 2500rpms. I tried putting a load on it by driving in a low gear and it seems to respond. After it started to get a bit warm I could hear the other cylinder start hitting randomly. I couldn't see much smoke, maybe a grey haze at full speed. Couldn't catch anything that indicated the other cylinder was firing off. The moment the cylinder started hitting the coolant began rolling over with violent air pockets. Sounds like it may just be the head gasket causing the lack of compression. The popping I heard from the intake has quieted a lot and goes away completely at a higher running speed. So the valve must be freeing up as well.
 
   / Satoh S630D Runs Away! #10  
Sounds like you are making progress. I have just started playing around with Marvel Mystery Oil myself but have been into SeaFoam in a major way since 2006 when I bought the 2002 Blazer with 102K miles on it. The local shop would not schedule me an appointment until after I ran a can of SeaFoam through the gas tank. The guy who has known me all of his life and our dads had worked together knew if my issues were just from a dirty fuel system/engine that I would be fine after the SeaFoam use and was. That sold me hard on SeaFoam.

The MMO testing has impressed me and should help free up any sticking valve, etc from build up setting for year.

While we had the 2002 Polaris 325 Magnum ATV in a non running state most all summer mainly due to having the fuel tank removed to adjust valves and replace rubber items we filled the crankcase with Marvel Mystery Oil to the full mark. We made up a loop of clear hose between the IN/OUT nipples on the base of the oil filter that go to the oil cooler, replaced the oil filter and flushed out the remaining motor oil in the oil pump system before completing the loop of clear hosing so no old oil was left anywhere. For weeks with the spark plug removed and carb off we would spin it for about 30 seconds with the starter each morning and evening on most days. For a few days before we started that we had the cylinder filled with MMO but the first time was with Sea Foam. I would sometimes forget to pull the plug and some would get pushed out the valves by the starter motor.

After about a month the MMO became more dull in color, not dark but just lost it bright clear red appearance. With the valve adjuster caps removed we could watch the MMO pumping and flowing back down into the crank case from the oil pressure created from starter only freely spinning the engine with the spark plug pulled.

By pumping the pure MMO through the ring grooves and all oil passages should have soften and flushed hard crud build up from over the years I hope. I had read many engines smoke/burn oil due to dirty ring groves causing the rings to stick in the groves leading to blow by. I read diesel engines with glow plugs are not too hard to get MMO, etc into the cylinders to soak the ring groves.

WARNING: We have to remember if an engine hits and a compressing cylinder is hydro locked something very important in the engine will break often. On a gas engine with no spark it may just lock the starter motor. Removing injectors in an old diesel engine can be a major task to add MMO I am sure.

You can soak your rings/ring groves while you have the head pulled. Keep us posted on what you find when you have it opened up.
 
 
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