satoh S650G engine changeablility ?

[rustydollar]

My flywheels are at the machine shop, the Mazda wheel is very thick. Both the Kubota and Mazda engines were internally balanced so interchanging the flywheels is a snap. just have to reposition the crankshaft holes and use the Mazda pressure plate and disk.

The Mazda gear case has been cast to position the starter on the RH side and you need to position your starter in the same location otherwise there would be no room for the Bendix gear to engage.

To re-purpose an engine just remember that all the bell housing bolts radiate from the crankshaft center, for those that know their geometry the layout would be a simple task.

My math skills suck, went this route using cheater disks to find my centers, then placed my marks using a transfer punch. Once the fist bell housing was marked out the seconed housing was doweled to the crank center.

Satoh front frame has a cross member welded with bolt holes that attach to the lower gear case housing the previous fellow who did this swap notched it out. I'll be grinding the welds free then re welding it into its new position as I'm using a full faced adapter plate.

He also ground some external ribs from the Kubota engine block to make room for the starter, I'm going to cant the engine 6 degrees to the right to allow for clearance with out destroying the future core value of the block should the need arise.

He also notched the frame to clear the oil filter, remote filter adapters are available for the Kubota.

Hydraulic lines have to be extended, rad moved forward.

Going with what little information given on the engine swap, my first adapter plate is a disaster. The new plate as I said will be full face with a repositioning and welding of the frame brace - no notching.

My cheaters that I used below to locate centers.

 

[rustydollar]

Once my flywheels are home will post pictures as you have asked, in the meantime the thickness of the flywheel and the distance the face of it fits into the Satoh 650G tractor bell housing will determine the thickness of your adapter plate.

The only problem with a thick adapter plate is that it will further distance your starter and bendix gear from making contact with the ring gear, you may have to recess the starter into the plate. No big deal any decent machine shop with a milling machine could do this for you.

If you end up using the Toyota flywheel just swap in the Satoh clutch disk and use the pressure plate from the Toy. Pilot bearing on the Mazda engine is machined to fit into the flywheel and not fitted into the crankshaft end.

My Kubota engine came from a mobile refrigeration unit commonly called a reefer, you want to find an early model made by Carrier the Thermo Kings used ISUZU engines. The latter engines may work as well.

If they sell frozen goods in Africa your in luck to find a diesel engine for your swap.

 

[rustydollar]

Hi all,
I am a new member and new owner of an old Satoh tractor...
I live in Richmond , VA and I have a family farm in Africa with a Satoh 650G tractor
Lately we have been struggling with starting the tractor/keeping it running even after installing a petronix ignition system...We never know if/when the tractor would start and it makes it so difficult to shcedule any repair.
I am seriously considering swapping the engine and I would like to gather some opinion on adapting a carburated 18 L Toyota 7A Engine as that is all we can find here...

RustyDollar, I truly appreciate the pictures and details you provided, and I was wondering if you could provide more picture of the tractor gearbox/clutch and on how you will attach the new engine to the old gearbox.
Much appreciated. Thanks

Before you swap that Mazda engine check the timing, perhaps the chain and gears are worn. Chalk the timing mark at both locations then use a timing light.

If when the timing light flashes the marks fluctuate from side to side from one another your timing chain is worn, with a good chain and gears the marks will hit dead on - appearing as stationary.

 

[rustydollar]

Very interesting engine swap gives an old Satoh S650G new life.

 

[mycricri]

Hi all, I previously posted our challenges with a satoh tractor that was shipped to Africa and we were considering installing a toyota 4A engine...
the 4A engine (except for one scarce version o it) is designed to be mounted transversely, we finally opted for installed the toyota 3A engine designed to me mounted longitudinally on the toyota sprinter carib or known as the toyota tercel 4x4 late 1980's early 1990 model.

Figued I would share some pictures o the ongoing work

 

[Lewjomo]

Hey I also have a 650g. I never had much luck with the original engine so I looked for a diesel alternative and found that with a few simple mods and an adaptor plate a kubota v2203 would be perfect. It is 46 hp and runs my 5 foot blower and 6 foot finish mower awesome.a little overkill but when is too much horsepower ever a problem! If you are interested in seeing some pics let me know. I also have a template of the adaptor plate I made.the complete refit took me about 40 hrs.

How can I get a copy of your template?

 

[rustydollar]

How can I get a copy of your template?

Andy used the indirect injected Kubota V2203 which was not mentioned in the original post, after purchasing the direct injected V2203 finding that it would not fit phoned Andy for further details.

No front engine mount was used engine hangs from rear adapter plate he ground one rib down on the block so the starter would fit as far as I'm concerned it's a cobbled installation.

He used the Satoh starter and welded the Bendix gear from the Kubots starter.

I have added the DI V2203 to a small collection of diesel engines stored in my shop for future projects and gave the Satoh away, and never want to see another one.

Making the adapter plate was simple enough, from the Kubots bellhousing had a center circle laser cut to fit the round hole that fit around the crankshaft drilled a 3/8" hole center then used transfers punches to mark out the hole pattern to fit the Satoh bell housing.

Andy used the Satoh flywheel and had the holes re-drilled to fit the Kubota engine, the machine shop uses an end mill, but once you get the flywheel back you'll notice the new holes overlap the Satoh bolt pattern.

Adapter plate bolts that are behind the flywheel have to be countersunk to clear the back end of the flywheel.

Like I said it's a cobbled effort.

This thread in its entirety should be removed as it's misleading.

 

[awhite3929]

How can I get a copy of your template?

Hey lejomo are you still interested in this adapter plate?

 

[awhite3929]

Hey guys sorry about the late response.here are some pics. Engine has been in for two years now and not one problem so far! I can cut a 2 acre lawn all summer on one tank of fuel! This mod really made this little tractor a great workhorse.

Well it's been 8 years since I swapped out the old Mazda. Recently I found a v2203 DI so I put that in. Huge difference in performance going from 2000 rpm to 2800rpm also built my own cab and bought a new Frontier blower.

 

[Volvoman]

Just found this thread today, and quickly focused in on the cab on your S650. Very nice job, as these tractors were not offered an accessory cab when new, and afaik no aftermarket manufacturers did either, with he possible exception of Original Cab offering a soft cab. Would you be so kind as to post a few photos showing more of it? Seeing your mounts and mount locations would be especially helpful to anyone wishing to make their own cab as well. I have a Bison S670D with the Mitsubishi K4D engine. For winter snowblowing, a cab would be worth its weight in gold! Are your cab windows made of Lexan?
Vvm