Lt1000

Sampleswow

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Hello all and Good afternoon,

I have a Craftsman Lt1000 using the old 31h777-0297 engine, and i need to replace it becuase that engine blew up completly like i mean connecting rod through the block, so i called B&S to try and find a replacement engine and the direct replacement is 900 dollars and thats a bit steep if you asked me i mean for about 500 extra dollars i could get a new mower, so im looking for any other suggestions on replacments, by doing some google research i found that this engine 31R977-0054 is compatitable but the wiring harness seem differnet and this is my only concern, if you guys could help me i would be greatly apperciated.
 

bertsmobile1

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For $ 500 more you could get a mower that will last 1/2 as long as the one you are replacing .
Go to the surplus engine wholesalers
Small engine warehouse
SMALL ENGINE SUPPLIERS
SURPLUS CENTER

Any engine with the same shaft diameter & length can be made to fit
Any B & S engine will be the easiest to fit because the controls will transfer from one to the other sa the mounts are the same .
Electrics same story off the old & onto the new.
Other brands can require new control cables and rewiring .

Bad time of the year to be looking for a new engine.

As for the 31R engine, check the shaft size length & type before you buy it.
The block will be the same as your motor so everything inside your old engine will fit as a worse case.
Different alternators , blower housings etc will give an engine a different number but the blocks are the sme so your old lternator will bolt onto it, your old muffler will fit etc etc etc.
 

Sampleswow

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For $ 500 more you could get a mower that will last 1/2 as long as the one you are replacing .
Go to the surplus engine wholesalers
Small engine warehouse
SMALL ENGINE SUPPLIERS
SURPLUS CENTER

Any engine with the same shaft diameter & length can be made to fit
Any B & S engine will be the easiest to fit because the controls will transfer from one to the other sa the mounts are the same .
Electrics same story off the old & onto the new.
Other brands can require new control cables and rewiring .

Bad time of the year to be looking for a new engine.

As for the 31R engine, check the shaft size length & type before you buy it.
The block will be the same as your motor so everything inside your old engine will fit as a worse case.
Different alternators , blower housings etc will give an engine a different number but the blocks are the sme so your old lternator will bolt onto it, your old muffler will fit etc etc etc.


Thanks for your reply although I have no idea what your talking about in your first paragraph,

In your last paragraph it seems that your answering my question what I don't understand is why would I swap the stuff from my old engine to the new one, I am buying a complete engine assembly everything but the exhaust included that's why I mentioned the wiring harness mismatch I was concerned about
 

bertsmobile1

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If Briggs made a 31h777 engine for 25 different manufacturers then there could be 25 different plugs on the ends of the wires because they are part of the mower not the engine .
This is where the 0297-B1 comes into play .
However the alternator from any 31??? engine will swap to any other 31??? engine so there is no need to worry about plugging it in.
IF it is not the same you swap the alternators and this the plug.
Add to that there are 5 different alternators potentially fitted to 31???? series engines
Add to to 3 different carburettors and a squillion mufflers or no muffler ( some are part of the mower ) .
However all of these parts have the same bolt mounts so you can swap anything that does not fit your mower from the old engine to the new .
I assumed that the object of the exercise was to get a replacement engine for the least cost.
I do this regularly for customers and advise them to sell all of the brand new bits I did not use.
A few of them got so much for the "wrong bits" the engine was nearly free .

AFAIK Briggs do not list what the engine to mower plug is . I certainly have never seen one .
I have seen NLA listed against an engine I was trying to replace when searching by engine number yet there were better than 50 variants still available that according to B & S would not fit
They all did it just takes a little more work .
Nearly all domestic mower engines have the same mounting centers so if it has a 1" dia keyed shaft 3 & 3/32 long then it can be made to fit
Thus you can fit an LCT, Tucmseh , Ducar , Loncin , Kohler, Honda, Briggs , Preditor, Kawasaki or any other shop branded engine ( Millers Falls, Rockwell etc ) into the hole in your mower , some will just take a bit more work than others but none are difficult to do.
However the Briggs will require the least amount of effort and all of the bits which might be part of the mower, like the muffler will bolt right on.

Briggs supposedly do a grab pack with interchange plugs to make this easier.
I have one ordered from 3 different suppliers that have been on backorder for over 2 years

I hope this clears things up for you
 

StarTech

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I have one ordered from 3 different suppliers that have been on backorder for over 2 years

That why I have ordered and stock the Molex and AMP TE Connectivity connector housings, pins, and sockets to do these conversions and repairs.

Now you need an open barrel crimper to install the terminals (pins and sockets) and the appropriate pin and sockets removal tools.
 

bertsmobile1

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Tar,
I will look into that
We seem to call thsese terminals different names down here but all of the auto electricans I frequent only carry plane blade terminals and just chop custom ones off
 

Sampleswow

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Thank you guys for all your help in resolving my concerns I'll pull the trigger on the 31R the shaft diameter is set to be the same on the motors so everything else is just swapping over thanks for your help
 

bertsmobile1

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Let us know how you go.
Should not be a big job
Hardest part is getting the !@#* engine pulley off.
And on that subject, put some anti -sieze on the shaft to prevent the pulley rusting on.
IS it a new engine or a used one ?
 

Cusser

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I have a 42" LT1000 purchased new in 2005 for $900. After a few years, it became tough to start, tough to get the engine to crank. I kept the battery on a tender, adjusted the valves as proper, etc., had battery checked/replaced. About 6 years ago one day while mowing apparently lost or used all the oil and engine broke, ruined. I bought a replacement B&S engine from an online supplier, engine had a couple more hp and it had a small spin-on oil filter. And the air filter was different. But this was a direct bolt-in and was easy to do, no modifications. And what is real interesting is that I have zero cranking issues, and no longer need to use the battery tender, and don't have to constantly monkey with the valves either. So in long run, this was a good deal for me as I no longer have those headaches I had with the old engine.
 
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