# Spirit 27" 8hp Tec to Pred 212



## cmi86 (Dec 19, 2019)

Got this machine recently thru an online private sale. ran good when we checked it out, started up nice when we got it back home, started right up a few days later and made 2 passes of the driveway before dying. Now has 30lbs compression and I am confident the valves are leaking. 

I'm a busy guy and have heard counless times of how swap and go these predator motors are, so after verifying crank dimensions and a little digging on swaps I went and picked up a 212 for $99 bucks on sale. 

Got the pulleys on to the new shaft and all looked like smooth sailing, until I went to put the 212 on the on the blower and it doesnt line up with the belts. Using the existing mounting holes for the Tec, the 212 sits back about 1-1/2" from where it needs to be. 

Some limited research shows that my Tec is a "big block" where as the 212 is a "small block" and while the mounting holes are dimensionally the same, their position relative to the engine as a whole is not the same. (pic attached)

Upon trying to research these dimensions online I'm coming up empty. Is the difference between the 2 a standardized layout or is it more case by case as far as location and alignment ? 

Also does anyone see any possible issue with locating the 212 properly and drilling new holes thru ? Self tapping or clearance thru and nut from the bottom side ? 

Thank you all in advance.


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## Oneacer (Jan 3, 2011)

Corrected photo position …..


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## Oneacer (Jan 3, 2011)

Some people grind off the old studs and drill and bolt the new engines on. Some need a longer stud, so they pop out the existing studs and replace them with longer bolts. ( I tack weld the heads of the bolts in the inside of the case, so they don't move upon setting the engine on _ or you can cut a plastic circle from a milk jug, punch a hole smaller than the bolt, and place it over the bolt to hold it in position while placing the engine on ) Then they also sell a plate that will bolt on (some make their own) and then have the correct bolt pattern for the new engine.

Many ways to do it.

Sample photo of what a pre-made plate might look like:

https://www.ebay.com/i/142456761563...MI99LI2PrB5gIVkcDICh2eIwaBEAkYEiABEgKLaPD_BwE


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## cmi86 (Dec 19, 2019)

No studs on this blower, holes that bolts run down thru the top of the mounts on the engine in to what I assume are probably nuts welded to the underside of the mounting plate. I am a machinist by trade so actually doing what I am going to need to do is nothing, I'm just wondering if there are standardized dimensional differences that I can reference and lay out or If I would jist be better off lining up the 212 where everything seems happy and drilling some new holes that way.


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## cmi86 (Dec 19, 2019)

Trying to avoid plates as it would elevate the engine, change the pulley position and I would assume require new larger belts as a result. Has nice belts already and trying to keep cost down.


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## toromike (Aug 20, 2018)

The 212 will be a direct fit for Tecumseh 5, 6, and 7 hp engines. It's normal when replacing an 8 hp and up with a 212 that a new mounting arrangement will have to be developed. Adjust the location of the 212 so that the pulleys line up correctly. Some people drill holes in the new position and use nuts and bolts, some drill holes, insert bolts/nuts from the inside and weld the bolts/nuts in place, some weld studs to the top of the transmission case, some make a mounting plate with welded studs and bolt the mounting plate to the transmission. When you drill new holes in the transmission case be sure to check for internal transmission parts that might be in the way of nuts or bolts. And when locating the 212, check for interference with the chute control rod, you might have to make some modifications but a small shift in engine location might avoid changes. 

[You might have to consider spacers to raise the 212 because the crankshaft height on the 8hp is usually higher that the 212 (so any idlers or clutches work properly). _edit: this statement is wrong, they are essentially the same_]


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## cmi86 (Dec 19, 2019)

toromike Thanks for the reply. Seems this is turning in to more work than even drilling some new holes and running some bolts. Upon realizing this I was considering the Pred 301 as the mounts and offsets would all be correct but that motor has a 1" shaft compared to my 3/4" shaft and would require sourcing new pulleys and that's a whole new mess trying to calulate all that out, it's also $140 more than the 212 lol.. Almost starting to look like a nice used or rebuilt Tec 8.0 might be the way to go for simplicities sake, as that was the whole idea behind the pred swap to begin with.


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## db130 (Feb 16, 2013)

I'm looking at page 18 on the 212cc Predator owner's manual and it lists the height of the center of the crank at 4.17 inches.

The typical 8-10 HP Tecumseh will have a height of 4.176" -> you should be able to account for the .006" difference in height without having to use new belts and whatnot.

I would use the mounting plate template that comes with the owner's manual and drill new holes to move the Predator 1.5" forward. I've attached a picture of it.

I usually mount engines using the "bolts from the bottom" method while using plastic strips to hold the bolts in place. Once the nuts are threaded onto the bolts, I pull the strips out before I tighten the nuts all the way down.


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## toromike (Aug 20, 2018)

Tractor Supply Company is a good source for reasonably priced pulleys. There are other sources, just ask and I'm sure you will get several suggestions.


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## toromike (Aug 20, 2018)

Well, I don't know where I got the idea that the crank was higher on the 8hp, I just measured a 212 and a tec 8hp and db130 is correct, they are essentially the same height. Thanks db130.


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## cmi86 (Dec 19, 2019)

Thanks for the help so far guys. Glad to know crank height is indeed a non factor ( at least I wouldn't imagine .006 would make much if any difference) so I can move on from that. Next question is if I use the provided mounting template and keep the new holes on relative center to the existing holes for the Tec, will the side to side position of the 212 crank be appropriate or is some degree of side to side repositioning necessary with the 212 as well ??


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## cmi86 (Dec 19, 2019)

Also, in regard to going in thru the transmission housing (I assume thru the bottom?) would one expect reasonable access to get some bolts thru or would there likely be more disassembly require to get enough space inside there ? I'm sure there are minor differences between makes and models but I would assume most drive systems are somewhat similar in layout and configuration ?


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## cranman (Jan 23, 2016)

On Ariens , the tractors are usually drilled for both sets of holes, small and medium blocks. What I would do on your project is to flip the Tec or Predator upside down, take a piece of thin cardboard like a cereal box, put it up against the base of the engine and tap around the base with a ball peen hammer to cut the cardboard and holes for a template. take the cardboard template, line it up with the original holes, draw a line with a sharpie on the back side of the template, move the template the required amount forward, and drill new holes. Put in the new bolts, or weld in studs and done.


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## toromike (Aug 20, 2018)

cmi86 said:


> Also, in regard to going in thru the transmission housing (I assume thru the bottom?) would one expect reasonable access to get some bolts thru or would there likely be more disassembly require to get enough space inside there ? I'm sure there are minor differences between makes and models but I would assume most drive systems are somewhat similar in layout and configuration ?


There can be major differences between makes and models. Transmission designs can be totally different, you have to figure out where you want the holes, then look inside. I have seen cases where an internal part blocked the desired position of mounting holes.


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## db130 (Feb 16, 2013)

Does your snowblower look like this?










If so, that's made by Murray sold under many different names. I had one that was branded as "Noma" that was also an 8hp 27" version.

I am pretty Murray made a 724 version of the same snowblower using the same back half of the snowblower, where the smaller engine was mounted closer to the front of the snowblower, so you should be able to drill new holes without running into clearance issues.


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## toromike (Aug 20, 2018)

cmi86 said:


> . . . Next question is if I use the provided mounting template and keep the new holes on relative center to the existing holes for the Tec, will the side to side position of the 212 crank be appropriate or is some degree of side to side repositioning necessary with the 212 as well ??


To minimize the amount of modifications, it's best to keep the crankshaft in the same position as the original engine. You can move it sideways a little if necessary to gain clearance for something like the chute control rod or to clear something inside the transmission case as long as it doesn't interfere with the idler/clutch pulley operation or the belt cover. You can move the engine more if you don't mind making modifications to idler/clutch pulleys, belt cover, possibly new belts, etc.


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## cmi86 (Dec 19, 2019)

Toromike That's what I was looking to do. I was just asking if there any design differences with the 212 that if keeping the new holes relative to center with the old holes would cause the crank to be out of position side to side ? Or if I keep everything lined up I should be good to go.


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## toromike (Aug 20, 2018)

cmi86 said:


> Toromike That's what I was looking to do. I was just asking if there any design differences with the 212 that if keeping the new holes relative to center with the old holes would cause the crank to be out of position side to side ? Or if I keep everything lined up I should be good to go.


 It looks like if you line up the mounting hole center lines the crank will be in the same position, at least according to this drawing (compared to the drawing in post #8)
https://www.smallenginesuppliers.com/html/engine-specs/tecumseh/hmsk80-110.html


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## cpchriste (Jan 19, 2014)

cranman said:


> On Ariens , the tractors are usually drilled for both sets of holes, small and medium blocks. What I would do on your project is to flip the Tec or Predator upside down, take a piece of thin cardboard like a cereal box, put it up against the base of the engine and tap around the base with a ball peen hammer to cut the cardboard and holes for a template. take the cardboard template, line it up with the original holes, draw a line with a sharpie on the back side of the template, move the template the required amount forward, and drill new holes. Put in the new bolts, or weld in studs and done.



In addition to the above, in my experience the welded-on engine mount tabs inside the tranny cavity usually have two holes: a forward position and a rear position. 

I suspect the holes in forward position will result in the proper placement for the predator. So you can thread into the forward tab hole and forego the need for nuts.
________________________________________________
Unrelated to above:
Are you sure that there's not a built-in compression release producing your 30psi compression results?
Your running problem may be something simple with no need to replace the engine.


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## cmi86 (Dec 19, 2019)

So finally got some time to dig in to this thing a bit more. Was able to open trans cover and see that indeed the holes I need are already there with nut welded , just senselessly covered up with a welded on motor plate that only has thru holes for the original location ? Seems senseless for the mfg to go so out of their way as to weld on a plate but oh well. Cut a few welds out, drill a couple holes thru the motor plate and I should be in business. Thanks folks.


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