Space the TQ Driver or move the sprocket?

[jamyers]

I know this has been addressed here, but apparently my searchfu is weak tonight...

Got a Yerf-Dog 320? with a blown Tec and a Comet 30 TQ. Picked up a HF Predator on sale. Rebuilt and cleaned the Comet TQ. Go to mount everything up, and I either need to put some spacers behind the TQ driver to move it farther left, or I need to move the chain sprockets (Axle and Jackshaft) to the left of the TQ driven.
Below is a pic of the engine, TQ driver, and jackshaft sprocket as they'd "like" to sit currently.

I'd generally have no problem spacing the TQ driver out, only it's already hanging out past the end of the crankshaft.

I can't see any functional reason not to move the chain sprockets to the left either, unless doing so would put too much load out on the end of the jackshaft, and/or (likely) the axle keyway isn't cut long enough to move the axle sprocket over.

Or do I have something backwards or otherwise terribly wrong?

 

[OzFab]

I've seen this before. IIRC, it's because the tec output shaft is longer than the predator shaft so, not really much you can do there, the sprockets will need to move.

Will moving them to the left create a problem with the driven? If not, do that but, the jackshaft will need to be attached to the outside frame for support

 

[landuse]

Is your jackshaft just hanging out there with the sprocket on it, or is it supported somewhere near your jackshaft sprocket? From the pic it looks like the jackshaft has no support where the sprocket is now.

 

[jamyers]

Yup, the Tec crankshaft is longer than any of my other engines (briggs, honda, subaru), which are all the same length. Guess Yerf-Dog specified special cranks? I'll get some measurements on how much wider the TQ driver is than the crank - this whole thing sure seems odd, since I see Comet 30's on lots of engines other than Tec's, and they all have the jackshaft sprocket behind (to the right) of the TQ driven...what's so different / special about Yerf-Dogs?

Sorry about the poorly-explained pic, the jackshaft in the pic is laying on the frame behind (not installed) it's bearing housing, which is just in front of it (*right* up against the engine, as if nobody needs room to get a wrench in there, grrr...) When it's installed, it'd have a lot of support to its right, but if I move the sprockets to the left of the driven unit I'll prolly need to add a support/bearing out at its left end (assuming the jackshaft is long enough or I'll need a new one).

I'm sure somebody here has done this before with pics, I just can't figure out who...
(wanders off to try searching again...)

 

[jamyers]

AHA! After a 4th cup of coffee, my SearchFu has returned!

Search: Keyword(s): yerf, shaft ; Posts Made By: Blazkowiez
http://www.diygokarts.com/vb/showthread.php?t=7948&highlight=yerf+shaft
http://www.diygokarts.com/vb/showthread.php?t=9174&highlight=yerf+shaft

The "Money Quote":

Jason, on Yerf-Dog engines these had a spacer which was approx 3/4" wide by 3/4" bore, the shaft on these engines Yerf-Dog ordered had longer shafts to fully accommodate these torque converters. You'll need a 3/4" spacer to move the backplate out on the shaft, the back plate will go on fully and reveal only about 1/4" remaining on the shaft to put the hub/main section of your drive clutch on. That 1/4" is just fine for supporting the remainder of the section because unlike standard chain drive clutches, this hub is a solid piece, the only thing you'll need at this point is a longer 5/16 fine thread bolt large washer and lock washer to hold this together.

Looks like I'll be ok spacing the TQ driver unit out from the engine, according to Blazkowiez and his experience.

I'll get some additional pics once installed and post results.

If I pulled it this Yerf-Dog Engine-Swap stuff all together into one post, could it become a sticky?

 

[landuse]

If I pulled it this Yerf-Dog Engine-Swap stuff all together into one post, could it become a sticky?

I am sure if it is good enough we would definately have a look at it. Even if it doesn't get stickied it would be a great source of information

 

[CUCUY]

AHA! After a 4th cup of coffee, my SearchFu has returned!

Search: Keyword(s): yerf, shaft ; Posts Made By: Blazkowiez
http://www.diygokarts.com/vb/showthread.php?t=7948&highlight=yerf+shaft
http://www.diygokarts.com/vb/showthread.php?t=9174&highlight=yerf+shaft

The "Money Quote":


Looks like I'll be ok spacing the TQ driver unit out from the engine, according to Blazkowiez and his experience.

I'll get some additional pics once installed and post results.

If I pulled it this Yerf-Dog Engine-Swap stuff all together into one post, could it become a sticky?

yup, i ended up making my own brass bushing here at work instead of adding washers and making it look all ghetto. came out very nice and haven't had any problems yet.

 

[jamyers]

I used a steel bushing I picked up at an old-school hardware store, but I think a piece of 3/4" iron pipe cut to length would be just as good, and $1 cheaper (assuming you've got 3/4" pipe laying around...)

I've got a ton of pics of the install, just need to sit down and upload them

Kart is running like a champ!