Briggs Vanguard 6HP TaV mounting issue

[Tigersaber01]

Ok... Finally got ALL the parts, got the kart all put together, (with a brand new 40 series TaV2), and went to take a test ride. Went 4 feet...

Got the kart back in the garage and take a look, to find my TaV2 has come loose. All four mounting bolts have pulled out of the block. And it appears that they were only about 4 threads into the block, even though they were torqued down.

Now, I am getting longer bolts tomorrow. My concern is this:

1.) There is a lip on the crank cover, around the output shaft, that prevents the TaV2 backplate from seating flush to the crank cover.

2.) I don't want vibration to cause this problem to recur.

Should I use spacers between the backplate and crank cover?

Or should I try to mod the TaV2 backplate to fit around the lip?

 

[Brianator]

I may not be the right person to pipe in on this but I'll give you some food for thought...

- I avoid using spacers in high stress applications as they're basically impossible to stop from shifting around. Unless it's a large spacer(s) that provides alot of surface area around the lip and bolts holes I see more troubles ahead.

- If modifying the backplate would create any sort of notch in said backplate then thats not a good option either as it would considerably weaken it.

- If removing the lip on the crank cover wouldn't cause any overcomeable clearance or alignment issues then that feels like the best option, that lip adds rigidity to the cover but the backplate bolted securely to it would add much more than would be lost.

- Blue loctite is your friend.

Someone please correct me if I'm way off base here, I'm not super familiar with your powerplants and the nuances involved.

 

[itsid]

?? tav2 is series 30.. there is NO tavkit for a series 40 at all..

there's a "third party" backplate for a series 40
(which IMHO is the worst possible idea to mount one)

And since the "loctite" would've been my answer here as well..
I'm curious enough to ask for a pic of your TC

'sid

 

[Tigersaber01]

?? tav2 is series 30.. there is NO tavkit for a series 40 at all..

there's a "third party" backplate for a series 40
(which IMHO is the worst possible idea to mount one)

And since the "loctite" would've been my answer here as well..
I'm curious enough to ask for a pic of your TC

'sid

I got this TaV unit off of wish, so it's definitely a third-party/knockoff. I'll post a picture in a couple minutes. I'm about to head out to the garage to take it apart so I can take one of the bolts with me to Home Depot.

Unfortunately, I don't have the tools to machine down the lip on the crank cover. Plus, that lip seems to also be holding a seal.

I have to get this kart done and out today to make room for the new kart I just picked up.

I just got a Murray Explorer that's been modified with a much bigger engine and torque converter. I'll post pictures of it soon too.
•MERGED•
Here is the kart in question, and the offending TaV unit.

 

[Brianator]

That indeed looks like a 30 series TC. I wouldn't mess with the lip based on what you've said.... could you give us a close up of the crankcase cover and lip/seal area while you have it apart?

 

[itsid]

yepp, series 30 for sure. good to know (the much better choice for you than a series 40 anyways )

Now.. once you remove the TAVkit from the engine, would you mind to take a pic of that crank case cover for us please?
because the ones I remember are almost perfectly flat..
and that lip the bearing is seated in actually fits into the round cutout in the TAvs backplate...
So I'm curious why yours stands off by an inch almost

longer bolts bight do the trick, but do not use nuts to fix them..
instead use standof nuts (longer than you need and then cut to fit perfectly)
and since that will most likely still tend to vibrate,
use a few small strips of flat steel and weld them between the standoffs to form a rigid
frame.
(OH: it's best to drill ot the standoffs to make them just spacers.. easier to mount that way )

Or if that fails.. cut the aluminium backplate of the tav rather than the crankcase IMHO..

'sid

PS but first.. let's try to get that backplate flush with the crankcase cover )

 

[Tigersaber01]

Thanks for the replies. Didn't see this in time to get pics with the TaV off.

I did end up reaming out the hole on the TaV until it fit around the lip on the crank cover.

The engine came off of a rototiller. Just FYI.

After careful and gradual sanding, (took an hour), it fit like a glove and bolted up beautifully!

I'll be returning to this cart and doing some rework before too long. This was my first kart project in over 20 years, and I have been using it as a learning platform. I have a 7HP electric start Tecumseh engine I want to put on the kart, and I'll probably have to redo the spindle brackets, if I can't stabilize the steering with an alignment.

When I do the rework, I'll be saving the B&S engine for a minibike or something.

 

[Brianator]

Good work man! Team's proud of ya! Lol