More driveshaft guibo alignment problems..

[M3M3]

28 minutes ago, Dake said:

I'm going to get as close as possible and call it good.

better carry a spare guibo in the car.....

[Dake]

Don't get me wrong, I tend to be an extremely particular person, some might even say anal. I want this to be as correct as possible. But if I can get this fairly millimetrically accurate I'm probably going to call it good.

 

That's driven by an increasing suspicion that it wasn't right to begin with. I'd be thrilled to realize I'm missing something easy here. This is the first 02 I've rebuilt, after all. But the transmission mount and driver's engine mount are fixed exactly where they were before. That forces the passenger mount into one position regardless of whether or not it's adjustable. Unless tension is applied to the other two.

 

So my thought is that either my transmission bracket is wrong and has always been wrong, in which case I drove tens of thousands of miles on a misaligned guibo and had no problems, or I made some mistake or am missing something obvious.

[PaulTWinterton]

27 minutes ago, Dake said:

I tend to be an extremely particular person

 

Me too.  I've had the same situation with guibos.  The only thing I can add that hasn't been considered is the "settling" of the drivetrain once the car is back on the ground and driven.  Might or might not be fiction.

 

FWIW, my guibo has had a bit of distortion that I'm (almost) certain I could feel as vibration on take-off.  I put a 2mm washer under the rubber transmission mount and the vibration disappeared.  Again, you must confirm that the fan does not get close to the rad.  2mm lift at the rear of the tranny computes to more at the fan.

 

Still a good idea to carry an extra guibo, especially on longer road trips.

 

 

[TobyB]

So, yeah, a guibo can take a pretty high degree of misalignment and go a good distance.

 

The thin one is more tolerant, but even the chubby one will last longer than you'd expect

if it's really good quality.  What has happened frequently in the past is that the 

PO used a good guibo, but didn't get the alignment all that right

(as Marshall says, the trans looks wrong when it's right, fwiw) and the guibo lasted 40k.  New owner sees checking,

replaces with the absolute rubbish that's out there now, and the thing immediately dies.

 

"there's a problem!"

 

Well, yes, there are several, and supply of decent couplings is a big one.

 

Back to basics- build yourself a 'driveshaft checker' and do the alignment yourself.  It's not so hard,

and again, you'll find that the upper rear corner of the transmission really needs to be stuffed about 

1/2" into the tunnel to get everything dead- nuts.  Most of us shove it up in there until it rattles, then back it off

just enough so it doesn't, and the couplings last pretty well that way.

 

t

likes the thinner 3 bolt for this reason.  Also, you can still get decent ones last he looked.

[KFunk]

On 2/24/2020 at 3:36 PM, Dake said:

@KFunk and @jimk, I would tend to agree. I'm going to get as close as possible and call it good.

 

 

 

Wait... what?  Your conclusion is just to leave it as is?  Nooooo, I said just get a new mount from a reputable seller.

 

If you bolt it back together as is, that just puts you back to being one harsh clutch drop from having a very bad day.  You got very lucky it lasted as long as it did.  

[Dake]

I don't mean to imply that you're supporting the idea of installing it wrong. Just that it could probably go awhile with a slight misalignment. Emphasis on slight. FWIW, I don't clutch drop my car. A quarter second faster than slow is still slow ?

 

If everything I've said so far is true, then I can only conclude that my misaligned guibo lasted over 20,000 miles.

 

I don't want to leave it this way. It's a fact that the ideal driveline should be as close to arrow-straight as possible, but since the PO cut off the 4-speed mounting tabs I only see two ways to fix this:

• Slot the transmission mount hole and shove the transmission toward the driver footwell. Not only might this vibrate out of place, it puts constant tension on the transmission mount and passenger engine mount
• Slot the transmission bracket AND either
  • slot the existing passenger mount (not much room for that, not to mention IE rubber mounts are not slotted either)
  • purchase a slotted urethane passenger mount and plan on getting more dental work

If nobody has any other ideas, I'm going to do the latter and live with the mystery of how I made it 20k on a guibo with 4mm of inflection.

[dlacey]

13 minutes ago, Dake said:

 

If nobody has any other ideas, I'm going to do the latter and live with the mystery of how I made it 20k on a guibo with 4mm of inflection.

 

Thats what Guibos do....despite our perfect alignment in the workshop, the engine is moving around under power, the rear subframe is moving around under acceleration and braking...and even the bodyshell isnt perfectly stiff...the guibo is your compliance for all that non-ideality

[Dake]

1 hour ago, dlacey said:

 

Thats what Guibos do....despite our perfect alignment in the workshop, the engine is moving around under power, the rear subframe is moving around under acceleration and braking...and even the bodyshell isnt perfectly stiff...the guibo is your compliance for all that non-ideality

 

Well certainly to an extent, and you make a solid point by saying that the angle between the CSB and the transmission will change on a regular basis just from driving around. It's the home position it returns to that's of the biggest concern. The original sources I linked reason that the u-joint should bear the brunt of the home position misalignment by any means necessary.

 

And of course, unless I got lucky (which I rarely do), my badly misaligned guibo took me to multiple states over a 5-year period without a problem.

Edited February 29, 2020 by Dake

[KFunk]

Your luck may run out, depending on guiro built quality, like someone else was saying that there have been variations.  My original one withstood lots of abuse and non-existent center bearing damper (really just flopping loose), but when I started fiddling with it and tryin got to make it ‘better’, I just screwed it up and went through 3 or 4 guibos.  I am quite the abusive idiot though when it comes to driving, and regularly spin the wheels for fun and autocross.  Throttle-induced oversteer is most of the reason I enjoy driving the 2002, hah.

[Slavs]

I had to realign my driveshaft. It was a 5 speed conversion done, under the previous owner, by a  shop in Los Angeles using a kit. They just bolted the kit on without checking alignment. The misalignment resulted in vibration and a destroyed guibo. The kit is pretty robust and a pretty good design. It's just that the workers didn't take their time installing it.

[Dake]

1 minute ago, Slavs said:

I had to realign my driveshaft. It was a 5 speed conversion done, under the previous owner, by a  shop in Los Angeles using a kit. They just bolted the kit on without checking alignment. The misalignment resulted in vibration and a destroyed guibo. The kit is pretty robust and a pretty good design. It's just that the workers didn't take their time installing it.

 

What had to be aligned?

[Slavs]

In my case  the bracket was designed to bolt to the floor and trans tunnel vie 4 bolts. They just used 2 bolts, and the bracket sat too low by about 3/16". It also sat a little towards the passenger side. Even after bolting it to the chassis properly, it was still a little low, so I used a washer as a spacer between the transmission and the trans mount on the bracket. But, it still sat too far right. I slightly slotted the hole on the bracket to where  the rubber trans mount bolts. The problem with some of the kits is that the jigs they use to make them get misaligned. And, I suspect not all our cars are alike. I don't have a hoist, and it took some time resolving the problem. I slowly and incrementally raise the car with a hydraulic jack on to wooden blocks to a height of about 2 feet.

Edited March 1, 2020 by Slavs

[Dake]

That's really helpful, thank you. Sounds like the same process I'm using to align my setup. I have on good authority that the PO of my car threw it together overnight for a race the next morning, so I wouldn't be surprised if my car's transmission bracket (which is drilled into the floor) is either mounted in the wrong place or the transmission mount hole is wrong, or both.

 

I've decided to order an IE poly slotted passenger engine mount. I will then modify my transmission mount as necessary.

Edited May 8, 2020 by Dake

[Dake]

Update for anyone seeing this in the future. I figured it out. I installed the Ireland Engineering polyurethane passenger engine mount. It has slotted mounting holes similar to what you see on the cyclopticgaze post about a crooked engine. This allows you to pivot the engine a couple degrees. I had to use all the available movement but now the entire driveline lines up straight as an arrow. I considered slotting my stock mount but there wasn't much material left to slot. I would have had to hammer out the driver's side of the transmission tunnel if the PO hadn't already done that. Anywho, problem solved, thanks everyone for pushing me toward perfection.