Another crazy idea of mine ...

patooyee · Sep 28, 2008

So in preparation for my next buggy I've thought a lot about drivetrain accessability and how, in our efforts to cram more and more engine/trans/t-case into smaller and smaller packages typically reults in the drivetrain being pretty inaccessible. I know that pulling the engine out of my current buggy is a bitch and a half and requires gutting almost the entire interior, etc. Not to mention it is a huge mess of fluids, etc.

Here's my idea. What if one was to hard-mount their entire drivetrain to a full length very stout skid plate which then would mount to the underside of the chassis via poly bushings, several on each side and posisbly even some front and back. One issue would be resolved in that the drivetrain would have no way to twist torsionally without being an entire unit. Thus, no cracked trans tailhousings, t-case adapters, bellhousings, etc. Yet the passengers would still be isolated from drivetrain vibrations. The drivetrain could drop out the bottom of the buggy as a unit at that point and the buggy could be lifted/rolled off of it at which point the mechanic would have complete and open access to engine/tranny/t-case.

Here's the trick part of the idea. The whole design would be unitary as a concept. IE everything comes out and goes back in easily and as a unit with minimal fuss. Keeping this in mind, I thought about using some large industrial ball-valves, 2 per cooltant hose, that could be closed off to keep all the coolant from draining whent he drivetrain was dropped. Smaller ball valves could be used at every fluid line. (Trans, hydraulic, etc.) This way all fluids could be closed off when pulling the drivetrain and when it was reinstalled you probably wouldn't even have to top them off again as you would have almost no fluid loss.

Can anyone see anything wrong with this idea? I'm trying to think fo things that would have to be disconnected. All wiring could go through one large GM-style connector so that the engine harness could come out with the engine. Driveshafts are easy enough, too. Help me think of any flaws in my plan ...

J. J.

patooyee · Sep 28, 2008

Another cool thing would be that, sicne the skid plate would be integrated into the drivetrain assembly and poly-mounted it would absorb a lot of the impact to the passengers during those hard belly-outs. Also, if one designed it correctly, you could remove the side bushing bolts and pivot the entire assembly down just at the tail end using the front bushings as a hinge. That way the entire assembly doesn't have to come out if all you have to work on is the tranny / t-case.

J. J.

InDaShop · Sep 28, 2008

Links? Where you mounting the links? And would they not have to be removed to get the skid out? Maybe, maybe not?
Pretty decent idea. I am a fan of modular design. We have discussed quick disco's on lines (hydro, gas, etc. but it'd be easy to do it to all of them, right?

My buggy is the same. Everything has to come off to get to anything.

patooyee · Sep 28, 2008

Rear links would be on a really tough cross member. Haven't quite figured out the front yet though.

J. J.

draggbody · Sep 28, 2008

i know the parker store has some pretty slick "dripless" connectors... they work like a quick chuck for shop air lines but they dont allow any fluid to leak, or very minimal at best.... depending on front suspension, if you used a 3 link w/ panhard there would be nothing below the drivetrain as far as front suspension is concerned... i think trying to keep all of the hydraulic lines on the top of the chassis may induce some clutter, but all of the electronics could use OEM style connectors keeping the engine harness w/ the driveline....

thinking about it, just make sure the PS pump is easily removed and let it stay on the chassis, just like an A/C line does in a truck or car... just flop it over out of the way and leave the entire system hooked up... depending on space, you might integrate the tranny cooler beside the trans or something to keep from disconnecting it and of course the coolant is obviously got to come out....

patooyee · Sep 28, 2008

We have some gihugic ball valves on our fryers here at work that would work great for coolant so that it wouldn't even have to come out. If they're rated for hot fryer oil they'll work for coolant.

J. J.

blacksheep10 · Sep 28, 2008

if you mount on a skid, I can't see it working with a double triangulated setup well. Now, if you have a second belly that is like cole's old fireball (front and rear lower links converge on it, it unbolts) you can pull the links or lowers, jackstand, drop out modular powertrain, put 2 bolts back in teh lower cradle and roll away, I can see it. I don't think there are enough drop away belly pans outthere properly designed, they will work perfectly. I don't like the though of all of it coming out the top . **** that, at least with tranny/tcase.
you are doing it right with the respect to pre planning you exit points, even if its in 2 pieces (engine out the bottom is hard on any of them). On a couple of buggies I've been around, its pull the case, twist, cut this tube out, pull the range box, pull the tranny back, set it on link c member, pull out TQ, then drop tranny nose down vertical. **** a bunch of that ****.

patooyee · Sep 28, 2008

You could even put in a winch loop on the top of the cage at the center of the weight to run the winch rope through and lower it that way.

J. J.

wngrog · Sep 28, 2008

You could get a decent drivetrain that does not break all of the time :flipoff1:

patooyee · Sep 28, 2008

My drivetrain has never broken, really. The t-case seals started leaking so bad one time that I had to rebuild ... that was a bitch. Two tranny tailhousing bolts stripped out ... that was a huge bitch to helicoil in the rig also. My issue rigt now is that my belly is getting so badly bent of from all the pounding that it has bent the oil pan and caused a small leak which I'm sure will get worse over time. That will be a huge bitch. My tranny is also starting to slip which will be the ultimate bitch to remove and rebuild. With a modular drivetrain all of these would have been no big deal. But without it each time I had to take apart the interior and pull the engine/tranny.

J. J.

cicero · Sep 28, 2008

The way Ryan desinged the underside of my buggy the t-case is mounted on a removable 1/2 steel plate crossmember/skid and the motor and tranny come out as one unit in the front. Its a pretty simple setup.

rock mafia · Sep 28, 2008

wngrog said:
You could get a decent drivetrain that does not break all of the time

Ditto.

While not a bad idea, I think you are putting a little to much thought and effort into something you will only do a time or two.

patooyee · Sep 28, 2008

Actually, the reason I originaly thought of this was a packaging issue. One of the reasons that my current rockwelled buggy, while probably one of the lowest 5 rockwelled buggies in the nation, can't sit lower is because the driveshaft would hit the motor mount and belly skid mounts. No matter how you do it, at some point you're going to have this issue and I thought about what I coudl do to eliminate the one tube that goes from the motor to the frame and from the belly pan to the frame so that the driveshaft could come further up the side of the motor. I knew that that mounting tube had to be moved and really even that method was kind fo cumbersome for mounting the skid plate. Thats when I thought of this. With this idea you can make a skid plate that hugs the bottom of the engine more tightly and attaches directly to the engine. Then you can mount the skid plate anywhere along the length of the drivtrain that you like. So you can mount it in front of and behind where the driveshaft would hit instead of right in the middle where it is the worst and where the motor mount typically always ends up. I know that in my current buggy I could have made it sit roughly about 5" lower by using this design. (I'm all about low COGs. Ask my friends, I'm neurotic about it.)

J. J.

Woodlee · Sep 28, 2008

JJ using engine plates will help this problem with the drive shaft hitting there.

Woodlee · Sep 28, 2008

cicero said:
The way Ryan desinged the underside of my buggy the t-case is mounted on a removable 1/2 steel plate crossmember/skid and the motor and tranny come out as one unit in the front. Its a pretty simple setup.

I broke a ton of transmissions with a set up just like this. The 1/2 plate will bend and break the transmission case. I like your build and I'm just trying to help steer you away from a problem.

cicero · Sep 28, 2008

Thanks, the tranny has a poly mount between the tranny and the plate. the tranny is positioned to the front of the crossmember. Hope that doesn't happen!!! thanks for the help!!

patooyee · Sep 28, 2008

Woodlee said:
JJ using engine plates will help this problem with the drive shaft hitting there.

Define engine plate ...

J. J.

Cole · Sep 28, 2008

patooyee said:
Define engine plate ...

J. J.

This is what he used when he mounted my 8.1l in my old jeep. Runs between the motor and transmission all the way to both sides of the frame or Chassis.