Author Topic: '70 Mini - Rust repairs to Daily Driver (hopefully)  (Read 22314 times)

Offline Bahowe1

'70 Mini - Rust repairs to Daily Driver (hopefully)
« on: January 04, 2017, 01:48:55 PM »
Introduction:  Hello!  I have read many of your posts and gotten inspirations from lots of you and now it is time for me to finally do what I have never done before... mini bodywork.
I bought this mini as a huge project - a í70 mini.  The previous owner had actually started to do a Honda swap in it.  He had basically cut out the needed parts, put in the subframe, and the Honda engine, and put it up for sale.  I bought it, made a wiring harness and everything else that it needed and completed it so it would run.  I drove it like this for about 2 years, but when I could look around while sitting in the driverís seat and see the ground whooshing by in about 15 different spots, I decided I finally need to tear it down and completely go through it from the ground up before I occasionally fit my family in there with me.  So far, I have completely rebuilt the engine and tranny, including re-gearing and putting in a limited slip diff.
Just getting started on bodywork and need to call in professional help (you guys).  I need to do full floor replacement, flitch panel replacement, and a ton of stuff in between, but this is where I am starting and my immediate questions.   Eventually, I will be touching about everything from the floor pan to about 3 inches up the body.  After completely sandblasting it, it was clear that someone has already put a ton of patches on this car.  They basically welded a good piece of metal overtop rust.  I hope to fix all that.  But it makes it a lot worse when trying to cut out pieces.
I am using Magnum replacement panels and opted for ordering quarter pans to save shipping.  Half pans and full pan were nuts to ship.  I notice they gave me a bit more material than needed, so i have a choice of where I should have my weld seam break.  ??Should it break on one of the flanges of the box cross member?  Or do you have it break in the middle of the box cross member??
Also, I am getting ready to cut out for a full flitch panel replacement.  To get the alignment correct, ??do you guys bolt it using the hinge holes for the doors and assume that alignment is correct??  Or do you get out the a-panel and mock fit it and then the door, ect??  (See picture)  If so... how do you do that?
Also... ??what tools are you guys using to grind welds in tight spaces??  Example, the PO welded in a new floor, they just put the pan on the inside and welded it on top of the old one.  I want to cut call that out and do it correct, but I donít know how to cut out the last little remainder of the floor where it is in the corner caused by the tunnel and cross member? (See picture)  I have a 4 inch grinder... but like tools.
Last question... for this post...  Both the flitch panel and the floor pan have flanges.  ??Should the flanges of the flitch be on the outside of the floor pan??  It sort of seems like the flitch panel is too tall, meaning it looks like the floor runs at an angle back to the cross member.  If I put the floor on the inside, it seems like there will eventually be too large of a gap with the outer sill.  Thoughts?

Pics attached, one picture of what she used to be... and will be again... but better.

Offline jedduh01

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #1 on: January 04, 2017, 01:53:13 PM »
Hi Ben ! Welcome

Offline MiniDave

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #2 on: January 04, 2017, 02:14:38 PM »
Welcome Ben!

I have questions about changing the final drive gearing - which Honda do you have? D series or twin cam?

Dan will be along shortly to help with your body questions...

BTW, where are you located?
1989 Cooper Racing Green
2009 Clubman S
1969 Jaguar XK-E FHC
2004 Audi Allroad 2.7 TT

Offline Bahowe1

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #3 on: January 04, 2017, 02:29:48 PM »
D series.  I had the 4.25 f/d.  Ended up putting in the 3.722.  It should put it back closer to what the Civic car would have been expecting with Honda15 inch wheels.  I am running 13's so its about 70mph 3100 rpm, vs what it used to be - 3600 for 70rpm.  I am located in the Charlotte NC area.

Offline MiniDave

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #4 on: January 04, 2017, 03:10:50 PM »
I have a friend with a D series who's thinking of changing his, and trying to decide on the 3:72 vs the 3:54 considering how light the car is I'm thinking it would pull the even taller gears really well, and quiet it down considerably.

Where did you get your gears and gaskets/seals? How did you pull the engine, drop the subframe of pull the motor out the top?

I just got home from NC (Asheville area) and my grandson goes to college in Charlotte......



Doesn't this damage the roof panel?
« Last Edit: January 04, 2017, 03:13:04 PM by MiniDave »
1989 Cooper Racing Green
2009 Clubman S
1969 Jaguar XK-E FHC
2004 Audi Allroad 2.7 TT

Offline 94touring

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #5 on: January 04, 2017, 03:26:23 PM »
Where you join the pans is really up to you.  No right or wrong place there.  The door closing panel I always bolt to where the door mounts and take it from there.  The lip of the closing panel goes over (outside) the pan along the bottom.  When you go to fit the apanel you may discover it doesn't extend far enough for the lip to fold over the door closing panel, at which time fit doors and trim the excess off the closing panel.  Aside from an angle grinder I will use a dremel or grinding bits in my drill for tight spots.

Offline Bahowe1

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #6 on: January 04, 2017, 03:35:55 PM »
Ha!  Jedduh (Justin) has been helping me on this project... he chimed in with this picture... and also is responsible for building the awesome roof rack which the car is sitting on.  Look carefully.  It is sitting on a roof rack, so the top is not actually taking any weight (weight is transferred through the roof rails). 

To pull the engine in this setup is pretty simple.  Unbolt the subframe, disconnect everything, pick up the front of the car and push is back over the engine/subframe package.  My brother and I did that one by hand.

When you change final drive, you change it and the countershaft.  I got my gears and countershaft from Synchrotech.  While in there, I did bearings, seals, synchros, synchro springs, diff bearings and sleeves (basically made it new).  Synchrotech can sell you all that.  And it is good quality parts.

I'm not aware of a 3.54 option for f/d.  (I'm no expert either though) I was thinking my next option for larger fd was 3.250.  I was initially shooting for it, but they are hens teeth, and I am sort of glad I got what I have (not that I have actually driven it since the rebuild). 4.25, 4.058, 3.888, 3.722, 3.250 are the options I knew of.

Offline Bahowe1

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #7 on: January 05, 2017, 05:24:39 AM »
Dan, thanks!  Got it.  I'll start with the closing panel and go from there. 

Offline Bahowe1

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #8 on: January 09, 2017, 07:42:23 AM »
Happy Monday!  Most of my posts will probably happen on Monday.  I have three small kids, so I usually get Saturday afternoon to work on the mini (not much more, sometimes less).  Made some progress... Flitch panel is welded in, front quarter pan is tacked in. 
With a little beating and wiggling, it looks like alignment is ok, thus far. 
My next step is preparing for rear quarter pan, but to do that, I will need to repair the rear subframe mount panel.  I have a partial rear subframe repair piece (about 8 inches long or so).  I've included pictures of my progress, and the areas I will be tackling next (looks pretty rough).  I think my plan of action is to cut out most of the pan on this side I am working on, then cut out the part of the rear subframe mounting panel.  Then cut out and weld in the closing panel that goes in front of the rear wheel arch, then weld in the subframe mount panel repair piece.  Once I get that set, I think I will cut off the bottom of the rear quarter panel all the way back to the rear wheel arch (I have a repair panel for that section).  That will allow me to cut out the rest of the floor pan so I can then weld in the rear floor pan.
If I am thinking or going about this wrong... please help.  I'll take any and all help... this is my first go at anything like this (at all)!!
Also... does anyone have a picture of the underside rear area where I am working?  I can't understand what closes off the rear bin.  Nothing??  A picture looking from rear wheel area back toward subframe mount panel.  Looks like a big gap opening to bin.


Offline 94touring

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #9 on: January 09, 2017, 08:11:32 AM »
Your photo looking up to the bin is correct, there will be a factory gap there.  When you go to fit your subframe attach patch panel, mount the subframe, then slide the patch panel in place, bolt it to the subframe, tack it in place, remove subframe, and finish welding it in place.

Offline Bahowe1

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #10 on: January 16, 2017, 07:10:16 AM »
It's another Monday.  I didn't get to work much at all on the mini this weekend.  Over the Christmas holiday my real daily driver blew a coolant hose and ultimately compromised the head gasket - 92 Toyota pickup.  This weekend I needed to do the deed, new head gasket, so not much mini time.
My good buddy Jedduh01 came over to lend a hand.  Speaking of Jedduh01, if any of you guys are around Charlotte area and have a mini project (or about any other car ) that needs to be knocked out...  Jedduh01 is the man.  Anyways...
I did manage to get the rear (one side) floor cut out as well as part of the rear subframe mount.  I'm sort of wrapping my head around how it all should go back - right. 
Dan, thanks for the advice about using the subby to get my panel in place.  Good thoughts.  It would really stink to get it all welded up and the bolts not fit!
I think my next steps are to cut out where that closing panel goes in front of the rear wheel arch (area between arch and subframe mount).  Get that panel welded in, then using the subby, get the repair suframe mount piece in, then the floor.
Pics below.
Oh... and... anybody have some wheel arches?  Looks like I didn't order (but should have) wheel arches and the support for floor to wheel arch (in the boot).
   

Offline 94touring

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #11 on: January 16, 2017, 09:35:51 AM »
You need a rotisserie!  Looking good though  77.gif

Offline John Gervais

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Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #12 on: January 16, 2017, 04:57:56 PM »
Definately got bigger balls than I do -  77.gif
- Pave the Bay -

Offline Bahowe1

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #13 on: January 17, 2017, 06:49:57 AM »
A rotisserie would be nice!
John, I think I was more gutsy when I was ignorant.  I drove this car pretty hard during some of the mini meet up events.  As I look at all the places with rust flakes in place where there should have been metal, it makes me thankful nothing serious happened. This part of the process though is not so bad.  Basically cut some stuff out and ask Dan what to do!  Ha!
Hopefully when I get to parts where it actually needs to look aesthetically pleasing, I can do half as good as some of what you guys on here have done. 

Offline Bahowe1

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #14 on: January 18, 2017, 05:11:49 AM »
Here's a shot of the engine/tranny package that I rebuilt... just sitting there... ready to go!

Offline MiniDave

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #15 on: January 18, 2017, 10:09:01 AM »
Gonna grind that Honda emblem off the valve cover? I like the Morris green engine block  ;D

Looks like a MiniTech frame, are those tow bar brackets welded to the front of your frame?

I'll bet you wind up replacing those red poly motor mount bushes for stock mounts, the car will buzz and vibrate like crazy with those - we changed Don's the first week he had it, took 50% of the vibes away.

This is my buddy's P'up, he's done over 25K miles in it since he got it freshly built at MiniTech....I've done all the work on it since.

« Last Edit: January 18, 2017, 10:14:37 AM by MiniDave »
1989 Cooper Racing Green
2009 Clubman S
1969 Jaguar XK-E FHC
2004 Audi Allroad 2.7 TT

Offline Bahowe1

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #16 on: January 19, 2017, 12:59:18 PM »
@MiniDave - good word on the motor mounts.  I hadn't really thought of that.  I did drive it for a couple years before this tear down and it did vibrate (and rattle) a good bit, but I always chalked it up to being a car barely holding together.

The valve cover color will probably change to match the body color - once I get there.  yeah, I might shave it off then.

Those are tow brackets welded to the frame.  I towed over to the CMU event after I got it built, wasn't sure if it'd make the 'shakedown'... it did.

That's a good looking conversion.  They do good work... but are expensive (for me).

Offline MiniDave

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #17 on: January 19, 2017, 03:50:58 PM »
The reason I asked about the brackets is that I've been trying to figure out how to do some for Don's Pup.....the radiator side is the hard one, if you have some close up pics I'd appreciate the input!

MiniTec ARE expensive, no question. I've since built him an exhaust header and done a bunch of suspension and other work, the car has really been reliable for him as evidenced by the smiles he's driven in it.
« Last Edit: January 19, 2017, 03:52:49 PM by MiniDave »
1989 Cooper Racing Green
2009 Clubman S
1969 Jaguar XK-E FHC
2004 Audi Allroad 2.7 TT

Offline Bahowe1

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #18 on: January 19, 2017, 04:11:09 PM »
5000 lb adjustable tow bar at harbor freight. Like $70. Take off the brackets and weld them to the frame.
The harbor freight set up allows a lot of flexibility for where you mount because the tow portion has lots of swivels.

Offline MiniDave

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #19 on: January 19, 2017, 04:20:21 PM »
Yes, I have one of those too - I spotted yours back in the corner there.......I built a bracket to attach to the car and the HF bar attaches to that.
1989 Cooper Racing Green
2009 Clubman S
1969 Jaguar XK-E FHC
2004 Audi Allroad 2.7 TT

Offline MiniDave

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #20 on: January 21, 2017, 06:36:58 PM »
How did you handle your intake manifold?

Some guys cut a chunk out of the bulkhead for clearance, some guys cut the intake runners and use silicone hoses to hook them back together....

Did you cut back the lower valance to clear the tow bar brackets? Dan has a tutorial on building a tow bar for Minis under the "DIY" heading at the top of the forum page. I used his as a base but modified it for a clubman front end - mine will work with either car.
« Last Edit: January 21, 2017, 06:39:20 PM by MiniDave »
1989 Cooper Racing Green
2009 Clubman S
1969 Jaguar XK-E FHC
2004 Audi Allroad 2.7 TT

Offline Bahowe1

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #21 on: January 22, 2017, 08:24:43 PM »
I did a little of both for the intake. The PO had already put the engine and subframe in but that was it. The bulkhead had sort of already been cut back - some. Not enough though once I started looking at the intake. I got a guy to cut and weld it (its cast, so I didn't attempt something like that) at a tighter radius, so it fits great now. At the time when I was doing this, the silicone hoses were collapsing under vacuum, I think they got all that fixed now.

For the tow bar setup, if you look at the picture of the mini on the road in the turn and zoom in, you can see the placement of the brackets to the right and left of the red license plate. I did not cut the valence.

I can send you a couple pictures of the intake area if that helps. Not great pictures, just a couple of the area when I was taking it apart.

Offline jedduh01

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #22 on: January 23, 2017, 09:20:07 AM »
Ill add some memory of some details for adding the Towbar brackets I assisted in installation.

Mr Howe was OK with them being visible on installation.

First we used 1/4 steel Bar plate and made flat pieces drilled holes that matched the HF bar brackets.   
    The Actual HF brackets are Bolted to the 1/4 Plates.
The 1/4 Plates are welded to the Sub frame along the top.  And I also remember cutting triangle Gussets behind the plate for some strength to the frame behind just the top weld.

The HF Brackets Can still be taken off the frame and the remaining brackets sit flush with the valence. 
    An optional cover could easily be added to cover these up if wanted. and not be very intrusive.
 

Offline Bahowe1

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #23 on: January 24, 2017, 01:30:23 PM »
I owe some pictures...
@MiniDave - two pictures.  Neither great and both were during tear down.  One shows the cut bulkhead area, the other shows where the intake manifold fits in that space.  You can sort of see the welds there too.

On the tow bar brackets.  I will try to get you some better pictures.  I took some, but looking at them, I can't even tell what I am looking at.  So I will try again.

Offline Bahowe1

Re: '70 Mini - Rust repairs to Daily Driver (hopefully)
« Reply #24 on: January 24, 2017, 01:47:48 PM »
Alright, got some more done last Saturday.  Cut out some more in the rear subframe and rear half floor area.  Used my subframe to position and tack in my subframe repair piece.  Then cut and welded in the closing piece that fits sort of around the subframe repair piece and closes the fender area.  Then cut and welded in the floor.  I spent some time grinding, but have some more to do. 
I still have a question.  I asked this before, but it baffles me.  The last picture is a close up of the rear subframe mount piece and the closing panel that sort of reaches out to the side quarter panel.  There is a gap between that piece and the quarter panel, meaning water could sort of splash forward from the wheel and penetrate the rear bin area.  I am just holding the outer sill plate up, so you can see there is still a gap.  That is right?  If so... no wonder these things rust out!  I might have to figure out a way to close that up.