89 Civic Sedan | Rear Subframe Issues

[dozey]

Good afternoon gentlemen,


Per the title, I have some serious issues with the rear lower subframe (brace) on a 88 Civic Sedan. With this particular model, the entire subframe and brace assembly is spot welded to the chassis a little way infront of the spare tire well (there's no sway bar either).

The problem is, the left half of my assembly has suffered some degree of torsional distortion and two tears have developed. The first tear is located at the left hand observation (presumably?) hole on the subframe brace (there's one on either side); torsional force has caused it to twist slightly and tear a 2cm crack from this hole that continues a little way around the corner of the brace. In addition to this, another small tear or split has formed where the subframe assembly is spot welded to the chassis above the lower control arm attachment points.

Since the entire subframe assembly seems to be spot welded to the chassis, I'm contemplating welding length of C section (U shaped) mild steel over the majority of the subframe brace and then adding a few additional brackets fixing it to the chassis above (avoiding point loads etc).

I'm not entirely sure of this solution and another potential fix that comes to mind is just grinding off the entire subframe assembly and using a later model bolt on subframe (with inherent reinforcement of the chassis bolt points).

Your thoughts, suggestions or experiences would be much appreciated!


I'll try to follow up with some pictures in the next day or two.


Here's a picture of the assembly (lifted from another forum, this one is deformed much worse than mine). I've marked the location of tears / cracks in red and proposed application of steel reinforcing in white (the actual steel has a U shaped profile and would slot right over the rear brace).

http://i.imgur.com/j11XZ.jpg

[Bludger]

Your thoughts, suggestions or experiences would be much appreciated!

Unless you can grind off and weld a new one in by yourself. I mean you're able to do it cheaply, get friends to help or whatever.

Anything but having to pay a professional to do it for oyu.

I would just get another car.



what modifications have you made or what do you use your car for?

these things don't just happen from the everyday commute.




I've never heard of weld on subframe braces.

[dozey]

Unless you can grind off and weld a new one in by yourself. I mean you're able to do it cheaply, get friends to help or whatever.

Anything but having to pay a professional to do it for oyu.

I would just get another car.



what modifications have you made or what do you use your car for?

these things don't just happen from the everyday commute.




I've never heard of weld on subframe braces.

New car / body is definitely the smart solution. However in this case I'm definitely looking for a fix.

Like you said, it certainly wasn't an every day commute; she limped out of some very rugged terrain in northern NSW with a huge tear in the sump a year ago, but this little treat only revealed itself when I peeled back the rubber coating on the subframe and chassis a few days ago. The car is basically stock, but I'd like to keep it going for sentimental reasons if nothing more. The dual carb D15s seem to be a bit of a rarity too (functional dual carbs anyway).

I was sort of hoping someone might have done a cut and replace with a later model bolt on subframe for the added sway bar. Failing that, even a modicum of assurance that the chassis will actually support added reinforcement would do a lot ease my mind.

[Bludger]

get some pictures and we'll go from there.

[hondapop]

Don't let sentimentality get in the way of sensibility. Any damage to this section that is affecting the alignment and safety of the vehicle will require a new blueslip in NSW I'm pretty certain, and any welding/bracing would have to passed (and probably certified), so weigh up the costs and consequences very carefully before spending heaps on a car that sounds pretty battered.

[dozey]

Don't let sentimentality get in the way of sensibility. Any damage to this section that is affecting the alignment and safety of the vehicle will require a new blueslip in NSW I'm pretty certain, and any welding/bracing would have to passed (and probably certified), so weigh up the costs and consequences very carefully before spending heaps on a car that sounds pretty battered.

Agreed, I'm definitely weighing up the financial and reliability aspects before dedicating any significant resources to a fix.

[dozey]

get some pictures and we'll go from there.

Pictured below.

http://i.imgur.com/HP3fX.jpg (http://imgur.com/HP3fX)

http://i.imgur.com/e2GFx.jpg (http://imgur.com/e2GFx)

http://i.imgur.com/6oQjE.jpg (http://imgur.com/6oQjE)

[hondapop]

I'm a sheetmetalworker by trade and I have to admit that I should have been a panelbeater 'cause cars and car customising and mods is where my interests have always been.

In the past I have taken on repairs like this (because I could and thought it was fun, and I still do to a lesser extent), BUT if I'd had any sense, I wouldn't have 'cause my time and effort would have been better spent.
To get this repaired professionally is gonna cost.

My thoughts are (not advise) are that it's more trouble than it's worth.

[pat88c]

Two smart men said before Not worth repairing
Best find another ED civc and swap over all of the good bit from your into new civic, Sell as parts or scrap metal the car

Pat

[Bludger]

After seeing your pictures I would......

- Clean up the whole lot.
- spot weld it up.
- weld on additional support braces.

After all this, I would say you'll be alright.
I wouldn't let anyone know, because you will have issues getting a rwc.
But in all honesty, after bracing it up, I would say you'll be right.

This is what I would do.

srs'ly.

[Bludger]

Going by the pictures in the 1st post, it looks very deformed and would definitely need to be changed.

The actual photo's of your car still looks pretty straight.

So yeah, welded up and braced..... is alright i reckon.

Like I said, that's what i would do.

[mocchi]

yea bracing would be ok i guess with some 2mm+ sheet metal.
to remove rear subframe theres abt 30+ spot welds you gotta drill, really hard work.
havent done it before but got info from eg chassis repair manual, just assuming its the same with 89 civics.

[dozey]

Thought I'd follow up on this, but unfortunately no repair pictures yet.

I did try convincing the vehicle's owner to just scrap the chassis for something safer and cheaper, but at this point I think it's going to take a catastrophic engine failure before that happens.

We were able to cut, form and weld a section of angle iron to follow the contour of the subframe and essentially reinforce the entire brace. The cracks and tears further up above the lower control arm were a bit more challenging and I ended up cutting, lapping and welding a small plate into the indentation around the damaged areas.

The car has probably done over 2000km since the repair and both the alignment and structural integrity seem fine. It's safer than it was before and that's definitely a result I'm happy with.

There are no more repairs in this car's future... but if she can go the distance between 350,000 and 500,000 on her own I'll be shedding a secret tear.


Thanks for all the helpful advice!