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Topic: Rear Underbody Resto/Gas Tank Install (Read 10451 times) previous topic - next topic

Rear Underbody Resto/Gas Tank Install

Well ... the car has been out of commission for over a year now.  It wouldn't start one day and I eventually diagnosed a fuel pressure issue.  Pulled the tank to find the fuel hose inside of the tank had split and thus not allowing the system to build much/any pressure.  In classic "while I'm at it" fashion, I decided to take it further ...

Once I pulled the tank, I figured it was a good time to address some corrosion on the underside of the car.  A little history ... my parents bought the car brand new around Christmas of '84 and pretty much gave it to me when I graduated from high school in '97.  It needed some minor stuff at the time, but they gifted it to me versus trading it in on their next vehicle, and I worked on addressing the minor stuff it needed.  The "bad" thing in all of this was that we lived in northern lower Michigan at the time ... a place where winter can last months (from October to May one year while we lived there).  The car got driven in plenty of foul weather and was exposed to a lot of salty roads.  I tried to keep it clean and wash it, but there's only so much you can do when it's below freezing.  I undercoated it at least twice, but I knew I was just covering up some of the issue.

So ... with the tank out, I decided I would se and chisel off all of the undercoating (from the rear seats back) and wire wheel any rusty areas I came across to clean them up.  I then used the POR-15 three part process to address the rust and re-coat the underside of the car.  After all of the wire wheeling, I degreased the underside, rinsed it, then treated it with a metal prep solution that etches the metal and leaves a white residue in the diseased areas.  When that's all done, you rinse it all off again and let it dry.  These areas aren't horrible, but here's a little of what it looked like before I started the painting process:

Rear Underbody Resto/Gas Tank Install

Reply #1 –
Here's a few shots of the progress on the painting.  I would consider the POR-15 more of a coating then a paint.  You can brush it on, but I typically used a foam brush.  You can kind of just dab it on and it smooths out pretty nicely ... almost self leveling in a way.  I'm hoping to get a good portion completed this weekend.

Rear Underbody Resto/Gas Tank Install

Reply #2 –
That was pretty clean underneath for a Michigan car.

That looks like it's coming out really nicely so far.
It's Gumby's fault.

Rear Underbody Resto/Gas Tank Install

Reply #3 –
Quote from: Tbird232ci;468782
That was pretty clean underneath for a Michigan car.

That looks like it's coming out really nicely so far.

Thanks.  I spent a lot of time cleaning it up and there are worse areas than those on the trunk well.  Sucks, but hopefully I can get it addressed and then won't have to deal with it again.  Car doesn't see snow anymore and only sees water to get washed ... so I'm hoping this holds up for a long time to come.

Rear Underbody Resto/Gas Tank Install

Reply #4 –
Today's progress thus far ... made it over to the passenger's side ... pluggin' away.

Rear Underbody Resto/Gas Tank Install

Reply #5 –
that house shaped stamping into the trunk area,,

thats the part you cut out and convert it into a water tight hinged door.

this way in the future you simply open it up from inside the trunk to go in after your fuel pump next time it goes bad.  no more droping the tank

Re: Rear Underbody Resto/Gas Tank Install

Reply #6 –
Decided to go further and just take care of the whole back frame.  Getting close to wrapping up the paint piece and can hopefully start putting things back together.

Re: Rear Underbody Resto/Gas Tank Install

Reply #7 –
Wow! that is looking great.  I need to badly do that also. 
Mike

Re: Rear Underbody Resto/Gas Tank Install

Reply #8 –
Quote from: 85CougarCobra – on
Decided to go further and just take care of the whole back frame.  Getting close to wrapping up the paint piece and can hopefully start putting things back together.

Oooh shiny. I like it.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Re: Rear Underbody Resto/Gas Tank Install

Reply #9 –
Another "while I'm at it" moment ... taking this to get shortened up today.

Re: Rear Underbody Resto/Gas Tank Install

Reply #10 –
The bottom of the car looks great refinished. 

What did the aluminum drive shaft come out of?  Crown Vic?  year?
1988 Thunderbird TC, 5spd
Stinger 3" single exhaust, Cone Filter, Adjustable Cam Pulley, Schneider roller cam, Walbro 255 lph, AEM Wideband O2
'93 Mustang Cobra replica wheels on 235/50R17

'21 F150 Powerboost
'17 Husqvarna TX300

Re: Rear Underbody Resto/Gas Tank Install

Reply #11 –
Yep ... 2004 Crown Vic ... $40 at the junkyard.

Re: Rear Underbody Resto/Gas Tank Install

Reply #13 –
I'll keep you posted.  I don't expect the actual shortening piece to be too crazy expensive.  I'm getting a replacement yolk and pinion bracket though so that I don't have to run the adapter style u-joints.  That will probably be adding more cost than anything.

Re: Rear Underbody Resto/Gas Tank Install

Reply #14 –
Quote from: 85CougarCobra – on
  I'm getting a replacement yolk and pinion bracket though so that I don't have to run the adapter style u-joints.  That will probably be adding more cost than anything.

Is there a downside to the adapter U-joints?  Sounds cheaper, but I don't know anything about it.
Mike