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Rust Spots Under Car, Should I Be Concerned?

JamesK

By JamesK,
in Exterior & Interior Styling

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JamesK Experienced

JamesK

Posted
Posted

I bought a R33 not too long ago, I had it checked by a mechanic and he said it was in pretty good nick however after giving it a wash the other day I noticed lots of tiny spot marks just behind the rear bumper and just above the exhaust muffler, Although it looks like that is expected (above the muffler) since there appears to be a metal cover over it which seems easy to replace. Not so sure about behind the bumper which is the housing for the spare wheel. Another concern is a bend I found in between the front and the middle of the car I'm not sure what the part is called but it's one of the two beams that run underneath the car from one end to the other (Refer to picture), I plan on sanding it back and painting it over the avoid furtur rusting however I wanted to know if you guys though the bend could lead to serious problems in the future.

Also does anyone know what that is they spray under the car? And if so why don't they spray it all the way to the end of the car?

Thanks in advance

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GTR-N1 Grand Master

GTR-N1

Posted
Posted

Hiya JK

Good News? I don't think that the rust spots are deep-seated... YET!

So-So News? I think that the rear end has sustained a slight shunt; but you can check the wheel well and investigate some more.

The different paint seems deliberate rather than overspray; but I don't think it was done very well.

Suss News? Looks as if the car and thus the rails fell onto a jack WTF. Weakened a little eh? Rust there is still only surface rust but I'd check the alignment of the car ie. the chassis rails are of equal length. And ask one of your mates to follow your car to see if your car is crabbing at all (ie running skewed).

I'm NOT a panelbeater; so what would I know? Just an observer. I'll read other following posts with interest.

Tez

some_cs_student Veteran

some_cs_student

Posted
Posted

That looks like very minor surface rust (I think, not an expert).

I've used rust converter but that's for serious rust issues.

You can use some anti-rust "etch" (?) primer, either way you can get any rust primers before you paint it again.

As long as you make an effort to remove the excess rust and re-paint you should be fine.

Look for articles on "surface rust" on this forum or others.

JamesK Experienced

JamesK

Posted
  • Author
Posted
Hiya JK

Good News? I don't think that the rust spots are deep-seated... YET!

So-So News? I think that the rear end has sustained a slight shunt; but you can check the wheel well and investigate some more.

The different paint seems deliberate rather than overspray; but I don't think it was done very well.

Suss News? Looks as if the car and thus the rails fell onto a jack WTF. Weakened a little eh? Rust there is still only surface rust but I'd check the alignment of the car ie. the chassis rails are of equal length. And ask one of your mates to follow your car to see if your car is crabbing at all (ie running skewed).

I'm NOT a panelbeater; so what would I know? Just an observer. I'll read other following posts with interest.

Tez

You got a pretty good eye there terry, thats exactly what happened the seller told me that the back was hit, although I'm pretty sure even he didn't know the damage was this bad (he was the importer) I paid 9.5 flat for it he didn't charge for rego or anything so I'm not to dissapointed but I want to make sure I can take care of my baby but I'll make sure I'll do what you said, Thanks for your input Terry

That looks like very minor surface rust (I think, not an expert).

I've used rust converter but that's for serious rust issues.

You can use some anti-rust "etch" (?) primer, either way you can get any rust primers before you paint it again.

As long as you make an effort to remove the excess rust and re-paint you should be fine.

Look for articles on "surface rust" on this forum or others.

i think u should use some under body protection spray like stone gaurd tis should help slow down the rust process ask ur local auto shop

Will do guys, on my way to my favorite autobahn haha

JamesK Experienced

JamesK

Posted
  • Author
Posted

Ok I always thought the car started to feel a weird vibe at 50-70kph I know this is a bit of a weird question but to someone with my car, do you think you could give it a small test drive?

Just to feel if everything is A1?

JamesK Experienced

JamesK

Posted
  • Author
Posted
THats not good buddy!

Looks like its only surface rust so thats good.. well not good but u get me

Yea I think it looks worse then it is and like you said it's surface rust I'll tackle it within the next few weeks

GTR-N1 Grand Master

GTR-N1

Posted
Posted
Ok I always thought the car started to feel a weird vibe at 50-70kph I know this is a bit of a weird question but to someone with my car, do you think you could give it a small test drive?

Just to feel if everything is A1?

Yes, like I said JK; get one of your mates to follow your car whilst it's doing variable speeds. Especially that 50-70Km/Hr range.

Crabbing?

That previous shunt could also have weakened the tailshaft so that a vibration occurs at a certain constant speed (rather than accelerating or decelerating). But up on the hoist, a mechanic could tell from pushing up on the joint.

Tez

JamesK Experienced

JamesK

Posted
  • Author
Posted
Yes, like I said JK; get one of your mates to follow your car whilst it's doing variable speeds. Especially that 50-70Km/Hr range.

Crabbing?

That previous shunt could also have weakened the tailshaft so that a vibration occurs at a certain constant speed (rather than accelerating or decelerating). But up on the hoist, a mechanic could tell from pushing up on the joint.

Tez

I'm quite worried now hahah if it is crapping and the tailshaft has been weakened how much do you guesstimate it will cost to fix? I'm quite concerned now because the trunk lid doesn't sit flush I always though it was cause that part has been pushed in a little but this makes sense that the bend pulled the whole car in a little and that would explain why it doesn't sit right....This really is starting to stink I prob better take it to Nissan....sigh* I guess this is what I get for buying so cheap

GTR-N1 Grand Master

GTR-N1

Posted
Posted
I'm quite worried now hahah if it is crapping and the tailshaft has been weakened how much do you guesstimate it will cost to fix? I'm quite concerned now because the trunk lid doesn't sit flush I always though it was cause that part has been pushed in a little but this makes sense that the bend pulled the whole car in a little and that would explain why it doesn't sit right....This really is starting to stink I prob better take it to Nissan....sigh* I guess this is what I get for buying so cheap

I really wouldn't worry too much at all JK.

Just do your checks and go from there. We only worry when the emotions/imagination races ahead of the logic. When I had my R33 GTR, I realised that a rear shunt had caused my tailshaft to go a bit weak. The car would vibrate at a certain range of constant speeds & I was told that it was the tailshaft. I was able to source one and it only took half an hour to change it - easy. No more vibration.

And fortunately, the rust spots are only surface atm (ie not bubbly). When you have the underside (and even the wheel well painted again), try and match it up so that you don't feel self-conscious when it comes around to selling the car one day.

And just do that follow-the-car check.

In the end, it'll be worth the trouble I'm, sure.

Cheers,

Tez :O

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