Loud Noises! and Gear Oil (Chevelle Update)

"MM54" (mm54mk2) 04/24/2016 at 18:47 • Filed to: '71Chevelle

1

6

Due to a sequence of happenings, work time on the Chevelle yesterday was limited, but it was still a worthwhile 250-mile round trip to work on it. And I have a video this time!

But first, the quiet stuff. I remembered to take the little oil pump this time, so I was able to change the oil from the diff.

Mmm, smell that gear oil

It’s in better shape than I expected, certainly better than the one in my P71 (which admittedly has almost twice the mileage). The oil wasn’t too awful either, which makes me think this may have actually been changed before, I’ll have to look through the old records some time to see if that’s the case.

I spent a considerable time staring at the stamping on both the ring gear and pinion trying to figure out why it says “LOW” before turning my head and realizing it was upside down, and actually says “M47" which is probably the code for this ratio, which I believe to be 3.08:1. Yes, it’s open. No, it won’t stay that way long-term.

Closed that back up with some black RTV and put in about 1.75qt of Lucas 80W-90, which should do well.

Next up, the old exhaust hanger, which wasn’t connected to anything other than the frame, came off. Well, not really “next up” since my dad volunteered to help while I was doing the diff oil, so it came off around the same time I put the cover back on the axle.

Tetanus

The pipe had rusted off from that on both sides, leaving the tail pipe on the ground and the rest of the system swaying in the breeze. Thanks to the unbelievable undercoating from the previous/original owner, though, the bolt came out without issue (no penetrating oil required!).

The next logical step was then taken.

Note how the lowest part shown (the tailpipe) rusted all along the weld.

With that out of the way, we (my dad and I) proceeded to take scrapers and wire brushes to the frame, in particular this day was the rear rails and the crossmember in front of the axle, since those are most obscured by the exhaust system.

I don’t know what sort of undercoating this is/was, but, where it hadn’t dried and started to peel within the last few years, it was very strongly holding the frame. There is the same stuff on the floor boards - scraping it off reveals original black paint on the bottom of the car. Same deal on the frame - underneath it’s mostly clean metal, paint, or a bit of surface rust.

I replaced the gas tank in 2012 since the original leaked pretty badly above 2/3 full

Unbolted the brake line clip since I’ll be replacing that line later - also allows me to get POR15 behind it.

So thank you, previous/original owner, for putting this rubbery greasy undercoating on everything, it did so well underneath that I’m not even upset that almost the whole engine bay is covered it in, too.

Removing this was a lot of work, and filled the mini shop-vac when cleaning up. Once it was clear and wiped down with some mineral spirits, a healthy coating of POR15 was applied, which, despite my best efforts, made its way onto my arms, so I have some temporary tattoos now until that skin wears off.

Having completed this, the car was set back down on the ground, and naturally, since the exhaust now ended at the Y-pipe under the passenger’s seat, started up.

In typical Go-Pro video fashion, you have no idea how loud it was (unless you’ve heard a smallblock with open exhaust in person before, then I guess you do) but it sounded so very good. It’s also running so rich that I had to stop because I couldn’t see with the exhaust burning my eyes. Probably should have opened the rear wall (that whole wall behind the car is held with 5 bolts and can easily be removed to get the car in/out).

So what’s next?

This coming weekend there’s a swap meet in Canfield I’m going to try to get to so I can hopefully pick up a set of wheels. That will occupy enough of the day that I’m just going to try to hang out with some friends afterwards and not expect to get anything done on the car until the next week.

That next week, I’d like to get more of the frame/floorboards scraped and POR15'ed, in addition to starting the inevitably-arduous process of getting the manifolds off the engine after spending 45 years rusting the bolts to everything. I’ve sprayed them weekly with Kroil so we’ll see how it goes.

Urambo Tauro > MM54 04/24/2016 at 19:01

2

That battery didn’t sound very enthusiastic...

My bird IS the word > MM54 04/24/2016 at 19:10

1

You looking at exhaust systems? I’m planning on a pypes cross flow system this summer. The race pro mufflers sound mean(and not too loud). Glasspacks sound good on everything, but they don't always sound as good as a system built for the car.

MM54 > Urambo Tauro 04/24/2016 at 20:09

1

Yeah the one in the car is shot (it can restart it if it stalls, but let it sit a day and it’s flat), and that other group 65 (from my old crown vic) we’ve been jumping it off of is getting pretty low (though it’s good, usually lives on a trickle charger). I’ll be picking up a fresh group 78 for it... eventually. It’s got another couple months’ work ahead of it before I put it back on the road, so no rush yet - just would be wasting part of the warranty.

MM54 > My bird IS the word 04/24/2016 at 20:12

1

I have a 2.5" stainless system with Pypes Race Pros sitting in my living room at the moment - though I’m going with an h-pipe rather than an X for both sound, packaging, and cost reasons. I just need to pick up some stuff so I can make pipes from the shorty headers (no desire for long tubes on a daily that’s already only 3" off the ground...) back to where the collectors would normally be. Hoping to have it buttoned up mid-May so I can get cracking on the brakes and top-end work.

My bird IS the word > MM54 04/24/2016 at 22:03

1

Think all you need are the collectors and maybe an extension. going for a full dual x pipe on mine.

MM54 > My bird IS the word 04/25/2016 at 17:44

1

I’m thinking I’ll be able to get away with a 45 on each side off the collector and then an extension straight back; no way to know really until I get the manifolds off and the rest of the system mocked up though.