MGB exhausting

After cobbling together a quieter exhaust to reduce attention at the DEQ, today's post covers the effort to remove the pop-pop-pop from the exhaust that could also attract attention. So, more on the MGB exhaust...

Leak Finding
Again, remember that I hadn't made it through DEQ yet when I did this. With the muffler replaced, I shifted back to concerns which might interest the DEQ: the backfire. To find the exhaust leak, I simply started the engine with the hood up in my garage and listened. Nothing interesting... so I started feathering the throttle cable at the carb. With just a little rev, it was clear that the leak was coming from where the exhaust manifold meets the head closest to the firewall (#4).

Free Your Head
This is a pretty easy fix, even with the weird head on the MGB. I got a replacement gasket from NAPA, with a tube of the copper exhaust gasket sealant. After removing the gasket from the cardboard, I set the cardboard down next to it so I could align the fasteners to the relative position from where they came. This was so I could track which ones came from where when it came time to put everything back together again. I started with the nuts which held the intake manifold on. One at a time, I would remove the nut and washer, and then set them down relative to where they belonged on the cardboard. Once the nuts holding the intake were off, I slid the intake off the studs, put a latex/rubber glove over each intake to keep foreign debris out and then gently set the intake against the inner wheel well.

With the intake off, I shifted to the exhaust nuts, following the same pattern of one-at-a-a-time and setting it in its relative location. Once the nuts and washers were off, the exhaust manifold slid off and it could be lowered out of the way. Now, the old manifold gasket was exposed.

Scrape Your Face
Most of the old gasket came off in one piece, but some bits held on, and needed to be scraped off. Once the main gasket was off, I took a razor blade and scraped the entire area clean. I followed that with 150-grit sandpaper to make sure the head surface was completely clean. I checked the manifolds for residue, but scraped and sanded to be absolutely sure I had clean, flat surfaces. With the surfaces on both the head and the manifolds shiny clean we were ready for reassembly.

Copper Permatex
There are so many kinds of sealants and gasket makers on the market, going simply by color can be a dangerous thing. When it comes to Permatex, the genuine article, the colors match what you think they would be. Still, read the package before you use any. For helping the exhaust and intake manifolds on a MGB to mate to the head, you want to use the copper. It has thermal qualities which assist in keeping the temperature between the head and manifolds consistent while holding the seal at very high temperatures. I put a thin bead on both the head-side and the manifold side, not knowing which side needed is more. Following the instructions, I attached the manifolds finger-tight, waited an hour and then torqued them down.

Testing
The following day, the car was ready for another test drive. This time, I took T with me and we laughed as we tore around the neighborhood. The brakes felt good, the gears shifted tight. Most importantly, the exhaust wasn't popping incessantly and the overall din wasn't too bad... under 30mph. The next day, T took the car out, picked up his brother and ran it through DEQ. I posted on that earlier.

Next
Since the car made it through DEQ, I can focus resources on a good exhaust versus the strung-together with bailing wire and soup-cans exhaust that's in there now. I looked high and low for a Peco, but they aren't manufactured any longer. The few that are on the market are the leftover stock, and they are priced accordingly. I considered the Tourist Trophy, but the sound samples I've heard didn't grab me like the Peco did. Part of that could have been the tinny-ness of the stainless steel, but I have heard that as the stainless ages, the tinny-ness fades away. Then, I learned from the fine folks at EnglishParts.com that the stainless steel Bell systems are built with the same design (and tooling) as the mild-steel Peco ones were. So, given time, the stainless Bell system would age into a sound just like the Peco... in theory. Food for thought.

That's it for today. Thanks, as always, for following along-

MGB muffled

Continuing the saga of getting the MG summer-weather ready, today's post covers some fun with the exhaust system. I started this post a few months ago and forgot about it, so recognize this was before I got through DEQ. So, I was doing things that were lowest possible cost in case I needed money to get through DEQ (think engine rebuild, etc).

Quiet You

In each of the test drives where I verified my fixes, I couldn't help but notice 2 things. First, the MG was loud as #$%!. Second was the unmistakable sound of an exhaust leak (pop pop pop). Out of curiosity, I pulled out a decibel tester app on my phone and checked. Parked in the garage with the doors open, sitting in the driver seat, I started the engine, and pushed the revs up to 3k and back down. I peaked at just shy of 100dB. According to the application, that's as loud as a blender. In the driver seat.

When we had the donorZed, I noticed that the exhaust was the same smaller-diameter piping as the MG had: 2". In the interests of getting every usable part off that thing, I cut off the rear muffler (which was surprisingly not that rusty), and the catalytic converter (cat). I figured that one of the two cars could use one or both of those parts, and with DEQ smog a part of ownership of these cars for the foreseeable future, one of them would eventually have use for the cat.

So, with the blender-loud exhaust reality in my face, I decided to start with the muffler going onto the MG. One would reasonably think that the crazy-bending exhaust plus muffler wouldn't "just fit". And, it sort of did.

Soup Can Exhaust

Most of the exhaust system on the MGB is coated with rust. The pipes, the little cherry-bomb mufflers, even the exhaust manifold. There is deep rust everywhere. This makes welding replacements all the more difficult because you have to get to clean steel to have a good strong weld. Fortunately, there are no-weld joiners available for most standard diameter sizes. These are somewhat simple in their design with a straight section of pipe with an integrated band clamp at each end. You put 2 cut ends of pipe into each end of this thing and tighten. Simple. It reminds me of the old-skool way to patching a hole in the exhaust: cut a soup can into a patch and get it to hold on with hose clamps.

All of this leads us to my noise reduction. The MGB had 2 cherry bomb mufflers in sequence which were not really muffling noise at all. So, I cut off the one on the back and fitted the one from the donorZed. With some careful cutting, I was able to get the 2 straight sections to abut, but there is not an off-the-shelf no-weld joining thing to connect them. So, I went back to the old-skool roots and cut up a small can, and hose-clamped it together. Yeah, I'm not that proud of that, but remember, this was done before I got through DEQ.

I re-used the hangers that were there from the cherry-bomb muffler, and it was ready for testing. Total cost: $0. I tested the noise level the same way: car in with the garage doors open. dB levels hovered in the low 90's, so I shaved up to 10% of the noise just by putting a bigger muffler on. Truth-be-told, the muffler from the donorZed looks an awful lot like the stock MGB muffler. During the test-drive, it became clear that the rubber had completely dried up, so I had to resort to holding the center section of pipe off the ground with bailing wire. Yeah.. not too proud of that either.

I'll get after the backfire in another post. For now, the exhaust is quieter, if not in a better long-term disposition. My thinking: don't attract unwanted attention by the tester at DEQ. That includes disconnected things under the bonnet and a super-loud exhaust which might imply something non-stock is going on.

Anyway, that's it for today. I'll post on my attempts to solve the backfire and other developments as I do. Thanks, as always, for following along-

Bus starter replaced

Brief post today about replacing the starter in the TDI-powered microbus.

Beginning by Not Starting

After getting the radiator replaced, I was unable to take a test drive because I couldn't get Hapy started. I assumed it was the annual ignition wiring issues, but I was wrong. The great unwiring I did two years ago (See Another Tow) actually worked two years later. The true issue was the starter finally failed. The starter that I was using was a gift from Justin. He had a customer who was complaining about noises coming from their starter, even though it worked fine. It kind of ran-on a couple of seconds after releasing the key post-start. While this is an indication of impending failure, it was working fine. Justin replaced it, and offered me the starter for the project microbus. It being free, I obviously accepted it, knowing that the day would come when the starter would become inconsistent and then just not work. Well... the becoming inconsistent didn't happen; it just failed.

Start Out
Removing a starter is not complicated, but I'll cover it anyway. Disconnect the battery cables from the battery first. This should be obvious, but so often we get excited about the job, and forget. Next, unplug the trigger wire that comes from the ignition and plugs into the solenoid with a small black square clip. Pinch-and-pull. Next, remove the bundle of wires which are ring-terminal'd onto the back of the starter. This should be a 10mm nut. With the electrical out of the way, grab the (IIRC) 19mm socket and remove the top bolt. This bolt is longer than the other, and you go after this one first on the bus because it is the one that is harder to get to (you're on your back facing up). Then, remove the lower, smaller bolt from the bottom, keeping a hand on the starter as it loosens. It is heavy, especially lying down underneath, so brace against it falling on your face.

Start In
I took the old starter over to Discount Import Parts (now only on the east-side - don't get me started) and got a rebuilt Bosch from them. Since I had the old starter in hand, I didn't have to pay a core nor drive all the way over there a second time. The install is literally the reverse of the removal: wrestle the starter up into position (solenoid above the starter) and rotate it left and right while pressing the smaller bolt into the lower hole. Once it catches, thread it in with your fingers until it is holding. Then, finger-in the top longer bolt. Once they are both finger tight, tighten with the sockets. Wire up the ring-terminal wires with the 13mm, then plug in the trigger wire.

Once the starter was in, Hapy fired right up. His test drive was pretty great. A charged-air pipe separated from one of the rubber connectors again, so I'll need to solve for keeping that together. Otherwise, I drove to the gas station and filled up with B20. Last tank of fuel: 39mpg. When compared to the 16-19 mpg I was getting with the gasoline engine, 39 is absolutely astounding. I rewarded Hapy with an oil change.

That's it for today. Thanks, as always, for following along-