I finished removing the SU carburetors from the car. It was difficult to get to some of the nuts that hold the carbs to the intake manifold, particularly the lower ones, and this job took me about ninety minutes to complete.
This is how the carbs looked before I started. The first thing I did was to remove the choke cables that connect to each of the two carbs, one on each side.
There are fuel hoses that connect across the tops of the carbs as well as two hoses at the bottom. I disconnected all of these next.
There is also a smaller hose that connects to the front carb only and then runs over and terminates by the distributor. This hose is for the distributor’s vacuum advance.
There are four nuts that hold each carb to studs on the intake manifold. I used a 13mm box-end wrench to loosen the top nuts first. There is a heater hose that feeds the heater core inside the car–I found that by removing this hose connection I gained some area to maneuver towards the two lower nuts.
A 13mm wratcheting wrench was also helpful in getting these loose on the front carb first. Then I removed the front carb entirely in order to gain better access to the lower nuts on the rear carb.
It was tricky to reach those lower nuts on the rear carb, but I was able to get them off by standing in front of the car and using a box-wrench and wratcheting wrench once the nuts were loose. Once those nut were off the rear carb came right off the manifold.
Here’s a shot of the engine bay following my most recent work.
I ordered the “Just SUs” video from zTherapy last week and hopefully it will arrive during the upcoming week. Once I’ve had an opportunity to review the video I’m hoping to be in a position to dig into the carbs and see what, if anything, needs to be replaced or rebuilt. In any case I will be giving them a thorough cleaning.
This morning I removed the coolant overflow tank, which is mounted at the front of the car on the driver’s side.
One of the bolts that secures the radiator feeds through the upper bracket on the overflow tank, securing the overflow tank in place. Also, there are two philips head screws that bolt the tank into the body at the bottom.
Remove those two screws and the tank comes out. I will clean iut up, wash it out, and maybe give it a fresh coat of black paint, if it needs it.
This afternoon I finish-painted the gas tank. I used a Rustoleum Industrial enamel spray paint, which is the corresponding finish paint to the primer I used on the tank. The color I chose was “Semi-Gloss Black” so the tank will have a nice sheen.
I also took the opportunity to put a coat of black paint on the fan shroud.
And I put a new coat of paint on the the air cleaner assembly. No need to prime those pieces first because the old paint was in fairly good shape. I used the same type of spray paint I used on the gas tank, only I chose a color called “Safety Red.” At the store there were several shades of red available and this one seemed to match the existing paint the best. Here is a picture of how they turned out when done, as well as another picture (right) that shows one painted and one unpainted side-by-side, so the colors can be compared to one another. The Safety Red is pretty close, but a bit brighter and less orange than the original.
When I take my radiator in to the shop to have it checked out I am also going to take in the car’s heater core. In order to get to it it is necessary to take apart the heater. The heater is basically a box that goes up under the dashboard in front of the radio. It is bolted into the car from outside the vehicle; the bolts come through the engine bay. The unit itself contains the heater core and fan assembly. The box is in two parts. Eight small screws and a few taps with the mallet separate the two pieces of the heater box.
The larger section (pictured left above) contains the fan unit, which is attached with three screws into the box. Remove those screws, a bit of prying, and out comes the fan.
Here is what the fan looks like removed. There are two electrical connections for the fan motor.
Back at the box, you can now see where the heater core sits directly in front of the fan. I used my hand to push down through the recess where the fan goes to start to push the heater core out of the box. It comes out with a bit of coaxing.
The core looks just like a little radiator, and basically that’s what it is.
I plan to flush the core with the hose and otherwise clean it up similar to the radiator before taking them both to the shop.
While I’m waiting to get the heater core back I’ll clean and paint the heater box so it looks nice.
This morning I spent some time cleaning the parts I removed from the car during the week. First I cleaned up the air-cleaner assembly. I used some Spontex scouring pads I bought at Home Depot (8 6″x9″ pads for $2.64) and some hot water and Simple Green. This combination works pretty well at removing all of the grime and grease.
Following that I spent some time cleaning the fan shroud and radiator. They came pretty clean as well.
It rained this morning but the humidity is supposed to come down in the afternoon, so I hope to get some painting done a bit later.
I’ve been doing some research into the options for re-building my carburetors. I’ve gathered information from members of the 311s.org forums and from searching the archives of the Roadster mailing list, both excellent resources full of knowledgeable people willing to share their experiences.
My personal preference is to re-build them myself, but my #1 priority is that they function correctly and for that reason I believe there may be some portions of the job better left to the professionals.
I have found three vendors that will re-build carbs:
- zTherapy, Inc., located in Salem, Oregon, sells re-building kits ($150) and parts, offers full re-manufacturing service ($595), and offers throttle-shaft re-building service ($175).
- Keith Williams in Las Vegas, a mailing-list member that has already helped me out by recommending which parts I’d most likely need to re-build the carbs myself, re-builds carbs on the side. I have heard nothing but good things about how nice Keith’s carbs look and function.
- Apple Hydraulics, located in upstate New York, offers services to people restoring cars including full-service SU carb re-builds ($395) as well as re-building just the throttle shafts ($150).
Additionally many of the roadster parts vendors stock parts for the re-build, and some of the parts are still available from Nissan.
My first step is to order from zTherapy their “Just SUs” video ($20), which is renowned as the best resource for learning how the SUs work and how to tune them yourself. I’m hoping that video will give me the knowledge and/or confidence to determine what I can handle doing myself and what is better left to the pros.
I got a recommendation for a good radiator shop here in town from John Shea at Japanese Motorsports in Round Rock. John has been working on Datsuns and Nissans for something like 20 years and is a great mechanic and resource. John recommended a place called Radiator King that has been in business for 19 years and has a good reputation for quality work.
I’ll be taking my radiator and heater core in right after I clean them up a bit.
Today the humidity was low so I got a chance to prime my gas tank. I used a Rustoleum grey enamel spray-primer designed for industrial applications. It was a bit windy today, which presented a problem, but overall I got good coverage on the tank. The sun heats up that tank quickly, and the paint dried fast.
This morning I removed the radiator. It took some creative maneuvering, but the radiator cooperated in the end. There is a sort-of circular bracket attached to the radiator that floats between the rad and the fan, which comes off first. I had to rotate it around 180 degrees in order to get it free.
Then there are a total of three hoses to be disconnected. The one on the bottom is the most difficult because it is the least accessible and the biggest. Then there are three horizontal and three vertical bolts that hold the radiator into some cross-pieces that attach to the body. Then the piece just lifts out.
I will have the radiator checked-out, re-cored if necessary, and then clean it up and paint it if necessary.
I then removed the air-filter assembly from the carbs. Two “torpedo” bolts hold on the outer cover, then out comes the filter itself. The inner cover is mounted to the carbs with four bolts, two of them have these long heads which make them easier to remove.
Tonight I removed the grill from the front of the car. Overall it is in decent condition, although there are a couple of dents and the chrome could be polished or re-done (similar to all of the chrome on the vehicle).
The grill just mounts to some cross-pieces that bridge the front of the body between the fenders, on some brackets.
After removing a trumpet-style aftermarket horn, I saw the OEM horns were still mounted on either side of the grill. I pulled them off and we’ll see if we can’t get them cleaned-up and working again.