After getting the fuel tank and line unplugged and somewhat cleaned out, I dealt with the carburetor – a Stromberg. My 64 had dual SU’s, which were a real challenge to deal back in the 70′s when I had NO special tools. This was my first time wrestling with a Stromberg. But now there is lots of cool info on the internet, lots of cool tools (wow, look the Gunson Colortune where you can LOOK at the color of the flame through a clear spark plug, and adjust till blue. AWESOME: http://www.youtube.com/watch?v=6hFUvQ4gaPcat ) I looked at prices for a rebuilt. Saw prices around $275 www.paltech1.com/id2.html. A replacement downdraft Weber was $295 on EBay. I bought one, but it looked awful and I didn’t like the bonnet clearance, or the fact that it wasn’t legal in CA, and didn’t like the price of the side draft. So I sent it back, and decided to try low budget just to get it running if I could with minimal investment.
To just try to get it good enough to start, I prepared by reading/watching:
- the Fuel, Carburation, and Emissions section in Haynes
- the links here: http://www.triumphspitfire.com/carbs.html.
- Great overhaul and symptom docs: http://www.scribd.com/doc/7821863/Stromberg (this helped me solve an air bypass problem later).
- Adjustment Strategy and Tools: www.vtr.org/maintain/carbs.shtml
- University Motors Youtube 3 part video of a Stromberg rebuild:
I tried to identify which Stromberg specifically it was – with no luck. Remember this is a later 1500 engine of unknown year, and much of the emissions stuff was not transferred over by the guys I bought the car from. My goal here was to just to get it running, not rebuilt or tuned yet. I did the following things (which proved to be successful later to get it started), without removing the carburetor from the manifold.
Minimal Steps to Just Get it Running:
- Cleaned the outside: simply sprayed it down with carb cleaner.
- Cleaned the Float Chamber: removed the cover, sprayed it with carb cleaner. It was ok inside, gas was stale but not gummed up, floats ok, needle valve a little sticky, but worked it and sprayed cleaner on it, freed it up.
- Cleaned the Air Valve Piston: it already moved freely. But I removed the dashpot cover, and the piston – it was dry, no oil. The diaphram looked good. The needle was slightly corroded. Sprayed carefully with carb cleaner/wiping with paper towel, avoiding the diaphram as possible per the many posts out there saying carb cleaner will damage it. On the needle tried using just a green scrubby, then resorted to a Dremel tool with the plastic (or whatever it is) polishing wheel (NOT the metal one). Put it all back together, made sure the screw in the piston was aligned out towards the air filter, as well as the node on the dashpot cover per the diagram here: http://www.triumphspitfire.com/images/carbs/zs1.jpg. Refilled dashpot with 30weight engine oil. Put way too much in it, spilled all over the place. OOPS.
- Examined the Temperature Compensator Unit: Removed, everything looked just fine. sprayed with carb cleaner, let dry, replaced.
- Freed up Choke Cable: Choke was frozen. Disconnected choke from carb, sprayed WD40 where the cable wire comes out of the cable sheathing. Got in the car, and worked the choke until it freed up. Reconnected the choke, adjusted it so that it shut all the way.
- Cleaned up Choke: Removed manual choke unit from the side of the carb, sprayed with carb cleaner, used toothbrush to work into each progressively large hole. You’ll see, there are progressively larger holes that align to each click of the choke knob as you pull it out. Replaced everything.
What I did NOT do:
- Mess with idle adjustment screw
- Mess with the air bypass mechanism
- Rebuild it
- Buy the cool Gunson tool (will do this later, just for fun!!!)
As we will find out later, this was sufficient to get it running… Whew! For the cost of a can of carb cleaner….