Sorry for the delay on the Mikuni TM32 carb change over. Here is where I am at, now that I changed the needle valve jet to a 1.5 I was still experiencing the engine burning rich. So I order a couple of smaller pilot jets, as well as 4 smaller main jets. I now have the #40 pilot jet in, I have it tuned to 1 and 3/4's turns out on the air mixture screw and it idles perfect. FYI for you do it yourselfers, I use a piece of white "old" TEE shirt to perform a quicker check of how rich the engine is burning, it is not perfect but it gets you close. Take the white cloth and stretch it over the exhaust pipe and time it for 15 seconds, so every time you adjust your mixture screw and the such make comparisons. It should be very very light on the cloth, then when you think you have everything close drive it for awhile. Then pull a plug and check the plug for the burn. Now onto the Main jet, it comes from the factory with a #250 main jet, I am currently down to a #220, I may go down one more to the #210. I will see how the plugs look after a few days, but I still don't have the top end power yet. Also I have the needle currently clipped in the #2 position, I may move this as well to the #1 position for a little more air flow. Oh, one more thing. If your planning on doing this conversion be aware that this carb takes very little fuel pressure, I am learning this the hard way, now I am down to a 1.5 to 2.5 psi Facet pump. I had a 4.5 to 7.5 Facet on there before and it was way too much pressure.
For replacing carburetor, clean the area where you will mount the new carburetor. Scrape off all dirt and gasket material and, using a strong solvent, clean the area. You don't want the carburetor sucking air because of an imperfect seal. Place the new gasket in place. The gasket should have a light coating of gasket sealer on each side. metal identification tags
Its benn a while since I've been on and was checking to see any progress with any other carb swaps. I moved back from western Alaska to civilization and now have a garage to work in. Wonder casper if you ever got cables made and where after having numerous of my own cables failing. Hope its still running good.
I have a Mikuni BSR 36mm that may need to find a new home in the future... if anyone wants to buy it though, shoot me a PM.
I see this is a old thread but this is what I'm trying to do If anybody can answer my question please jump in. I am in need of the carburetor mounting flange that goes In-between the carb and the manifold. On my 3G83 Mitsu manifold I have a measurement of 80mm mounting holes from center to center than I need on the other side to be 40mm to affix a Kien carb. I want to do what Shepard did on his but I can't find a manifold that has such a large hole spacing 80mm center to center. Thanks, Greg
This sounds good, but have you considered the Weber 2 stage carb? I had one on a Datsun may years ago, too big?
My suggestion, being a Snowmobile Mechanic, is this. Take a plate of allum, thickness to be determined? Make it taller than needed, but wide enough to make the seal? Then drill all the way threw the thin edge! So lets just say a plate about 4" wide, 6" tall and 1/2" thick? Drill the hole threw the bottom edge and tap it for 1/4" Iron pipe thread! Then just put 1/4" IP X hose barb fittings on it! Run your coolant threw the allum plate! Next drill your 80mm spaceing! Then at like a 45, drill the othere bolt patteren (it will be called a HD pateren) Tap and install studs to hold the rubber mounting flange. Then in the very center just drill a 2" (?) hole for the center bore with a hole saw drill! Now if you need another vac port, just drill into the side edge and tap 1/8" pipe tap and get a hose barb fitting! Now my question is why a 32mm?If you still lack top end, Why not a 40 or 44mm? What has your fuel milllage done?
