Thanks: 
Likes: Great looking work, what type o-ring material will you use ?
Mike
Great looking work, what type o-ring material will you use ?
Mike
The "80,s" 4 cylinder carbs mite work?
The cover is the TII X and I intend to use the carb from that unit which is a Tillitson float carb. Uck! I received a set with the cover, so we will try them first. They were fitted with a shallow float bowl and modified float. I will convert to Alky and make adjustable by rotating the bowl 180 degrees and fitting with adjustable high speed jet. Why rotate, the starter is in the way to make adjustments, however the bigger issue would be the float sitting on the needle and not letting the float drop to let in fuel. If they are a problem, I will use Tillitson diaphragm units. The o-ring for head gasket will be the orange silicon in the 60 durometer range for oils alky, and high temp. Pics are of the final, I think, patterns required for the project. They are the coil holders that bolt to the sides of the heads, the new top main cap required because of the smaller crank bearing bore size mentioned before and to tighten up the fit of the trigger. The power head to tower adapter required because of the lower carb to swivel pin interference. The Jones tower has the bracket bosses on the outer sides of the housing, opposite of the Mark 75H system. The patterns went to the foundry today so I should have those parts in a couple of weeks.
Had some time the last 2 weeks to get deeper into the machining of the mid case. Spent much of the time checking dimensions and alignment for proper material removal. centered up good could make some miner changes to mold if I was to cast another, but nothing to impact this project so we will press on. More pics of the machining. Lots metal removal. What you call making chips?
Making chips
Concern about converting carbs to adjustable needles - not recommended! With one barrel per cylinder it will be impossible to tune properly unless you peak each with a test wheel - nearly impossible to accomplish without a sophisticated test tank or better yet a dyno. Once tuned, all is OK until one vibrates free. This could mean a soggy cylinder, or worse, one smoked piston. Years ago I converted to fixed jets beause of scenario #2....
Otherwise, your machine work is coming along nicely, a sign of serious progress. Anytime a one-off is built, alot of chips are generated to be sure! Keep up your good work, this truly is a beast. A big, beautiful beast!
Tim
Like many of us "old geezers" I began my Merc experiences with adjustable jet motors, and they made good sense on a two cylinder Hurricane. When I went to a KG-9 it made a bit less sense, holding on at full throttle and dialing in that second carb. But going to three or (gasp!) six carbs means it's time for fixed jets. And (as stated above) if an adjustment vibrates away from where it was set, disaster could result.
Agreed?
Jeff
There's always the option of a second man in the boat adjusting the carbs while someone steers the boat. Not a viable option!
When we were both 17 years old, Bill Seebold Jr. suggested that I "drive" his D-Hydro while he set the carbs.
Bill Sr. nixed that idea in a big hurry!!!
Probably saved 2 young bucks from getting wet, plus saved a very good rig from getting busted up.
RE: Chips
Dick you could probably get someone to clean your shop for free. Just let him keep the chips he sweeps up!
Have to agree with Tim. This is a thing of beauty you are creating here
To all, thanks for the compliments.
I have not found alcohol carbs that difficult to dial in as long as the floats hold. Dealing with alcohol is no where near as sensitive as gas. The ratio of gas to air being 14:1 verses alcohol at 7:1 make the adjustments less difficult. I set rich and use plug color for adjusting. If the carbs are all made the same they all set the same. Gene send me your e mail address to rkaustin@frontier.com. Starting on the heads. Now need to weld the front cover for the new reeds and re machine mateing surface for line boring.
If this were mine, I'd use a standard crank case cover. I wouldn't need the 6 carb setup, I'd want it as close to the original Loopers as possible. Amazing machine work!
Fabulous work Dick - it looks positively fearsome!
You might consider splayed 1-bbl carbs similar to the 666 if vertical space is an issue. Better yet, you might consider six two-barrels which would look freaking awesome. Those cylinders are big, so they might even work! I will post mounting centers from my Mod-50 for OMC carbs. You shold look at Merc V6 two-bbls as well. A 12-pack = Woof!
Tim
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