Thanks: Link to page 4 of Anzani History Scroll down to the grey box for mention of Bill Tenney, navigate back to page 3 for a little more about the origins of the Anzani outboards
Likes: 0
The British Anzani and Harrison Relationship Spanned the Ocean?
Link to page 4 of Anzani History Scroll down to the grey box for mention of Bill Tenney, navigate back to page 3 for a little more about the origins of the Anzani outboards
Last edited by Mark75H; 08-13-2005 at 10:32 AM.
British Anzani - The Company History To 1980
Last edited by Mark75H; 08-13-2005 at 09:53 AM.
British Anzani - Lucas Magneto Swivel And Timing Lock System
The following items make up a British Anzani for Lucas magneto adapter to engine platform incorporating magneto swivel for ignition timing and bolt friction lock. The magneto's adapter plate was quater inch soft grade aluminum and the rest of the friction swivel parts were even thinner aluminum that failed a lot from my understanding. Racers either made their own repairs, replacements. or did some other more durable mousetrap of their own to replace that swivel lock.
The pictures show lots of old storage grunge left there by smoke damage to the part in Bill Tenney's garage fire way back when and I have yet to treat and shine those parts amongst others that happened to as well.
Enjoy the Jpegs. I have full size tracing for those that could use them, but getting them are by fax and pre-arrangements that are quite limiting time and cost wise.
Final Anzani Magneto Swivel Plate and Friction Lock
Final pictures of magneto swivel plate and friction lock Jpegs.
TYPICAL BRITISH ANZANI CLASS "A" OR "B" GAS OR ALKY CONNECTING ROD ETC.
Featured in these two photos are typical British Anzani one piece connecting rod and the assembly that ties it to the built up / replaceable parts crankshaft. Nothing low tech about this assembly to the crankshaft. The rod is typically the one piece with a un-remarkable but hardy bronze and with oil slotted slotted "bushing" at the small end for real solid support at the small piston pin end.
The remarkable big end of the rod uses wide rollers with the bearings running in a extremely light and well fitting alloy, one piece bearing retainer. The big end crankpin is replaceable with tapered ends for maximum adjustment and alignments when constructing or reconstructing the crankshaft from its many sections. Holding together remarkably well as a gas stock racing engine, things got a little dicey as RPM and horsepower went up when methanol with percentages of nitromethane incorporated into the methanol and caster oil got over the 12-14% range causing misalignment problems from the sheer power or when you simply dumped the boat/engine on the racecourse.
These were times the rods themselves too would and could suffer, being that the rod small end would look like it is "drooping" that is bending over about 1/3 the way down from the small end, either necessitating straightening on a jig or replacement. Their snap off the small end seems to occur when the rod gets a 45-50 degree droop, loosing all kinds of power ending the usefullness of the engine until salvaged and repaired if possible. It was possible for a separating connecting rod to end the life of a crankcase but a cast iron block as you see from some previous pictures is quite another matter with the cast iron block repairable after quite a blast!
Putting too much starting fluid could have the same effect as well as not using a strap wrench on the flywheel to counter taking off or putting on the flyhwheel nut. It was easy to tell alignement simply by rotating the motor looking for "binding" as that is what a piece together crankshaft, connecting rod to pistons alignments exhibits when it is out of alignment.
THE TYPICAL ANZANI "A" AND "B" PISTON PINS AND ROD BUSHING
The typical and different "A" and "B" piston pin lengths of same thickness that came if open ended fairly thick walled hardened steel, if one end closed the pin would be thinner walled, so you have lighter and heavier versions of piston pin for "A" (250CC) and "B" (322(Alky) &-same as for 322cc for the 344CC(Gasoline racing B stock). The bronze busings had a slight taper begining for rod installation and absolutely square for piston pin to piston wrist pin boss/hole alignments. There was no difference in the bronze busing bearings arrangements of Anzani "A" or "B" engines, they were the same from big end to small end.
One remarkable thing about these engines is that though built with very close tolerances and made from castings, forgings and machinings of components, there was an absence of the "balancing" of race engine components you would think you would find on a outboard racing engine. Many of the Alkys later on were similar in this without balancing state you would think would have been there, but wasn't until the development of major power, sky high rpms and high speeds never expected that high brought on very careful and precision balancing of components not seen when they first entered Alky classes in North America, where everyone else had to play catch up from their appearance for quite a while. No one was really sure where all this would have went, had not Anzani come to a production end and went out of business and disappeared not long afterward with Harrison (Burmingham Metal Products) extending the Anzani racing life a little while longer after that.
From about 1959 to 1970 were remarkable years in loop race engines in outboard racing of which British Anzani was just one of the earliest ones.
Driveshafting That Power - British Anzani
Originally British Anzani(s) came to the market as factory built stock racing engines produced by the company no different than Mercury and others of that era. Once the powerful Anzani stock racing gasoline engines where excluded from factory produced racing stock and aligned with into the Alky ranks, you could sure see where the engine was going by its driveshaft thickenesses to deliver the power to the Mark I and later the Mark II gearcases with selected props to do the pushing. The following are comparrison pictures of the Gasoline version of the a-typical Anzani Driveshafts and with them the change for Alky (methanol/nitromethane fueled). For keeping the driveshafts cost down as with the crankshaft and lower gearcase connecting stubs, all connectors and stubs were kept squared as opposed to splined, splined would have increased component costs considerably higher.
The Preferred Fuel Pump - Omc - For Anzani Use
Previous pictures on various other areas of the board showed the British Anzani B Stock racing and also British Tenney spec'd A and B Alky Anzani(s) using crankcase pressure feed pressurizing the fuel tank forcing the fuel in the stock racing outboards case to a round slide Amal Monoblock carb which through its needle vale and float system would cut fuel and allow more in as needed as a pressure feed carb. Bill Tenney and others found that there was no way to fuel a very fuel hungry Anzani with methanol, so a lot of carbs were tested coming down to a suitably sleved Vacturi as those used on "C Service" racing engines from the 1930s became the prozed candidate for A and B Class Alky Anzanis as well. Vacturi(s) being a gravity feed carburator that fed from and overhead tank was way too touchy pump fed slamming components shut and being too sensitive to change Bill Tenney and his engineers figured out how to use 1 to 3 Italian DelOrto remote fuel bowls to accept the pressure from tank fuel mix then transfering the fuel lix to the Vacturi as if an overhead tank was still there, with large flow and very low pressure. Other than sleveing and stud adapter plating the Vacturi suitably to suit the Anzani's cast iron blocks on board carb inlet port. This was fine for a while until the Vacturi's cork floatbowl float sunk causing ever manner of flooding misery, which you either dried and recoated or changed out.
Around this period the racers and preparers of Anzani(s) out in the North West USA got very tired of the whole DelOrto float bowl and Vacturi with a sinking floatbowl cork affair and decided that a much simpler system? would be to have a high volume OMC remote pulse type fuel pump found on a whole host of OMC bigger cubic inch applications had the fuel capacity and fuel pressure to keep that Vacturi overfull so a simple spill over system was developed in the Vacturi, dispensing with the fuel inlet, needle, seat andfloat having excess fuel in excess returning to the fuel tank for a constant flowing non-pressure at the tank fuel system without the pain of having sinking corks and flooding conditions that plagued the previous system. It was fond soon after that this pump also allowed for extra carbs to get fuel feed like the Tillotson HLs that also had an onbroad fuel pump to take its fuel from the stream the OMC pump facilitated, that also started sprouting off Anzanis like their exhaust near look alike Harrisons with two, then four, plus add the Vacturi as the main! It helped to feed them all.
The following, that workhorse, the common OMC (Johnson/Evirude) remote, diaphramed with fuel bowl and extra filter, fuel pump.
They are a great replacement pump for use on a lot of other engines in fuel pressure feeds from pump to the fuel floatless spill over return to fuel tank fuel pumping and distribution systems.
"COD PIECE" - FOR THE BRITISH ANZANI MAG DRIVE GEARS CAN BE NASTY!
In the 1950s a lot of engines in many catagories had gear drives for timing and ignition rotation. In outboards, during the early formative 1950s Mercury Outboards had its KF and KG 4 cylinder engines with gear driven magnetos. So too were engines like British Anzani Unitwin racing outboards in 250CC, 322CC and 344CC. Under their heavy steel and chromed over flywheels and polished aluminum rope plates was this big ring gear from alloy steel and on the matching outside on its Lucas magneto and platform was the magneto fiber product a type of bakelite gear of equal size and same mesh as the flywheel gear. Fact was then as it is still now, you want very exacting ignition timing from a mechanical magneto, you most certainly want a timing gear set for racing at high rpms that many loop engines go to and certainly not a cogged belt system, that some engineers frowned upon but they were proving to be not too shabby either as engines that would come to use them were also very competitive in the racing classes they entered validating high speed belt technology no different than timing gears, cogged belts being somewhat not as dangerous as a rotating high speed and exposed timing gear! To be on the safe side people payed attention to their ignition drives and in Anzani's case they cast what most call the Anzani "Cod Piece" as it very much shields the users of the engine from a spinning timing gear that could very well eat a fit of flesh, should it come in contact with your body, with their eat and spit sides of the dual gear drive for that Lucas magneto! Earlier pictures showed the flywheel and magneto drive gears and here now is its detailed picture of its thick cast aluminum gear drive shield aka the cod piece! Enjoy the pictures of protection!
SOME 344cc "B" STOCK RACING ANZANI DIFFERENCES FROM THE 322 ALKY
Anzani using the common front crankcase used 2 different cast iron block castings to enter 4 different classes, 2 Stock racing and 2 for Alky A and B racing, with a slight twist.
This was apparent when Anzani made its B stock racers at 344cc displacement or otherwise shipped Bill Tenney of Crystal Bay, Minnesota the B Alky racing block bored to 322cc.
At the carb mounting plate that served that also served as the retaining plate for half of the opposite side of cylinder air/fuel transfer ports also used the carb bore port studs for some extra support that also carried the barrel shape, diameter and attention to the air fuel flow that not only went to the piston ports but also a hard 90 degree passage left, to the opening of the crankshaft rotary valve.
The red painted plate is typically for the Anzani 344cc B Stock gasoline racing outboard with the perfectly round opening for the Amal Monobloc carb to sit on. The metal grey plate was specifically shaped to feed differently the 322cc bored B Allky block to facilitate the mounting of an aluminium adapter plate on top with machining done to adapt the Vacturi AO500 (OMC C-Service racing used carb) with a custom machined sleaved venturi to that aluminum adapter plate to the steel late in these pictures to the Anzani bored 322cc Alky version export block.
Quite complex for a thin steel plate that was similarly used on 250cc and 344cc Gasoline fueled Anzani Unitwin Stock racers and then there was the Anzani Alky (methanol + ) fueled engines with 250cc, 322cc. Some 344cc engines seen Alky action as well but reports are few of how much better than the 322cc they were?
For a simple plates that these look the part, their parts were much more critical than is apparent.
Enjoy the pictures.
There are currently 1 users browsing this thread. (0 members and 1 guests)
Posting Permissions
Bookmarks