Bultaco persang issue

Aldo and I have been playing around with an old Bultaco Alpina, trying to get it to run after it's been sitting in a shed for several decades. Stuck a bit of oil down the spark plug hole and kicked it over a few times lubricate the bore and rings. It has plenty of compression and fires up if we squirt a bit of fuel down its throat and kick it over, but the fuel system isn't working so it dies after a few seconds. I just cleaned a whole lot of molasses looking shit out of the carby, and got the fuel tap flowing properly, so hopefully it'll actually keep running when the carby goes back on.

I have a question about oil levels though. The gearbox and primary drive have different oil in them. I found the refill quantities on the web so changing the oil isn't an issue. But topping it up is a mystery because there doesn't appear to be any way to check the oil level once it's in there. There's no dipstick on either of the fillers, and you can't poke a screwdriver or something in because there's internal works in the way. I can't find any sight glass or level check plug anywhere either. Google wasn't any help. Are there any Bultaco aficionados out there who could give me a clue? It would be handy to be able to do regular checks, especially on the primary oil because as someone mentioned earlier it can disappear into the crankcase if the shaft seal isn't perfect.
 
This is a guess but I think The Floods, eg Bert was the distributer. He had sons who were in the bike business in Vic.trever and Gary
https://www.bikesales.com.au/editorial/details/rip-bert-flood-updated-with-funeral-details-13192/
 
Hi Cam

There are no level checks built into the bike. The refill is by oil volume. You will then have to invent your own method to test levels as you go along.  Yes, primary drive oil can be sucked in through the crank seal. Which is a consideration if the bike has stood for a while as the seal lips may stick/tear or have become hard. (the bike will run like a pig if it happens).

The gearbox oil is held in place by the central gasket, which though large and thin isn't usually problematic.

HTH Paul.
 
Good onya Vince. That's the first time anyone has ever referred me to a dead bloke for further Info. I'll organise a s?ance and let you know how I get on.  :D

Thanks Haggis. That's the conclusion I'd come to. Thought I'd ask the question in case I might have been missing something. Wouldn't be the first time I'd non seen something obvious.
 
pursang = pur-sang = true blood or thoroughbred (a horse breed best known for its use in horse racing)

Ettore Bugatti (an avid horse lover) f.e. named his car creations Pur Sang
 
It was a bit of an education working on an Amal carb, figuring out what all the jets and galleries do. My usual fix for Amal carbs is to chuck them in the bin and fit Mikunis. But this Bultaco isn't my bike.

The carb is actually in pretty good condition. The slide isn't a loose fit like I've found on other Amals. So it looks like the bike hasn't done much work. I reckon it's spent most of its time sitting in a shed. Main issues are dirt and rust.
 
Got the old Bultaco Alpina back together yesterday.  :D

Runs OK when you open the throttle but needs a bit of carb tweaking to get it to pull away from idle smoothly. Seems like the idle jet might be blocked. Maybe I missed a bit of crap when I cleaned the carby. Still learning about Amal carbs.
 

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Don?t think it?s crank seals- that stops primary compression which leads to poor / not starting.
If it?s revving like mad it?s got to be carb/ cable related. We used to run hard chromed brass slides in Amal?s on grasstrack bikes to stop them sticking / binding. Are you using modern two stroke oil with lower ratio?
Tickover set too high Or flooding will also cause overrun into corners. Not a fan of Amal?s full stop, they are cheaply built and prone to warping, leaking and wear out . Decent Keihin or Mikuni is the way to go if rules allow.jason
 
Bike starts OK but won't idle unless the idle screw is wound in far enough, but then it idles at about 2000 rpm. Try to set the idle lower and it just stalls, which is why I suspect an idle jet problem.
 
Whats the high idle sound like if its tinny and bangs its probable lean any air leaks around the carb had some experianve with montesss very hard to ride  constant wheelstands with bearly any throtal and a clutch twice as hard as the worst laverda clutch
 
In my experience if the idle screw has to be wound way in to achieve a [poor] idle it does point to the pilot system, as it is likely pulling blobs of un atomized fuel up through the needle jet to run. Often overlooked is the air side of the pilot circuit, that little hole in the bellmouth clogs pretty easily with dirt/corrosion.
 
Vince said:
Whats the high idle sound like if its tinny and bangs its probable lean any air leaks around the carb ...
Click to expand...

No tinny sound. Just sounds like a normal engine that's idling too fast.

I've never been a fan of Animal carbs, and this one isn't changing my opinion.
 
I'm assuming we're talking about a concentric Mk 1 here and not the previous Monobloc. Amal made a two stroke specific model where the pilot jet is in a different position on the air circuit. Loads of information online about this, sounds like the pilot jet is blocked to me. Just strip and blow the crap out, a weekly task on my old trials bikes. Enjoy.
 
Hi Cam

Also check your float. They can be problematic (a 'stay-up' float is available). Usual drill - dunk it in water and watch for bubbles.

BTW - Your Amal will almost certainly be Spanish made.

Paul

Biggest problems I ever had with carbs on Bultys were the late models with Bing. Bloody Bing things.
 
Slightly off topic My experiences of a 360 pursang are limited to chasing one on a sherpa 250 and hitting a mound of earth across the track at about 60 mph Flat out I soared into the air unable to get the bike front wheel up enough and the bike followed me into the air. I remember looking down with the bike rapidly approaching me on the way up My thoughts were this is going to hurt I was right it did a lot One badly broken arm twisted round the back of my neck and all four ligaments in the left knee torn apart I hit the deck like hitting a big black cushion no sharp edges but it did hurt. An ambulance later and six months in hospital on non weight bearing leg post a big op that had only a 50/50 chance of repairing the knee (1976 this) all was good again knee not so much at first. so bought a Land rover as surrogate sherpa-- didnt work, so ended up back on bikes Thats the lot, What I have learned is choose your suspension to suit what you are actually going to do. :o
 
Seriously bad stack that one! That's a very long recovery. Off-road accidents can be very serious indeed. i have friends who raced enduros and they have some ugly injury tales to tell.
 
BobSol said:
I'm assuming we're talking about a concentric Mk 1 here and not the previous Monobloc. Amal made a two stroke specific model where the pilot jet is in a different position on the air circuit. Loads of information online about this, sounds like the pilot jet is blocked to me. Just strip and blow the crap out, a weekly task on my old trials bikes. Enjoy.
Click to expand...

The point in the idle circuit which is prone to blocking either from old fuel or grit is the transverse passage behind the idle air screw. It can be poked clear after removing the airscrew using very fine wire. Solvent squirted in there should come out the idle mixture hole on the bottom of the carb throat.
 
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