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Woody
V4 Guru

United Kingdom
2377 Posts

Posted - 02 Jul 2011 :  10:34:42 Show Profile Reply with Quote
Well, I am old enough to have seen the first showings, but not quick enough to answer.
One other item from the series is the "Windcheeter" jacket worn by the pilots.
Still available today - http://www.scenemenswear.com/index.php/baracuta-g35-dean-windcheeter
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James Ranaldi
V4 Guru

United Kingdom
1352 Posts

Posted - 02 Jul 2011 :  23:24:10 Show Profile Reply with Quote
Hi Pete,

Fantastic model.. . very impressive. I too remember the original series.

Is the tail rotor driven by an electric motor ? How do you synchronize the tail rotor speed with the main rotor?

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pchristy
V4 Guru

United Kingdom
1737 Posts

Posted - 03 Jul 2011 :  10:17:18 Show Profile Reply with Quote
Hi James,

The whole thing is powered by a 20cc spark ignition 2-stroke, and runs on normal unleaded (plus oil, of course!). There is a reduction gear between the crankshaft and main rotor. The main rotor runs at around 800-1000 rpm. Its quite slow by model standards, and off the bottom of the scale of all the optical tachos that I've been able to use on it, so that head-speed is a bit of a guess! The tail rotor is driven by a wire shaft, coupled to the main reduction gear. Because the two are coupled mechanically, synchronisation isn't a problem. The tail rotor is variable pitch for control. The main rotor has both collective and cyclic pitch control and is stabilised by a mechanical flybar on the rotor head, which uses features from both Bell and Hiller stabilising systems.

Its quite big and heavy, and does look good in the air. This video was taken at the Scottish Nationals near Aberdeen last year. This was before I'd finished redecorating it, so the paintwork around the cabin was still a bit rough at that point:

http://www.youtube.com/watch?v=-Md_kSNh6Tw

It has real "presence"! Unfortunately that petrol motor (essentially a strimmer motor!) is not particularly smooth and generates quite a bit of vibration! Earlier this year, one of the push-rods connecting the swashplate to the servos sheared in flight - probably due to vibration fatigue. Luckily the model wasn't very high, but I lost control of the fore-aft cyclic, and the model slid into the ground backwards. The tail-boom was extensively damaged, but I now have a replacement awaiting painting. However, I will need to go round it and replace every push-rod in it as a precaution! This is time consuming - just as the cars are - and since I need the cars to get to and from work, they have had to take priority!

I was delighted at how many people remember "Whirlybirds"! I thought it was just me having rose-tinted glasses of my childhood! And thanks for the link to those jackets, Woody! Somewhere I've got an original 60's SAAB patch for a rally jacket, which would look really good on one of those.....!

--
Pete
"Duct tape is like the Force: It has a light side and a dark side, and it binds the Universe together!"
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James Ranaldi
V4 Guru

United Kingdom
1352 Posts

Posted - 04 Jul 2011 :  19:35:51 Show Profile Reply with Quote
Amazing. Thanks for the comprehensive reply Pete. Fantastic video and 10 /10 for the landings.

A wave from the pilot would have been good

Cheers
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pchristy
V4 Guru

United Kingdom
1737 Posts

Posted - 07 Jul 2011 :  11:19:04 Show Profile Reply with Quote
Well the 34ich is now on the car! I've only driven it around the block so far, but first impressions are that it is a LOT more responsive to the throttle, and the tickover is amazing! I initially set it up by ear, and when I checked it with a tach, it was idling quite happily and smoothly at 700 rpm! It was so slow that I thought it had stalled a couple of times! I've set it up to a more realistic 800 rpm now, and intend to drive it into work today (20 miles each way).

The only remaining issue is how to secure the air filter. The standard one fits over the carb nicely, but the carb doesn't have the little bridge piece that the filter is meant to screw into! I had hoped to swap the one off the FoMoCo over, but it is very solidly riveted in place, and I don't want to destroy the original carb!

At the moment, I've done another bodge using some more old fly-bar plus some metal strap. The fly-bar goes across the carb and is secured by a couple of 3mm nylocs on the outside (so nothing can drop down into the engine if it comes loose!), which holds the strap in place. The strap is bent to form a bridge (as per the original) and tapped to take the securing bolt. The problem is that the strap is too thin to thread properly. It will hold for a while, but isn't going to be a permanent fix.

What have you done about an air-filter for yours, John?

The carb also has the wrong idle jet in, so the needle is quite a long way out. I've ordered a new jet, which will hopefully arrive soon. I also intend to replace the awful "bent-rod" link between the torque rod and the throttle arm on the carb with a proper ball joint one.

Oh, and the choke linkage fouls the brake servo vacuum pipe! Luckily, like most Webers, it doesn't need much choke, and I have enough movement to bring the fast-idle up to a reasonable setting, but its something I must sort out in the longer term. What it really needs is a 90 degree adapter to screw into the vac plate instead of the straight one currently there!

Enough work there to keep me busy for a while, I think....!



--
Pete
"Duct tape is like the Force: It has a light side and a dark side, and it binds the Universe together!"
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pchristy
V4 Guru

United Kingdom
1737 Posts

Posted - 10 Jul 2011 :  08:53:43 Show Profile Reply with Quote
The temporary bodge I used to secure the air filter has now been replaced by a proper metal bridge made by a friend with access to a machine shop! Also the awful "bent coat-hanger" throttle link between the torque rod and carb has been replaced with a decent ball joint affair, and a new idle jet fitted.

The car is running well on this combination. I haven't refilled the tank yet, so I don't know what its done for the economy, but its certainly much more responsive to the throttle. I don't know that its much faster - it feels a little bit, but not a huge amount. But it certainly revs more freely!

Its got a very slight "hiccup" when the throttle is just cracked open. Its not there at tickover, which is exceptionally steady, or when the throttle is more than about 20% open, but when doing around 30 on a very light throttle, I can just feel it misfiring a bit.

It maybe there's still a small piece of crud in there - it was pretty grotty inside! But I'll run it around for a bit and see what happens.

Not being an expert on these carbs, I'm unsure which jet might be responsible for light throttle mixture. Any suggestions gratefully received!



--
Pete
"Duct tape is like the Force: It has a light side and a dark side, and it binds the Universe together!"
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john-saab
Administrator

United Kingdom
2648 Posts

Posted - 10 Jul 2011 :  12:21:10 Show Profile Reply with Quote
Good work Peter.
I have fitted a 2 stroke air filter..it needed work but sits well ontop of the carb and bolts to the 2 rocker covers.


"The carb also has the wrong idle jet in, so the needle is quite a long way out"

I have the same issue..i upped the idle jet from 50 to 55 and the needle is in a little further in but it's running well..I can't see that it will hurt but I also have that slight hiccup just as you build the revs..a visual check with a torch looking into the carb shows that at that point of the hiccup the fuel isn't vaporising properly..a drip of neat fuel drops into the body and that causes the hiccup..once the revs are up the fuel turns to an invisible mist again and she runs fine...winding that needle out does nothing to help so i'm guessing that the air idle just isn't correct???

"Oh, and the choke linkage fouls the brake servo vacuum pipe!"
Again same here..i found a thinner walled vaccuum pipe helped


current V4 models..'72 95 (The Flying Banana),'72 96 (Bridget),'74 95 (Veronica),'74 96 (The Brown one)NOW SOLD..destined for greater things

Edited by - john-saab on 10 Jul 2011 12:45:29
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pchristy
V4 Guru

United Kingdom
1737 Posts

Posted - 10 Jul 2011 :  16:39:19 Show Profile Reply with Quote
Thanks, John!

Now that I've got the proper bridge made for the carb, the standard filter fits just fine. There's only one securing bolt to the the rocker boxes - on the passenger side - but the crankcase breather pipe helps to locate the drivers side. Together with the main central fixing bolt, it all feels quite secure now, so I'm happy to drive it a bit farther afield!

The hiccup is slowly spreading further up the rev range. Its barely noticeable unless you are driving, so I reckon there must still be a bit of crud in there. If I get chance tomorrow, I'll open it up again, and drop the jets back in the ultrasonic cleaner. I've finally managed to get the emulsion tube out - or rather my friendly mechanic has! It was seized in there solid when I got it, and although is been hit with both compressed air and carb cleaner, it hasn't had the ultrasonic treatment - yet!

My friend is trying to locate a vac adapter with a 45 degree bend in it, to help with the choke fouling problem. He's found a 90 degree one that fits, but that fouls other things, so a compromise is needed. Luckily, it barely needs any choke in the current weather, but best be prepared for winter, I think!



--
Pete
"Duct tape is like the Force: It has a light side and a dark side, and it binds the Universe together!"
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pchristy
V4 Guru

United Kingdom
1737 Posts

Posted - 17 Jul 2011 :  12:04:14 Show Profile Reply with Quote
My friendly mechanic has now modified the brake servo take-off, so that the pipe now clears the choke linkage:



Basically, he cut the metal adapter that screws into the vac plate, ground one side to 45 degrees, and then tig welded it back together!

I now have full choke action without it fouling the brake servo pipe!

I filled the tank up yesterday - the first refill since fitting the Weber - and its done 35 mpg, despite being driven fairly vigorously whilst evaluating the carb! This is significantly better than I was getting with the Autolite, as well as the car being much more responsive.


Here's a view from the other side, where you can also see the new "bridge" made by another mate, that allows me to screw the original air filter back on!



Still got a very slight stumble on light throttle, and the idle needle is wider open than it should be, so I will need to invest in some bigger idle jets before its perfect. I'm currently running a 50 jet, so I'm going to get a 55 and a 60 and try them.



--
Pete
"Duct tape is like the Force: It has a light side and a dark side, and it binds the Universe together!"
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john-saab
Administrator

United Kingdom
2648 Posts

Posted - 17 Jul 2011 :  12:42:43 Show Profile Reply with Quote
Try a 60 peter..i'm using a 55 and it's almost there..if you don't like the 60 then i will buy it off you and try it on mine.
I can't really see the new breather but if it works then that's good.
Is that rocker cover breather pipe silicone or just bound with tape?

current V4 models..'72 95 (The Flying Banana),'72 96 (Bridget),'74 95 (Veronica),'74 96 (The Brown one)NOW SOLD..destined for greater things
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pchristy
V4 Guru

United Kingdom
1737 Posts

Posted - 17 Jul 2011 :  14:17:12 Show Profile Reply with Quote
OK, I'll go for a 60 then!

Yes, it was difficult to get a good view of the new breather! I should have photo'd it before I fitted it, but I was keen to get it installed!

Before, the servo pipe came vertically up and actually touched the choke linkage. I could get a bit of choke, but not much. Now I can pull it fully on without fouling!

Yes, the breather pipe is silicone. It came with the pipe set I got for the 96 when I "siliconized" it, but as the 96 has a 28/36, it didn't fit. On the 96, I used one of the bits of pipe that was probably meant for the automatic choke on a standard car, but which my car doesn't have!

I'll probably fit a silicone pipe set on the 95 before winter. I don't know how much anti-freeze it has in it, but a refill is almost guaranteed to finish off any weak pipes. The visible ones all look OK, but its that one behind the water pump that worries me! Its almost impossible to fix if it goes on the road!

BTW John, have you got your lift fitted yet? I'm off to Italy to support Mark at the World Champs in the middle of August, and will be away for nearly a month (staying in Italy for our wedding anniversary!). If I can get the car to you before we go, it would give you plenty of time to have a look at the floor!

Most of it looks OK, but there is a hole (non-structural) between the sill and the panel in front of the rear wheel on the passenger's side. I'm also not too impressed with the area where the front wheel arches meet the floor. It passed its last MOT with no advisories, but I'd like to get the underside tidied up before the next one.

Is mid-August to early September a possibility?

Cheers,



--
Pete
"Duct tape is like the Force: It has a light side and a dark side, and it binds the Universe together!"
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john-saab
Administrator

United Kingdom
2648 Posts

Posted - 17 Jul 2011 :  17:00:31 Show Profile Reply with Quote
Sorry Peter..I thought I had posted a reply somewhere else..the workshop building is being renovated inside and out, the work starts in about 3 weeks so we are clearing out ready for the work to start..once it's finished we will be fitting the lift, building new storage and sorting the floors + other work so unfortunatly that's pretty bad timing..I will let you know when it's all done and i'm ready to have a look but to be honest with me missing a large part of this year due to my back i'm VERY behind on other work so it's looking like it may well be winter before I get a chance..sorry.

current V4 models..'72 95 (The Flying Banana),'72 96 (Bridget),'74 95 (Veronica),'74 96 (The Brown one)NOW SOLD..destined for greater things
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pchristy
V4 Guru

United Kingdom
1737 Posts

Posted - 17 Jul 2011 :  18:46:23 Show Profile Reply with Quote
OK, thanks for letting me know! I think it will need some attention before MOT time in December, but I can probably find someone to do it locally.

Cheers,



--
Pete
"Duct tape is like the Force: It has a light side and a dark side, and it binds the Universe together!"
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Derek
V4 Guru

United Kingdom
1779 Posts

Posted - 17 Jul 2011 :  21:31:51 Show Profile Reply with Quote
A current thread, sort of, on the Yahoo Vintage Saab forum has the following.From Bill Trench - I was looking into putting a PCV valve on my Bugeye motor and hit on the Wikipedia site . The picture they show for an example is of a V4 on a
96. Interesting....
http://en.wikipedia.org/wiki/File:Pcv-valve.jpg

Reply from Martin Hilvers

Guess whose...

That PCV valve is modified, I cut the top off at a 45deg angle and
welded the cut off piece back on so it now is at a 90deg angle. Otherwise the hose from the valve cover would not fit, too tight against the Weber carb.

Sound familiar?


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pchristy
V4 Guru

United Kingdom
1737 Posts

Posted - 17 Jul 2011 :  23:17:27 Show Profile Reply with Quote
Well spotted! I hadn't seen that, but yes, the same problem!

We were originally going to make mine a 90 degree bend, but thought that might foul somewhere else. We compromised on 45 degrees, and that has worked perfectly!



--
Pete
"Duct tape is like the Force: It has a light side and a dark side, and it binds the Universe together!"
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