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tommygoldy
V4 Fan

142 Posts

Posted - 08 Feb 2014 :  20:43:16 Show Profile Reply with Quote
quote:
Had an on line chat with FRC today and he confirms that the 27mm ICH is on the shelf, including fitting kit and manual choke..£175 delivered (UK)


That sounds like a good deal... However, I've got a friend who's a Weber dealer so getting a price from him first. FRC would certainly be my next port of call.
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pchristy
V4 Guru

United Kingdom
1737 Posts

Posted - 09 Feb 2014 :  09:58:57 Show Profile Reply with Quote
Interesting! I haven't seen 34ich carbs listed new anywhere for years. I thought they were out of production!



--
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
2647 Posts

Posted - 09 Feb 2014 :  16:15:18 Show Profile Reply with Quote
Anthony said he had them on the shelf (with the correct 27mm bore)
I don't need one at the moment as I have a spare that just needs a pump spring.

'72 95 (The Flying Banana),'72 96(Bridget),'72 96 (green one)'73 96 (Vernon),'74 95 (Veronica)
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tommygoldy
V4 Fan

142 Posts

Posted - 11 Feb 2014 :  11:50:04 Show Profile Reply with Quote
Carb is on order. :)
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tommygoldy
V4 Fan

142 Posts

Posted - 16 Feb 2014 :  18:33:23 Show Profile Reply with Quote
Got the carb. Looks nice. Paperwork describes it as a Ford 1.6 OHC kit. It's the correct model and choke size. No choke cable but there's one in the car already (not connected) - perhaps not the first time this mod has been done.

Standard jetting as follows:

Main jet: 155
Air corrector: 175
Emulsion tube: F6
Idle jet: 50
Pump jet: 50
Needle valve: 175

It also includes a 160 main jet - the instructions advise fitting this if "any hesitancy is noted in drivability". Based on others experiences I might try a bigger idle jet too at a later date.

Have had a look at the car and fitting looks simple enough. Only one query, and that's what to do with the two breather hoses connected to the auto choke on the FoMoCo carb. Shall I just lose them and seal ends? Any good ideas for terminating them neatly?
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pchristy
V4 Guru

United Kingdom
1737 Posts

Posted - 16 Feb 2014 :  18:54:57 Show Profile Reply with Quote
I think you'll find that those hoses connected to the auto-choke are hot water hoses. The auto-choke detects from the water temp when to turn off. Its a long time since I replaced an auto-choke, so others will correct me if I'm wrong, but I think you need to join the two hoses together with a bit of pipe and some jubilee clips.

If the idle mixture screw is more than two turns out to get a decent idle, you will need to increase the idle jet size. The idle jet controls the mixture up to about half throttle, and if the idle mixture screw is more than two turns out, it will be too lean in the mid-range. Most people have settled on a 60 size jet, which seems to get the setting about right (between 1.5 and 2 turns is ideal).



--
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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tommygoldy
V4 Fan

142 Posts

Posted - 16 Feb 2014 :  18:58:50 Show Profile Reply with Quote
quote:
Originally posted by pchristy
I think you'll find that those hoses connected to the auto-choke are hot water hoses. The auto-choke detects from the water temp when to turn off. Its a long time since I replaced an auto-choke, so others will correct me if I'm wrong, but I think you need to join the two hoses together with a bit of pipe and some jubilee clips.



Ah - silly me! Glad I asked, although I suppose I would have worked it out in the end...when water poured out of the disconnected hose

Thanks!

Edited by - tommygoldy on 16 Feb 2014 18:59:52
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Mr Burrrrrrrrrrt
V4 Fanatic

United Kingdom
326 Posts

Posted - 17 Feb 2014 :  10:30:52 Show Profile Visit Mr Burrrrrrrrrrt's Homepage Reply with Quote
quote:
Originally posted by pchristy
I think you'll find that those hoses connected to the auto-choke are hot water hoses. The auto-choke detects from the water temp when to turn off. Its a long time since I replaced an auto-choke, so others will correct me if I'm wrong, but I think you need to join the two hoses together with a bit of pipe and some jubilee clips.




This is correct.
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Derek
V4 Guru

United Kingdom
1778 Posts

Posted - 17 Feb 2014 :  12:56:34 Show Profile Reply with Quote
But, if you want to change to a manual choke you'll need the manual bits for the carb I think. I've got 3, wrongly purchased, 34ICH carbs, 2 x 29 and 1 x 25. None of these have auto chokes and the 27 that went to Oz with my 96 didn't either . Dare I suggest that you've been sent the wrong carb? You need one with a basic manual choke mechanism. A cable and brackets would come with the kit even if you don't want them. Worth checking before you start messing about with it.
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tommygoldy
V4 Fan

142 Posts

Posted - 17 Feb 2014 :  20:38:08 Show Profile Reply with Quote
quote:
Originally posted by Derek
But, if you want to change to a manual choke you'll need the manual bits for the carb I think. I've got 3, wrongly purchased, 34ICH carbs, 2 x 29 and 1 x 25. None of these have auto chokes and the 27 that went to Oz with my 96 didn't either . Dare I suggest that you've been sent the wrong carb? You need one with a basic manual choke mechanism. A cable and brackets would come with the kit even if you don't want them. Worth checking before you start messing about with it.



The carb has clamps/brackets for the choke cable (and linkage to the throttle for cold start) and there's an old choke cable in the car already. Unless I'm missing something I should be good to go.
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Andyinthegarage
V4 Fanatic

United Kingdom
357 Posts

Posted - 19 Feb 2014 :  23:19:33 Show Profile Reply with Quote
OK, there is loads of great advice out there (and in this post) which I have gratefully used myself, but I tried to tie it all together to give my own experiences and at the same time give a step by step guide to setting up the Weber34 ich - I include it for what it is worth and tho I don't imagine it is the only way...it is One way - hope someone finds it useful - sorry it is rather long:

The Weber 34 ICH is a common direct replacement for FoMoCo carbs, is relatively easy to connect to the throttle linkage, and bar a few pinch points against the servo-vacuum pipe, drops straight in. When correctly adjusted it will give better fuel economy and increased power particularly when combined with an improved exhaust system but if you dive into adjusting stuff without a plan, you can be chasing your tail with no benefits.
So….before you attempt any adjustment:
Make sure your carb has the magic “27” size venture as stamped on the casing – it isn’t impossible to set up a different carb, but 25 won’t give you best performance and 29 is very difficult to get right with most un-tuned engines.
Make sure that your in-line fuel filter is clean, you have adequate clean fuel in the tank and that all electrics are in good order.
Check that the carb is in good condition with the internal filter recently cleaned or replaced. Ideally give it a full service.
Set the timing to standard 6 degrees, and if possible, pre-warm the engine to make starting easier – not hot, just warmed.
After changing anything, replace the air filter before final adjustment of tickover and fuel mix as the type of filter will slightly affect things.
Keep your tools clean to avoid adding dirt to the confusion!
Start settings:
Most agree the standard settings for a 1.5 as being close to those listed below but individual engines, carbs, filters, fuel, altitude, opened manifold passages, exhaust choice etc will all make tuning worthwhile. So, I set up as follows:

Main 155
Idle 55
Emulsion Tube F6
Air Corrector 175
Pump Jet 40

Now, the fun begins….

Start with the idle circuit which takes care of 80% of the performance improvement available and whose fuel is controlled by the Idle Valve.

Back off the tickover adjustment until the screw no longer touches and the throttle plate is closed. Slowly adjust it back until it just touches – watch very closely (smoker's trick is to slip a leaf of hand rolling paper between the surfaces to check clearance)…and then count it in ONE AND A HALF TURNS more. Don’t go beyond this as the throttle plate will clear some very small apertures inside the body and start using a different cycle.
Screw in the mixture screw until it GENTLY grounds and then back out 2 full turns.
Start the engine – it should run, but may sound quite rough, certainly very slow but as long as it is running and not “hunting” it is fine.
If it won’t start, close the throttle tickover screw half a turn just to get it started and remember to open it the same amount once it is running.
Now, by ear, adjust the mixture screw a quarter turn at a time until you find the sweet spot right in the middle between the point where it stops increasing the revs, and the point when it starts to sound a little rough.
Once you have found the best setting, turn off the engine and turn the mixture screw in until it gently grounds again. As you do this, count the turns as this will indicate if you have the right idle valve. Opinions vary (as do engines) but if the sweet spot is between 1 ½ to 2 turns then it is pretty much there. You could try a different idle valve just to see what changes, but otherwise you are fine.
If you count less than 1 ½ then your idle circuit is drawing too much fuel. This is very unusual, so check that your tickover is at 1 ½ turns and repeat the mixture screw adjustment. If you get the same result try a “50” idle valve, but if this doesn’t correct the setting it is unlikely to improve by going further. So strip and clean the carb.
If you count more than 2 turns, you need more fuel in the idle mixture. Go up a size in idle valve (increments of 5). Most engines seem happy in the range 55 – 65.

Repeat your idle mixture screw testing until you are happy, then adjust the tickover to about 850 - 900 rpm with a decent electrical load such as main beam. Replace your air filter, check the settings are unchanged and move on to testing the next circuit and so setting the Main Jet.

Unless you have access to a rolling road, the best test is for the “Kill” method – sounds dramatic. You will need a good long hill, steep enough for you to hold about 1/2 to 3/4 throttle without taking off, with safe places to pull over, no traffic and a spark plug spanner. (That's you, not the hill). Engage free wheel (makes stopping easier). With a warm engine, and fresh or at least clean plugs, set off up the hill on a steady ¾ throttle. After at least half a mile and assuming it is safe to do so, kill the ignition without first changing the throttle, and coast to a halt dropping the car out of gear and releasing the throttle once the engine is dead.
Take out at least two plugs from opposite sides and examine. Oily plugs suggest that the main valve is too big and vice versa for hot dry plugs. Adjust and try again. Again, engines vary, but I have seen preference range from 155 – 185 for a 1.5 engine.

Finally recheck timing hasn’t wandered.

Hopefully by now you have a fairly good setting which you can then gently tweak to get the best average setting for all temperature, load and altitude conditions.

You can also try advancing the ignition a little, but only change one thing at a time!.......Have fun!

Edited by - Andyinthegarage on 20 Feb 2014 18:57:57
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john-saab
Administrator

United Kingdom
2647 Posts

Posted - 20 Feb 2014 :  07:16:46 Show Profile Reply with Quote
Well done Andy..great advice.

'72 95 (The Flying Banana),'72 96(Bridget),'72 96 (green one)'73 96 (Vernon),'74 95 (Veronica)
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tommygoldy
V4 Fan

142 Posts

Posted - 21 Feb 2014 :  21:24:15 Show Profile Reply with Quote
quote:
Originally posted by john-saab
Well done Andy..great advice.


Agreed! Thanks!
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john-saab
Administrator

United Kingdom
2647 Posts

Posted - 17 Apr 2014 :  20:25:31 Show Profile Reply with Quote
Yet again a Weber 34ICH has transformed a V4. My latest Verona 96 has been horrible to start, horrible to drive and a gutless experience. I fitted a ICH today and this car is now superb to drive, easy to start and FUN FUN FUN!..a HUGE difference.
quote:
Originally posted by Andyinthegarage


Back off the tickover adjustment until the screw no longer touches and the throttle plate is closed. Slowly adjust it back until it just touches – watch very closely (smoker's trick is to slip a leaf of hand rolling paper between the surfaces to check clearance)…and then count it in ONE AND A HALF TURNS more. Don’t go beyond this as the throttle plate will clear some very small apertures inside the body and start using a different cycle.

At this point look down into the throttle body..if you can see fuel dripping onto the butterfly then you know you have an issue. The fuel should be vapoor at this stage.


'72 95 (The Flying Banana),'72 96(Bridget),'72 96 (green one)'73 96 (Vernon),'74 95 (Veronica)
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Zagato
V4 Mad

United Kingdom
740 Posts

Posted - 19 Apr 2014 :  07:54:09 Show Profile Reply with Quote
Although my Fomoco starts, runs and ticks over nicely and I have never had a problem with them I seem to encounter more advice about getting it swapped for a Webber as it's a much better carb. Coming from a Land Rover environment the advise is 50/50 on this. They can be troublesome and can freeze in the winter - maybe this is just for Landies. The original Solex carb once refurbished is advised by many(Zeniths are rubbish!). Well known advice is also to check any new carb bought doesn't come from China cos it won't work, better to get your old carb refurbished by 'carburetor exchange'. I wonder where these new Webbers are made!!!

A recent warning was that the Fomoco can mess up your engine if the old rubber parts have deteriorated (not sure exactly what was meant)but something to do with petrol just pouring in which can be seen if you take the air filter off.

If I do the conversion is there anyway or retaining the original black plastic air filter casing or do I have to put on the silly little chrome thing? I've got a feeling there is an issue on later models as the fixing point onto the rocker cover is on a different side!! I think I have seen some later cars with Webbers but they have had to put on an early type air filter which doesn't look right to me.

1977 96L Opal Green

Edited by - Zagato on 19 Apr 2014 07:56:19
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