34 PICT 3 adjusting

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Sylvester
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34 PICT 3 adjusting

Post by Sylvester » Fri Jul 13, 2012 6:25 am

Last month when Colin visited, we looked into my Bus not wanting to idle. Upon taking the carburetor apart and back in, we determined the RTV holding the pilot jet to it's location had come loose and plugged the pilot jet. The RTV was holding the screw in place, it is not screwed completely into the carburetor. Colin adjusted the pilot screw after we cleaned it out, and viola I had idle. Since then, I am back to no idle. 98% of the time, when I am driving and let off the gas, Samantha will die. I adjusted the pilot jet out a few turns while running on Tuesday and it helped the idle, until the next day I was back to dead at any stop. So I ask this, can I swap pilot jets from my spare 34 PICT 3 and see if that is the issue?
Up, up the long, delirious, burning blue, I’ve topped the wind-swept heights with easy grace. Where never lark, or even eagle flew. And, while with silent, lifting mind I've trod, The high untrespassed sanctity of space, Put out my hand, and touched the face of God.

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RSorak 71Westy
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Re: 34 PICT 3 adjusting

Post by RSorak 71Westy » Fri Jul 13, 2012 8:19 am

You talking about the idle jet that screws into the passenger side of the carb right? If so try 1st removing yours and poking a fine wire thru the bottom hole and making sure its clear and reinstall it.
Take care,
Rick
Stock 1600 w/dual Solex 34's and header. mildly ported heads and EMPI elephant's feet. SVDA W/pertronix. 73 Thing has been sold. BTW I am a pro wrench have been fixing cars for living for over 30 yrs.

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Sylvester
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Re: 34 PICT 3 adjusting

Post by Sylvester » Fri Jul 13, 2012 8:25 am

RSorak 71Westy wrote:You talking about the idle jet that screws into the passenger side of the carb right? If so try 1st removing yours and poking a fine wire thru the bottom hole and making sure its clear and reinstall it.
Yes, number 34 here in the diagram:

Image

We used a pint to clear it last month and it does make sense it is plugged again. I will give it a shot today and see if it helps.
Up, up the long, delirious, burning blue, I’ve topped the wind-swept heights with easy grace. Where never lark, or even eagle flew. And, while with silent, lifting mind I've trod, The high untrespassed sanctity of space, Put out my hand, and touched the face of God.

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sped372
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Re: 34 PICT 3 adjusting

Post by sped372 » Fri Jul 13, 2012 8:40 am

Here's a very good (albeit lengthy) thread on the oTher Site about the 34-3. It's worth reading through the entire thing if you have the time.

http://www.thesamba.com/vw/forum/viewto ... &start=100

I've read that if the jet gets overtightened it can cause problems because it doesn't seat correctly any more.
1971 Karmann Ghia - 1600 DP
1984 Westfalia - 1.9 WBX

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Amskeptic
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Re: 34 PICT 3 adjusting

Post by Amskeptic » Fri Jul 13, 2012 10:44 am

Sylvester wrote:Last month when Colin visited, we looked into my Bus not wanting to idle. Upon taking the carburetor apart and back in, we determined the RTV holding the pilot jet to it's location had come loose and plugged the pilot jet. The RTV was holding the screw in place, it is not screwed completely into the carburetor. Colin adjusted the pilot screw after we cleaned it out, and viola I had idle. Since then, I am back to no idle. 98% of the time, when I am driving and let off the gas, Samantha will die. I adjusted the pilot jet out a few turns while running on Tuesday and it helped the idle, until the next day I was back to dead at any stop. So I ask this, can I swap pilot jets from my spare 34 PICT 3 and see if that is the issue?
Clean it. Again.
If you have to, clean it again and again as symptom crops up.
Always check your dwell first, as closed point gap can mirror carburetor symptoms.

Do NOT go on a goose chase . . . yet.
Keep it simple.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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Sylvester
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Re: 34 PICT 3 adjusting

Post by Sylvester » Tue Jul 31, 2012 2:26 pm

The funny part of this scenario is, I can't keep the bus idling long enough to check the dwell! In a small fury I pulled my point out and installed my Pertonix I had on the shelf. When I went to check the point gap, after just setting it and checking dwell not too long ago, I found the points just barely closing and the gap way too close. On top of the pilot jet issue Sam ran like crap. Finding the points way off was the last straw for them. I still have the pilot jet issue but Sam runs so much nicer. My second act will be to swap carburetors and see if that makes a difference. Now no matter where I adjust the pilot jet, it does not idle at all.
Up, up the long, delirious, burning blue, I’ve topped the wind-swept heights with easy grace. Where never lark, or even eagle flew. And, while with silent, lifting mind I've trod, The high untrespassed sanctity of space, Put out my hand, and touched the face of God.

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sped372
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Re: 34 PICT 3 adjusting

Post by sped372 » Tue Jul 31, 2012 2:32 pm

Sylvester wrote:Now no matter where I adjust the pilot jet, it does not idle at all.
Wait, what? Adjust the pilot jet? I must be missing something, there's no adjustment there.
1971 Karmann Ghia - 1600 DP
1984 Westfalia - 1.9 WBX

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Sylvester
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Re: 34 PICT 3 adjusting

Post by Sylvester » Tue Jul 31, 2012 4:53 pm

sped372 wrote:
Sylvester wrote:Now no matter where I adjust the pilot jet, it does not idle at all.
Wait, what? Adjust the pilot jet? I must be missing something, there's no adjustment there.
Sylvester does not speak in riddles. When I replace my crappy Weber with the Solec that came in a box in Sam, it would not idle until we unscrewed the pilot jet and held it in place with some organ RTV that eventually broe up and plugged the jet. Since then despite many cleanings, one replacement and more adjusting, it has never idled correctly. Reading that article on the Samba explained how that can happen.
Up, up the long, delirious, burning blue, I’ve topped the wind-swept heights with easy grace. Where never lark, or even eagle flew. And, while with silent, lifting mind I've trod, The high untrespassed sanctity of space, Put out my hand, and touched the face of God.

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sped372
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Re: 34 PICT 3 adjusting

Post by sped372 » Wed Aug 01, 2012 5:46 am

Ok, I see. Not an adjustment, per se, but fiddling. What's your "spare" carb situation?
1971 Karmann Ghia - 1600 DP
1984 Westfalia - 1.9 WBX

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Sylvester
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Re: 34 PICT 3 adjusting

Post by Sylvester » Thu Aug 02, 2012 3:26 am

sped372 wrote:Ok, I see. Not an adjustment, per se, but fiddling. What's your "spare" carb situation?
I have a German spare I pulled from a Ghia in the pick a part a few years back. I cleaned it up and will see how it works this Friday. On a side note I met a fellow who lives near me who has a 73 Bus and Bug. He is giving me the 34 off the Bug, hopefully it does not have pilot jet fatigue.
Up, up the long, delirious, burning blue, I’ve topped the wind-swept heights with easy grace. Where never lark, or even eagle flew. And, while with silent, lifting mind I've trod, The high untrespassed sanctity of space, Put out my hand, and touched the face of God.

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Amskeptic
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Re: 34 PICT 3 adjusting

Post by Amskeptic » Thu Aug 02, 2012 9:10 am

Sylvester wrote:hopefully it does not have pilot jet fatigue.
... unlike those F-22 guys with oxygen deprivation.
You *can* compensate for a torn up opening where people have mashed it and stripped threads and whatnot, if you can see in there well enough to determine if the hole directly staring back at you is still round and does not have a crater wall where material was displaced into the actual jet opening. a tiny tiny drill bit hand twirled may clean it up if your issue is leanness, which I think it was when we were there. This all, by the way, is predicated upon correct float levels cleanliness, correct accelerator pump discharge, etc.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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Sylvester
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Re: 34 PICT 3 adjusting

Post by Sylvester » Fri Aug 03, 2012 5:36 am

Amskeptic wrote:
Sylvester wrote:hopefully it does not have pilot jet fatigue.
... unlike those F-22 guys with oxygen deprivation.
You *can* compensate for a torn up opening where people have mashed it and stripped threads and whatnot, if you can see in there well enough to determine if the hole directly staring back at you is still round and does not have a crater wall where material was displaced into the actual jet opening. a tiny tiny drill bit hand twirled may clean it up if your issue is leanness, which I think it was when we were there. This all, by the way, is predicated upon correct float levels cleanliness, correct accelerator pump discharge, etc.
Colin
I will give it a twirl before I replace it tonight. I will report the Pertronix is doing well, no more hesitation on take off. I have so much to do to Samantha, this past year has seen a lot of camping and usage of the old girl.
Up, up the long, delirious, burning blue, I’ve topped the wind-swept heights with easy grace. Where never lark, or even eagle flew. And, while with silent, lifting mind I've trod, The high untrespassed sanctity of space, Put out my hand, and touched the face of God.

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Sylvester
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Re: 34 PICT 3 adjusting

Post by Sylvester » Mon Aug 13, 2012 5:58 am

As an update I was not able to change the carb so quick, I had my boys this week so I stretched it out a few days. Bad choice. Thursday I am adjusting the pilot jet some to get Sam to idle. Friday afternoon in traffic the Bus dies and avoiding a rear ending from a large SUV, I pull over (Well, floated over) to the side of the road, avoid the four lane traffic screaming past me, and by the way honking at me does not make me move further off the side, whomever thought they were "helping" me, and go to the engine compartment. A quick look shows the pilot jet is gone, it worked it's way out while driving. So I begin the search and find it laying on the block behind the fuel pump. With ginger fingers I pull it out, screw it in with a leather-man (Took the tools out earlier and spare parts, watch where this goes later) and fired up and away we went. So I am still stuck with no idle.

I planned on swapping carbs after Guard this weekend on Sunday, but fate stepped in to lend a hand. Here is a lesson about fate.

On the way home from Guard I am 20 miles out, the Bus dies at the worst possible place, on a eight lane highway and I am on the far left side trying to merge into traffic when it happens. I coast (Well, float again) to the far left side. Cars honking and passing at 70MPH just inches from my passenger side, pilot jet is still there and tight. One thing I noted before I lost power, the tachometer jumped all over the place while it died. I look at my connections from my new Pertronix set up, I figured a short but I see nothing to indicate wires were in crossed, a terminal touched, anything. I call the roadside assistance, that takes thirty minutes. Since I am not at an address, they have no idea where I am and how to price this. Uh huh. I go back to the engine, and look at the trees and not the forest this time. My coil has slid down a but from it's holder, it is lower than it should be. Using my leather man again (Remember I took out the tools and spare parts), I adjust it back up and straighten out the wires to it. Sam fires right up, and I am off heading home. 20 miles later, on the off ramp Sam starts to struggle again. This time it dies in the middle of a four lane road, really in the right lane, it was up hill and I could not pull over. So in the middle of the road I discover the coil has slid down again, a leather man can only do so much. I adjust it again, let it cool off, and limp home. Karma says I should have gotten rid of that damn chrome sleeve long ago, as seen in this picture. Why it picked this day to slide down is a mystery to me.

Image

At home, I ditch that sleeve and put the coil in a stock holder. That was a PO thing, I am not a chrome lover. I clean up the wires from the Pertronix, I had to cut the original wires because the connectors would not fit through my SVDA port. I take off the 34 Pict 3 that came with Sam in a box when I bought her. Colin and I had put it in there two years ago. I figured it was the original, and I had rebuilt it before I put it in. It had an issue with the pilot jet from day one. In it's place I had a carb I pulled from a Ghia in a junkyard in 2010. I had cleaned it out but not rebuilt it. I placed it on Sam, connected it up, and tried to start it.

No start.

I can't smell any gas coming from the carb. I take it off and check the bowl. No gas. I check the float valve (SEE ABOVE DIAGRAM PART #5), it was sticking. So I take the one from the carb I just removed, that part was working fine. I screw it all back together and put it on Sam. I go to the front and crank it, hoping the bowl is filling up.

It starts.

And it runs. I gingerly take my foot off the gas pedal.

It idles.

I hear angels sing, the plants and animals near me join in and smile. The sun would have just then come from behind a cloud and shone on me, but it was 9:00PM and dark, and besides the back of Sam was in the garage. Even though it it idling high and is running rich, I let it run for awhile, just to hear it. I have been fighting this battle for awhile. I want to finish it but I am so tired I can't think. I shut it off and head inside, I will finish it tonight and post the results.

BTW Colin, I did try this with the drill bit but it was no luck. I think this may have been why this carburetor was in a box when I bought Sam, and the Weber 2 barrel was there in it's place.
Amskeptic wrote:
Sylvester wrote:hopefully it does not have pilot jet fatigue.
... unlike those F-22 guys with oxygen deprivation.
You *can* compensate for a torn up opening where people have mashed it and stripped threads and whatnot, if you can see in there well enough to determine if the hole directly staring back at you is still round and does not have a crater wall where material was displaced into the actual jet opening. a tiny tiny drill bit hand twirled may clean it up if your issue is leanness, which I think it was when we were there. This all, by the way, is predicated upon correct float levels cleanliness, correct accelerator pump discharge, etc.
Colin
Up, up the long, delirious, burning blue, I’ve topped the wind-swept heights with easy grace. Where never lark, or even eagle flew. And, while with silent, lifting mind I've trod, The high untrespassed sanctity of space, Put out my hand, and touched the face of God.

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Sylvester
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Re: 34 PICT 3 adjusting

Post by Sylvester » Mon Aug 13, 2012 6:32 pm

I adjusted the carburetor today as best as I knew how, not sure I am any good but I still have it idling high, a couple of times at a stop it would want to die, so I adjusted the Bypass screw and the Volume control screw. If I can get these right, this thing will purr like a cat. It still idles at 1600 but I am wary to adjust it any lower to where it will die at a stop. This is what I followed:

If you have a single-vacuum dual advance (SVDA) distributor, remove the vacuum hose from the distributor and plug it to prevent air from being sucked into the carburetor. Also remove and plug the vacuum hose to the aircleaner to prevent air from being sucked into the intake manifold. (Regarding removal of the vacuum hose, see the following note.

Note: If you have a single vacuum distributor, when you adjust the timing later you will remove the vacuum line from the vacuum canister on the distributor and plug it to prevent air from entering the carburetor. When you set the idle speed, it shouldn't make any difference whether the vacuum line is removed or not, since at the lower idle speed the airflow through the main throat is very small. But if the idle speed is up a little the vacuum line WILL see a vacuum signal, and this will affect the advance. So the safe bet is to remove and plug the vacuum line and set the idle speed with it off - that way you are sure that you are only dealing with the centrifugal advance. The vacuum advance does not begin to work until about 1200 rpm (so it shouldn't affect the idle speed at all of course).

Start the engine and run it for at least five minutes to warm up.

Allow the engine to idle. Remove the aircleaner and make sure that the automatic choke is fully open (it's the butterfly valve in the top of the carburetor -- with the engine warm the valve should be standing straight up) and the stepped throttle (fast idle) cam on the left side of the carburetor is all the way up so that the screw on the top of the throttle arm is resting on the lowest point on the cam.

Note: The idle is set with a "Volume Control" screw and a "Bypass" screw of the left side of the carburetor. The Volume Control screw is the lower one and is the smaller of the two. Both are recessed into the carburetor and must be accessed from the side with a screwdriver. The Bypass screw (the larger one) is used to adjust the idle speed. The Volume screw is the idle mixture setting.

Note the rpm on the tachometer; you will adjust it to 850 - 900 rpm (the specification given in the book) as follows:

Adjust the screw on the top of throttle lever so that it just touches the fast idle cam. Then turn it in 1/4 turn.

Note: This step is very important. It opens the throttle butterfly in the carburetor 0.004" so that the idle jet will work properly.

Also Note: In the exploded view of the carburetor, this screw is called the "Idle Control screw." This is misleading, as this screw is NOT used to set the idle as it was on earlier carburetors. The Volume Control and Bypass screws on the left side of the carburetor are used to set the idle speed.

Turn off the engine momentarily.

Slowly turn in the Volume Control screw until it bottoms lightly. Then back it out 2-1/2 to 3 turns. This is the starting point for this screw.

Note: The Bentley Manual says, "Do not adjust the mixture by turning the Volume Control screw unless (1)you have installed a different carburetor, (2) you have removed, repaired, or rebuilt the carburetor, or (3) the engine is producting excessive emissions." This adjustment is critical - use a flashlight and make sure you have a good line of sight. The Volume Control screw out of whack can cause exasperating performance problems.

Restart the engine and adjust the Bypass Screw until you obtain the desired idle speed (850 - 900 rpm) as indicated on the dwell-tachometer. Turning the bypass screw out increases the rpm; turning it in decreases the rpm.

Turn the Volume Control screw one way or the other to obtain the highest idle speed, then turn the screw clockwise (in) until the engine speed drops by about 25 rpm.

Note: This step is a little tough--it's hard to see a 25 rpm difference on the tachometer, especially if you're using a tachometer designed for an 8-cylinder car. Do the best you can.

Reset the idle to 850 - 900 rpm using the Bypass Screw.
Up, up the long, delirious, burning blue, I’ve topped the wind-swept heights with easy grace. Where never lark, or even eagle flew. And, while with silent, lifting mind I've trod, The high untrespassed sanctity of space, Put out my hand, and touched the face of God.

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Amskeptic
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Re: 34 PICT 3 adjusting

Post by Amskeptic » Fri Aug 24, 2012 6:42 am

Sylvester wrote: Adjust the screw on the top of throttle lever so that it just touches the fast idle cam.
Then turn it in 1/4 turn.
Note: This step is very important. It opens the throttle butterfly in the carburetor 0.004" so that the idle jet will work properly.
That would be true for the PDSIT dual carb buses.
The 34Pict3 I believe, needs a .020-.040 gap between the screw and the fast idle cam?
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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