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Mon Nov 17, 2008 3:14 pm

I've just acquired a bus with an old 1700. I have a few issues(and so does the bus). the bus does not accelerate smoothly off the line or while underway.The issues are: 1-it has a 2 bbl progressive carb and a 009 dist. And I was told it is the original motor. When at idle it backfires"pop-poop-pif" The dist # is0231178009 is this the correct one for the motor? Is the carb tuned wrong? Do I have a dropped valve seat or two. I know the 009 is a bad dist. I'm just trying to get this thing to limp along while getting my s--t together for a new motor. Thanks for any advice.

Mon Nov 17, 2008 3:31 pm

Sounds like the typical poor type 4 bus engine that has had some idiot previous owner take off the stock twin soles carbs and stock distributor with vac, and fit incorrectly jetted badly tuned single carb and a shitty 009.

You wont have much fun trying to get it to rub great, first time the 009 http://www.vw-resource.com/009_dizzy.html

Check for any inlet or exhaust vacuum leaks.

Center mount carb I cant help you with. :cry:

Mon Nov 17, 2008 3:37 pm

babysnakes wrote: I've just acquired a bus with an old 1700. I have a few issues(and so does the bus). the bus does not accelerate smoothly off the line or while underway.The issues are: 1-it has a 2 bbl progressive carb and a 009 dist. And I was told it is the original motor. When at idle it backfires"pop-poop-pif" The dist # is0231178009 is this the correct one for the motor? Is the carb tuned wrong? Do I have a dropped valve seat or two. I know the 009 is a bad dist. I'm just trying to get this thing to limp along while getting my s--t together for a new motor. Thanks for any advice.

Your problem is probably mostly in that carburetor. It was not designed for the aircooled engine. See those long, unheated runners going to the cylinders? The carb is not really matched for the vacuum pull into those. It's rare to find a progressive carb that is set up to run properly on such an engine. It can be done, but it often requires a lot of work and trying of a lot of different jets, plus insulating/heating the manifold runners. There's been many topics where people talk good and bad about the progressive (me, usually bad) - here's just one of them:

http://www.thesamba.com/vw/forum/viewtopic.php?t=180520&

From the Factory, that engine had dual carbs, kind of a crappy design though. When it wore out the cheapest replacement option was the progressive, so that's probably why that thing is on there. If it was my Bus, I'd lose that thing and get some aftermarket dual carbs. The 009 distributor - with the carb you have that's your main option, unfortunately. Some are better than others. Old German made ones can be decent. Newer Brazil ones, and especially Chinese made clones, can suck.

If you suspect bad valves or low compression - you need to do a valve adjustment (sinking/eroding valve seats or stretched valves should be obvious comparing valve stem height) and then a compression test.

I'd verify the advance is working with a timing light and then set the timign properly. And check that the accelerator pump setup in the carb is spraying when the throttle is opening. Some tweaking the idle mixture may help out too.

-Andy

Mon Nov 17, 2008 4:08 pm

Well both of you seem to confirm my thoughts. I read all the opinions on the 009 nothing but ragging but no one suggested a good alternative. I have a pair of both 40 dcnf and 34 ict I kept from the years ago, before I got out of the hobby. Which would you recommend?

Mon Nov 17, 2008 4:09 pm

Well both of you seem to confirm my thoughts. I read all the opinions on the 009 nothing but ragging but no one suggested a good alternative. I have a pair of both 40 dcnf and 34 ict I kept from the years ago, before I got out of the hobby. Which would you recommend?

Mon Nov 17, 2008 4:12 pm

BTW I also checked the valves they were good (.006 intake,.008 exhaust).The timing when I got it was set 6 deg ATDC instead of 4deg BTDC. It ran better before I adjusted the timing

Mon Nov 17, 2008 7:47 pm

I'd check the total advance - you can go to 32 total on a type 4 engine. That would probably put you to around 12BTDC static, IF the distributor is working right.

The stock carbs were dual 34s, so a pair of dual 34 aftermarket ones would work. The 40s would work too. It's not a huge engine though, only 1679cc. So the smaller ones should be OK. Jetting, of course, would need to be done. I think I'd pick out the ones in the best shape.

Tue Nov 18, 2008 3:07 am

babysnakes wrote: Well both of you seem to confirm my thoughts. I read all the opinions on the 009 nothing but ragging but no one suggested a good alternative. I have a pair of both 40 dcnf and 34 ict I kept from the years ago, before I got out of the hobby. Which would you recommend?

For an easy life sell both of those carb sets, and buy stock 1700 type 4 carbs and a stock distributor, then you can just use factory timing and manual to tune it.

Wed Nov 19, 2008 7:11 pm

Jeeze,if I wanted an EZ life I'd just stick w/my 1985 Silverado. Its hard to find parts at a good price in Fla. I just did a compression test, all 4 cylinders were from 148-156 psi.(not bad). It still backfires and I'll put that to exhaust leaks.I can seal the tail pipe w/my hand and the motor still runs. I have the carbs I said and a good handful of extra jets for the 40's. So based on the compression,I will move forward.

Thu Nov 20, 2008 6:28 am

So I dont want to sell my carb because I still have a good built t-1 short block I may use in the future. My new question is, my 34ICTs have a pressure equalizer tube connecting both intake manifolds. can I put an inline tee and use that for the vacuum advance for the distributor?

Thu Nov 20, 2008 6:53 am

babysnakes wrote: So I dont want to sell my carb because I still have a good built t-1 short block I may use in the future. My new question is, my 34ICTs have a pressure equalizer tube connecting both intake manifolds. can I put an inline tee and use that for the vacuum advance for the distributor?

No this is not a correct vacuum signal for a distributor.

You need to attach the vac pipe to the correct take off port on the carb body.

Thu Nov 20, 2008 8:15 am

Saying a Weber Progessive was not designed for a bus is a backwards as saying a Holley Carb should not used on a 67 327 Chevy cause they came with Rochesters. Since a carb is a carb it is a matter of proper tuning that makes them work.

Your initial idle setting is not correct, to start, possible the throttle plate is not open enough because the idle jets are too big, or open too much cause the jets are too small. Verify the pump jet is squirting as the throttle is opening. This is where the stumble begins and not neccessaily because of a 009. Your mains may be too big or too small.

Record all the jets for both the primary and secondary along with which emulsion tubes the carb has. You got to know what you have before the problem can be fixed.

Report back with those numbers.

Thu Nov 20, 2008 8:37 am

I've always heard nothing but complaints about this carb. HOWEVER; I like to respect other trains of thought. So "busman78" I will examine the carb, take it off and find as much info as I can. I will report back this afternoon,or tomarrow a.m. I am far from knowledgeable about carbs. I have rebuilt many,but never modifiying jets. The 40dcnf's I have came with a box of jets and I'm just as ignorant now as I was 15 years ago when I got them. Thank you for your push in the right direction.

Thu Nov 20, 2008 8:59 am

Its always the carb that gets blamed, but that is not the fault, i think its already been said in this thread but the problem is in the very long unheated inlet manifold.
The fuel has trouble staying vaporized and in suspension in this cold long runner and fall out and puddles, droplets of fuel don't burn like vaporized fuel, it just get fried and then spat out the exhaust.

You can tune the carb to make the best of this, but it wont be as good as a stock twin carb set up and have worse mpg.

Thu Nov 20, 2008 10:27 am

you also have poor engine response with sutch long runners ive worked on driven and have riden in type 4s with a single progresive that were set up right and ran very well but if you want your bus to run like it should id make the strp over to dual carbs

Thu Nov 20, 2008 12:09 pm

Ok Ok, I have read most of what has been recommended as far as a dual setup is concerned. It will still require some funds to be spent. Right now I can barely drive around the block, so if I can better tune this progressive it will buy me some time. I ran the 34ICTs on a 1835'1600 and on a high compression 1600 I ran in the 1/4. So I don't need to be convinced they are a better choice. I'm just struggling like so many others, Besides I've never messed w/jetting so the edjamakashun will be welcome. I'll keep posted to let ya'll know how it goes. Thanks for the help

Thu Nov 20, 2008 2:06 pm

Since Babysnakes is in SoFla I doubt cold runners will be a problem, in fact they really are not a problem till you get below thirty, sometimes even colder depending on the humidity.

Here is a neat thread to read over on the Baywindow Froum
http://www.thesamba.com/vw/forum/viewtopic.php?t=217070&highlight=weber

On Redline Weber site they have the instructions for setting the Best Lean Idle which is uno #1 thing to do, if the idle is not right then no other changes will be effective.

I will be out of pocket starting tomorrow morning before the sun rises, delivering a Fastback to Phoenix, but post the numbers and if nobody responds I will when I get back Saturday.

Thu Nov 20, 2008 5:22 pm

Well so far I got the carb off just before dark. I let the fuel pump top off the resevior. I activated the throttle 4-5 times it dribbled until about 1/2 throttle then it squirted. It is a Weber 32/36 DFAV. I down loaded the schematic and will be pulling the jets in the A.M.

Thu Nov 20, 2008 6:09 pm

Accel pump is worn, it should squirt from the start.

Fri Nov 21, 2008 7:14 am

Ok, that's a good start. I'll replace that 1st. Don't know if I can get 1 today.