1915 with dual 40IDFs running way to rich

[bastardbus]

Hi guys, I came across this car locally for an absolute screaming deal but she has issues. I have been heavily into VWs since 87 but ALWAYS been a 100% stock guy, so looking for just little advice tips on this one. Here is details.

Nice car, clean orig metal `71 restore call look ish, Previous owner bought the long block from Chico Performance 1915, new AS41 case, full flowed, seem to be stock heads and guessing cam too from what I can tell. The PO owner said he just oreder the 1915 with nothing fancy. So no info as far as what the cam and compression might be. My guess stock or Engle 100 at most?

The PO then added the externals including the Dual Weber 40IDFs (Spain built). He said he had nothing but problems with the car running rich. Would foul the plugs (W8AC Bosch looks like) in a very short period, sometimes just hitting the throttle hard once would kill the plugs. Took it to two different local shops and they had no luck. He was moving and fed up with dealing with the car and sold it to me for a song...seriously.

So pulled the carbs last night, they don't look "new" to the car. They seem used and fairly dirty but in decent shape. I checked jetting and it looks to be what these came with stock. Venturis are 28mm/ 200 air/115 main/50 idle/F11 emulsion.

A couple issues I noticed..the fuel pump is a square faucet style that clicks loudly, did not check it up close for model yet and I see no pressure regulator. I have read these webers are very fussy about proper PSI and flow. The accelerator pump adjustment seems to be cranked down pretty far and they really seemed to be putting out a LOT of squirt. Not sure what a norm setting would be on these but seems this could be huge issue as well.

I was pondering if I should buy factory rebuild kits and go through these or just buy a new set and go from there. I am very confident in my skills but the 40IDFs are something new to me. Any tips suggestions or things to check for wear on these used carbs I have before I go further is appreciated.

_________________
Samba Member #95

[74 Thing]

Take the carbs apart and clean with carb cleaner and compressed air then re-assemble and set the float levels. Verify that the jet sizes are correct as well (you may have to buy jet gauges).

Then get yourself a vacuum/pressure gauge for approx. $20 at your local car parts store or online and tee it in and verify fuel pressure at the carbs-should be around 3psi.

I do not see the photo of the faucet pump in the engine bay.

CB Performance sells a Carter rotary pump that you install under the fuel tank and puts out around 3psi.

[FritzCP]

check/ rest set the floats to spec.
_________________
Fritz Custom Products
Fritz 10 - Tin Screw Torquer
Fritz 124 - Crank Pulley Puller
Fritz 70 - 6306 Bearing Puller
Fritz 44 - Dizzy Puller

[bastardbus]

Faucet pump is under the tank up front. I did read up on the rotary Carter online and planned on that. Was going to check the PSI tonight as well.

Yes I pondered the jet gauges, any recommendations on who to purchase from?

Hey Brad, just stopped by your place a week or so ago. Closed up and beat early bay sitting outside. We were up in Hatfield for about 3 weeks but busy busy.

Cool will make sure I set the floats up right. Do the floats usually survive or do they have issues? Also curious if there was any odd wear issues to look for on these too. I had a buddy who was big into Cal Look stuff and 48IDFs and there was a couple spots that would wear and if so they were considered JUNK. Seems like these 40s don't have those issues.
_________________
Samba Member #95

[Alstrup]

Also, plugs are 90% certain too warm. Go one step colder.
Can´t I.D. ther plug wires. Check resistance in the. Must be no more than 1 K ohm. Between 0 & 350 is good.
Increase plug gap to 0,85 mm.
Check timing. With that dizzy youy should most likely be in the 12-14 idle and 30-32 @ 3000 rpm. You want a silver/copper spring advance combination for starters at least.
Check carbs thoroughly and reset floats etc. Start, test and report back.

T

[bastardbus]

Great info! The dizzy and plug wires are Pertronix but not sure of specific model. Will did read up on the dizzy some and the various combos. Will check that too! Thanks

I have always been a strictly stock guy down to date matching parts to my cars. So this performance set up is a different beast but quite interesting and something fun new to learn. I would have never been caught dead with a car like this 10 years ago...! LOL
_________________
Samba Member #95

[FritzCP]

Sorry i missed you Todd. I was likely in Sheboygan picking up an Oval and playing at the waterpark all last weekend. you picked a good hot weekend to come up, i hope the family got to go swimming, and didnt get eaten alive by the mosquitos. Yeah, there is a Bay on site now, and it stays outside not to contaminate the shed . i wanted the 1600dp out of it. the bees have moved into it. if you brought a tow bar, it could be in your garage now for meer cost of a case of beer!
_________________
Fritz Custom Products
Fritz 10 - Tin Screw Torquer
Fritz 124 - Crank Pulley Puller
Fritz 70 - 6306 Bearing Puller
Fritz 44 - Dizzy Puller

[bastardbus]

Fuel Pressure is 3.5-4 psi and fairly steady, coil is Flamethrower 3.0 ohm and wires Pertronix 8.0 Magx2. Valves were loose all adjusted loose .008+, going to do comp test tomorrow just to check things. Looks like I am going to buy some rebuild/tune up kits for these carbs and see what happens after rebuild.

Brad, I did have a tow bar with me actually and would have taken it! LOL I might be back up in a couple weeks actually if the offer stands PM me.

T
_________________
Samba Member #95

[bastardbus]

Here is one thing that caught my eye. When I yanked the carbs and removed the gaskets I noticed that the intake manifold inlets were HUGE! I snapped a pic and took measurements 48mm.

My question is did they make specific size manifolds for each size carb or did they use a ones size fits all manifold with a 48mm inlet opening ?

Wondering if this might be a part of the rich running issue. Can anyone verify?

Check out the 40mm gasket for size comparison to the other 48mm hole.

_________________
Samba Member #95

[modok]

The manifold being HUGE is ok. I've tried manifolds that are matched to the carb size several times, and the difference is barely noticeable and maybe even not as good sometimes. Other things make more difference.
What I like to do is run a 1/4 thick phenolic spacer on the manifold, which DOES match the carb size, and a gasket over that, so the gasket has something to sit on. Picture is kinda fuzzy but maybe I see a thin plastic spacer?

with 28mm vents, I'd say the usual settings are
115-120 main
180-200 air
47-50 idle
50 acc pump nozzles, 50 bypass pump valve, adjust travel for 3/16 stroke at bottom of arm.
float level about 11mm

So, if it's rich, something is ODD. Make sure the gaskets are not covering the idle air bleed jets, make sure idle and main jets are seating, check float level, inspect float needles and seats, and make sure they are tightened, gauge jets to make sure they are the size marked. Weigh floats to make sure they aren't sunk.
All that sounds like a LOT of work, but it's pretty much the same for any carburetor. EASY carburetors to work on, you only need like two tools! 6in1 screwdriver and visegrips
Rarely have I had any problems with floats or....really anything. I never even bought a rebuild kit....since all I really ever need to replace is the pump diaphragms and misc o-rings, which I can buy separate.
There are junk replacement parts out there so don't fix what isn't broke, and if it is broke, get genuine weber replacements.
I run mainly Italian units, and the spanish are not QUITE as nice, but they are usually decent.

You can get parts from aircooled.net, I get jets from ebay, the ones from Check Republic" are good, and rare odd parts Dellorto UK and alfa1750 on ebay

Faucet fuel pump SHOULD be good match, if it is a model that puts out 3-4 psi. Maybe check fuel pressure. I've run one for almost 10 years now, not a hiccup. Hopefully it's mounted in front. (pumps push better than they pull) oh wait....it's a bus, yeah.....then I guess under the tank then.

[Dale M.]

Another source for Weber parts and tech services...

http://piercemanifolds.com

Dale
_________________
“Fear The Government That Wants To Take Your Guns" - Thomas Jefferson.

"Kellison Sand Piper Roadster" For Street & Show.
"Joe Pody Sandrover" Buggy with 2180 for Autocross (Sold)
============================================================
All suggestions and advice are purely my own opinion. You are free to ignore them if you wish ...

[anthax]

[bastardbus]

I spoke with the PO today. Asked him about the carbs. He said two years ago when he bought the car and the new long block the 40IDFs and alt were the only two things on the original engine in the car he just re used. Said they have been running worse as time when on.

Thus I have no idea on the history of the carbs and going to do a full clean-service-rebuild on them. Will get them installed and yeah gonna back those ACC adjusters all the way out and check see how she runs then.

Also, can anyone recomend a good plug and heat range. I see some old W8ACs he left in a pack but I have not pulled what is in the car yet to see. Gonna go do that in a few minutes here...

T
_________________
Samba Member #95

[[email protected]]

Imo that jetting is for a 1600, and actually LEAN for a 1915. What makes you think it’s rich? If it’s definitely fouling the plugs, I’d look more into the plugs. VW did have a “stock” head that used a 3/4 reach threaded plug. I’d take a flashlight, and mirror to take a closer look at the heads. If you’re using a 1/2 inch reach W8AC plug in a head that uses a 3/4 reach plug, the tip of the plug is not even in the combustion chamber. Maybe see if you can find someone with a jet gauge to measure the jets you have. Maybe the original jets were reamed/drilled out, and not actually the size stamped on them. Like mentioned double check the float settings as well.

[bastardbus]

Took the carbs apart tonight. Noticed a couple things and had a few questions before I proceed.

1.All 4 velocity stacks are missing.

2.One of the copper washers on the bottom of a accelerator pump nozzle was missing.

3. I was not sure of the correct way to remove these two spring loaded components. Should I leave them in place or is there a special method or tool to remove them?

4. Checking a diagram I noticed there is bearings on the throttle plate shafts. Are these sealed? Should I remove the shafts-bearings etc. I was going to soak the carbs over night but not sure if that might damage the sealed bearings. I can clean them by hand in the parts machine and with spray cleaner if need be.

Everything else "looked" ok but needed a good cleaning. The float levels seemed fine and working properly.
_________________
Samba Member #95

[modok]

Don't soak anything overnight man. Just clean it out, solvent and brushes, little fine wire brushes work well.

[[email protected]]

The washers in your second pic are kind of like a little internal snap ring. You can push down the spring loaded center section, and gently pry them out with a small screwdriver. Thoroughly clean the little pistons that are underneath the springs, making sure they slide in the bores smoothly, and the piston bottoms are clean so they “seat” in the bottom of the bores. You can reinstall the washers by tapping them in with a similar diameter socket. Dirt, or corrosion holding the pistons open any can dribble excess fuel into the engine causing an overly rich condition.

[jpaull]

If the main problem is fouling spark plugs, why would you not post a picture of the fouled spark plugs first?

[[email protected]]

many times that's from guys using spark plugs which are simply too cold, and has nothing to do with the carburetors. You'd be surprised how many people think this makes the engine run cooler, and that's why they do it.
_________________
It's just advice, do whatever you want with it!

Please do NOT send me Private Messages through the Samba PM System (I will not see them). Send me an e-mail to john at aircooled dot net

"Like" our Facebook page at
http://www.facebook.com/vwpartsaircoolednet
and get a 5% off code for use on one order for VW Parts ON OUR PARTS STORE WEBSITE, vwparts.aircooled.net

[jpaull]