Ashcreek speedster problem

Does fuel pump run and squirt fuel when attached to car?  Maybe it isn't getting juice when key is turned to start?  I'd double check ground again.

Remove a fuel line at the carburetor and see it fuel squirts out when the key is on.  If not, suspect the pump or something else in the line between pump and carb.  If fuel squirts out, then look elsewhere, like spark.

I checked all the polarity, and double checked the wiring. A trickle comes out 

at the carbs. Spark is perfect. It seems the pump doesn't have any balls....Sorry about 

the French. I know these pumps are set for a few lbs. to satisfy the Webers. Can it 

be the pump is sensing some back pressure as if the carb was full?

I have some old cheap pumps at work. Tomorrow I'll install one and see what

it does. Maybe the new pump is shot. I'll let you know tomorrow.

Big surprise. Has anyone put something on a shelf thinking

someday they will use it? Well thats what happened. Back many 

years ago I bought some stainless steel braided fuel line. I had 

a big piece left over, and decided to put it on my motor. I can't 

remember how old it is, but it's at least 15 years old. After installing 

it on my new motor, it seemed OK. That was about 2 years ago.

During that time period, the inside rubber, underneath the braid,

the rubber started to decompose. It got into the carb and formed 

a black deposit on the bottom of the bowl, the jets, and the needle 

valve. It blocked the carb shut, and created a situation that I have 

never seen. By being so blocked off, it must have affected the regulator 

on the pump. I took the carbs off disassembled them cleaned up

the mess and all is good. I marched into my storage area and started 

throwing things away. It was great to hear my motor again.

And I thought I was a hoarded!  They didn't know what ethanol was 15 years ago.  We ate corn on cob and corn whiskey -- who'd think it would make it in to our gas tank.

Great job of hunting down the culprit!

I think I need to re jet my carbs. My motor is 74 stroke and 90 mm pistons.

I have 44mm Webers. It has strong idle, but pops and hesitates coming off

idle. I had this problem on a 356, and cured it with bigger idle jets. I'm not

sure if these Webers are jetted for a motor my size. Are there any charts

or advice to cure this? 

Check that both carbs are sync when opening the throttle. If one is opening. Before the other that can give you a hesitation off idle.

Carbs are in perfect sync. I use a synchronizer and I have been balancing

carbs for a long time. Are there numbers for the jets on the 44 Idf webers

used on VW?

ashcreek posted:

I think I need to re jet my carbs. My motor is 74 stroke and 90 mm pistons.

I have 44mm Webers. It has strong idle, but pops and hesitates coming off

idle. I had this problem on a 356, and cured it with bigger idle jets. I'm not

sure if these Webers are jetted for a motor my size. Are there any charts

or advice to cure this? 

74 x 90, so about 1885 cc? What size are your Venturis and intake valves? 44 IDF's may be a bit on the large side for an engine that size unless the Venturis have been downsized a little. Here's a great article from the archives by Mark Harney on tuning Webers.

And here's an excerpt from it that may explain why the response is a little weak just off idle:

Venturi selection - For engines that rev pretty high (6000-7000 rpm), you are best off choosing vents that are about 2 to 4mm smaller than your intake valve size.For engines that are set up for torque, like bus engines, and other torque- happy applications, you can go a little smaller on the vents and get better low end response. For these, I'd recommend 4 to 6mm smaller than your intake valve size.

So what happens if your vents are too big? You'll have reduced air-speed at low RPMs, which makes tuning harder. Air speed is one of the things that tells your different fuel circuits when to start to come on. It will be soggy down low.

So what happens if your vents are too small? The undersized vents will restrict your engine's ability to breathe at higher RPMs.

How critical is it? Not terribly, but if you're way off it will matter, and you will feel it. Putting 40 vents in a set of 44 IDFs with 40mm intake valves will be pretty soggy down low. Sticking with the 36's would be about right. Putting 28 vents into a set of 40 IDFs on an engine with 40mm intake valves will limit your top end noticeably as well. A set of 44 IDFs, for example, can me made to work on many engine sizes with the standard 36 vents, but you might find that you could optimize them better if you are willing to spend the money and try some different vents that would be ideal for your application.

ashcreek posted:

Carbs are in perfect sync. I use a synchronizer and I have been balancing

carbs for a long time. Are there numbers for the jets on the 44 Idf webers

used on VW?

balancing each cylinder is important, but it's also important that they open together. one thing I notice more and more is that one link may be longer or the bracket on the carb has different pickup points which changes the ratio when opened. I know myself I said I checked it and later went back and found I was off slightly which caused my problem to begin with. Mitch is right about the venturi size. Mark did a good job explaining everything. It's not easy to tune a motor over the net. I would check your idle jets [size] and mains along with air jets.  most 2.0 liter motors I start with 55 idle jets. 135-140 mains and a big air jet 180-200. the emulsion tube is F11 unless racing. These are guide lines. it really depends on your motor. size, compression, cam, tall or short intakes, and where you are located.

Good Luck!

This makes perfect sense. On my 356 motor I have 40mm Webers.

I never measured the Venturi's but I know when I look down the carb,

the venturi's are noticeably smaller. When I look down the throats of 

my 44's there seems to be no venturi at all. I have a set of webers off

a 356 that ran great. Maybe I'll try them out.

Had similar issue with my '57 1600 Super. Don't forget to measure the stroke volume of each carb's accelerator pump. If I remember correctly, the stroke volume should be between 0.4 - 0.6 cc per stroke.

You can fabricate a measuring tool with a syringe. Gordon posted a pic of one that he made...

Adjust the stroke volume by loosening the nut on the accelerator pump rod, position the measuring tool below the pump nozzle in the carb throat, fully depress the accelerator pump and measure gas volume in measuring tool. Adjust stroke of accelerator rod to deliver proper volume.

Hopefully this is useful info for you.  

I'll check the volume tomorrow. Does anyone run 44 IDF's? If so, what size

venturi's and jets?

I just finished switching the 44IDF's with a set of Webers from a 912. Wow!

I haven't driven it yet, I'll try it tomorrow and give a report.

Thanks for all the great info, it was very helpful. I drove the car today, and it 

was great. Lots of low end torque, and good high end. You were right, the venturi's

on the 44's were way too big. It had a great idle and initial response, but dropped

off immediately. I think it was just running on the accelerator pumps. Now with

the 40mm webers off on 912, the thing runs great. I didn't want to go through

all the hassel of measuring the venturi's, I figured if they were set up for a 1600cc

motor, they should be good for me. The question is, what do I do with the 44's?

should I try to put smaller Venturi's in there, and figure out the jetting?

One more thing. I want to put a set of Babymoons on my car.

Are there any aftermarket hubcaps around? I have 5 bolt 15" rims.

I'd sell them and get some 40s-- IDFs or Dellorotos if you can find them.

VW guysLOVE to overcarb everything, because the bragging rights of saying you have a 140 hp engine apparently beats having something that is fun to drive. You'd have no trouble selling them.

coolrydes has about fifty sets of carbs for sale

Stan Galat, '05 IM, 2276, Nowhere, USA posted:

I'd sell them and get some 40s-- IDFs or Dellorotos if you can find them.

VW guysLOVE to overcarb everything, because the bragging rights of saying you have a 140 hp engine apparently beats having something that is fun to drive. You'd have no trouble selling them.

Unless you got a oval window with a built 2053 with 48 IDA's.  

I like the idea off selling them. The thought of trying to switch venturi's

jets, and all the rest, including putting them on and off, means, lots of gaskets

time, and Motrin for my back. The 40's seem to work. Now I just have

to find a pair to replace them, so that when i finish my 912 motor, I'll

have something to put on. I can't seem to find any inexpensive hub caps.

i have to stop spending money of this thing, It's starting to tap me out.

ashcreek posted:

 

I have to stop spending money of this thing, It's starting to tap me out.

I almost spit out my coffee.

Ahhh... err... ummm... Welcome to the Madness!

WOLFGANG posted:

And I thought I was a hoarded!  They didn't know what ethanol was 15 years ago.  We ate corn on cob and corn whiskey -- who'd think it would make it in to our gas tank.

We've been blending ethanol in gasoline for over 30 years.

I picked up my moons from Sierra Madre.  I forget what I paid for them. West Coast Metric used to also sell them.

Thanks, Sierra Madre had the Moons. My latest need is the sleeve that goes 

in between the back of the steering wheel  and the directional signal assy.

I checked with Henry at Intermeccanica, and no good. Any ideas?