running on 3 cyls... at my wit's end (solved)

[Singerdude]

Hi guys, I got a 2276 with 44 idf's in a buggy. I'm used to losing a cylinder every once in a while at low RPM's and stopping to blow air through the iddle jets and then evrything goes back to normal.

But now #3 refuses to cooperate. It feels like a plugged Iddle jet because it sputters at low RPM's but will pick up around 3k...

So here's what I've tried so far to no avail:

Changing fuel filter
Blowing air through gas lines
Dismantling and thouroughly cleaning offending carb (carb cleaner and compressed air everywhere)
Swapping plug wires
Swapping plugs
New distributor cap
New rotor

Next thing I wanted to check was compression but I don't have the proper fitting for 12 mm plug holes (old motor had 14mm plugs and I just have the one fitting)


Now I pretty much exhausted my limited knowledge and capacity so if someone thinks of something I left out, I'm all ears, we are at the beginning of a 3 days weekend here in Canada and the sun is out shinning, wich adds salt to the wound

Thank you

[Bama Dave]

I cannot say I have had this exact issue, but I would go with the obvious. Check that timing is correct and all wires are in correct order. Check valve lash. Check that #3 is actually getting fire to the plug. Check plug gap. If all of that is as it should be, then it is the carb. Something's plugged and you haven't cleared it yet.

Yes, it could be that #3 has no compression, but that is not as likely, unless you have not stated something that may affect that.

If you are constantly losing a cylinder due to clogged carb, you need better filtration. I run 2 fuel filters, just because. One at the tank before the pump and one by the tranny. Cannot hurt.

Let us know what you find.
_________________
David Richerson

!964 Beetle Sedan
1970 Beetle Sedan
1971 Super Sedan
1972 Baja

[FreeBug]

You cleaned he idle jets, now try the idle air passages.

[modok]

Sucked a chunk out of the gasket?
If it has ported out stock castings, check for "hole in the port"

It can take YEARS for a paper thin spot in a port to become a hole.

[Singerdude]

[modok]

Gasket good?, ok, did not know if you had removed the entire manifold.
Like this:

[Singerdude]

Oh I see, I'll shove a flashlight in there.

Manifold paper gasket seemed good but I have some new ones so I'll change it just in case.

[Bama Dave]

For the tank, i believe it may be best to pull it out of the car clean it. Put a new screen at the bottom, too. That old gas cap gasket is likely providing some of the problem, as it decays away and bits of gasket flow to the rear.
_________________
David Richerson

!964 Beetle Sedan
1970 Beetle Sedan
1971 Super Sedan
1972 Baja

[modok]

I run two or three filters, sometimes more. You only need one good FINE filter but just one is never enough.

The tank is supposed to have a coarse screen, and the carb is supposed to have a fine screen right before the needle/seat. That's three already, and if any of those are missing it's a fine idea to make up for it.
If the tank is dirty I use a HUGE GM filter right under the tank, which could hold a cup of dirt. Don't want to clog the long line in the tunnel

Sometimes I have to re-drill jets, or just poke the ass end of a drill through.
I assume it's oxidation in there, that compressed air won't budge, but hole is so small you can't tell..........so when I build carbs I gauge every hole I can reach.

[Singerdude]

Negative on the hole in the port, no light through whatsoever.

I use Meyle filters but I wonder if there are some re usable stainless steel ones? Are they any good?

Carb is off once again for a round of cleaning, I'll let you know if it solves anything.

[[email protected]]

it helps if you SWAP jets with another cylinder, and note if the problem moves or stays. This helps isolate the problem. Same with plug wires to rule out a bad wire.
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[Mikedrevguy]

Check connections? I succinctly dropped a cylinder and after checking everything (plugs, wires, valves, jets, blah blah) on the 3/4 side moved over to the 1/2 side and discovered the adapter had spun off the plug but there was just tight enough fit to keep the wire connected to the plug, but not enough to have solid connection.
Long story short- hope it's something simple.
Rev

_________________
74 1303 (RevBug): plan for German Look
76 914 with 2260
79 VW Iltis
69 Bwajaja
"The wise speak because they have something to say; while the foolish speak because they have to say something." Plato

Illigitimi non-Carborundum!!

[Singerdude]

Mikedrevguy, I don't use the adaptors on my plugs, plus I swappeg plugs and the problem persisted. I wish it was that

So, I just finished cleaning the carb through and through. I can't figure any hole/passage I didn't cover. Unfortunately, it is late here so I'm gonna have to wait till tomorrow morning before I can start it to see if It did any good.

John, I swapped the 3 and 4 jets. Also I cleaned them with the only thing small enough that I had lying around: a single strand taken out of a stainless steel braided wire. Just to make sure, like Glen said that there wasn't any restrictive stuff that air alone wouldn't get out.

[modok]

Do these have the starter circuits?

[Singerdude]

I don't think so.

[heimlich]

Wouldn't a hole in the piston cause the same thing? I had a Beetle that ran on 3 cylinders only to find a hole in one piston.

[Singerdude]

It would, but what makes me think it is something else is that the "dead" cylinder will wake up above 3k RPM's. so it feels just like an obstruction of the iddle jets.

[[email protected]]

Swap plugs. Then plug wires with adjacent cyl.

If that doesn't do it, check compression (valve adj?)
_________________
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
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and get a 5% off code for use on one order for VW Parts ON OUR PARTS STORE WEBSITE, vwparts.aircooled.net

[Singerdude]

Already done swapping plugs and wires and it didn't change anything. Maybe I wasn't as thourough with the cleaning the first time, we'll see tomorrow morning if the second time I dislodged something and we're back to happy

[dsrtfox]

Maybe swap the carbs from side to side. You won't be able to hook up the linkage up but it will idle and see if the dead cylinder moves to the other side...