Installed new carbs, now have flames shooting out the exhaust!

The VW Beetle. Everything about bugs!

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Dean...
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Re: Installed new carbs, now have flames shooting out the exhaust!

Post by Dean... » Fri Aug 11, 2017 2:00 am

Great advice, I will give that a go.

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Dean...
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Re: Installed new carbs, now have flames shooting out the exhaust!

Post by Dean... » Sun Aug 13, 2017 6:05 pm

Hey everyone!

Today I pickup a Kombi that I just bought, so work on the Beetle won't start until this afternoon. But....

When I gave the carbs a good clean, I think I could have missed an important section. In the picture, I have circled a couple big holes that I don't remember cleaning. I didn't clean them because I thought they were to do with the choke, which is not being used, but now I'm wondering if I should have made sure they were clean.

Anyways, the plan is to check the flow of fuel. If that all seems ok, then I'll probably reinstall the twin 40's I have. They were rebuilt very recently by the mechanic that I'm not happy with, but I have to keep moving on this because I want my car back on the road.

Thanks again for everyone's tips and advice, you haven't no idea how much I really appreciate the help!

Cheers
Dean[IMG]//uploads.tapatalk-cdn.com/201708 ... 399063.jpg[/IMG]

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Re: Installed new carbs, now have flames shooting out the exhaust!

Post by Piledriver » Sun Aug 13, 2017 8:49 pm

I read a great article on Weber chokes recently, maybe here, UAC, or TOS,
IIRC it was posted by FJCamper.
There are possibly still active choke bits in your carbs,
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Re: Installed new carbs, now have flames shooting out the exhaust!

Post by sideshow » Sun Aug 13, 2017 9:51 pm

If the cold start passage has been drilled, one must run the bits (at least the internal ones) or they will leak copious amounts of fuel into the engine. One doesn't need the linkage unless you want that on purpose...I've never seen it used on an ACVW application.
Yeah some may call it overkill, but you can't have too much overkill.

Dean...
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Re: Installed new carbs, now have flames shooting out the exhaust!

Post by Dean... » Mon Aug 14, 2017 2:01 am

Ok, I'm working on it as I speak

I can't blow fuel through the lines from the back of the car to the tank. I even tried compressed air, but my guess is the fuel pump is doing it from happening.

At least for now, I'm going to pull these 44's and put the set of 40's that were recently rebuilt.

Here I go...... [IMG]//uploads.tapatalk-cdn.com/201708 ... d641e4.jpg[/IMG]

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Re: Installed new carbs, now have flames shooting out the exhaust!

Post by Piledriver » Mon Aug 14, 2017 2:20 am

Yep, the fuel pumps check valve (if up front) is going to prevent that test from working, but I still suggest temporarily plumbing around it and doing it at some point, if only as a sanity test.

Just blowing the line out into clean paper towels can also be informative. (tank side plugged off)

Note the line coming off the tank is supposed to be ~12" long or so to allow the tank to pop up in a frontal impact... without disconnecting.
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Dean...
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Re: Installed new carbs, now have flames shooting out the exhaust!

Post by Dean... » Mon Aug 14, 2017 2:46 am

Thanks for that info. Yes I did notice some length in the hose when I connected the pump.

I just found my first possible issue : the nuts that attach the manifold to the heads, they were not very tight. This is the case for the left side, I'm about to remove the right side now. I torqued them up using a torque wrench, so I don't understand why they lost a lot of tension...

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Dean...
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Re: Installed new carbs, now have flames shooting out the exhaust!

Post by Dean... » Mon Aug 14, 2017 3:13 am

The right side is off. Nuts were a little tighter than the left. The stud at cylinder 1 actually came out. Time to swap the carbs on the manifold.

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Re: Installed new carbs, now have flames shooting out the exhaust!

Post by Dean... » Mon Aug 14, 2017 5:45 am

Carbs have been swapped over on the manifolds, and the right setup is done.

I've hit a snag on the left. The number 3 stud for the manifold has decided to come out and take the thread with it.

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Re: Installed new carbs, now have flames shooting out the exhaust!

Post by Dean... » Wed Aug 16, 2017 5:28 am

Time for an update!

It's running!!!

I bought a kit to install a new thread into the head, and then proceeded to put the car together.

One problem I have is that number 2 cylinder is drawing a lot more air than the rest. At least 2 points more according to my snail gauge. I've checked the air bypass and it's closed. I have spoken to a mechanic and he reckons the shaft is twisted. I have tried to twist it back, but so far I haven't been successful.

The downside is that when I'm slowing down with my foot off the accelerator, the engine is popping out the exhaust, which I think is due to the difficulty in tuning the carbs with one cylinder sucking too much air. What I've done though is adjusted that cylinder last, but I'm yet to test drive it since. That will happen tomorrow now.

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