TheSamba.com :: View topic - Gas dripping out of exhaust

Sat Mar 31, 2012 1:00 pm

Hi, pulled my engine a couple weeks ago and put it back in last weekend.. all I did was cleaned it up and fixed an oil cooler leak (I hope at least). Put the engine back in and it won't fire up, I've checked most of the basics, but I don't think they're the problem

While the motors turning over, gas drips pretty continuously out of the clamp that connects the muffler and heater boxes. The carb is full of gas and when I feed it gas it goes into the intake..

I watched the inside of the carb while the motor was turning, it only sent a drop or two of gas into the intake yet the exhaust has 15+ drips in a matter of seconds. Did I extremely flood it to the point where gas is just sitting somewhere or what could be going on here?

74 std 1600dp

Sat Mar 31, 2012 1:17 pm

tht happened to me. check your rocker arms, a washer may have broke causing a loose arm.

Sat Mar 31, 2012 1:49 pm

unless I missed it I don't think thats the problem, they all looked good and appeared to operate correctly while I moved the pulley.. even my gaps are still good

Sat Mar 31, 2012 1:50 pm

The needle valve in the carb could be stuck open. Or it could just be badly flooded.

Sat Mar 31, 2012 3:27 pm

Try not to run it much if there's gas in the oil. Could ruin the bearings. Stuck needle and seat or bad float. Didn't mess with the fuel pump did you? If so, check the fuel pressure.

Sat Mar 31, 2012 5:20 pm

Happened to me 2 weeks ago. Float was bad.

Sat Mar 31, 2012 8:57 pm

Ok well I replaced the float, nothing looked wrong with it but I figure it's not going to. I seemed to get less gas out of the exhaust and finally it did a couple.. purr's? (getting spark I think) like it wanted to fire up, however it didn't. I saw that the fuel filter was completely full and then after a few more times cranking (I assume I have to get that extra gas out) the filter was empty and I ran out of gas.

Probably had 1-2 gallons before this happened anyways.

Before I read these posts about the float I pulled the carb off and held it over a bucket and turned the engine over, very few drops came out but the same happened to the exhaust.

Also when I went to replace the float, I pulled off the fuel line into the carb and a small amount of gas blew out of the line/carb like it was pressurized. I'm guessing thats more evidence towards a bad float.

Will get gas tomorrow and see what happens. Thanks for the help so far, will post an update.

Sat Mar 31, 2012 9:10 pm

Make sure you check your oil. Mine got way to much gas in it and ruined my pushrod tube seals. Hopefully this did not happen to yours.

vee dub dan wrote: Ok well I replaced the float, nothing looked wrong with it but I figure it's not going to. I seemed to get less gas out of the exhaust and finally it did a couple.. purr's? (getting spark I think) like it wanted to fire up, however it didn't. I saw that the fuel filter was completely full and then after a few more times cranking (I assume I have to get that extra gas out) the filter was empty and I ran out of gas.

Probably had 1-2 gallons before this happened anyways.

Before I read these posts about the float I pulled the carb off and held it over a bucket and turned the engine over, very few drops came out but the same happened to the exhaust.

Also when I went to replace the float, I pulled off the fuel line into the carb and a small amount of gas blew out of the line/carb like it was pressurized. I'm guessing thats more evidence towards a bad float.

Will get gas tomorrow and see what happens. Thanks for the help so far, will post an update.

Sun Apr 01, 2012 1:41 pm

Ok so I put my old carb back on (it was working), cleaned the spark plugs, checked the gap as well as tested spark from coil to distributor, all of the distributor wires and one of the spark plugs.

I have gas, spark and when I hand turn the engine I can hear/feel compression.

The only thing I changed was the back up lights.. before I have NO clue how they got power, there was no line to the coil but they worked. Awhile back I replaced the tranny and messed those up so I didn't have reverse lights, but now I have it wired up correctly. I've tried turning it over with that wire off (its attached the the carb choke) but no luck there either.

I still have a small amount of gas leaking out of the exhaust with a new carb and when I had a new float. Is it the (almost brand new) fuel pump?

Any opinions? ...

Sun Apr 01, 2012 2:03 pm

Try this:
Take the carb off and turn over the car to blow out whatever gas is in the exhaust. Then leave the carb off and supply fuel to the intake by using starting fluid or pour a small(less than tablespoon) amount of gas into the intake to make sure the engine fires without any "carb issues".

Once you know the engine will fire on it's own hook up the carb to the fuel pump as normal but do not install carb. Hold carb off to the side so you can see if the new fuel pump is pushing fuel out of the carb. Have a friend turn the engine over for you. Make sure not to move the throttle lever. Just hold the carb and see if fuel spills out on its own. If it does then you know it's the fuel pump.

If you want to check the float needle or level bypass the fuel pump and hook up a fuel source to the carb via gravity. If it leaks via gravity fed then its the needle or float level. Needle will leak instantly float will leak after a few seconds.

Sun Apr 01, 2012 2:14 pm

I'll try that later tonight when I can. Another thing is that when I went to swap the carb and pulled out the fuel line it felt like it was pressurized again which makes me wonder if the fuel pump is forcing too much

Sun Apr 01, 2012 2:26 pm

vee dub dan wrote: I'll try that later tonight when I can. Another thing is that when I went to swap the carb and pulled out the fuel line it felt like it was pressurized again which makes me wonder if the fuel pump is forcing too much

There should only be pressure in a fuel injected engine. If the line squirts fuel when you disconnect it from the carb then something is wrong with the pump. Put your finger over the opening in the line and feel how much pressure its pushing as the engine turns over(maybe wear some glasses just in case). You should be able to plug the line with a very small amount of force from your finger tip. Think about how little pressure the float uses to seal the needle in the carb. If it pushes past your finger then there's no needle that will seal it.

Sun Apr 01, 2012 3:16 pm

Wow

I am having a hard time reading the post

You need to check to see if you have gas in your oil from a bad fuel pump diaphragm-- when they go it fills the oil with fuel

This will destroy your motor immediately

Twice someone asked you to check your oil for fuel

Damn

Sun Apr 01, 2012 3:33 pm

JerryMCarter1 wrote: Wow

X2

I am having a hard time reading the post

You need to check to see if you have gas in your oil from a bad fuel pump diaphragm-- when they go it fills the oil with fuel

This will destroy your motor immediately

Twice someone asked you to check your oil for fuel

Damn

Sun Apr 01, 2012 3:45 pm

Guess I just forgot to mention that, I've had 3 people smell the dipstick and it doesn't seem to have gas in it. But it does seem like there's more "oil" in the case.
I'll more than likely still change the oil once i get it running.

Sun Apr 01, 2012 3:59 pm

no - you change the oil immediately !
my guess is that you have gas in your oil from a bad pump

Sun Apr 01, 2012 7:04 pm

Fogarty:

Followed your instructions and with the carb off and starter fluid it tried firing up. The fuel pump did not really force fuel up past my finger, but after replacing the pump it fired up. (and was shut off after verifying it would run for a 20~ seconds)

Thank you to everyone for your help and patience, going to enjoy driving it in the next week (weather permitting).

Sun Apr 08, 2012 1:40 pm

Going to bump and expand this..

Fired it up Friday and it sounded good, ran good. Tried to start it up today and it will not start.

The oil definitely has gas in it now, I really need to figure this out so I can change it before I run it.

Originally had a brand new fuel pump on the car, changed it and the car ran. When it wouldn't start up today, I changed to yet another fuel pump and it started leaking gas out of the exhaust. Put on the brand new one again and no leak, but doesn't start

--Brand new pump originally seemed to be leaking gas out of exhaust, but it might be deeper than this.
--Known working pump leaks gas out of the exhaust clamps, won't fire.
--Unknown condition fuel pump leaks gas into motor.

I changed carbs, no change so I switched back. Installed a new float and needle valve.

With the carb off I had NO gas at all dripping when the car was turning over. (gas did flow out when tipped forward, must be an overflow? came out of the bigger facet looking thing that goes into the middle of the chamber)

Fuel pump is feeding gas to the carb. I had the top of the carb off and the needle valve is functional (gas pours out fast when not being blocked, maybe too fast? No pressure tester yet)

It actually didn't even try to start when putting some starter fluid directly into the intake. I timed it on Friday so spark is fine.

I'm going to buy a new fuel pump this week from a local VW store, but I'm still not convinced it will help.

Gas. check
Spark. check
compression. check
Virtually any sort of test I do comes out working

What the heck is going on..
Is it possible that the case is too full...? Again; I know it needs dumped, but I can't waste $15-30 on several oil changes. Would love to know whats going on before that happens..

Mon Apr 09, 2012 4:27 am

Sounds like the pressure is way too high. Did you use gaskets when you installed the new pump. The more gaskets you use, the lower the pressure will be. May be time to get a gauge to measure that gas pressure.

Mon Apr 09, 2012 7:23 am

you have BIG troubles my friend ,...
like a BIG engine fire ,.. and now you are messing with starter fluid ?

if she does start up ,..or even back fires ,... the exhaust will explode like a bomb and the whole car will go up in flames ,....along with you , your garage and even the house --
let it dry out ,...and then try replacing the carb ,...
or just take the car to a real mechanic ,..before something VERY bad happens