| View previous topic :: View next topic |
| Author |
Message |
sslick
Samba Member
Joined: July 28, 2005
Posts: 100
|
 Posted: Mon May 28, 2012 7:37 am Post subject: Carb flooding... |
 |
|
| Just installed a fresh built EMPI HPMX-carbed 1914cc engine into my Ghia. After a ride, shut the engine off, come back 10 min. later, and one of the two carbs is literally drinking gas. I can hear it, "gulp, gulp", and I can see it if I remove the air cleaner. The carb is also leaking at this point. For the most part, the engine runs well. It idles great and runs good in the higher rpm's, but low end I'm getting popping and misses. Cruising at around 40mph in 4th gear it's the same...popping. If I step on the gas slowly, it'll clear up and start to pull. Could this be related to the flooding issue? I'm thinking that I have a float sticking, but I'm new to these carbs and really don't want to take it apart. Any ideas? |
|
| Back to top |
|
 |
vwracerdave
Samba Member
Joined: November 11, 2004
Posts: 8038
Location: OKLAHOMA
|
| Posted: Mon May 28, 2012 8:36 am Post subject: |
|
|
It could be a stuck float. A quick check is to remove the fuel lines and run the engine till it dies and the fuel bowls are dry. give the carb top a few light taps and then hook up fuel lies and start engine. If it continues then you'll hve to remove the carb top.
Have you checked what your fuel pressure is?
_________________
2010 Sportsman ET Champion - Mid-America Dragway - Arkansas City, KS
1997 Sportsman ET Champion - Thunder Valley Raceway Park - Noble ,OK
Featured in Dec. 2001 HOT VW's Magazine page 63
Watch my racing video's http://www.youtube.com/user/okvwracer/videos |
|
| Back to top |
|
|
sslick
Samba Member
Joined: July 28, 2005
Posts: 100
|
| Posted: Tue May 29, 2012 9:05 am Post subject: |
|
|
| vwracerdave wrote: | It could be a stuck float. A quick check is to remove the fuel lines and run the engine till it dies and the fuel bowls are dry. give the carb top a few light taps and then hook up fuel lies and start engine. If it continues then you'll hve to remove the carb top.
Have you checked what your fuel pressure is? |
I'll try that and see what happens. I've tapped on the carb to see if that would help already, but only with it full of gas. It makes sense to empty the bowl first.
No, I haven't checked fuel pressure yet. I'll get back to you on that. Where should I be (psi) with these carbs (HPMX)?
Thanks raverdave. I'll be getting back to you.
Hey, do you think that the float problem would be related to the low end popping? |
|
| Back to top |
|
|
smitty24
Samba Member
Joined: April 28, 2008
Posts: 2186
Location: Salem, Oregon
|
| Posted: Tue May 29, 2012 12:20 pm Post subject: |
|
|
I think the HPMX/Weber needs 3 psi of pressure. Mine originally had 8.5 at idle  with stock pump and literally shot fuel across the driveway when I removed a couple lines. Are you running a stock pump or electric? Regulator? For starters, is your pump adjusted along with floats and jetting for your correct elevation? |
|
| Back to top |
|
|
sslick
Samba Member
Joined: July 28, 2005
Posts: 100
|
| Posted: Wed May 30, 2012 8:11 am Post subject: |
|
|
| smitty24 wrote: | | I think the HPMX/Weber needs 3 psi of pressure. Mine originally had 8.5 at idle :shock: with stock pump and literally shot fuel across the driveway when I removed a couple lines. Are you running a stock pump or electric? Regulator? For starters, is your pump adjusted along with floats and jetting for your correct elevation? |
I'm running a stock pump w/out regulator. Everything should be adjusted/jetted/dialed in, etc. I paid a really reputable builder a lot of dough to build this turn-key for me and I really don't want to (and shouldn't have to) mess with stuff. I'm willing to try running the carbs dry and tapping on the flooding one to release the stuck bowl (if that's the case). I'm going to check fuel pressure as well. I also plan on speaking with my builder today about this. I'll let you know what I find. |
|
| Back to top |
|
|
DarthWeber
Samba Member
Joined: November 24, 2007
Posts: 7557
Location: Whittier,CA
|
| Posted: Wed May 30, 2012 12:53 pm Post subject: |
|
|
| sslick wrote: | | I really don't want to (and shouldn't have to) mess with stuff. |
Oh but you've got to show your VW motor a little love once in a while. 
_________________
| Mitey62 wrote: | | Swapped the Compufire for a Bosch blue and some points I had sitting around, started 1st crank. Took her out for a drive, pulls harder, more RPM, and runs smoother. I think I'll be sticking with points from now on. |
| RockCrusher wrote: | JB weld the case halves....that'll keep the fretting to a minimum.  |
|
|
| Back to top |
|
|
sslick
Samba Member
Joined: July 28, 2005
Posts: 100
|
| Posted: Sun Jun 03, 2012 8:57 am Post subject: |
|
|
| Flooding issue has been squashed. Just a stuck float. Stupid me, forgot to plug the fuel line back into the carb, fired it up, and guess what??? Gas everywhere!!!! I was wondering why it ran so bad for so long (about 30 seconds....enough to make quite a puddle of gas)! Thankfully, no fire! Could've lost everything...the engine, the car, the garage. Live and learn...live and learn! |
|
| Back to top |
|
|
sslick
Samba Member
Joined: July 28, 2005
Posts: 100
|
| Posted: Sat Jul 07, 2012 10:10 am Post subject: |
|
|
OK, so I was wrong. I'm still having the same problem.
Here's what happens: Take the car for a ride, get it good and warm. Shut it off. After about 5 minutes after it's shut off, you can hear the fuel start to move inside the carb. Again, it's just one of the carbs (the driver's side, both barrels). Look down the barrel and you can see fuel just dumping into the head. This will go on until there's no more gas in the line (up to the fuel pump).
What I've done so far:
Set float height, switched floats/needles between the faulty carb and the good one, spacers under the fuel pump to lower pressure, and yesterday just installed a pressure regulator and set it at 2.5psi.
Guess what? Still flooding! After speaking to my local mechanic, he seems to think that the fuel is actually boiling in the carb, which is creating a vacuum (is it called percolating/percolation?). I suppose this would make sense...the carb(s) are hot. But, why just one carb? Why so hot? It was also suggested that I buy/make phonelic spacers for them to break the heat transfer between the manifold and the carb. Any other suggestions/opinions? |
|
| Back to top |
|
|
|
