Single carb problem, fuel to only one barrel |
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Single carb problem, fuel to only one barrel |
terrymason |
Dec 3 2006, 11:27 AM
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#1
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Member Group: Members Posts: 346 Joined: 23-November 05 From: Virginia Beach Member No.: 5,174 |
Could you guys take a quick look at this video of my carb:
http://drunkencrab.com/temp/carb.mpg The barrel on the right is to the front of the car if it matters. This is a single progressive carb (which I have no experiance with up till now). Should I be seeing fuel to both barrels, or is this working as it should? My car runs pretty poorly, and has no real power (I have to race the engine to take off). Thanks guys! |
ejm |
Dec 3 2006, 11:44 AM
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#2
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I can see the light at the end of the tunnel Group: Members Posts: 2,702 Joined: 3-February 03 From: Massachusetts Member No.: 224 Region Association: None |
Looks to be working correctly, the second barrel opens mechanically around 3/4 throttle. These carbs generally have a big off-idle flat spot that's worse in cooler weather. That may be why to have to race it to take off?
Had one of these carbs on my first 914, always wanted to give it the float test. |
terrymason |
Dec 3 2006, 11:51 AM
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#3
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Member Group: Members Posts: 346 Joined: 23-November 05 From: Virginia Beach Member No.: 5,174 |
OK, that makes sense. I think the air filter hasn't been cleaned in a couple of years, and it already seemed a little better when I took the old one off.
Thanks for the help. |
terrymason |
Dec 3 2006, 11:53 AM
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#4
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Member Group: Members Posts: 346 Joined: 23-November 05 From: Virginia Beach Member No.: 5,174 |
well, along the same lines - the electronic choke doesn't seem to be working. Is there a simple way to test that? Should the flaps move as I turn the key off and on?
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So.Cal.914 |
Dec 3 2006, 11:55 AM
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#5
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"...And it has a front trunk too." Group: Members Posts: 6,588 Joined: 15-February 04 From: Low Desert, CA./ Hills of N.J. Member No.: 1,658 Region Association: None |
Back in 82 I ran one of those set ups for about two months and it never
ran right. Its like pouring raw fuel into the cylinders. You really would be better offf running two one barrels. |
terrymason |
Dec 3 2006, 12:01 PM
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#6
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Member Group: Members Posts: 346 Joined: 23-November 05 From: Virginia Beach Member No.: 5,174 |
Back in 82 I ran one of those set ups for about two months and it never ran right. Its like pouring raw fuel into the cylinders. You really would be better offf running two one barrels. I totally agree. I'm getting two dellorto carbs from a guy on this board, but it's going to be some time before I get them - and probably longer before I learn how to sync them. The car idles great, and works fine under speed, but when the light turns green I really need to rev it up to 3k to gently pull out. I think 50% of my problem may have been the air filter, and I've put about a can of carb cleaner down it - that may have helped. I'd really like to get a good understanding of this carb, and how it works, in case I need to continue running this for a while. |
So.Cal.914 |
Dec 3 2006, 12:15 PM
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#7
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"...And it has a front trunk too." Group: Members Posts: 6,588 Joined: 15-February 04 From: Low Desert, CA./ Hills of N.J. Member No.: 1,658 Region Association: None |
Mine ran the best after a good tune up. What color are your plugs? Is it probably
running really fat at the low end, it's the nature of the beast from my experience. Sorry I don't have better news for you. |
Flycut |
Dec 3 2006, 12:25 PM
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#8
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Member Group: Members Posts: 171 Joined: 6-August 06 From: Hawaii Member No.: 6,587 |
You really need to make sure the electric choke is working properly, Make sure your positive from the coil is hooked to the male connector at the front of the carb. I would also advance timing by ear, Meaning until you have detonation at hard throttle while driving and then back off timing until detonation is not present.
Make sure all the ports your not using on the carb are plugged up. What kind of dizzy are you running? |
ejm |
Dec 3 2006, 12:43 PM
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#9
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I can see the light at the end of the tunnel Group: Members Posts: 2,702 Joined: 3-February 03 From: Massachusetts Member No.: 224 Region Association: None |
QUOTE I would also advance timing by ear, Meaning until you have detonation at hard throttle while driving and then back off timing until detonation is not present Good way to cook an engine..... just because you can't hear it does not mean it's good..... use a timing light |
Flycut |
Dec 3 2006, 01:00 PM
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#10
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Member Group: Members Posts: 171 Joined: 6-August 06 From: Hawaii Member No.: 6,587 |
QUOTE I would also advance timing by ear, Meaning until you have detonation at hard throttle while driving and then back off timing until detonation is not present Good way to cook an engine..... just because you can't hear it does not mean it's good..... use a timing light I agree and disagree.....I will time my engine with a timing light and then push the advance beyond.....Always get a better running engine. I've been doing this for 20 years to various aircooled rides and have never cooked an engine. The 32/36 carb will never run well unless timing is maxed out! It will be obvious timing is to advanced when car has a hard time cranking when starting, When this occurs retard timing until engine will crank normally. Advance will be beyond the 27 degrees reccomended for injection timing. (IMG:style_emoticons/default/chowtime.gif) Try it you might like the way your car runs under 1500 RPM. There are book facts and then real world tried and true findings. IMO (IMG:style_emoticons/default/biggrin.gif) |
terrymason |
Dec 3 2006, 01:21 PM
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#11
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Member Group: Members Posts: 346 Joined: 23-November 05 From: Virginia Beach Member No.: 5,174 |
You really need to make sure the electric choke is working properly, Make sure your positive from the coil is hooked to the male connector at the front of the carb. I would also advance timing by ear, Meaning until you have detonation at hard throttle while driving and then back off timing until detonation is not present. Make sure all the ports your not using on the carb are plugged up. What kind of dizzy are you running? I have just started getting into the car, and have no idea what dizzy I have - is there an easy way to tell? And I'm not really sure what you mean by detonation - I assume that the motor will make a different noise? |
So.Cal.914 |
Dec 3 2006, 02:37 PM
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#12
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"...And it has a front trunk too." Group: Members Posts: 6,588 Joined: 15-February 04 From: Low Desert, CA./ Hills of N.J. Member No.: 1,658 Region Association: None |
Detonation = pinging.
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Flycut |
Dec 3 2006, 05:11 PM
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#13
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Member Group: Members Posts: 171 Joined: 6-August 06 From: Hawaii Member No.: 6,587 |
Post a pic, (IMG:style_emoticons/default/bye1.gif) and or give us some numbers off the body of the distributor.
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SGB |
Dec 3 2006, 05:15 PM
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#14
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just visiting Group: Members Posts: 4,086 Joined: 8-March 03 From: Huntsville, AL Member No.: 404 Region Association: South East States |
Have you changed the spark plugs? That can be a big proponent for combustion.
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Joe Bob |
Dec 3 2006, 05:20 PM
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#15
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Retired admin, banned a few times Group: Members Posts: 17,427 Joined: 24-December 02 From: Boulder CO Member No.: 5 Region Association: None |
That carb was designed for a PINTO...remember them? Explode on impact????
Give it the float test and get some duals.... |
Jake Raby |
Dec 3 2006, 05:34 PM
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#16
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Engine Surgeon Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
The best tool for working on these carbs is an 8 pound sledge hammer.
I take pride in crushing every one that I get the opportunity to interact with. Horrible, absolutely worthless! |
bd1308 |
Dec 3 2006, 05:41 PM
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#17
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
i thought about covering the runners with old cyrix chips, and then lighting them up with 5 volts of power to keep the runners warm.
(IMG:style_emoticons/default/idea.gif) |
Flycut |
Dec 3 2006, 06:52 PM
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#18
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Member Group: Members Posts: 171 Joined: 6-August 06 From: Hawaii Member No.: 6,587 |
The best tool for working on these carbs is an 8 pound sledge hammer. I take pride in crushing every one that I get the opportunity to interact with. Horrible, absolutely worthless! (IMG:style_emoticons/default/agree.gif) Engine will be a totally different animal with duals, And a mallory. |
PORobinSCHE |
Dec 3 2006, 07:44 PM
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#19
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Member Group: Members Posts: 421 Joined: 22-July 06 From: Orlando,Fl Member No.: 6,484 |
QUOTE I would also advance timing by ear, Meaning until you have detonation at hard throttle while driving and then back off timing until detonation is not present Good way to cook an engine..... just because you can't hear it does not mean it's good..... use a timing light I agree and disagree.....I will time my engine with a timing light and then push the advance beyond.....Always get a better running engine. I've been doing this for 20 years to various aircooled rides and have never cooked an engine. The 32/36 carb will never run well unless timing is maxed out! It will be obvious timing is to advanced when car has a hard time cranking when starting, When this occurs retard timing until engine will crank normally. Advance will be beyond the 27 degrees reccomended for injection timing. (IMG:style_emoticons/default/chowtime.gif) Try it you might like the way your car runs under 1500 RPM. There are book facts and then real world tried and true findings. IMO (IMG:style_emoticons/default/biggrin.gif) FLY, appx how far are you pushing the Dist past 27 degrees? 30-32? i would do the same on my old 74 Vette. stock time it then advance till it pinged. after that back it off appx 3 deg on the timing wheel. turned out i was at 35 degrees . ran super on bottom and mid range. i didn't race it so never worried about fall off on the top. my 02 Robin |
bd1308 |
Dec 3 2006, 07:57 PM
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#20
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Sir Post-a-lot Group: Members Posts: 8,020 Joined: 24-January 05 From: Louisville,KY Member No.: 3,501 |
Hmm, I'm wondering what the HEAD temps are when you do this?
I have found that advancing timing leads to higher temps.... |
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