what's wrong?, gurgle, pop, even died |
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what's wrong?, gurgle, pop, even died |
seanery |
Apr 21 2004, 06:53 PM
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#1
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waiting to rebuild whitey! Group: Retired Admin Posts: 15,854 Joined: 7-January 03 From: Indy Member No.: 100 Region Association: None |
OK, so last week the car ran wierd on saturday. I blew the jets out (they seemed fine) replaced the o-rings, cleaned the K&N's and it still does it. It smells a bit rich, but it always has. It will idle fine, but if I go out for a drive it's just not right. Could it be valve adjustment time?
Thanks in Advance, I'm going to the track Saturday and don't wanna have to wrench on it there. |
lapuwali |
Apr 21 2004, 06:59 PM
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#2
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Not another one! Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743 |
Not much detail there. What's "wierd"? Has it ever run correctly with these carbs?
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seanery |
Apr 21 2004, 07:04 PM
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#3
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waiting to rebuild whitey! Group: Retired Admin Posts: 15,854 Joined: 7-January 03 From: Indy Member No.: 100 Region Association: None |
it ran fantastic up until Saturday. Nothing has changed and it's been driven a couple tankfuls already this year.
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lapuwali |
Apr 21 2004, 07:25 PM
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#4
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Not another one! Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743 |
Is the problem just off idle, at light throttle, at full throttle?
Does it pop and bang off throttle or on? Have you checked ignition timing? Are you running points or electronic ignition? |
Mark Henry |
Apr 21 2004, 07:32 PM
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#5
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
I could be a bit of junk in the carb circuit itself. I often have to remove and disassemble the carb totally, clean with carb cleaner and blow it out. If you do it slow it's quite easy to do.
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Bleyseng |
Apr 21 2004, 08:24 PM
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#6
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Aircooled Baby! Group: Members Posts: 13,035 Joined: 27-December 02 From: Seattle, Washington (for now) Member No.: 24 Region Association: Pacific Northwest |
Damn carbs, put the Djet back on........ (IMG:style_emoticons/default/biggrin.gif)
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seanery |
Apr 21 2004, 08:35 PM
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#7
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waiting to rebuild whitey! Group: Retired Admin Posts: 15,854 Joined: 7-January 03 From: Indy Member No.: 100 Region Association: None |
never had it. motor was a bus block. so, it doesn't sound like a valve adjustment is necessary? Should I check the screen at the tank? Is that a pain in the ass? I'm worried about taking the carbs apart the day before the car gets tech inspected for a prepaid no refund event.
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Bleyseng |
Apr 21 2004, 08:37 PM
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#8
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Aircooled Baby! Group: Members Posts: 13,035 Joined: 27-December 02 From: Seattle, Washington (for now) Member No.: 24 Region Association: Pacific Northwest |
Yes, check the valves and the FUEL FILTER.
I was just kidding cuz I hate carbs........ Geoff (IMG:style_emoticons/default/rocking nana.gif) |
seanery |
Apr 21 2004, 08:39 PM
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#9
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waiting to rebuild whitey! Group: Retired Admin Posts: 15,854 Joined: 7-January 03 From: Indy Member No.: 100 Region Association: None |
the thing about the valves, is I'm not sure I'd do it correctly. There was a thread earlier about a guy who did a valve job, but may not have done it right and the car wouldn't start. Finding TDC on #1 isn't something I'm totally confident in doing without supervision.
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Pnambic |
Apr 21 2004, 08:44 PM
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#10
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Honk if you like obscene gestures! Group: Members Posts: 914 Joined: 9-April 03 From: Atlanta, GA Member No.: 546 Region Association: South East States |
Heh, I'll supervise, but I don't know that I'd be able to tell you if you did it right or not.
I thought I read a pretty extensive walk-through at Pelican. It didn't seem too tough when I was reading it. Never done it though. Hell, you were taught by Bradholio, didn't take notes? (IMG:style_emoticons/default/smile.gif) |
seanery |
Apr 21 2004, 08:46 PM
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#11
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waiting to rebuild whitey! Group: Retired Admin Posts: 15,854 Joined: 7-January 03 From: Indy Member No.: 100 Region Association: None |
I can adjust em ok, if it's setup correctly. It's finding the right mark on the right cylinder that concerns me.
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lapuwali |
Apr 21 2004, 09:21 PM
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#12
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Not another one! Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743 |
The trick with making valve adjustments easy is you don't really HAVE to have the engine exactly at TDC. You simply need to ensure that the valve that's being adjusted isn't on the cam ramp.
On a flat four, this is very easy. Take both valve covers off, and look at the intake valve on cylinder 4. Turn the engine until it just starts to open (you'll see the rocker move). Now, the intake valve on cylinder 1 is timed 360 crank degrees away from the intake valve on cylinder 4, or 180 cam degrees, and they use the same cam lobe. So, when the intake on 4 is open, the intake on 1 must be off the lobe. Adjust 1, then reverse the process, turning the engine until 1 opens, then do 4. Repeat with 2 and 3. Exhaust valves are the same, as well. If you want to be extra precise, watch the rocker on the valve as you turn the engine, so it opens, then JUST starts to close (it will actually pause for a bit between opening and closing). You're now very close to TDC, and any error in valve lash will be under a thou, which is plenty good enough. If you're still running points, check them as well. Check the dwell and the timing. If you don't know when the points and condensor were last changed, replace them. They're cheap, and consumable. Ignition problems frequently masquerade as carburation problems. |
SirAndy |
Apr 21 2004, 09:43 PM
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#13
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Resident German Group: Admin Posts: 41,676 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
QUOTE(lapuwali @ Apr 21 2004, 05:59 PM) Not much detail there. What's "wierd"? Has it ever run correctly with these carbs? yupp. she ran fine when i drove her cross-country ... (IMG:style_emoticons/default/rolleyes.gif) Andy |
Brad Roberts |
Apr 22 2004, 12:57 AM
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#14
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914 Freak! Group: Members Posts: 19,148 Joined: 23-December 02 Member No.: 8 Region Association: None |
Sounds like junk in the carbs Sean. The fuel filter was new (crap from tank could have broke loose over time) but highly unlikely.
I doubt seriously it needs the valves adjusted again. I'm betting you havent put 1k miles on it since the last one. Make sure the floats are not sitcking. Pull the air cleaners and call me some time after noon my time and we can go over it on the phone. I have a car that I'll be busy with until noon. B |
Mark Henry |
Apr 22 2004, 06:41 AM
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#15
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
Disassembling and reassembling the carbs is not that hard. Make sure you have a nice clean work area and get a carb out. Face the idle bleed screws towards you and start taking it apart. As you go, lay the parts in order, so you remember which side they came out of. Count the how much the bleed screws are turned out. Turn them in counting (1 1/2 to 2 1/2 turns) make a note, then remove. Take all the jets out. You don't need a rebuild kit, unless all the gaskets are pooched, just reuse them.
Do not touch the throttle shafts or the screws with the lock nut on them. Do not over torque stuff (just snug) when putting it back together. About 2-3hrs for a novice, I can do both in about an hour. |
rhodyguy |
Apr 22 2004, 07:30 PM
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#16
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,090 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
sean, get the sycro out and see if the carbs are flowing the same.
kevin |
seanery |
Apr 22 2004, 08:01 PM
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#17
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waiting to rebuild whitey! Group: Retired Admin Posts: 15,854 Joined: 7-January 03 From: Indy Member No.: 100 Region Association: None |
don't have one. they were set up and haven't been touched, so they should still flow. Bradholio and I talked today, I agree with his diagnosis-crap in the carb somewhere. I tapped them with my plastic mallet today and let the car run for quite a while then rev'd it and held steady about 4k. I couldn't drive it as it was raining all day today and I have no wipers. I've got to get the rainex going and take the car to tech inspection tomorrow. That'll give me a good idea if the crap came out of the carbs or not. If not, I'll open them up tomorrow.
the good news is I put my koni yellows up front finally. |
rhodyguy |
Apr 23 2004, 07:23 AM
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#18
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,090 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
get one. when you have the idle jets out try blowing some air through idle circuit. i use the cans of compressed air. no snapping or poping? check the jam nuts on the threaded rods to make sure they are tight. does the problem dissapear at 3000 or so rpm?
kevin |
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