RavenTBK Posted January 12, 2005 Share Posted January 12, 2005 I figured I'd start again, but attack this from a different perspective.. Okay.. I've taken the Weber apart so many times, I feel I could rebuild one in my sleep. Today I had everything pulled from the top of the engine all the way down to the intake manifold. I inspected all the parts and connections and then put it back together. When it was time to crank it up, it ran nicely through the fast idle sequence, which has been set high at near 2500rpm on purpose. Once the choke opened up, it stumbles below 1500 revs, and refuses to idle period. Above 1500, it revs fine, and drives with all the power its always had. You release the go pedal, and when the revs fall below 1500, it stumbles then dies. Even with the idle screw turned all the way in, it wont run on its own. The new plugs I put in a couple days ago still look new.. no burning indicating lean-ness, and no excess amounts of carbon indicating rich. :-\ With all the times I've had the Weber apart, tweaking settings, I'm just about to rule it out even though I dont like how the fuel isnt atomizing properly in the venturi. Is there any documented cases where an ignition component fails that could cause these symptoms? Like something that could cause the dizzy not telling the coil to fire below 1500? Unlike you guys up in the great PNW, I dont have access to scores of Subies in the junkyards that I can swap various parts from to eventually find the culprit. I can only troubleshoot, and then try to locate a replacement for the failed part. :/ Or, on the third hand, should I just give up and drop the EA81 in favor for a junkyard EJ22? I have a feeling that troubleshooting the EFI would be just a whole other can of worms though. Quote Link to comment Share on other sites More sharing options...
MorganM Posted January 12, 2005 Share Posted January 12, 2005 EFI 2 WIN From what Snowman says it's not too hard to convert EA81 over to SPFI Plenty of Loyale's to scavange SPFI parts from. Vacume leak? Sorry I'm not into the whole carb thing.... Quote Link to comment Share on other sites More sharing options...
RavenTBK Posted January 12, 2005 Author Share Posted January 12, 2005 Plenty of Loyale's to scavange SPFI parts from.Not around here. I've found a grand total of three Loyales in the JYs within the last 6 months. Two were involved in fires, and the third was in the output pile from the crusher. I'm without emissions controls,so everything has been removed and plugged. Re-verified all plugs still in place this afternoon. Only two vacuum sources still exist.. the vac advance for the dizzy, and the brake booster. Its not idling high, just not idling at all. If a vac leak is really the cause, I need to pull the engine and look for a softball sized hole somewhere. Quote Link to comment Share on other sites More sharing options...
MorganM Posted January 12, 2005 Share Posted January 12, 2005 Not around here. I've found a grand total of three Loyales in the JYs within the last 6 months. Two were involved in fires, and the third was in the output pile from the crusher. I'm without emissions controls,so everything has been removed and plugged. Re-verified all plugs still in place this afternoon. Only two vacuum sources still exist.. the vac advance for the dizzy, and the brake booster. Its not idling high, just not idling at all. If a vac leak is really the cause, I need to pull the engine and look for a softball sized hole somewhere. Yeah it takes a big vacume leak to lower the idle. I know most raise the idle but I've had a large one (hose popped off PCV valve) and it wouldnt idle hardly at all. Hope you get it tracked down man. If not I can ship you all the Loyale parts you want Quote Link to comment Share on other sites More sharing options...
archemitis Posted January 12, 2005 Share Posted January 12, 2005 i had some simular symptoms, when my plunger in the top of my disty cap fell out, and just the spring was making the spark path complete. im not saying thats what it is, but it almost sounds like ignition to me. have you removed the things that say "do not remove" in the disty. your magnet could be cracked... just a guess. Quote Link to comment Share on other sites More sharing options...
Snowman Posted January 12, 2005 Share Posted January 12, 2005 My weber had similar issues. Just didn't seem to atomize the fuel right or something. What's the history of the carb? New? Rebuilt? JY? Quote Link to comment Share on other sites More sharing options...
RavenTBK Posted January 12, 2005 Author Share Posted January 12, 2005 After fiddling with about 15 different things, I've managed to get it to at least idle on its own for the most part. It coughs at around 11-1200 or so, but it will stay running for awhile without any user intervention. I think what did it is I stuck my finger behind and moved the EGR diaphragm a few times when the engine was off. Since its just still bolted in place and not hooked up at all, I didnt think to even check it, although rallyruss told me to check it in the old thread. Heh.. its the last part of the emissions system that hasnt been removed and blocked off. I figured since it wasnt hooked up, it would never open, and could never get anything caught in it. Amusing. Then again, it could've been a mix of that and the dozen or so other things I did under the hood today. The world may never know. Okay.. so now it idles, somewhat. Backing out the idle screw a bit to lower it down from the 11-1200 it coughs to stay alive at, it immediately stalls at 1000rpm. Since its more or less drivabale, I've run up to the parts store and ran half a can of seafoam through the carb throat, and the remaining half into the fuel tank. I only had 6 gals or so in it, so I used the 1oz:1gal average on the back of the can. Another interesting thing its doing is when I'm in decel mode in gear, it bucks and backfires through the carb. Accelerating, it runs like a scalded cat again.. even with the flat spots in the carb. I cant quite pick it out over the exhaust note, but I think I'm hearing the common "marbles in a tin can" noise.. pinging right? OTOH, I might just be hearing things. Could this and the decel backfiring be related? The timing hasnt been moved at all during this whole ordeal.. but who knows. At least it runs. Where should I go from here? ..other than to a competent repair shop for a complete tuneup? (cause there arent any Subie shops here.. only one VW shop) Quote Link to comment Share on other sites More sharing options...
RavenTBK Posted January 12, 2005 Author Share Posted January 12, 2005 My weber had similar issues. Just didn't seem to atomize the fuel right or something. What's the history of the carb? New? Rebuilt? JY? The history to me is unknown. It was on the Brat when I bought it from Mike D up in VA. The one thing I do know is that it looked/sounded right when I purchased a new air filter. I never needed to look again till it started acting up. Thats when I noticed the atomization issue.. I thought it was related to my short flight I took over that whoop. Hell.. it still could be. Quote Link to comment Share on other sites More sharing options...
subynut Posted January 13, 2005 Share Posted January 13, 2005 Just to rule out the timing issue, check it. Backfiring through the carby is a sign of too much advance (I think). I was having trouble with it mine backfireing though the carby while starting, but that was cause I was running 22 deg of advance. Backed it down to 18 and it dissappeared. If it was an EA82, I'd say a t-belt jumped a few teeth, but ea81....dunno. Do you got a vacume guage? Quote Link to comment Share on other sites More sharing options...
swiftt Posted January 13, 2005 Share Posted January 13, 2005 Yup. I agree. Sounds like timing is too far advanced. That causes pinging and backfiring like you describe. Quote Link to comment Share on other sites More sharing options...
RavenTBK Posted January 13, 2005 Author Share Posted January 13, 2005 I've got it running a whole lot better now that I tore open all the remaining emissions components and removed them. It makes sense that the remianing emissions components didnt like operating without all their buddies, so they acted out. So I killed em all! 100% emissions free. Now, moving on.. Okay.. this is a bit complex, so please bear with me. The symptoms that the Brat is exhibiting somewhat contridict themselves, and has me, my father, and several VW friends confused. Maybe it will make sense to one of you Weber heads out there. I've read that running lean is one of many possible sources that can cause the "rattle can" pinging. This is accepted as a fact. Keep this fact in mind as you read on. Now, its been proposed that my atomization issues are due to running excessively rich.. an idea that I standby as being possibly true. I say possibly true as theres no other explanation for it since theres nothing clogged anywhere. Here's the confusing part. It idles, rough. Only does so with the idle set screw all the way in. Moving your hand over the carb inlet (not blocking, but just "in the way") causes the idle to rise, and smooth out. Not rise and rev then bog, but simply rise to the level of the set screw and smooth out. This tells me that the carb is running excessively lean (which explains the pings above). BUT, the atomization issues say its overpressurized and running rich. HOWEVER, the carb bowl is vented to the atmosphere, and if it was "pressurized" with too much fuel in the bowl, fuel would rise up and dump out of the bowl vent. This fact tells me its not overpressurized. Fuel pressure at the carb inlet is 1.5psi, with spikes to 2psi when the needle closes. It cant be lean and rich at the same time. All logic says YES to both answers. -- Now here's a third option, which I dont believe should apply as this isnt an EFI vehicle. In EFI systems, if you dont have enough fuel pressure, the fuel wont atomize out of the injectors properly, and just drip.. rather similar to what it looks like in my carb now. This idea would tell me that its NOT getting enough fuel to build up behind the emusion tubes to atomize properly. Not enough fuel means lean, which kinda jives with the possibility above The only holdback is this ISNT an EFI system.. so that logic (to me) doesnt hold water. I'm caught in a catch 22 here. Anybody have any more thoughts? Or, am I just over analyzing this? Quote Link to comment Share on other sites More sharing options...
Snowman Posted January 14, 2005 Share Posted January 14, 2005 Have you checked the float level and travel? Maybe the fuel level is simply too low in the bowl. Quote Link to comment Share on other sites More sharing options...
RavenTBK Posted January 14, 2005 Author Share Posted January 14, 2005 Yep. Covered that last thread before I could get it running. I even did it again today. I've set it high, and low, and theres no change. :shrug: Quote Link to comment Share on other sites More sharing options...
RavenTBK Posted January 14, 2005 Author Share Posted January 14, 2005 Thats what makes this so damn confusing. Its pinging like its lean, but not atomizing like its rich. Attacking one problem at a time, the bowl level sits correctly at what the floats are set to.. either high, or low. So I know the needle/seat is fine (disassembled and inspected too), and the bowl isnt overfilling or underfilling. I'm running 140 mains, and 170pri/160sec air correctors. This combination worked fine before and yielded ~26mpg on a semi-regular basis. :shrug: Quote Link to comment Share on other sites More sharing options...
subynut Posted January 14, 2005 Share Posted January 14, 2005 Isn't there seperate circuits between the idle, primary and secondary? With the idle mixture screw all the way in, your running max lean which would explain the reason of the hand over carb mouth smoothing out the idle. Have you tried this site: http://homepage.powerup.com.au/~camncath/retrofitting_the_weber_dgav_32.htm Quote Link to comment Share on other sites More sharing options...
RavenTBK Posted January 14, 2005 Author Share Posted January 14, 2005 Yeah I have seen that site. Thats what got me started with the troubleshooting awhile back. As for the idle set screw above, I'm referring to the idle set screw, not the idle mixture screw. Quote Link to comment Share on other sites More sharing options...
subynut Posted January 14, 2005 Share Posted January 14, 2005 does it make any differance if U move the mixture screw? hummm gonna hafto do a few dounuts and think on this one........... Quote Link to comment Share on other sites More sharing options...
RavenTBK Posted January 14, 2005 Author Share Posted January 14, 2005 I didnt really notice any. I turned it one way, it stumbled. Other way, it stumbled. Just to be sure, someone point out to me which screw is the idle mixture adjustment? I'd feel like a ******* if I was twisting the wrong screw. Quote Link to comment Share on other sites More sharing options...
monstaru Posted January 14, 2005 Share Posted January 14, 2005 side note, when you get a chance can you tell me the rundown of getting rid of your emissions goodies? please.thanks, brian Quote Link to comment Share on other sites More sharing options...
subynut Posted January 14, 2005 Share Posted January 14, 2005 Sounds like the idle mixture is right on. Idle speed screw directly pushes on the throttle linkage. Idle mixture goes into the front passenger corner on the carb body. Below (I think) the ditsy vac. advance port on the carb. Quote Link to comment Share on other sites More sharing options...
swiftt Posted January 14, 2005 Share Posted January 14, 2005 Turn the mixture adjuster in until it begins to run rough then turn it out 'til it runs rough. Count the turns between these two points and set the mixture screw in the middle of those to points, plus a quarter turn toward lean. Example: If there are 3 turns between rough idle at lean and rough idle at rich, then turn the screw 1 1/2 + 1/4 =1 3/4 turn in from rich or 1 1/2 - 1/4 =1 1/4 turn out from lean. Also important to make sure the choke is operating properly. I think I remember you saying you checked this but never-the-less... The choke plates should be closed when your car is cold and should open up completely as the car warms. If one or the other is not happening, the cause needs to be determined. I still don't see where you double checked the timing. Very important to make sure it's correct before fiddling with everything else. If you have a solid lifter engine, you should also adjust the valves to the prescribed clearances. If you just want to bring it to Portland, I'll fix it up for you. Quote Link to comment Share on other sites More sharing options...
RavenTBK Posted January 14, 2005 Author Share Posted January 14, 2005 Portland. Oh yeah.. lemme fire up my Star Trek official transporter device. Hehe.. I do believe I'm just gonna break down and take it up to one of the shops I used to frequent. He used to do a lot of work on carbs.. maybe I can get a rebuild and tuning done on the cheap. This mess is beyond me. Quote Link to comment Share on other sites More sharing options...
coloradosubarules Posted January 14, 2005 Share Posted January 14, 2005 Someone please help Raven. He needs to put his face (and Brat) in the place tommorow. The honda will do in a pinch though. Look on ebay motors in the parts cars part. There is a guy with an 85 Roo tht he is asking 200 bucks for. Might want to check it out. Hope to see ya tommorow. Check the meet n greet post. I put a link up for the weather in winter parl tommorow. Cool but no rain. Quote Link to comment Share on other sites More sharing options...
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