subyrally Posted May 18, 2008 Author Share Posted May 18, 2008 When that carb base gasket blew on my '86 BRAT last November, it wouldn't fire up after repairs until I swapped in new sparkplugs. May want to try that. the plugs are brand new, have 0 miles on em/ i took em out the other day, mnade sure they were clean and dry. pretty easy job since there was no carbon or anything to trap and hold "crud" Quote Link to comment Share on other sites More sharing options...
subyrally Posted May 22, 2008 Author Share Posted May 22, 2008 so yeah, i got the brat to start last night, but it had an air leak from one of the intake manifold bolts being loose. it would idle at about 2k and stall if i pressed the gas and rev if i blocked the carb. i fixed the loose bolt last night before calling it a night. today affter work, i got out there and tried starting it again, it took a bit of cranking, but it finally kicked over. but ran really poorly and wouldnt stay running. i adjusted the idle screw and turned hte distributor, it started trying to run after that. but it would idle at about 600 for a few seconds and then rev to about 4-5k and then just die. so far, no adjustments ive made have fixed that. i am running out of ideas. especially since i still know next to nothing about tuning carburetors. Quote Link to comment Share on other sites More sharing options...
subyrally Posted May 25, 2008 Author Share Posted May 25, 2008 well, the brat runs, kinda. i got it to idle around 1000-1200rpm and it will actually rev when i give it some gas, but there is a bit of a hesitation from when i press the pedal and the engine actually reving. i also pulled the hose for the vac advance off of the hard line and there was absolutely no difference in how the car was running. im guessing that its gummed up or just buggered. i also think that i need to get the carb tuned a bit better than what ive done with it. im not sure what needs done now, i is running closer to where it should, but its running rough. i think the fact that one of the plugs gotcracked by my friend when he was taking it out. i think that the mixture and idle both need to be set properly. Quote Link to comment Share on other sites More sharing options...
mountaingoatgruff Posted May 25, 2008 Share Posted May 25, 2008 well, the brat runs, kinda. i got it to idle around 1000-1200rpm and it will actually rev when i give it some gas, but there is a bit of a hesitation from when i press the pedal and the engine actually reving. i also pulled the hose for the vac advance off of the hard line and there was absolutely no difference in how the car was running. im guessing that its gummed up or just buggered. i also think that i need to get the carb tuned a bit better than what ive done with it. im not sure what needs done now, i is running closer to where it should, but its running rough. i think the fact that one of the plugs gotcracked by my friend when he was taking it out. i think that the mixture and idle both need to be set properly. check the advance diapragm of the dist by putting some fresh rubber hose on it then seeing of it moves as you apply vac. if it won't move then its probably toast. also, have you made sure there's no vac leaks elsewhere? Quote Link to comment Share on other sites More sharing options...
subyrally Posted May 25, 2008 Author Share Posted May 25, 2008 check the advance diapragm of the dist by putting some fresh rubber hose on it then seeing of it moves as you apply vac. if it won't move then its probably toast. also, have you made sure there's no vac leaks elsewhere? i couldnt find anymore, but then again, its hard to sometimes when there are so many vac lines. if the vac advance is toast, what can ido about it? Quote Link to comment Share on other sites More sharing options...
Gloyale Posted May 25, 2008 Share Posted May 25, 2008 well, the brat runs, kinda. i got it to idle around 1000-1200rpm and it will actually rev when i give it some gas, but there is a bit of a hesitation from when i press the pedal and the engine actually reving. i also pulled the hose for the vac advance off of the hard line and there was absolutely no difference in how the car was running. im guessing that its gummed up or just buggered. i also think that i need to get the carb tuned a bit better than what ive done with it. im not sure what needs done now, i is running closer to where it should, but its running rough. i think the fact that one of the plugs gotcracked by my friend when he was taking it out. i think that the mixture and idle both need to be set properly. Cracked plug will let the spark *arc* out to the side of the head. Replace that with NGK plug immediately. Use a hand held Vac Pump to test the Vaccuum advance. If it is shot, get a new disty, or send you're vac advance unit to the Philbin group http://www.philbingroup.com/ Also are the slow and primary bleed ports plugged off? T-d into intake? open? Quote Link to comment Share on other sites More sharing options...
subyrally Posted May 25, 2008 Author Share Posted May 25, 2008 Cracked plug will let the spark *arc* out to the side of the head. Replace that with NGK plug immediately. Use a hand held Vac Pump to test the Vaccuum advance. If it is shot, get a new disty, or send you're vac advance unit to the Philbin group http://www.philbingroup.com/ Also are the slow and primary bleed ports plugged off? T-d into intake? open? ngk is the only plugs that i use, dont have a vac pump yet, but i might go buy one if i cant get ahold of one. and as far as the last question goes, huh? Quote Link to comment Share on other sites More sharing options...
mountaingoatgruff Posted May 25, 2008 Share Posted May 25, 2008 ngk is the only plugs that i use, dont have a vac pump yet, but i might go buy one if i cant get ahold of one. and as far as the last question goes, huh? you only need to use a vac pump to check the diaphragm if you're iffy about sucking on the hose, but that's how i check them. it doesn't tell you how much pressure is required to actuate the thing but it sure tells you if its ruptured and that's the likely scenario. if you can suck on the line and verify the diaphragm won't move its ruptured and needs to be fixed/replaced. i have a good and a bad one on a shelf in the garage and i can move the good one, the bad one is obvious. you should NEVER run broken plugs but i figured that was common sense to most folks that know what kinda plugs we're talking about and it doesn't sound like you were running it anyhow. dumb question of the day: has anyone ever made an adapter to use an older side-by-side 2bbl carb on an ea81 engine? like a simple, reliable, cheap, old 3stud stromberg 2bbl or something? or maybe a big ol' holley 1bbl? i imagine you could put a holley 1bbl on an spfi intake with a simple adapter and have a simple reliable carb on a better manifold too. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted May 25, 2008 Share Posted May 25, 2008 dumb question of the day:has anyone ever made an adapter to use an older side-by-side 2bbl carb on an ea81 engine? like a simple, reliable, cheap, old 3stud stromberg 2bbl or something? or maybe a big ol' holley 1bbl? i imagine you could put a holley 1bbl on an spfi intake with a simple adapter and have a simple reliable carb on a better manifold too. It's been done - the problem with the SPFI manifold is that the base of the TBI isn't level. It has to be seriously modified to make anything bolt up to it. The best way to go if you are into that much fabrication is to just make two-peice adaptors to sit directly on the heads and run seperate carbs on each head. Drill press and a die grinder...... GD Quote Link to comment Share on other sites More sharing options...
subyrally Posted May 26, 2008 Author Share Posted May 26, 2008 i know about hte plug thing, granted, since i didnt have anyhing else to put in it at the time, i ran it for al itte bit with the cracked plug. i got a full set of ngk vpower plugs yesterday and i need to order another ngk iridium plug to replace the broken one. i plan on using the iridium plugs again once i get everything runnign right. if i can get out to work on the car tomarrow, ill try to test the diaphram if i can. it running though, granted, its rough and there is still a noticeable hesitation. i am going to try resetting the mixture and idle tomarrow, i think its runnig a bit rich as it is, which ive heard could be part of the hesitation. ill find out tomarrow after i finish making the waterfall/pond thingy for my mom, lol. you only need to use a vac pump to check the diaphragm if you're iffy about sucking on the hose, but that's how i check them. it doesn't tell you how much pressure is required to actuate the thing but it sure tells you if its ruptured and that's the likely scenario. if you can suck on the line and verify the diaphragm won't move its ruptured and needs to be fixed/replaced. i have a good and a bad one on a shelf in the garage and i can move the good one, the bad one is obvious. you should NEVER run broken plugs but i figured that was common sense to most folks that know what kinda plugs we're talking about and it doesn't sound like you were running it anyhow. dumb question of the day: has anyone ever made an adapter to use an older side-by-side 2bbl carb on an ea81 engine? like a simple, reliable, cheap, old 3stud stromberg 2bbl or something? or maybe a big ol' holley 1bbl? i imagine you could put a holley 1bbl on an spfi intake with a simple adapter and have a simple reliable carb on a better manifold too. Quote Link to comment Share on other sites More sharing options...
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