BilletMan
Makes Chips and Rapid Conversaion
- Joined
- Dec 29, 2001
- Messages
- 18,964
This guy has the right idea:
whos an older sbc carb motor expert
- Thread starter Your Car Is Slow
- Start date
Wretch
amazingly graceful
I don't know BilletMan, that is one of those electronic bits that either works of doesn't.
I wondered aloud about it even being the right one installed, earlier, since there are different curve values between SBC engines apparently depending on the vehicle/use.
ECM aka engine control module.
Probably cheaper to replace the whole thing as mentioned.
I wondered aloud about it even being the right one installed, earlier, since there are different curve values between SBC engines apparently depending on the vehicle/use.
ECM aka engine control module.
Probably cheaper to replace the whole thing as mentioned.
OP
OP
Your Car Is Slow
BAMF+
no cats
Vicious_Cycle
BAMF+
What's the latest?
Post a pic of the ride!
OP
OP
Your Car Is Slow
BAMF+
baby didnt really let me get out to the garage and fuck with it yesterday..and i spent this afternoon working on her new playhouse!
was hoping to get out there tonight, but its not looking good there either...will update thread when i get the carb apart! (with pics)
was hoping to get out there tonight, but its not looking good there either...will update thread when i get the carb apart! (with pics)
OP
OP
Your Car Is Slow
BAMF+
here was most recent view..
Matt Sterbator
BAMF
The problem is that it's not an LS, lolz
OP
OP
Your Car Is Slow
BAMF+
yea..i really need to stop reading c10/ls swap threads!
Matt Sterbator
BAMF
With all the LS stuff around there I'm surprised one hasn't just fallen into the engine bay!
Wretch
amazingly graceful
LS swaps ain't cheap and with all the SB laying around, it becomes difficult to justify the more expensive route unless you're going to use it to win at the drag strip.
OP
OP
Your Car Is Slow
BAMF+
what? ls swaps are retarded cheap these days. under 1500 easy.
Wretch
amazingly graceful
Really?
I must have been out of the loop too loong then.
I seem to recall it being around $3500.00 the last time I looked and that was with using used parts.
I have a G body I'd love to put an LS in but, it would need some serious suspension/brake upgrades to make it a reasonable daily driver.
I must have been out of the loop too loong then.
I seem to recall it being around $3500.00 the last time I looked and that was with using used parts.
I have a G body I'd love to put an LS in but, it would need some serious suspension/brake upgrades to make it a reasonable daily driver.
OP
OP
Your Car Is Slow
BAMF+
shit no...you can find a yanked out 5.3ls motor from any one of millions of 2000-2008 or so chevy trucks out of any junkyard...tons of folks even make a business selling them yanked out complete with ECM.
anywhere from 600-900 bucks for a 5.3 few sheckles more for a 6.0. (iron ones anyway)
add in a 4l60 trans for another few hundred and its not uncommon at all to have a full swap for around a grand. heck ive even seen complete tahoes and yukons and sierras that have been wrecked or salvaged for under 2k with those drivetrains in them.
anywhere from 600-900 bucks for a 5.3 few sheckles more for a 6.0. (iron ones anyway)
add in a 4l60 trans for another few hundred and its not uncommon at all to have a full swap for around a grand. heck ive even seen complete tahoes and yukons and sierras that have been wrecked or salvaged for under 2k with those drivetrains in them.
OP
OP
Your Car Is Slow
BAMF+
i always keep on the lookout for a decent deal to snag up...this truck will certainly get an ls upgrade (if not just for the 4l60 auto trans to upgrade from the th350 in it now).
but it just wasnt worth yanking out a good running sbc just to upgrade to an LS for a truck that drives under 1000 miles a year or so!
but it just wasnt worth yanking out a good running sbc just to upgrade to an LS for a truck that drives under 1000 miles a year or so!
OP
OP
Your Car Is Slow
BAMF+
not convinced it was the source of the problem, but it definitely benefited from a nice carb cleaning. first shot after removing the cover.
good bit of stuff gunked up at the bottom of the bowls, but nothing was clogging the ports...even shooting air into all of them and the horns after removing and cleaning those... and nothing significant came out...just a nice layer of buildup shown here.
who knows...maybe this could be the cause of all my issues, but i kind of expected alot more bullshit than that to clog up the carb enough to drag the motor down to what ive been experiencing lately.
will take another test drive tomorrow.
good bit of stuff gunked up at the bottom of the bowls, but nothing was clogging the ports...even shooting air into all of them and the horns after removing and cleaning those... and nothing significant came out...just a nice layer of buildup shown here.
who knows...maybe this could be the cause of all my issues, but i kind of expected alot more bullshit than that to clog up the carb enough to drag the motor down to what ive been experiencing lately.
will take another test drive tomorrow.
OP
OP
Your Car Is Slow
BAMF+
ps..no parts leftover after putting it back together...this is a good sign!
pimpslayer
BAMF+
If you go for a ride expecting it to drag down after it gets hot, have someone standing by when you get back to the garage.
Have them help you keep it running while one of you dribble a little bit of gasoline down the throat of the carb. If it doesn't pick up and run better, you have an electrical problem.
Have them help you keep it running while one of you dribble a little bit of gasoline down the throat of the carb. If it doesn't pick up and run better, you have an electrical problem.
OP
OP
Your Car Is Slow
BAMF+
yea im also going to just run a new line from the ignition switch to the diz just for peace of mind.
Wretch
amazingly graceful
Most driveability issues I've run across are multiple issues of a little shit here and there going wrong.
That carburetor is/was nasty inside with varnish.
You might check any rubber lines from the tank to see if the ethanol broke them down enough for them to collapse.
Some short pieces from near the tank connecting to the rigid lines too, if I recall correctly.
Ask for specific new fuel line that'll be resistent to breaking down.
That carburetor is/was nasty inside with varnish.
You might check any rubber lines from the tank to see if the ethanol broke them down enough for them to collapse.
Some short pieces from near the tank connecting to the rigid lines too, if I recall correctly.
Ask for specific new fuel line that'll be resistent to breaking down.
OP
OP
Your Car Is Slow
BAMF+
id already replaced the rubber in the system (as well as the fuel pump) with modern stuff...the og hard lines are still there though.
really need to find a tank to put under the bed so i can get it out of the cab...never much liked sitting on 10 gallons of gas!
really need to find a tank to put under the bed so i can get it out of the cab...never much liked sitting on 10 gallons of gas!
Vicious_Cycle
BAMF+
Can you see if there's shit in the bottom of the tank? If you have a pick up screen that's picking up shit the whole time it's running, that obviously would make it not want to run after a while. Shut the truck off, some of the shit drops off the screen, back to the bottom of the tank... truck runs again.
Wretch
amazingly graceful
VC is right, clogged sock on the pickup would be a game killer as far as staying running goes.
OP
OP
Your Car Is Slow
BAMF+
not a bad suggestion for sure! def cant see the bottom of the tank but can likely pull out the pickup tube.
im not sure its anything more than a straight tube...id be shocked if it has any sort of filter on the end of it.
im not sure its anything more than a straight tube...id be shocked if it has any sort of filter on the end of it.
Bandit Man
BAMF
Hit the distributor with a hair dryer before you run it and see if the problem is there from the get go. You are better off with a good used dizzy than that chink POS
BigGar
high on placebo
I'm feeling a coil / distributor issue that doesn't show up until it gets hot. Possibly a fuel pump that's working just good enough until the diaphragm warms up a bit and loses efficiency, but you say there's plenty of fuel in the clear filter, so I'm doubting that. Edelbrock carburetors are pretty trouble free, so I don't think that's your issue, unless you're getting a vapor-lock situation going, which is also a possibility. Might need an insulating spacer between carb and manifold and (or) and electric fuel pump. It seems vapor lockish or sparkish.
bowtie
BAMF+
jhinderliter
BAMF
👌
I traded a project car I lost interest in for a junk GMC pickup with a 5.3 a year or two ago. My intention was a new engine for my '94 C1500 stepside, which has a 305. The guy I got the truck from had a sweet, late 80's Cutlass 442 with a 6.0 swap. He was telling me how easy it was, but he works in a fabrication/hot rod shop, so we probably have different definitions of "easy." I also want to keep the manual trans, which looks like a pain in the ass with an auto trans donor. Anyway, two weeks ago, a guy drove by and saw the GMC sitting in the weeds off my parking lot, and made an offer more than I had in the whole shebang, so that ended that dilemma for the immediate future. The 305's got about 190K on it, but still runs great, doesn't smoke or burn oil or anything. I only drive it 1200 miles or so a summer. Just think it might be more fun with a bit more snap.
OP
OP
Your Car Is Slow
BAMF+
yea its got one of those plastic spacer rings on the intake (also an edelbrock performer intake)
ill get it sorted eventually...however an 18mo old kid really limits the time I get to fuck off in the garage!
ill get it sorted eventually...however an 18mo old kid really limits the time I get to fuck off in the garage!
OP
OP
Your Car Is Slow
BAMF+
I traded a project car I lost interest in for a junk GMC pickup with a 5.3 a year or two ago. My intention was a new engine for my '94 C1500 stepside, which has a 305. The guy I got the truck from had a sweet, late 80's Cutlass 442 with a 6.0 swap. He was telling me how easy it was, but he works in a fabrication/hot rod shop, so we probably have different definitions of "easy." I also want to keep the manual trans, which looks like a pain in the ass with an auto trans donor. Anyway, two weeks ago, a guy drove by and saw the GMC sitting in the weeds off my parking lot, and made an offer more than I had in the whole shebang, so that ended that dilemma for the immediate future. The 305's got about 190K on it, but still runs great, doesn't smoke or burn oil or anything. I only drive it 1200 miles or so a summer. Just think it might be more fun with a bit more snap.
BigGar
high on placebo
If it's already got a spacer ring it's probably not that. I had a clients' old Pontiac that had a weak mechanical fuel pump. I'd never seen that before as they usually either work or don't work. This one would pump o.k. when cold, then lose it's mojo as the engine heated up. Then it would just barely keep up if you were cruising slowly but give it any gas and the float bowls just didn't have enough in them to get you up a hill! I had a helluva time figuring that one out. At least it's got a brand new HEI ignition in it that made absolutely no difference!
Master-Cylinder
Duck Loving Curmudgeon and Legendary Race Wrench
Didn't those old mechanical small block Chevy fuel pump develop a problem with the arm or the spring on it? Seems like it was a common issue back in the day.
BigGar
high on placebo
I'm not sure M/C. I just know that when I finally just replaced the one on the Pontiac out of sheer exasperation, the problems went away.
OP
OP
Your Car Is Slow
BAMF+
fuel pump is also brand new (swapped it when i did the cam since it had to come off anyway).
it certainly appears to provide plenty of punch visible via the filter. i cant imagine those things were meant for more than single digit psi either way.
im hoping for my next test drive im able to hop out and have someone keep it running while i can take a look under the hood and shoot some gas or carb cleaner down into it. its response to that should eliminate at least half the possibilities.
it certainly appears to provide plenty of punch visible via the filter. i cant imagine those things were meant for more than single digit psi either way.
im hoping for my next test drive im able to hop out and have someone keep it running while i can take a look under the hood and shoot some gas or carb cleaner down into it. its response to that should eliminate at least half the possibilities.
BilletMan
Makes Chips and Rapid Conversaion
- Joined
- Dec 29, 2001
- Messages
- 18,964
Ignition problem, module in the distributor...heat sensitive...
BigGar
high on placebo
OP
OP
Your Car Is Slow
BAMF+
finally got out to try to start it, damn thing starts right up and shoots to nearly redline even without my foot on the gas.
thats super fun...clearly i did something wrong in reassembly!
thats super fun...clearly i did something wrong in reassembly!
BigGar
high on placebo
You're going to have to do better than that. Did you take something apart and put something back together? Is it fixed now, or not? If it's revving up high on it's own right after startup, that sounds like a fuel problem. Choke? Faaaaaack. . . I thought it was dying, not it's revving...
OP
OP
Your Car Is Slow
BAMF+
id rebuilt the carb a few nights ago (well, i say rebuilt...more like took it apart and cleaned it all out...pics above).
the truck is obnoxiously loud so i try to refrain from running it late at night and with a sick kiddo ive not had any time at all to go fuck with it since I put the carb back on.
today i was out there doing some woodworking items and decided to see if it would fire up...and it did. but i had to immediately shut it off due to it not actually idling but instead running up near 4k rpm with my foot not on the throttle.
did a few cursory looks, no vaccum lines are loose or disconnected, choke is working as it should (engages/disengages the flapper as normal)...throttle cable looks to be fine, its certainly not stuck open and has normal free range of movement and return spring works as it should also.
im not terribly sure what i could have done to cause something like this, its not like these old carters are terribly complex! if it was just a slightly high idle id start messing with the low/high speed adjusters...but the fact that it shoots up to 4k leads me to believe something more significant is off.
the truck is obnoxiously loud so i try to refrain from running it late at night and with a sick kiddo ive not had any time at all to go fuck with it since I put the carb back on.
today i was out there doing some woodworking items and decided to see if it would fire up...and it did. but i had to immediately shut it off due to it not actually idling but instead running up near 4k rpm with my foot not on the throttle.
did a few cursory looks, no vaccum lines are loose or disconnected, choke is working as it should (engages/disengages the flapper as normal)...throttle cable looks to be fine, its certainly not stuck open and has normal free range of movement and return spring works as it should also.
im not terribly sure what i could have done to cause something like this, its not like these old carters are terribly complex! if it was just a slightly high idle id start messing with the low/high speed adjusters...but the fact that it shoots up to 4k leads me to believe something more significant is off.
BigGar
high on placebo
Sounds like the butterfly must be partially open. Maybe it's up on a choke cam or the fast idle is set way too high?
OP
OP
Your Car Is Slow
BAMF+
yea, its def getting air from somewhere...just dont see anything obvious at the moment.
i cant even fathom the fast idle adjustment would let it rev as high as it does.
i cant even fathom the fast idle adjustment would let it rev as high as it does.
Wretch
amazingly graceful
The linkage is closed and it's revving to 4K?
You have the gaskets properly in place under it?
Accelerator pump is working, squirting fuel?
Secondaries aren't still open when engine is off?
The last two is where I'd start looking.
You have the gaskets properly in place under it?
Accelerator pump is working, squirting fuel?
Secondaries aren't still open when engine is off?
The last two is where I'd start looking.
Master-Cylinder
Duck Loving Curmudgeon and Legendary Race Wrench
More than a few times after I've cleaned a set of carbs, I've had to crank the idle speed screw out a few turns because it now has clean jets and passages. Over the years, the things start to run a bit off, and the guy just keeps cranking the idle screw in to keep it idling, and then it gets to the point where it doesn't run.
pimpslayer
BAMF+
Oh yeah. Always fun having a big Jap 4 cylinder go to the redline after just a tap on the starter button. 
Wakes up everybody in the Service Department...
.
Wakes up everybody in the Service Department...
.
bowtie
BAMF+
so now you.ve fucked up a reasonably easy task, and you have 2 issues, congrats ..
OP
OP
Your Car Is Slow
BAMF+
aint projects fun???
bowtie
BAMF+
OP
OP
Your Car Is Slow
BAMF+
well sho nuff it was the idle adjustment screw!
disconnected the throttle cable, backed the adjuster all the way out and cranked it up...idled great! Id have never thought that would have as much play in it to crank an idle up that high!
reattached throttle and let it heat up for at least 20min and took a short drive, all seems well! will try a longer drive later this evening.
disconnected the throttle cable, backed the adjuster all the way out and cranked it up...idled great! Id have never thought that would have as much play in it to crank an idle up that high!
reattached throttle and let it heat up for at least 20min and took a short drive, all seems well! will try a longer drive later this evening.
Master-Cylinder
Duck Loving Curmudgeon and Legendary Race Wrench
If you had to crank the idle speed screw way out, and it also runs better, sounds like you did the job right. But, a longer test drive will tell the tale.