hey everyone, I've heard about putting atf in your carburetor or gas tank to clean the motor out. I guess like what sea-foam does. I'd be doing it strictly to my early 70s sbc. It's running a little weird, when I give it gas it basically like coughs. Now my questions are the following: 1. Is it safe for my engine? 2. How much do I pour into my older holley carb? 3. Just straight ATF, no water(heard someone say they used water with atf...I was confused)? 4. Let it idle, mid rpm, or High rpms? Everywhere I look, people say different stuff like "don't do that it messes up your motor" while others say they've been doing it for the last 30 years... Heres the steps If I were to go do it. Pour a small amount directly in carb. while idling, then start revving it a little until the smoke is all gone. Thanks everyone
Won't hurt you engine any, speed up the idle and let fly. of course you could try and find out what is wrong with your engine first. A few thing to look at, is your accelerator pump working? When was the last time it got a set of points? What are your plugs like? tell you a story, in the later '80s a friend takes his son's '65 mustang to one of those diagnostic lanes because it had a stumble. They do whatever it is that they do and tell him it has some burnt valves and needs at the very least a valve job and possible a new head. I happened by just as he is getting back and he is whining like a little girl about what it is going to cost him to get a valve job done. So I say when was it last tunned up, he said it had new plugs and wires. So I say how about the points are they OK? He says what are points? So i open the distributer and sure as I am alive the points are fried. Off to NAPA I go and pick up a set of points for 4 bucks. Took me all of 20 minutes to install them, I didn't have a feeler gage with me so I gapped them with a match book. We lit it off and back to the diagnostic lane we went. The checked it out again and it tested perfect. No problems whatsoever. The fella wanted to know how we got the head changed out so quick. he said that there was no problem with the head, it just needed a set of points. He said what are those? Always tune it before you do anything else to it.
Yeah, what Porknbeaner said, won't hurt anything but that ain't gonna fix yer problem. Sounds more like you've got carb or tuning problems.
Well the carb. was rebuild last year. I've also replaced the points, the cap, pvc valve, fuel filters, and recently the accelerator pump It's getting really annoying,but when I'm in neutral and rev it up it sounds GREAT but in drive its like choking on a bone, some times it clears up sometimes not. Recently I cleaned all the plugs on a wire wheel and gapped them all. They are a year old too. I just want to be able to accelerate with out all this hesitation. I was hoping the ATF trick might "clean" it's sinuses out. Any other ideas?
Well I don't think that running trans fluid through the carb is the answer,Have you checked to see if your getting a good shot of gas from the accelerator pump? have you checked the timing?does it have points? have you checked the dwell?is the timing chain good?are the valves adjusted properly?is the vacuum advance working or the advance weights working?do you have a vacuum leak?? There is nothing you are going to pour in your tank or feed down your carb that will cure a driveability concern. what your doing is what they used to do to break up carbon on the valve's and piston's year's ago,but if you ask me I would'nt because that little pieces of carbon get between the piston's and cylinders and its just like sandpaper!!! just my 2 cents
Well I just put a little ATF down the carb, then ran it and it was good but then it did it again. It does this same thing when I wash it, but worse, like somethings getting wet. But I know nothing wet because I haven't wash it lately. How do I find a vacuum leak? The timing,valves,points are good.
Boy oh boy, that sounds like a lot of work! ATF in the carb would be easier- Not going to fix any of that stuff. Might clean some gunk and build up off the valves but your cough isn't caused from that.
Have to be careful about pouring the ATF while the engine is running. Too much at one time can hydroloc the engine & bend a rod. We used to have those Ford F model pickups come in for the fuel injector recall & a bunch came in with a bent rod from too much fuel. Like my old man used to say "theres nothing in a can that gonna fix a car"
Yup, This is like trying to cure cancer with Aspirin. Check the basics first. When I get an old car here's how I tackle it: 1) Check compression. If compression is good, the engine should run at least reasonably well. If it fails this test, fix or replace engine. 2) Check timing chain. This is easier than ya think.. using a breaker bar, watch if the engine crank pulley moves the distributor rotor without play, if it moves a little in either direction before the rotor moves, then you have a worn timing chain. This means timing all out to sea and the engine isn't going to run right, period. If it fails this test, change timing chain and gears. OK, so now we know the engine itself is probably healthy. Now we need to check the valve lash. Check and adjust as needed. Now the engine itself should be tuned mechanically. 3) Ignition. I always assume that the cap, rotor, plugs, wires, coil, points and condensor are bad. Period. If you've owned the car, check these first. Then set timing. 4) Fuel. with ignition disconnected test the fuel pump. You DID make sure the fuel lines are recent, you used fuel injection hose and you cleaned the fuel pump bowl and put in a new fuel filter, right? If all checks out.. move to the carb. Grab factory manual, set carb. Fiddle with carb, see how car runs. If car is unknown, remove carb, check for throttle shaft wear in carb body, test float to make sure it doesn't sink in a bowl of water, make sure it's got new gaskets, make sure the jets aren't clogged, etc. Start with the absolute basics... I have yet to see any miracle in a can really fix a mechanical problem. I've seen Marvel Mystery oil free up sticking rings and lifters, but none of this stuff is going to fix a real problem.
Before you do any of this...pull the air cleaner...look down the primany (front) barrels, & slowly, continuously open the throttle. You should have a good strong stream of fuel squirting out from the accelerator pump. If not...most likely your problem..possibly in combination w/timing
All good advice so far. If it idles good, it probably doesn't have a vacuum leak. If it sounds kinda "growly" on deceleration...kinda quick backfires in succession...it's probably got a stretched timing chanin. rid14's method of turning the crank a little bit both ways to see if the rotor turns with it with no slop will confirm it. And when checking the accelerator-pump, make sure you have "squirt" as soon as the throttle is moved. But if after you've checked all this and the other things everybody has mentioned...check the cam. Worn cam lobes will make an engine sneeze out the carb. Just in case this is happening, be sure you're not lookin' down the carb when you goose the throttle...you'll get a face full of flames. To actually check for worn cam lobes, you'd have to remove the valve-covers, run the engine, and see that all the rockers are lifting the same amount. Only thing is, you mentioned that the symptom doesn't happen all the time, and it runs good until going' down the road. And that it seems worse when you wash it. Could be the wire from the coil to the distributor is bared and touching something, and it only does it when the wire is being buffeted from rushing air as you go down the road. But you also said it clears up sometimes. An intermittant problem is very often due to dirt in the carb bowl. It's fine, then when you run it a bit, the dirt clogs the jets. After it sits for a while, the dirt falls away from the jets, then it runs fine again, until the dirt gets sucked into the jets again. Or possibly a clogged gas-tank outlet, line, or fuel-pump. Good luck.
A bad timing chain won't generally cause a cough, it will just be down on power, and could have very retarded timing, which will cause a cough.. I would first look and make sure the accelerator pump is giving a good healthy quirt. I would then check the timing. and make sure you have the vac hose hooked up right. Go for at least 12° initial with the vac advance line blocked to start. If it helps, add a little more as long as it doesn't ping. And pouring ATF or Sea Foam, or marvel Mystery down the throat of a running carb doesn't clean the carb at all - it goes right through the venturies and into the motor
We used to inject atf in the carb of our junk parade vehicle to make it smoke. We would put the atf in the windshield fluid reservoir, run the line into the carb and when we wanted it to smoke in front of the crowd, we hit the wiper wash button.
pouring ATF into your engine was something i have done for years to clean carbon off valves and have had great success doing it. I do it at night cause it smokes like hell! High idle and feed that dude a full quart and your idle will smooth out. I remember the guy next to my grand parents house and he always used water until he busted a head.
take a can of carb cleaner put the little tube on the nozzle,spray around the carb and intake manafold,or you can use water too,but carb cleaner work's the best look for an rpm's to raise up
I actually had to do something like this one time and it saved my ass! My wife's 427 'vette was in storage for a few months, and when we fired it up to drive it, the motor had a nasty knock that you could actually feel at idle. It had good oil pressure, but it sure sounded like a crank or rod to me, so we parked it and I was going to yank the motor for a rebuild the following week. A buddy of my Dad's asked me if it had domed pistons and I told him I thought it did, since it was original and had 10.5:1 compression. Then he told me that happened to him once and he found out that a chunk of carbon had flipped over from one side of the dome to another, and since there wasn't enough clearance, it developed a knock, the only difference was that he actually pulled his motor to find it. So out came the ATF since I had nothing to lose. Worked like a charm as soon as the smoke cleared!
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