57 inline 6 235..Popping,Sputtering

OK..ive gone threw all the valves 3 times..Start it up..sounds great..runs strong..then after 5 min..starts to miss and pop.. I rev it sounds OK..let it sit 15 seconds Rev again..POP..backfire...from the carb..Stop the motor..check the Plugs...BLACK..soot..ashy.. So...NEW/REbuild carb right..???...I think the Valve set up is close..But..when the rotor is pointing at # 2 The vale on #2 Cly is down/Open..so Im guessing that is wrong...

 

Correction..this was an example.. the first valve on #2 cly..is DOWN tight pushed in.. If that makes sence..If the rotor is at plug wire #2 then bouth of those valves should be open..not one of them pushed down...Right..??

 

Well when I went to #2 and the rotor is pointing at #2 wire..One of the Valves on # 2 cly is open and one is closed..so am I sapposed to then back it off to let that Valve come up to match the other...Is this where my problem May BE..???

 

Well I haven't read all this post, but, if it starts now, runs strong then starts to go bad, I wouldn't touch any valves again. Just find why your running so rich. You got a choke on that carb? Is it open when it's hot?
Dom

 

To get the timing close, you can get any hole to TDC on the it's compression stroke, (maybe 2 since you mentioned it being gooofy),make sure BOTH rockers are up and at whatever loose adjustment you are using, loosen dizzy clamp so it turns in block, rotate it in the direction needed to point at corresponding (#2 wire) location in dizzy, clamp it down. Every cylinder needs to be operating the same as that.
It might be worth mentioning again, that each cylinder only fires during the compression up stroke, when both valves are closed. It takes several strokes to get to the compression stroke, that's why we keep going back to the compression thing.
It might clear things up to mention that after #1 compression stroke, the next cylinder to close both valves and compress will be the next one in the firing order, which was posted before, but is cast on the manifold, I'm thinking.

 

Sloppy, the crankshaft rotates twice for each single rotatiin of the distributor. It is very likely that you are looking at cylinder number two on its exhaust stroke.

 

When the rotor is pointed at the number 2 wire, the number 2 cylinder should be firing so both valves should be closed. If you have one up and one down, the firing order might not be correct. The firing order should be 153624.

 

Sloppy, Each piston goes up and down more than once to get to the up stroke when the intake valve (which is above the intake manifold port for that cylinder) closes to allow compression. That TDC is when the cylinder should fire. Find compression TDC for EACH cylinder, when both rockers are up and valves are closed. Make your valve adjustment with both rockers up only! Check that dizzy is pointed at that spot where wire for that cylinder is and you should be getting close, especially if it has been running with the valve adjustment so whacked out.

 

Exactly, Dom. Sloppy, forget about the valves for now. I'm sure they're close enough to run the engine if everything else is up to snuff. In fact, I know they are...because as Dom alluded to, if it runs good for a few minutes, then everything is good 'til something changes. And that thing that's changing is the carb fouling the plugs.

 

Sloppy, To be clear, after you get compression TDC (both valves should be closed), get the valve adj. close, look at the dizzy pointer. If you need to pull wires out of the cap to match the cylinder you are working on, do it. Then go to the compression TDC of the next cylinder in the firing order (both rockers should be up for that cylinder), get valves close, check pointer, put that cylinder's wire in proper place in cap, go to the next cylinder in firing order, making sure intake valve closed so that cylinder can compress. Are you getting it?
I hear you guys, but why is one rocker open at TDC?

 

i havent read all of this but did you check the plug wires to make sure the firing order was correct. Back in high school we would swap the #3 and #4 wires on someones six cylinder and it would start and idle and but ran like crap above idle. Someone did this to me and it took me forever to figure out what was wrong with it.

 

Smart man new Fish I agree take a step back crack open a cold one take a deep breath you are learning this very quickly and all the info crashes together in your noggin and frustrate's the hell out of you don't give up you will love it when you get it right and didn't pay an exuberant amount to some one else to do it. Also here is a link to a 235 and 261 engine manual for your interest in tdc for the other cylinders.

http://www.canadianmilitarypattern.com/1960 235-261 Engine Manual.htm

 

Sounds like the ignition timing may be retarded. Loosen the bolt that holds the distributer advance to the block and slowly turn it clockwise with the engine running until you find the spot that is smoothest and highest RPM. That should be close to the proper advance setting. That may clear up the popping due to ignition retarding under load. Just a thought. Good luck.
Bob

 

http://chevy.oldcarmanualproject.com/ here is a link right on the H.A.M.B.
http://chevy.oldcarmanualproject.com/shop/1955/index.html whole thing starting at table of content's
http://chevy.oldcarmanualproject.com/shop/1955/55csm0608.html adjusting ignition points
http://chevy.oldcarmanualproject.com/shop/1955/55csm0609.html ignition timing
http://chevy.oldcarmanualproject.com/shop/1955/55csm0610.html valve adjustment

Man I hope this help's and not over whelm's I know it's allot to take in when you just want your car to run

 

I have that manual..Thanks though..

 

So Im done..Gonna put new Plugs in..Other than Fouling the Plugs..and fuel popping in the carb when I rev it..Everything else is SmOOOth as silk... Last Question...Is the Carb The only Reason the Plugs Will Foul out..and turn black within 5 min of running...?? Cause Next step is new Carb...Thanks to All For the Help..I really Believe whith a new/rebuilt Carb..Ill Be in good Shape..I couldn't have done it Without The HAMB Guys..Thanks ALL....

 

Try advancing the timing. See #373

 

don't get your shorts in a knot, man. I pointed out that I wasn't being neg. In other words, I am impress by the amount of reponses on the O.P's problem. That's All.

 

DiD it..

 

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</TD><TD id=td_post_8731144 class=alt1 style="BORDER-RIGHT: #e5e5e5 1px solid"><!-- icon and title --> Re: 57 inline 6 235..Popping,Sputtering
<HR style="COLOR: #e5e5e5; BACKGROUND-COLOR: #e5e5e5" SIZE=1><!-- / icon and title --><!-- message -->So Im done..Gonna put new Plugs in..Other than Fouling the Plugs..and fuel popping in the carb when I rev it..Everything else is SmOOOth as silk... Last Question...Is the Carb The only Reason the Plugs Will Foul out..and turn black within 5 min of running...?? Cause Next step is new Carb...Thanks to All For the Help..I really Believe whith a new/rebuilt Carb..Ill Be in good Shape..I couldn't have done it Without The HAMB Guys..Thanks ALL....
</TD></TR></TBODY></TABLE>

 

It's too late for this project but for future reference when you fix something and it goes to crap, just reverse what you did until your back where you started. I've taken plenty of good carbs and screwed them up by fixin em.

 

is your dist flooping back and forth or is the advance connected so when you advance the dist with your hand it will return back to original position??

plug fowling things???

thin engine oil or its poluted with gasoline
rings shot
engine worn out completely, rember these needed rings every 10K miles due to dirt goin past the rock catcher[air cleaner]
worn valve guides

you just may have to tear the engine down and check it out itmay be terbilly worn out as loose rings in lands and a lot of other things

 

The motor was taken apart..and rebuilt..and has all new external parts..except the carb and distributor..Plenty of pics on here of every Part..and yes the dist. does snap back if I advance by hand..

 

Assuming you are 12 volt, see if you can borrow a coil from a buddy and swap it into the mix. The whole " it runs smooth until under a load" is still bothering me. I have literally poured fuel from a 1 liter bottle gravity fed with a hose into an open intake and ran a car without the sysmtom you are having. I'm not saying your carb needs float adjusted ( black soot ) but if the ignition system is breaking down, you will also have fowled plugs. Did you ever swap in a brand new, bought today condenser?

 

best test of ign system is to put it on a older scope with the real patern and check available coil voltage
forgot that one good ignition is essential
can also check out the primary circuit and points with that

in tech school I put a fuel filter in the carb backwards, that was another problem back in 1964

sooner or later you are gonna find it sometimes takes awhile donttttt give up

 

I came back to check things. This thread is actually pretty amazing. Folks from all over the US sharing their knowledge to help a fellow HAMB member and there was almost no drama! It's not easy to figure out what's going on and give advice without actually seeing what you're talking about. Shit, I'm feeling kind of proud! Good job HAMBsters!

Sloppy, I gotta hand it to you man. You hung in there! I know this stuff can be frustrating and mind boggling when you're first learning about these old engines. I also realize it's hard to sort through everything when 10 people are giving you advice at the same time. Good job, man. Tenacity will get the job done.

I know there's still work to be done. I'm looking forward to the day when this old 235 purrs like a kitten.

 

Just a quick question for reference, you keep sayin the engine was rebuilt.
Do you know that for a fact? U keep mentioning it because u see new external gaskets, you sure they didn't just regasket stuff?
Just trying to understand it more sloppy

 

Good day Sloppy,
Hope that the new day is good to you. If you get frustrated, walk away and come back with a fresh mind later.
As far as your plugs fowling, it could be the carb, but it could also be your ignition system. If your not getting enough voltage to the ignition, (after some warm up time) then it might not be firing right. If you throw fuel (any mixture) onto the spark plugs without sufficient spark, they will foul out. many things could cause this. The battery not charging, something electronic like the coil or condenser heating up and taking a crap, etc....
I would step back and access your electrical system.
-Is it safe to assume that your car is now 12 volts?
-how about the coil? 6 volts or 12?(try another one) it might be overheating and dying.
- on another note, a 6 volt car would deliver 6 volts to its points, and coil. A twelve volt car would utilize a ballast resistor or resistor wire to kick the ignition voltage down to 9 volts I believe.12 volts is actually too much voltage for a points / coil ignition system. Cars were also wired for the starter to apply 12 volts to the coil (bypassing the resistor) at start up for easy starting. Sometimes over the years these wires can get mixed up, and you'll be applying the 12 volts, regardless of there being a resistor in the system or not. Check your coil voltage. If it's at 12 volts or higher, that's way to much. The voltage needs to be kicked down or it will fry your points. if your car was originally 6 volts there were no resistors anywhere in the wiring. This could be causing your ignition system to heat up and melt down. That would explain it running great at startup and dying down after 5 minutes once it gets hot. I've had my 235's plugs foul out almost instantly on my cars due to issues with the ignition or charging system.

Luckily your dealing with an Inline 6, one of the easiest engines to change plugs on.

-I dont think this is a problem for you but these old external advance distributors can get sloppy where they are mounted, and that can just about kill your point gap. try gently nudgeing the distributor in one direction or another while its running to see if the performance changes or even if it dies. The way that these distributors turn and advance is a very neat novel thing, but i'm seriously considering going with an HEI from Langdons in the future. A lot of people go with the pertronics, but I just work with the points. But yeah, I've really been thinking about them HEI systems, getting an incredible reliable spark and being done with it.

Point two. you asked about the timing on 2,3,4,5,+6.
The way that i adjust my valves is by starting with one.
Turn the fan by hand "IGNITION OFF!"(push on the belt if it slips) until you reach top dead center. I do this by watching the exhaust valve open and close. (located above one of the 4 exhaust manifold ports) and then watching the intake valve open and close. (located above one of the 3 intake ports)Then you just turn the motor over by hand a bit more until your near tdc on the compression stroke. If not sure you can look at where the rotor is pointing. if its right where the plug wire is at when it would fire then your there.
You could do this going down the row of cylinders, (1,2,3,4,5,6) but once you realize what your doing by watching the valves open and close you can follow the firing order and only turn the fan a bit more to get to each cylinder.
Good luck! Once you get used to doing this, you'll find it a fun part of doing maintenance and appreciate what the old timers had to go thru even more. -Al

 

Will one of you take a look at this Carb..and give me your opinion.. http://www.ebay.com/itm/1950s-60s-REBUILT-ROCHESTER-B-1BBL-CARBURETOR-7003060-1950-CHEVY-235-/321087864608?_trksid=p2045573.m2042&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3D1%26asc%3D27%26meid%3D6287742116483224122%26pid%3D100033%26prg%3D1011%26rk%3D1%26sd%3D321087864608%26

 

Look for a Carter instead. Much better carb than a Rochester.
Dom