Poly 318 wide block with a 2bbl and single point distrib troubles

Virgil J.

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Hello guys, I have a 66 with a 318 poly.

This is sort of a mess that could be hard to follow. I am a young guy who might be able to win some sort of "how low budget can you go" car contest.


I have been drving this car daily for a few years, have put many miles on it (and replaced the headgaskets 20,000 miles ago) first with the original carb - stromberg WW2 -, then with a rebuilt 2 bbl holley from an 86 dodge ram, with which the car was running really good, but eventually needed another rebuild, as I could turn in one of the mixture screws and the car wouldnt stall.
I had been driving it for a long time with from what Ive found a non-functioning vaccuum advance and no knowledge that there was an oiler on the distributor. So it was dry in there, and I wore out the shaft...eventually the distributor had a lot of play so it was a wonder how the rotor managed to stay in the middle and the motor got spark. They say theres a little more leeway with these old motors.

It seems that I kept getting crap quality distributor caps, as you get what you pay for... the metal part in the middle that touches the rotor kept gettign "chipped". Also had poor quality plug wires which I have gone through and tested and repaired.

In a cheap attemp to keep it somewhat original I replaced it with an NOS rebuilt 20 years ago Stromberg WW1 that was originally for a 61 GMC truck. The difference in these carbs is the linkage and the top half of the carb, and the fact that the ww1 is set up for a manual choke, which I hooked up. A common problem with the ww carbs is the throttle butterfly rod or whatcha callit wears out the hole its in, and the fuel leaks out, which was the case with this carb, even though it was factory reman/ rebuilt by holley co in 1989. This is usually fixed by drilling and inserting brass bushings.
I changed the points on the worn out distributor and messed up the process of doing so a few times.

Anyway I just slapped this carb on and drove it for a while, the float was sticking, and it would run until I tried driving uphill. So I adjusted this float and it helped. But the thing started running poorly. I flooded the carb a few times trying to get somewhere in a hurry an it made some loud noises when it ran, I blew up one of my mufflers. So I had friends try to help me out, some thought that it could have skipped a tooth on the timing chain.. they were saying it could have plastic teeth on it but I thought it was too old (66) for that. So I did turn the motor over by hand and tried to see if it was still at tdc on cyl 1. It seemed like the timing was ok. I could start it and it would run for about 8 seconds then stall.

Having a worn distributor shaft, I replaced the distributor with a cheap reman points one, that seemed to be of a later model origin that did not have the oiler, and had a white plastic bushing part on the middle of the shaft.
One friend said that it could have a leaky intake valve, or a blown head gasket or a leak between cylinders, so I pulled the spark plugs out, loosened up all the rocker arms and pulled the pushrods out and stuck a rubber tipped air hose in each spark plug hole, applied the air to each, and it seemed like there was no air coming out the carb or the exhaust.
The oil on the distick looked fine.
I pulled one of the head bolts on the drivers side and it looke like creamy oil like a blown head gasket but I was told this bolt goes through a water jacket where oil will get mixed up with coolant and thats ok.
I then tried my best to readjust all the intake and exhaut valves, going by the specs in the book with a feeler gauge. I did get the pushrods mixed up.
I tried running the motor again and it sounded not the best. It non-backfired (forefired?) through the carb and some flames arose that could've burnt / melted something in the carb.
I changed the carb out for a 4 barrel holley that another friend had, and did so with an upside down 4 to 2bbl adapter, with which I had to do some epoxying to fill what would be vacuum leaks. There could be a vacuum leak in the intake gasket area
Yes I know it is harder to diagnose one thing when you keep changing other variables, aka "try-thisitis".
I proved to many wiseguys that yes, the firing order and plug wires are correct.
I tried bypassing the ballast resistor. I cleaned all electrical connections and replaced the engine's ground cables with new ones. I replaced the ignition coil (any comments on using coils with built in resistors?)
I haven't replaced the condensor that is connected to the coil.
I even tried disconnecting the exhaust system incase squirrels had plugged it up with a nest or baby chipmunks and acorns .
At this point I feel like I should pull the heads off and look at the valves from the bottom, then if needed do a valve job. But my leakdown test should had told me that this is unnecessary. I am thinking of trying the valve leak test again, only this time with a screw-in tipped air gun in each spark plug hole.
I'd love to just put in another good running poly so I can go through this motor top to bottom.
????
Any ideas
 
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To me it sounds like a nasty mix of bad timing and broken carb causing a backfire that damaged your engine's internals. Maybe rod bearings? Make sure you are getting a spark. Double and triple check your timing. I'm no expert, but there are some very good troubleshooters who may help you on this forum.
 
I'm definitely getting spark and the timing seems to be ok I guess. Haven't tied a compression test. Rod bearings - maybe there is some internal damage
 
Can I suggest that we start with the basics then dive deeper as you need to?if the leak down results are good then the compression should be good.you didnt mention if you had done that lately.personally I would check the timingchain for free play.check the timing marks mechanically by removing the #1 spark plug and reference the TDC of #1 to the timing marks on the balancer.these old cars can spin the balncer especially after a number of back fire events.once it established this this is or bad, also check your distributor position to see if it is near the #1 spark plug wire.i
 
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If not then the chain has more than likey jumpedif the reference points are good and the free play is less than 4 degrees your chain n gears are usable.check for a stronv spark as well.if you are using the oem points then you really need a dwell meter to check the dwell of that distributor.googlr this for how to do that.next on the plate is if there is weak or sporatic spark then co sider restting the points lube the distributor shaft.also get some extra distributor condensers.i seen too many bad condensers n guys like you chasing after big things to find out it was a 50c item...
 
Set the timing using a vacuum guage .timing lights are only good the cars with a good harmonic balancer.
So after doing the above and it still is nor running right then it is time to check the fuel system.you dont talk about fuel filters.what about the gas tank n gaslines?have you checked the pump pressure?
I would personally find an oem carb and use that for a starting point.check flow check pressure.
 
If good check for vacuum leaks using if you have pure acetelene no OXYGEN!!!!! Just open, not fully open otherwise the acteylene flow all over and you wont know wher it is being sucked into

Unlit
of course, just raw gas from thetorch.it is heavier than propane and if there is a leak thenit will find the leak and the car will instantly pickup in rpm'sjust remember no flames should be coming from the torch at any time

:lol:
 
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Ok back to the carb if it is still running badly.take torch and stick it down thr throat of the carb while the car is running if it picks up in rpms again then it is still carb or vacuum leak related and you need to adjust the air mixture screws to try to balnce the carb out.if it doesnt then you need to investigate the carb internally.good luck!
 
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Everything mentioned so far is good, solid advice.

I'd bet on timing chain or fuel delivery.
 
Yes start with the basics, a quick way to check for a loose timing chain
move the engine clockwise with the distributor cap off until you reach T.D.C. mark the location of the rotor. Then rotate the engine counter clockwise until the rotor just starts to turn, note the reading of the timing marks. If it is more than 10 degrees your timing chain is stretched and you need to open up the front of the engine. If you have a plastic cam gear and teeth are missing you will have to remove the oil pan to clean out the gears before you clog the oil pump.
 
Can I suggest that we start with the basics tehn dive deeper as you need to?if the leak down results are good then the compression should be good.you didnt mention if you had done that lately.personally I would check the timingchain for free play.check the timing marks mechanically by removing the #1 spark plug and reference the TDC of #1 to the timing marks on the balancer.these old cars can spin the balncer especially after a number of back fire events.once it established this this is or bad, also check your distributor position to see if it is near the #1 spark plug wire.i
I am with mr. fix it here... but lets go simpler still. Epoxied carb has little to no chance... large vacuum leak would explain at least some of your issue. If you still have the 86 carb that ran, and it hasnt sat on the shelf for the past year... plan to stick it back on. with a fresh gasket (for diagnostic purposes only).
Your symptoms are a little vague to me. Did it EVER backfire through the intake before you played with it? You could have mistimed it easily... everyone does sooner or later, If it wasnt part of the original problem... its not likely the engine. Bearing issues would have involved noise before you started playing... not impossible that they got hurt... but unlikely.

1- check timing as described by mr. fix it
2 -check spark output, but weak spark usually wont start/should idle if started/die as you put load on the engine.
3- give it a carb that has a prayer.
4- change the oil... you probably have killed the old stuff by now
5- if it starts at all, somethings working. vacuum advance etc shouldnt prevent idle... vacuum leaks might. Plug off all vacuum lines... your just trying to get running again.
you can spray a little carb cleaner down the intake to help it run... if this works... you have too much air or not enough fuel
6- once she runs, try to follow mr. fix it's advice on tuning
7- if you don't have acetylene handy, propane is fine for vacuum leak diagnostic... either way be careful and keep your face back... less is more...

If any of these steps are not done in order or you get new information STOP. repost here with as complete a set of symptoms as you can.

I have learned to treat forum diagnostics as if everyone knows nothing... you can not successfully diagnose by picking the tests you want to do. I mean no offense, but if you luck into the solution... dont give yourself too much credit.

I do not mean to step on mr. fix it's advice... I agree with him... just keeping it in simple order.

Virgil J. the story of what happened is good... the symptoms we would use to "spot" problems are a little weak. Its cool, if you did this for a living you wouldn't need us. Most engines will start and run once the right pieces are in place... and never take an engine apart to find a problem... it assures you will waste the money of reassembly parts, but may not solve the issue.
 
I feel like you need to put your best 2 bbl back on.
 
Fuel delivery seems fine, I put a new fuel pump on it 3+ years ago when I got the car, and put a new fuel filter on it a month ago. After running the motor, there's plenty of fuel squirting out after loosening up a fuel line hose clamp.

I am going to change the oil which has been polluted with gasoline (cant flip - yeah you're right), and maybe try putting the 86 holley carb back on...
mr fix it - I suppose I would like to check if the harmonic balancer has gone out of whack - also I will try the propane...
traintech - I do want to check if the timing chain has skipped. Did they have plastic teeth in 66? ( I see denture jokes coming!)



On a side note- about this 50 year old car with one heck of a story -
Funny how "mechanics" (parts installers?) can make a living nowadays without ever touching a points distributor or a carburetor! Yes, I am part of that generation, but I'm learning. The only time I've ever dropped the car off to be solely worked on by someone else was to a reputable alignment shop, I was very nervous about (no impact guns on my lefty lugnuts please!) and asked if they had experience with older vehicles, they'd said yes, we just aligned a 53 Dodge (front coils I think)...anyway the car rode a little straighter, the guy said "did all we could but could only adjust it so far"- pucks- -- turns out they hadn't taken the torsion bars into consideration! (I thought of this a year later) So I really only trust the older guys for advice. What really bugs me is every car guy I know's brain is in volkswagen or subaru world... Nothing here offends me it is all great to read.

Thank you for your responses and work deciphering this
I usually would never take an engine apart to find a problem - this being my only car I did so outdoors in a snowstorm, in a panic with drunk old guys giving me screwed up advice...
Still, the car has been one of the most useful things I've ever owned
 
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Fuel delivery seems fine, I put a new fuel pump on it 3+ years ago when I got the car, and put a new fuel filter on it a month ago. After running the motor, there's plenty of fuel squirting out after loosening up a fuel line hose clamp.

I am going to change the oil which has been polluted with gasoline (cant flip - yeah you're right), and maybe try putting the 86 holley carb back on...
mr fix it - I suppose I would like to check if the harmonic balancer has gone out of whack - also I will try the propane...
traintech - I do want to check if the timing chain has skipped. Did they have plastic teeth in 66? ( I see denture jokes coming!)



On a side note- about this 50 year old car with one heck of a story -
Funny how "mechanics" (parts installers?) can make a living nowadays without ever touching a points distributor or a carburetor! Yes, I am part of that generation, but I'm learning. The only time I've ever dropped the car off to be solely worked on by someone else was to a reputable alignment shop, I was very nervous about (no impact guns on my lefty lugnuts please!) and asked if they had experience with older vehicles, they'd said yes, we just aligned a 53 Dodge (front coils I think)...anyway the car rode a little straighter, the guy said "did all we could but could only adjust it so far"- pucks- -- turns out they hadn't taken the torsion bars into consideration! (I thought of this a year later) So I really only trust the older guys for advice. What really bugs me is every car guy I know's brain is in volkswagen or subaru world... Nothing here offends me it is all great to read.

Thank you for your responses and work deciphering this
I usually would never take an engine apart to find a problem - this being my only car I did so outdoors in a snowstorm, in a panic with drunk old guys giving me screwed up advice...
Still, the car has been one of the most useful things I've ever owned
Virgil, yes they did have plastic teeth on the cam gear in 1966. I do believe it was the middle 80's when they stopped. Also while your checking make sure your point gap is correct. .0017 on the high point of the dist. cam. Since you have done so much trying to fix this you will have to start in one area first and make sure everything is correct, (Ignition, then fuel, exc.) And please if you get different symptoms after each step write us back. We have to stick together to keep these great cars on the road.
 
mr fix it - I suppose I would like to check if the harmonic balancer has gone out of whack -
traintech - I do want to check if the timing chain has skipped. Did they have plastic teeth in 66? ( I see denture jokes coming!)
Same test here...

... Nothing here offends me it is all great to read.
Thats good... we can seem overbearing at times (by we I mean me)...

Still, the car has been one of the most useful things I've ever owned
They all beat the hell out of walking... but glad you didnt subcome to the vw/subaru peer pressure.
 
I'm glad it is solid simple advice that I have to offer. :)
I would be careful with the propane as it tends to float around so keep it concentrated when using it.
Please have the air cleaner on the car with a good base gasket so it doesn't get sucked down the throat of the carbs and give you impression you have a vac leak where you may not have the leak where you think you have the leak

The reason I suggested acetylene is that it is chemically heavier than propane..

If you do put it down the carb and the engine picks up then it could be a carb issue because the fuel to air ratio will appear to change.


Please, please, please, let us know what you discover.
There are many others on the forum that will learn from your experience here

Once the solution is found, consider changing the points system to an electronic setup from a 1970's system.
It's easy to convert and very trouble free for future.
 

...I do not mean to step on mr. fix it's advice... I agree with him... just keeping it in simple order.

Virgil J. the story of what happened is good... the symptoms we would use to "spot" problems are a little weak. Its cool, if you did this for a living you wouldn't need us. Most engines will start and run once the right pieces are in place... and never take an engine apart to find a problem... it assures you will waste the money of reassembly parts, but may not solve the issue.

No offense taken CantFlip, if we can help this member out then it's all worth it.

There are so many things that can cause what happening here and using the KISS method is the best approach but if one thing is over looked a lot of time and money can be wasted
 
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