Whats the plate under the carb? Are you running points or electronic dist? What size jets are in the carb? what power valves are in Primary and seconary?
have you checked the springs/weights/ distributor advance shaft for freedom of movement?
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Whats the plate under the carb? Are you running points or electronic dist? What size jets are in the carb? what power valves are in Primary and seconary?
have you checked the springs/weights/ distributor advance shaft for freedom of movement?
Unfortunately I don't have the means to have it towed nor have I found anyone close to me that works on these types of engines/vehicles. I am trying the best I can to figure this out it doesn't make sense, that I can be on TDC (I have bore scoped the number 1 cylinder and have confirmed TDC on compression stroke) set the dizzy rotor at number one and set the cap on ensuring the number one spark plug wire is set to that point. I even took my carb back off and reset everything and still no start. I wants to start and no matter what adjustment I do to the dizzy nothing changes much.
With cap off visually confirm rotation of rotor, then confirm the wires are on cap in correct rotation and sequence
Curious how you could scope the #1 cylinder at TDC. Piston is at the top of cylinder and both valves closed, zero space for a camera. And unless you've also got the valve cover off to witness both valves are closed fully, you could be 180 deg out.
QOUTE;
Hey guys, I need some help or guidance, I have a newly pro built 496 for my 1969 camaro, it was originally dyno’d by the company it was built by so it has been run.
1.) Pro built and ran on the dyno
it got shipped to us and We installed it into my camaro, its mated to a 700r4. When I first got it running it would run but not very well. It had about 6 inch of vacuum at idle.
2.) Vacuum is too low
And didn’t like off idle much and would be around 700rpms and the exhaust would burn your eyes.
3.) Running way too rich and probably not enough timing
It has a quick fuel 830 carb with electric choke on it and a msd hei ignition with mech advance. I first tried to tweak the carb setting the floats and then the mixture screws but no change.
4.) Low vacuum and rich idle usually points to high fuel pressure, high float setting and or power valve staying open
I changed out the fuel with fresh 93 and started messing with the distributor.
5.) Octane will not correct for carburetor adjustments/settings
I found that the cap was damaged so I replaced the cap and rotor, set the engine on tdc, at 0 on the crank verified it was on the compression stroke but I can’t get the distributor to point exactly to #1 cylinder, I can get close but not exact when at zero on the crank.
6.) If you are truly on compression stroke this should be close enough to start and adjust from there
i have verified plug wires are in correct location with running order but now after all that it starts and now dies right away. I’ve pulled all plugs they were wet with fuel mostly likely, I cleaned them took the carb off and reset everything I could see but still nothing.
7.) There is no such thing as cleaned fouled / wet /fuel soaked spark plugs, they will not fire reliably. Replace them
I have tried to adjust the timing by turning the distributor both ways and still no change. I am running a mechanical fuel pump.
8.) See #3 & 4
I am waiting for my fitting to come in so I can install a gauge and see my pressure. My carb has sight glasses so I can see the float levels and they are set to just below half way.
9.) See #3 & 4
Right now I have the card choke set to be closed when starting. I have tried to adjust the idle throttle screw from full closed to slightly open with no change. My issue is I am not sure if it’s a timing issue or fuel issue.
10.) See #3 & 4
I talked to the engine builder and they told me that I should have around 14 inches of vacuum at idle.
11.) See #2, 3 & 4
Not sure if it’s running to rich and flooding the cylinders, when I bore scope number one I have a little fluid built up in the corner of the cylinder wall on top of the piston but I don’t know if that’s oil or fuel. I am assuming it’s fuel because the plug is wet and smells like fuel not oil.
12.) It’s RUNNING TOO RICH, See #3 & 4
I set the idle mix screws to 1-1/4 turn out from stop which is even leaner then what it comes from the factory. I was told that the engine parred with this trans should run rich but I have a feeling it’s too rich but I don’t know how to find that out or what to look for.
13.) See #1, 2, 3, 4, 5, 6 & 7
I have it running but like I stated I have to have the idle really high, over 1200rpms to keep it running. Fuel pressure is about 7psi at the carb. I have shut the idle screws and the vehicle does die after a min, it will run with the screws about 1/2 turn out but beyond that it struggles and smells really rich.
14.) See #3 & 4, lower fuel pressure 7 is too high
I reset the choke and fast idle and still no change.
15.) Of course not, it’s not the problem
When I read vacuum from the carb full manifold vacuum port it’s around 13-15 psi at 1400rpms.
16.) Vacuum will be higher at 1400rpm, BUT it is not 13-15 at idle, see #2
But when I close the throttle to bring the idle back down the vacuum drops and the vehicle will eventually die.
17.) See #2
I sprayed down the whole intake and carb with carb spray and no leaks were detected. Not sure how it’s running so rich with only 1/2 turn out on the mixture screws u less I have a power valve issue.
18.) See #3 & 4, also check throttle blade transition slot exposure
I even checked the breathers on the valve covers to see if they were pulling vacuum under load and they were not so I don’t think the intake manifold is leaking either.
19.) Usually a vacuum leak runs lean, not rich. But you could plug both (all) breathers (tape or otherwise) connect vacuum gauge to dipstick tube to be sure
Hey guys so I took my carb out and checked the power valve it’s a 6.5 and it’s not blown i tested it with my vacuum gauge.
20.) 6.5 power valve will open at 6 hg, see #2
I also removed my intake manifold and changed the gaskets and resealed it. Put new plugs in and changed the oil and filter and started it up and same results.
21.) Of course it doesn’t run any different, you have not solved the WAY OVERLY RICH and/or timing issues
I think I’m still possibly off timing, I removed my valve cover and set number one cylinder on compression stroke and tdc with my balancer set at around 13 and the distributor rotor was pointing past number one closer toward the center of the engine, but I set the cap on and put number one plug wire on where the rotor was. Like I said before it starts but I can’t get it to idle to set my initial timing. According to the engine builder initial timing is 13 total 36.
22.) Are you setting/turning the distributor the same direction as distributor’s rotor rotation, if so you are RETARDING ignition not advancing (chevy’s rotor usually turn clockwise), advance distributor counter clockwise
I’m trying to reset my carb after messing with all the adjustments. I am running only mechanical advance.
23.) See #3 & 4, also check throttle blade transition slot exposure
The engine builder told me not to run vacuum advance on the motor so I have that blocked off on both the carb and the distributor.
24.) Vacuum advance will not effect starting the motor, vacuum advance has nothing to do with high performance, vacuum advance is a fuel economizer
I pulled the distributor and rechecked all the timing, set rotor exactly on number one and 0 tdc and now it won’t start. So I have to figure out what happened now. It cranks strong but now no start.
25.) Check spark see #7
Unfortunately I don't have the means to have it towed nor have I found anyone close to me that works on these types of engines/vehicles.
26.) You've spent a considerable amount of money on a pro-built motor to NOT have the means to fix it. And, I can not believe you can not find someone in MIAMI to help you.
I believe you are either WAY over your head or playing a sick joke on us, if this is a joke end it now.
If you are serious, YOU CAN’T AFFORD to continue like this without risking sever motor damage, GET SOMEONE LOCAL TO HELP YOU OR TOW IT TO A SHOP THAT CAN FIX IT!
I am trying the best I can to figure this out it doesn't make sense, that I can be on TDC (I have bore scoped the number 1 cylinder and have confirmed TDC on compression stroke) set the dizzy rotor at number one and set the cap on ensuring the number one spark plug wire is set to that point. I even took my carb back off and reset everything and still no start. I wants to start and no matter what adjustment I do to the dizzy nothing changes much.
27.) See #26
Please, I’m not trying to be disrespectful, cruel or anything else, however your thread leads me to believe you don’t have the knowledge or experience to fix it yourself without an experienced person there on site to help you.
PLEASE minimize your expenses and get someone or a shop to help you before it’s too late……
36Sedan, that was quite a pile of work to put together. Good job on that! Everyone here knows you to be a straight shooter and not someone who would go off on a tangent of some sort... ( unlike .... ME!)
The only thing that I wanted to add to the OP, if and when you get it running again. Install your vacuum gauge while tuning for your idle, NEVER let vacuum go below the setting of your power valve plus a half inch. So if your PV is a 6.5 then don't go below 7 inches of vacuum. The cam may need 12 or 1300 rpm's to maintain that much vacuum. But that's the price of horsepower sometimes. We didn't select the components or know what they installed so can't help you beyond what we've already discussed.
That's why earlier I suggested you remove the power valve and plug it - if things got better, then you can search for a lower numbered valve. Or like me, just leave it out. I don't spin my motor fast enough , long enough, to get lean enough to hurt it. It's a street car. And I freely admit, I don't know you, your engine builder or your personal situation... but the guy who built this needs to be contacted and see if he can help you sort this out. If he's turned his back on you... perhaps others need to be warned of the situation?
Turn out the lights, the party's over.
A great summary, 36 Sedan! You're a gentleman.
i dont understand . it was run on a dyno but now wont run ? look to what you changed after getting it home .
I appreciate all the replies and help, this isn't a sick joke I promise you, I have had this car for 20 years and finally have had a chance in my life to restore and build it up the way I want. I did not build my power train I bought a fully dressed long block that had been dyno'd. At that time I did not have the vehicle it was at the shop that was doing some of the work for me and they installed it so I am not sure what happened between all that to when I got it. I am trying to learn as I go I am use to newer vehicles where I can monitor O2 sensors and fuel trims. I am unable to do this on this vehicle and yes maybe I am in over my head but I still trying to learn so I can be able to work on the vehicle myself when I need to.
I live in South Florida, just every one calls it Miami but I am not in Miami, the closest shop with dyno that has a good reputation for me is over 30 miles away and to tow it there and have them work on it and tow it back, I unfortunately don't have those funds at the moment so I am trying to learn and work on the things I can at the moment. I understand I can damage something, and that's why I am here asking for help so I can learn and possibly not have to spend the money to have someone possibly take 30 mins to correct a simple issue (if that's the case).
Once again I thank you for all your feed back, I understand its very hard to attempt to diagnose someone else's issues without seeing or knowing all the information, just don't knock me for not knowing something that maybe you deal with on a regular basis or have a lot of experience with and seems easy to you. I am learning new things every time I work on the car. I haven't had a chance to work on it lately so that is why I have not posted in a little while. I have not given up on it and will go over everything you all have listed and get back to you all. Thank you.
OK, assuming all is good with the motor. This may simply be a big cammed motor and carburetor not set up for it. So lets try something very simple first and get the motor idling so we can go from there.
This is an article I wrote for my car club that may get you going in the right direction;
Perhaps this will help? https://www.youtube.com/watch?v=hhrlN59BA_s
I don't agree with his "final solution" with bumping the motor over to get the dizzy to drop in. But that isn't where we are right now. At least review it and maybe it'll help.
Denny you can't make it any simpler than that. Been doing it that way for over 50 years
Yup - works good. Note to self, do not get between the screwdriver and any point of ground on the car - ask me how I know this... Yikes - it'll give you a good wake up jolt. Not to get too far off, but years ago, I thought I'd help a friend time his Triumph motorcycle - I mean how hard could it be to hook up my chrome plated Sears timing light to the #1 and give it a go. Well those old bikes were positive ground and when I squeezed the trigger I felt the furry of the coil down to my toes.Quote:
Originally Posted by DennyW
LOL!!! Been there done that!Quote:
Originally Posted by glennsexton
Ok so I did go and get a spark tester and with it installed and just turning the distributor I had it light up. I got in contact with the engine company to find out my plug gaps and timing again. They told me the plug gaps should be .35, the new ones I got were not that gap they were much smaller. So I gapped them all to .35. They also told me the timing should be 12 initial and 36 total.
So with all the plugs out I put a little bit of oil down all the cylinders in case of wash down, I then pulled bank 1's valve cover off and watched the intake valve one cylinder one open and close and then set the crank pully on 0 degree's. Looked at my rotor and it was pretty much pointing to number one cylinder. I marked the housing for the rotor location and put the cap on and put number one at the mark on the dist. I cranked the motor over a few times to let the oil in the cylinders move around, put all the plugs back in, and exchanged the oil.
I pulled the carb off and went through it I set both primary and secondary throttle plates so you can just barely start to see the idle circuit groove. I exchanged the power valve from a 6.5 to a 3.5 even though everything I read told me that that will not effect idle. I set the idle mixture screws to only 1/2 turn out from stop to start. I re-installed everything and I am going to flush the fuel system and ensure I have fresh fuel in it and attempt to start it this weekend. If you guys can think of anything I might have missed please let me know.
This is true normally, because the power enrichment circuit operates via venturi vacuum (fuel is introduced above throttle blades through the boosters). However there are a couple of exceptions;Quote:
Originally Posted by Camaro350
1). If the power valves diaphragm is damaged, it can leak and pull fuel in through the vacuum passages.Skipping past this, if the throttle relationship and low vacuum are a contributing problem changing to a lower value PV will not help it (may make it worse). While tuning the PV circuit is essential and contributes greatly to performance, I would not lower the value until I had it running correctly.
2). The idle stop on the carb is set too high combined with low vacuum, the low vacuum opens the the valve with the throttle blades opened enough to introduce the fuel through the boosters. Usually this condition also activates the transition circuit adding even more fuel.
Unfortunately, guessing at this is not the answer.
I'm going to ask a few questions that may have been asked already but I did not see when scanning back through your thread (apologies if it has been asked), so at the risk of redundancy;1). Is this a NEW or used carburetor?At idle you should NOT see any fuel coming through the boosters. If you are unsure what the boosters are, just ask we'll explain, no need to be embarrassed.
2). While it is running at its lowest idle speed, have you looked down into the boosters to affirm NO fuel is coming out of them.
At IDLE, you should NOT see any fuel entering the motor, as the idle circuit's entrance is below the throttle blades (transition circuit as well for that matter). So, if you see fuel entering the motor at idle, you have another problem.
If this is a used or rebuilt (even from the manufacturer) there could be an error in assembly causing fuel to enter the motor from a source it should not be coming from. Often, it is a simple as a misaligned or incorrect metering block or gasket.
If this is a new carb, and you see fuel entering through the boosters at idle. Contact the manufacturer for directions on what they want to do to correct it for you.
Good luck!
First and foremost get and use a vacuum gauge when doing any tuning! You may be wasting time and effort guessing at what's happening. I think you said you had a timing light. Is that correct?
Ok I know this is way basic, but consult a Haynes , Ciltons, or similar manual and confirm that you are looking at #1 cylinder, as different manufacturers put them on different sides.
Oh, and that would be .035 on the gap.
.35 would be about 3/8"
Yes everything is new on this engine, it is a complete build. I just got a new distributor because I noticed that the cap was damaged due to shipping possibly so I replaced the whole thing with a DUI HEI.
Yes I’m sorry I did mean .035 on the plug gap.
So I put fresh gas primed the bowls to halfway in the sight glass and tried starting it. It wants to start but won’t. When I open the throttle plates it starts but then quickly dies and coughs through the carb. I rechecked the timing, the pictures shows you the location of everything after I bump the motor until after number on cylinder intake valve closes. I set number on plug wire on the location of the rotor and go around from there in firing order. Attachment 72296Attachment 72297Attachment 72298
JMHO, but appears you have two problems;
1). There may not be enough initial timing on the motor.
2). Appears the carburetor is suppling too much fuel to the idle circuits.
I would give it a little more timing (turn distributor counterclockwise), and try starting it with just a 1/4 throttle. The carb may be too rich to start with a closed throttle, opening the throttle a 1/4 may be enough to get it off the idle circuit but not enough to be too lean when it's cold.
If that starts it, I would check the idle air bleeds in the metering blocks, occasionally a carb gets set wrong from the factory or may have something in the air bleeds (packing material). It could also have been modified by someone and sent back, then sent to you as new. Check it to be sure, if everything is clear and looks good and the air bleeds are the correct numbers, I would then contact the carburetor's manufacturer for further advice.
Ok I will try that tonight starting it with more advanced timing and open throttle, in the mean time here are the specs for my carb.
Barrels 4
Booster Down Leg
Brand Quick Fuel
CFM 830
Choke Electric
Circuit 2
Emission Code 3
Fuel Gasoline
Fuel System Carbureted
High Speed Air Bleed 28
Idle Air Bleed Size 70
Marine Use No
Material Aluminum
Model Super Street Series
Primary Main Jet 78
Primary Power Valve 65
Primary Pump Nozzle Size 33;35
Product Type Carburetor
Secondaries Mechanical
Secondary Main Jet 86
Supercharged Application No
Throttle Bore 1-3/4 inch
Part Number SS-830
So when you were bumping the engine over until the intake valve closed--------then just what exactly did you do???????
Quote:
Originally Posted by jerry clayton
So I got home cycled the motor over until I was at 15 degrees before TDC and on compression stroke for number one and lined up my distributor housing on the rotor for number one plug wire and after that I assembled and wired the dizzy and it was close to cranking, after I messed with the idle mixture screws put them one and a half turns out and opened up my throttle plates on my primary it started right up. I didn't have much time to mess with it after that so I will be putting a timing light on it but it seemed like it wanted a lot of advanced timing to run. I will update hopefully once I get a timing light on it and see if I can get it running right. ThanksQuote:
Originally Posted by 36 sedan
