3 Symptoms

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Valhallo

Well-known member
Joined
Aug 3, 2011
Messages
367
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2
Location
Utah
My Car
73' Grande
I've got three things that have popped up that I'm trying to figure out with no luck so far.

1- I can smell pretty heavy fuel inside my car. It doesn't smell like exhaust, but straight gasoline. It seems to be even more prevelant when I get on the gas.

2- My manifold vacuum doesn't read steady. Well, it reads pretty steady when I adjust my timing way down to near TDC, but anything higher and the needle on the gauge is all over the place.

3- If I have the car in park drive or neutral and I let on and off the gas 3-4 times the engine dies on me. (unless i'm in drive of course, then it nearly stalls out, but winds back up) Would that be the engine flooding?

Anyways, I'm wondering if this is a carburetor problem. I rebuilt my carb 2ish years ago and had a shop tune it up for me. :blush: I thought it might be a sticky valve, so I put a whole ton of seafoam in my engine oil, ran it for a couple dozen miles and then did an oil change, adding a tad bit of seafoam to the new oil, but with no success. All three symptoms are still present.

Any other ideas on what the problem might be or even that it's the same problem but my solution sucked?

Any help is appreciated,

-Zac Hirschi

 
Sounds to me like a carb issue. All three problems could all be related to a bad carb. What kind is it? Do you have a known working one you could swap for test purposes?

 
Hey Zac,

This just popped up?

Sounds kind of like a carb issue to me.

If you don't have a leak and it reeks of fresh gas, then I'd be thinking flooding as well.

Have you checked for a vacuum leak?

What kind of carb do you have?

I have an Edelbrock 1405 that you could borrow to see if your problems go away.

It might be a bastard to get it on depending on what's on there now.

Let me know if you want to try my carb.

I could probably meet you at Cabellas sometime this week.

Scott

 
What kinda build is she? And what size of carb? A carb that is too small for your car..Will flood out..And will give you all sorts of issues....One of the best checks you can do...Is pull a few spark plugs...See how they are burning....If its all black and coverd in oil from the lack of being burnt..You know she is getting too much fuel...If she is a nice coco or tan color..Then you know she is burning the right amount of fuel....If the plugs are allmost white and dry..You know she is runing way too lean..and your carb is too big.....Just remmeber too rich means your carb is too small usualy...Its not able to deliver enough air into your cars motor to burn the fuel.....Too lean carb is to big and sucking more air than gas....the Fix all counts on the carb and your build....Your cam specs...2 or 4v...Manifold..Single or dual plain..and such.

And thats if its a carb issue...But checking the spark plugs is a good way of checking if she is burning right.

 
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What kind of carb is on it? If a Holley, check the float levels, and pull the fuel filter and screens and make sure no trash is present.

What kind of engine in your car 302? 351C?

timing is sounding way off. Could your balancer have slipped (outer ring slipping on the rubber leads to actual timing and marks being very different.) Mechanically checking cylinder 1 for TDC will tell you if this occurred

Poor ignition will cause fuel smells too, don't rule it out until you have checked timing and the condition of the ignition.

 
Best sight I've seen so far. Check the different scenarios

http://www.secondchancegarage.com/public/186.cfm
That is a great site with good info. Bookmarked.

What kinda build is she? And what size of carb? A carb that is too small for your car..Will flood out..And will give you all sorts of issues....One of the best checks you can do...Is pull a few spark plugs...See how they are burning....If its all black and coverd in oil from the lack of being burnt..You know she is getting too much fuel...If she is a nice coco or tan color..Then you know she is burning the right amount of fuel....If the plugs are allmost white and dry..You know she is runing way too lean..and your carb is too big.....Just remmeber too rich means your carb is too small usualy...Its not able to deliver enough air into your cars motor to burn the fuel.....Too lean carb is to big and sucking more air than gas....the Fix all counts on the carb and your build....Your cam specs...2 or 4v...Manifold..Single or dual plain..and such.

And thats if its a carb issue...But checking the spark plugs is a good way of checking if she is burning right.
I pulled my plugs and they are a brown/red, but I also used to use fuel additives every fill and someone told me that the additives can give the red coloring. The plugs are actually pretty dry. The motor is a stock 351C with the original motorcraft carburetor.

IMG_3853.JPG

IMG_3859.JPG

Hey Zac,

This just popped up?

Sounds kind of like a carb issue to me.

If you don't have a leak and it reeks of fresh gas, then I'd be thinking flooding as well.

Have you checked for a vacuum leak?

What kind of carb do you have?

I have an Edelbrock 1405 that you could borrow to see if your problems go away.

It might be a bastard to get it on depending on what's on there now.

Let me know if you want to try my carb.

I could probably meet you at Cabellas sometime this week.

Scott
Well my sinus' are just starting to clear up, so the problem is probably not just now popping up, but its the first I've known about it. I definitely appreciate the offer on letting me borrow your carb though, and I might take you up on that if that's what it comes down to, but I don't wanna put you out of your way coming to Cabellas. If borrowing your carb will be helpful to me, I can definitely meet up with you somewhere on your side of the point of the mountain. I'll PM you about it soon.

 
1. 2 or 4 barrel?

2. What IS your manifold vacuum?

3. What is your vacuum at the distributor?

4. Is your vacuum advance working?

5. Have you checked this?

pht20020301cr_s07.jpg


6. Have you checked your fuel filter & rubber hose at the carb?

 
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Forgot to mention...

Make sure your PCV system is good. Also check for vacuum leaks.
I took the vacuum reading directly from the intake manifold, so the only leak there could be are the gaskets, correct?

What kind of carb is on it? If a Holley, check the float levels, and pull the fuel filter and screens and make sure no trash is present.

What kind of engine in your car 302? 351C?

timing is sounding way off. Could your balancer have slipped (outer ring slipping on the rubber leads to actual timing and marks being very different.) Mechanically checking cylinder 1 for TDC will tell you if this occurred

Poor ignition will cause fuel smells too, don't rule it out until you have checked timing and the condition of the ignition.
I looked into confirming TDC with a previous problem recently, and cylinder 1 is showing correct timing, but my timing has been doing funny things recently anyways. Right now my timing is set to 16 BTDC running 91/92 Octane fuel. At this timing my vacuum needle drifts back and forth between 14.5 and 15.5 Hg.

By the way, sorry for the crap pictures.



1. 2 or 4 barrel?

2. What IS your manifold vacuum?

3. What is your vacuum at the distributor?

4. Is your vacuum advance working?

5. Have you checked this?

P1010475.jpg


6. Have you checked your fuel filter & rubber hose at the carb?
1. 2 or 4 barrel?

2 barrel

2. What IS your manifold vacuum?

95% sure its the stock original intake. stamped 13728548

3. What is your vacuum at the distributor?

drifting between 14.5 and 15.5 @ 16 BTDC

4. Is your vacuum advance working?

No, it is plugged, otherwise it puts me over safe total advance

5. Have you checked this?

I have not checked that. In fact, umm... that's the accelerator pump diaphragm, yeah? Lol, been a while since I took apart carb. What should I be looking for with it?

6. Have you checked your fuel filter & rubber hose at the carb?

Yes. My fuel filter is fine and my rubber hose is sealed on without any cracking.

 
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If your timing is doing funny things, pull the distributor! Clevelands are known to shear the pin that attaches the drive gear. That was why I asked what type of engine :(
When I pull it, is there any sort of marking I need to do to reinstall it correctly to make sure the gears match up?

 
If your timing is doing funny things, pull the distributor! Clevelands are known to shear the pin that attaches the drive gear. That was why I asked what type of engine :(
When I pull it, is there any sort of marking I need to do to reinstall it correctly to make sure the gears match up?
Yes, definitely! If you don't have a Chilton repair manual, you might want to pick one up. Although 90 pages are dedicated to "Emission Controls", compared to 102 pages on "Engine and Engine Overhaul". What does that tell you?

Anyway, put a mark on the distributor body to show the position of the rotor, then put a mark on the distributor body and a mark on the engine to show the position of the dizzy in relation to the block. Don't try to start or turn over the engine until you reinstall the dizzy, or you'll have much more work to do. When you try to drop it back down, you might have to start it quite a bit to the clockwise or counterclockwise position to get the gears to mesh, but when seated, the marks you placed should match up fairly well. If not, put it out and start over. If the engine has been rotated for any reason, you'll need to do things a different way.

Let us know how things go.

 
Awesome. That'll be this Saturday, so we'll see what happens then. If it's still no luck, then I might be talking to Utard.


So how exactly would a sheared pin effect my engine? What would be the effects? I suppose more of what I'm asking is if infact the pin is sheared, what changes should I expect in fixing the problem?

 
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Before you pull it bring the rotor to the #1 plug on the cap. Then look at your timing mark on the harmonic balancer and hand move the engine until the line is on the zero. You can't go wrong from there.

 
b] I have not checked that. In fact, umm... that's the accelerator pump diaphragm, yeah? Lol, been a while since I took apart carb. What should I be looking for with it?[/b]

The easiest way to check the accelerator pump is to put it back on the base and the press the lever in until it bottoms out. While it is in, put your finger over the acc pump port outlet on the inside of the metering block. Then let go of the lever(arm). It should not move if the acc pump diaphragm is not leaking and holding air.

Or you could just drop $10 bucks and replace it? Or better yet, get a rebuild kit for $35, plus a couple cans of carb clean and just rebuild the whole thing while it's off. If it hasn't been rebuilt in 3-5 years, it could probably stand a freshen up.

That would be my suggestion and then you would be done with guessing if the carb is working right.

Just clean everything like you intend to eat off of it before you put it back together and blow it out real good.

 
I pulled the distributor. There were a couple of specs of metal shards on below the drive gear. Is that anything to be alarmed about?

Back on topic, I knocked the drive gear pin out and took a look at it, and it seems fine. It goes all the way through the gear and both ends of the rod.

DSC_3648.JPG

DSC_3652.JPG

DSC_3653.JPG

Back to the drawing board, I guess the next step is to look at my carb. I'm off to O'Reillys right now.

 
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