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  #31 (permalink)  
Old 02-15-2012, 03:51 PM
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the epoxy job looks good, but let me tell you I have seen 'em fail after some time, right now my own C30 is having this problem, they leak a lot, and after 2 days I have to prime the carb to start it up, gives me no driveability problems though, just the inconvenience of removing the air cleaner to fill up the fuel bowl before cranking.

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  #32 (permalink)  
Old 02-15-2012, 05:23 PM
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Quote:
Originally Posted by Augusto
the epoxy job looks good, but let me tell you I have seen 'em fail after some time, right now my own C30 is having this problem, they leak a lot, and after 2 days I have to prime the carb to start it up, gives me no driveability problems though, just the inconvenience of removing the air cleaner to fill up the fuel bowl before cranking.
I'll go ahead an inspect it if that turns out to be the problem or, knowing my luck, one of the problems. I may just have to try using plugs.
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  #33 (permalink)  
Old 02-19-2012, 03:56 PM
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As planned in post #25, I went ahead and cleaned out the fuel filter today. There was quite a bit of crap, very similar to the stuff found when the truck began having problems from contaminated fuel over a year ago. See post #19 on page 2 and #38 on page 3 for reference images.

I washed everything out with water, dried it all up using shop towel and reassembled the filter.








-----




Next item on the list was to check the fuel pressure. I went to Harbor Freight and swapped out my fuel pump test kit for a new one since mine was missing the t-connector.

I installed the t-connector in place of the fuel filter and hooked up the gauge to it.








I then performed the fuel pressure test three times. You can see the video of all three tests below.


The first time, fuel starting shooting out where the t-connector was because I had not clamped it down tightly enough. The gauge was showing 7 psi. I did rev the engine and it was hesitating. I loosened up the fuel hose to relieve pressure and reset the gauge to "0".


The second time there were no issues. I let the truck run for several minutes and revved it a few times and there was no hesitation. The gauge showed 7 psi. I again loosened up the fuel hose to relieve pressure and reset the gauge to "0".


I then did it a third time. Again, it showed 7 psi.


I did not get to do a volume test today because I did not have someone available to help me out so one could keep an eye on the fuel and the engine.




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  #34 (permalink)  
Old 02-19-2012, 04:45 PM
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A note on the video in the previous post:

- At the very beginning, the gauge is already at around 5 psi, most likely due to the priming of the accelerator pump. It was at zero when recording was begun but the parts during which the truck was not running were cut out to save time.

- The fuel pressure is seen dropping slightly as the engine is heard revving at the 3:38, 3:52 and 4:12 marks.



If I remember correctly, the fuel pressure should be 5 psi. Is that right? If so, how should I lower it from 7 psi?
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Old 02-19-2012, 06:21 PM
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From what I read, it would like you have a timing problem.

Get the truck warmed up and running and set the timing BY EAR.

Rev the engine up some, maybe 3000 rpm and move the dist more and less advance. The engine should speed up and slow down some.

Set it to where the engine is running the fastest, then back just a little bit.

tighten everything up and drive the truck and see if it helps. If it does, you have a problem with your timing!
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Old 02-20-2012, 07:26 PM
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Hey BigRoy,
Quote:
Originally Posted by BigRoy1978
From what I read, it would like you have a timing problem.

Get the truck warmed up and running and set the timing BY EAR.

Rev the engine up some, maybe 3000 rpm and move the dist more and less advance. The engine should speed up and slow down some.

Set it to where the engine is running the fastest, then back just a little bit.

tighten everything up and drive the truck and see if it helps. If it does, you have a problem with your timing!
Several suggestions have been made as to what the real issue(s) are, and I am trying to go through them one by one. Timing may very well be an issue since it was set by ear a few months back, and not by using a timing light. When it was set by ear, it was running perfectly. Just a couple of weeks ago it decided to start having these weird hesitation problems.


Got to do some work on the truck today. Continuing with the list in post #25, I installed a new thermostat. The bolts for the thermostat housing looked like crap. And I just cleaned 'em back in June of last year. (see post #130 here. Anywhoo, in went the Fail-Safe 195 degree thermostat. The bolts got cleaned up using carb cleaner and a wire brush. The flush was not finish today.







I then fired up the truck and found that the recently cleaned glass filter was leaking fuel. Once everything got fitted ans tightened down, I gave it another start and allowed the truck to warm up for a few minutes before going for a spin. The truck was still not wanting to run smoothly so I just let it run in Drive on its own at about 20 mph up and down a small street. I kept an eye on the temperature the entire time.

Now, this truck has two temperature gauges: one on the dash and the other below the dash, about right in the middle so both driver and passenger can see it. In the past, I have noticed that the temperature on the goes up a lot more slowly than the reading on the gauge below the dash. But they have always come to the same temperature. Not today. Today, the temperature reading on the gauge below the dash was much higher than the gauge on the dash. I have not taken the time to trace which gauge connects where, but I am guessing one is giving the coolant temperature and the other is giving the engine temperature. Sound about right?






After the first spin in the truck, I pulled over and revved the engine again, all the way up to 4,000 rpm at times. I noticed that the truck routinely hesitated for a split second at the 2,500 rpm mark. I took the truck for a second spin to see if the transmission would shift smoothly this time, but no luck.


I then brought out the timing light, but before I hooked it up, I decided to check the vacuum for the vacuum advance canister. I have no idea what I was looking for, but I have to say that there was no vacuum pull on the carburetor where I had originally hooked up the line from the distributor. I immediately hooked the line up to another opening which was previously capped off and there was suction there. I unfortunately can't remember what the vacuum reading was. The engine rpm immediately jumped up from 750 rpm to 1,000 rpm on the tach.





I took the truck for yet another spin, but there was no difference in the hesitation and shifting.


I the hooked up the timing light and, try as hard as I might, could not see the indentation on the balancer as the light was flashing. I figured that it the color was just too dark so I tried using some pink nail polish (yes, I borrowed it. Leave me alone. Whatever ), but that didn't do any good. I even sprayed some gold spray paint over the mark but still nothing showed up under the light. So I tried to see if perhaps the video camera or even the boroscope might pick something up, but no luck. And it proved quite challenging to operate two devices at once right over the spinning fan.







Maybe I am just losing my sight. Or is the timing off by so much it doesn't even land on the tab marks? Or is the engine speed to fast for it to be visible, in which case I should retard the timing a bit?

Next on the list: replace the rubber hose ends on the vacuum line to the transmission modulator. Test the modulator.
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  #37 (permalink)  
Old 02-20-2012, 08:01 PM
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If you can't see the mark its either....

Your piece that goes on the plug wire for the timing light is on the wrong wire

or

Your timing is WAAAAAAYYYYYYYY off.

Its not from the engine spinning too fast, I set the timing on my roundy round engine when its at 7 grand...and you see it plenty easy.

another thing to check...

The vaccum connection on the back of the carb that goes to the brake booster. If it is connected tight, and the hose doesnt look cracked...disconnect the hose and plug the vaccum outlet on the carb.

I have seen one or two times where the vaccum booster was sooo worn out that it caused a massive vaccum leak.
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  #38 (permalink)  
Old 02-20-2012, 08:07 PM
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I think you need to get the timing set before you go any further. Have you tried turning the dizzy while running the light to see if the mark will come around? Did you have the light hooked up to the right wire? I have hooked it up to the wrong wire before. How old is the light? You shouldn't have any problems seeing the mark even at 5000 rpms the mark should look like it standing still.
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  #39 (permalink)  
Old 02-20-2012, 08:21 PM
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Hey crussell and BigRoy,

I did not have a chance to turn the distributor while using the timing light because I ran out of time for today. And yes, the wire was the #1 plug wire, with the arrow correctly pointed towards the plug.

The timing light itself is brand spanking new: Equus 5568 Pro-Timing Light with Tool Case

I'm not sure if I mentioned it on this thread, but the distributor did fall off once a few months back, about 2 feet off the ground. Any chance that might've damaged something?


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  #40 (permalink)  
Old 02-20-2012, 10:27 PM
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I was watching the video made yesterday, and noticed that the fast idle cam never dropped.






However, when the movie was made when observing the choke pull off and the fast idle cam, the cam dropped after about two and a half minutes.






I thought the video below had some interesting info. I didn't keep an eye on the fast idle cam today, but will definitely watch it next time when I starting adjusting the timing.






If the distributor turns out to be a problem, I am considering this one from Skip White Performance. The price is very low and the warranty is excellent. Hopefully, so is the performance.

Last edited by lt1silverhawk; 02-20-2012 at 10:41 PM.
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  #41 (permalink)  
Old 02-21-2012, 05:47 AM
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I wasn't able to see the video (problem on my end), does the choke ever completely open?

The timing mark won't be visible if the vacuum advance is hooked up to a manifold vacuum source,

If it was disconnected and plugged, the timing tab/damper line may be off; there were three Gen I tabs/dampers that may be confusing the issue.

DETERMINING TDC will allow you to be sure the timing tab and damper are correctly indicating TDC.

MAKE A TIMING TAPE to see what the total timing is, w/o needing to use a dial back timing light. You can also buy a timing tape, get one that matches the diameter of your damper.

The image shows the correct orientation of the timing tape:


Because the distributor is running the engine, I doubt the drop did any real harm. I would expect a no-start condition if the module or pick up coil had been damaged by it falling. Sometimes modules will run fine cold but give problems when they're hot. The pick up coil can exhibit erratic behavior if the wire inside the insulation is broken from the movement of the advance plate on the distributor.

If you need it:

REBUILD HEI-

HERE'S an exploded view of an HEI distributor.
THIS is a description of an HEI rebuild. HERE is another HEI info/rebuild page.
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  #42 (permalink)  
Old 02-21-2012, 07:05 AM
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Hey cobalt,
Quote:
Originally Posted by cobalt327
I wasn't able to see the video (problem on my end), does the choke ever completely open?
When the truck is first started, the choke pull off starts working immediately, and the choke plate opens up to the 3/4 of the way before coming back up to about half way open a few moments later. However, I can't seem to tell if the choke it self is working (divorced choke). Perhaps if any of the other members can tell, they can chime in.




Quote:
Originally Posted by cobalt327
The timing mark won't be visible if the vacuum advance is hooked up to a manifold vacuum source,

If it was disconnected and plugged, the timing tab/damper line may be off; there were three Gen I tabs/dampers that may be confusing the issue.
The vacuum advance is hooked up on the carburetor. I'm not sure if that could still be manifold vacuum though. I did not disconnect or plug the advance while trying to get an initial timing reading. I will check up on the tab and damper to make sure everything is good there. The timing tape looks like an interesting project to make.




Quote:
Originally Posted by cobalt327
DETERMINING TDC will allow you to be sure the timing tab and damper are correctly indicating TDC.

MAKE A TIMING TAPE to see what the total timing is, w/o needing to use a dial back timing light. You can also buy a timing tape, get one that matches the diameter of your damper.

The image shows the correct orientation of the timing tape:
I did remove and reinstall the distributor several times last year and "found" the TDC by using the timing tab. It was last set at 9 degrees BTDC on the damper (see pages 10 through 13 for reference on that). If need be, I can do so again after making sure the timing tab and damper are ok.




Quote:
Originally Posted by cobalt327
Because the distributor is running the engine, I doubt the drop did any real harm. I would expect a no-start condition if the module or pick up coil had been damaged by it falling. Sometimes modules will run fine cold but give problems when they're hot. The pick up coil can exhibit erratic behavior if the wire inside the insulation is broken from the movement of the advance plate on the distributor.
Yes, there have been no issues with starting. The coil itself was recently replaced a couple of weeks ago. And module "passed" the test at Autozone a few times. If the temperature can be an issue for the module, I think I ran the truck long enough to get it warmed up enough and would have noticed if there were any issues. But I suppose it could be random if the module acts up or not?




Quote:
Originally Posted by cobalt327
If you need it:

REBUILD HEI-

HERE'S an exploded view of an HEI distributor.
THIS is a description of an HEI rebuild. HERE is another HEI info/rebuild page.
Thanks! If it comes down to it, I can take it apart and check everything out. Now I have a better of idea how of the insides work.



Thanks for the continued help!

Last edited by lt1silverhawk; 02-21-2012 at 07:13 AM.
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  #43 (permalink)  
Old 02-21-2012, 12:51 PM
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First let me say I agree that you need to get the timing correct. Second I will say I dont think it is your issue. In past posts you have said that you took it for a ride and sometimes it is fine.
Everything you have posted points to fuel, choke or carburation issues.
In one post you said the choke goes to half way closed then went back to 3/4. This is not right.

I would recommend as your next test you disconnect the choke and wire it open, warm it up and take it for a spin.

Note if the engine is cold it will be hard to start with the choke wide open and you may need to baby the accelerator for a few minutes to keep it running.
If it still runs poorly you have eliminated one thing, the choke. Then move on from there.
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  #44 (permalink)  
Old 02-21-2012, 01:39 PM
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Hey Chet,
Quote:
Originally Posted by T-bucket23
First let me say I agree that you need to get the timing correct. Second I will say I dont think it is your issue. In past posts you have said that you took it for a ride and sometimes it is fine.
Everything you have posted points to fuel, choke or carburation issues.
In one post you said the choke goes to half way closed then went back to 3/4. This is not right.

I would recommend as your next test you disconnect the choke and wire it open, warm it up and take it for a spin.

Note if the engine is cold it will be hard to start with the choke wide open and you may need to baby the accelerator for a few minutes to keep it running.
If it still runs poorly you have eliminated one thing, the choke. Then move on from there.
I will try this the next time I fire it up.


----------


I did make a video of the truck starting and warming up for nine minutes today.



In Case You Can't See the Video:
- Engine starts on the third try.

- Truck is allowed to warm up on its own for the first 8 minutes.

- Choke-pull off closes and the choke plate open up at the 00:15 mark.

- Camera is panned towards the firewall at the 3:45 mark. Light smoke can be seen coming out from the rear exhaust manifold area. Oil seems to be back there. Might explain the fouled plugs on the passenger side?

- Idle cam falls at 8:00 mark when the accelerator pedal is pressed for the first time.

- Coolant starts leaking out of the upper radiator hose at the 8:04 mark. One of the bolts for the water neck wasn't tightened down all the way. Tightened up afterwards.




I then took the truck for a spin on a couple of nearby streets. The video is made from inside the truck and hopefully you can hear the engine hissing and hesitating when gas is given. The video is chopped up to shorten the time.


In Case You Can't See the Video:

- Truck ran under its own power at approximately 20 mph, except when gas given at : 00:14, 00:16, 00:20, 1:23, 1:26, 1:54, and 1:56. Hissing can be heard.

- Truck was parked and revved a three times from 2:20 to 2:43. Engine revved fine, except for the unnoticeable hesitation at 2,500 rpm.

- Truck allowed to run under its own power again. Gas given at 2:51 and 2:59. Hissing heard.

- Truck parked again. Revved at 3:09 mark. Engine revved with the hesitation at 2,500 rpm mark.

Last edited by lt1silverhawk; 02-21-2012 at 01:47 PM.
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  #45 (permalink)  
Old 02-21-2012, 01:46 PM
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Choke is taking to long to open. Do you still have a heat riser valve in the exhaust and is it free. The choke should be fully open in about 3 minutes or so and should never close up while running. It appears in the video yours actually looked like it closed a little a few times during the warm up cycle
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