# Out of fuel, but how?



## leeklm (Mar 11, 2012)

Here is one that has me stumped... I actually read a similar post a short while back, but could not find it now.

Engine will "sometimes" cutout at high RPM like you shut the fuel off, usually around 4K or so. The enigne quickly recovers when you let out of the gas. This has happened on two different motors, two differnt qjets, and two different high-flow fuel pumps. I have not been able to repeat the problem using two different Holleys.

I have replaced the 5/16" rubber line by the tank, and have a newer 3/8" steel line running up to the pump, and a 3/8" steel line up to the carb. I can disconnect the line at the carb, and gushes out enough fuel to feed a 1000hp engine!

This is difficult because it is not consistant. I can run through the gears up over 5k without missing a beat. A few miles later, I can casually get on the gas to run up the RPM (like to pass a car), and will get the high rpm cut-out. It happened today with my fuel level running low, but it also happened a couple of weeks back with a full tank.

Previous ownner installed a new tank, so I pulled the sending unit to look at the sock. It was clean, but looked old and was starting to split apart. One thing I noticed is that the sock had a sharp bend to it, only about an inch up from the pickup tube. I started to wonder if this was in effect pinching off the sock, forcing all the fuel to feed through a small portion of the sock? Anyhow, will be ordering a new sock.

I am assuming the holleys never had the problem since they would have plenty of reserve in the two fuel bowls. 

I read another post talking about potential problems from a non-vented tank, but mine does have the vent tube installed at the neck.

Any thoughts on this one guys?


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## 05GTO (Oct 6, 2004)

It may be a problem with the mechanical advance, a fuel problem or vapor lock would not recover that quickly. You would be able to run thru the gears without problems because the engines vacuum is enough to maintain the advance, but when cruising the engines vacuum will go to zero and the engine then runs off of the mechanical advance. Best way to test is to connect a timing light, remove the vacuum advance and see if the timing changes while reeving the engine,


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## BearGFR (Aug 25, 2008)

leeklm said:


> ... It happened today with my fuel level running low, but it also happened a couple of weeks back with a full tank...


That's a clue. You're running a "big" engine if I remember correctly, right?

You've got several things working against you. One is the 'small' 3/8" fuel line, another is having the fuel pickup in the factory location, another is the QJet itself (has a small fuel bowl so supplying enough fuel to keep it full is both critical and difficult), another may be fuel pressure to the carb (have you checked it?)

With a QJet because of its relatively small fuel bowl, you have to walk the razor's edge on input pressure - keeping it as high as possible without it being high enough to force the needle off the seat and cause uncontrolled flooding. That's usually somewhere "around" 6 to maybe 7 psi, depending on which float and needle/seat you have. Of course what really matters is volume, not pressure. A larger cross-sectional area line is going to supply more fuel volume at the same pressure than a smaller cross-sectional area line. Equal pressure working on a 1/2" line is going to move more fuel than the same pressure working on a 3/8" line. 

The problem with the factory fuel pickup is that it's in the center of the tank. Under hard acceleration all the fuel will stand up in the back of the tank, uncovering the pickup so that it just sucks air. 

Then there's the pump itself. It's a long way from the pump to the tank, and having to "suck" all that volume/weight of fuel in the line forward while the car is accelerating hard is a big challenge. Yeah, the pump might flow like gangbusters while the car is sitting still, but when that famous Pontiac torque kicks in it's going to be a different story. Gasoline weighs about 6 lbs. per gallon. Say there's what... probably at least a half-pint of gas in a 3/8" fuel line between the pump and the tank? Work that out and it's somewhere in the vicinity of 1/3 of a pound. Try accelerating a 1/3 pound weight _faster_ than your car is accelerating (so it can keep a positive fuel flow) using nothing but suction. It ain't easy.

Also make 'the usual' checks. If you have any 'rubber' hose anywhere in the system, make sure none of it is cracked or leaking - not necessarily enough to physically leak fuel but enough to allow the pump to 'suck air' into the line.
Check all your filters to make sure they aren't clogged at all. 

Put a fuel pressure gauge on so that it reads pressure going into the carb. If you mount the gauge so that you can read it while driving, either keep the gauge _outside_ the passenger compartment or use an electrical gauge with a remote sensor. You never want any arrangement that puts pressurized fuel anywhere inside the passenger compartment, even if it's inside a line. If you see pressure dropping below 6psi "or so" under heavy acceleration, that's pretty conclusive that your pump and/or fuel line just isn't up to the task, or you've got a clog/leak somewhere (or both).

Bear


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## Chris-Austria (Dec 23, 2010)

Thats an interesting topic, if you don't mind I also have 2 questions:

1. with the same pump but a 1/2" line instead of the 3/8" will the fuel pressure be the same?

2. if there is a bigger line between the tank and the pump (which contains more fuel) will the difference in weight make a difference during hard acceleration because it has to pull even harder?!


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## BearGFR (Aug 25, 2008)

1) Depends on if you're talking about output pressure to the carb or "input pressure" (actually a pressure drop) into the pump.

2) Remember what matters to your engine is volume, not pressure. 

Actually, the term "suction" is somewhat misleading. Remember from your high-school physics class that matter in liquid state is essentially non-compressible/non-expandable. What actually makes the fuel move in the line is air pressure. There are two (or two sets) of one-way check valves in the pump chamber. One set of valves only allows fuel to flow into the chamber (from the tank side), the other set only allows fuel to flow out (to the carb side). When the pump diaphragm moves "up", it's trying to expand the volume inside the pump chamber. The liquid fuel (being non-expandable) resists that idea vigorously, so something else has got to give. That 'something' is going to be in the form of the path of least resistance. In the case of our fuel pump, hopefully that's going to come in the form of atmospheric air pressure inside the tank pushing on the fuel, causing it to flow into the fuel line, opening the 'input' check valve in the pump, and flowing more fuel into the pump chamber to fill the volume. That's why any sort of air leak in the line has such a bad effect on fuel flow - air is easier to move and lighter than liquid, so an air leak in the line (especially one close to the pump will allow air into the pump chamber to fill the larger volume without moving as much (or maybe any) fuel movement. If you envision a completely air-tight and leak proof system from the tank all the way to the pump chamber, and remember liquid is not compressible/expandable, then what actually makes the fuel move is the air pressure inside the tank pushing on it when the pump makes its up stroke. It's also why the tank air vents are so important - they allow more air into the tank to push on the fuel. If the tank were to be completely air tight with no air inside, there would be no flow. What would happen would be that the outside atmospheric air would push on the surface of the tank and it would flex in and out in rhythm with the pump in order to keep total volume (which includes the volume inside the pump chamber, the fuel line to the tank, and the inside of the tank) constant. With some air in the tank, but still no vent, you'd reach a point where the air pressure in the tank would pulse down and up with the pump stroke but there still would be no fuel movement. 

Moving on to the carb side of the pump diaphragm, when it pushes on the fuel, the fuel (again being non-compressible) really objects to this decreasing volume and shows its disdain for the goings on by leaving -- through the output check valve and through the line to the carb where it gets rude and pushes on the air inside the carb and makes some of it leave through the carb's bowl vents.

Air of course is elastic, has mass, and also has inertia so it too resists moving - but it generally loses the battle and has to move because it IS compressible and expandable, and has less mass than the other things involved in the whole shebang. 

Think about how a pressure gauge works. You've got an orifice, leading to a sealed diaphragm, connected to a mechanism that registers movement of the diaphragm as a movement on the gauge needle. When that needle swings, what it's really telling you is that the volume inside the area from the orifice to the diaphragm has gotten larger because something has pushed on the diaphragm and made it move, overcoming its preference to stay in a certain spot. When the gauge registers zero, it really means the volume inside the gauge chamber has returned to the point where the gauge "likes it", either because of a spring or the natural springiness of the diaphragm itself being stronger than anything that might be pushing on it.

Ok, now that I've taken a detour around the other side of the world through parts unknown, let's get back to your questions.

Pump output pressure is going to be affected by whatever is present in the output side of the pump that resists fuel movement. Ideally it's mostly the size of the orifice in the carb needle valve. The pressure is also affected by how much the pump diaphragm is trying to change to the total volume in this side of the system on the down stroke. If there are leaks anywhere (less resistance to movement) pressure is going to drop. if there are additional restrictions to movement (clogged filter, too small of a feed line, spec of dirt in the needle seat) pressure can go up while volume of fuel delivered will actually decrease. Changes to the volume of fuel in the pump chamber can also cause a pressure drop (even if there are no additional restrictions on the output side). How? from restrictions on the input side. Why? remember the pump diaphragm is elastic. If there are restrictions (resistance to movement) on the input to the pump then the pump diaphragm on the upstroke won't be able to increase the volume in the chamber as much as it "wants" to. Instead it will be forced to deform/stretch/"balloon" downwards into the chamber some and maybe there might be some air forced to leak past the edges of the diaphragm (maybe both) - and because of that there won't be as much fuel entering the chamber through the check valves - and therefore less fuel to deliver on the next down stroke. All this happened because the restriction in the pump feed line from the tank was working against the atmospheric air pressure in the tank that was try to push fuel through the line and into the pump chamber. That's going to show up as a pressure drop on the output side also.

Interesting stuff....

Bear


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## leeklm (Mar 11, 2012)

Thanks for the good info. While I am using the same distributor on both engines, the advance moves smoothly up through the RPM band with full mechanical coming in about 2,800. The HEI also worked fine at engine dyno, and with the Holley.

Correct Bear, this is the new 455, but had the same occasional issue on the smogger 400 last year with a different qjet. I was playing around at the time with float level trying to correct the problem.

Since I have 3/8 line running the length of car, I am thinking of replacing the stock pickup with a 3/8 unit instead of 5/16. Need a new sock anyway, so what is another $40 in this money pit :confused

I had a fuel gauge on the Holley dual line feed, which would read 6-6.5 LB with the Holley mechanical pump, and the new pump I bought from AMES. Not sure of brand, but sold as high volume, and looks similar to the Holley. I like the idea of installing a gauge I can read while driving. If the new pickup & sock does not help, that will be my next move.

Since a 67 GTO would have had the same fuel/tank setup and lines with a Qjet, would they not have had similar issues when the car was new?

I will keep you posted with the results!


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## BearGFR (Aug 25, 2008)

Maybe, but that big inch motor with the other good parts on it you have is going to need more fuel than a vanilla 67 400 would. 
If you're going to change the pickup, check this one out:
RobbMc Performance Products - GM 1/2" Sending Unit

Next step would be to upgrade the whole fuel line to 1/2", but that's a tougher job. I'm glad I went that route with mine. I had InLine tube make me up a 1/2" stainless line bent to run in the factory locations.

Bear


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## xconcepts (Jan 4, 2009)

Sounds like the exact problem I have. I can stomp on it and at high RPM's it sputters and I have to back off. If I ease back on it its ok. I've switched out the fuel pumps, filter, sock and all the fuel lines. And it was never low on fuel. 

It seemed to fix it for a little when I went from the 4 brl to the tripower and replaced the fuel filter, but then went right back.


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## swaayze (Jan 10, 2013)

Is the rubber line from tank to hardline crimped at all? Perhaps the fuel flow is somewhat restricted and ok at low demand but compromised at higher needs. My hardline slipped down and further crimped the rubber line and cutoff the fuel flow to the pump the other night after I replaced the hose. The old hose was firm though slightly crimped but the new one is more susceptable to closing off more.


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## leeklm (Mar 11, 2012)

No, in my case the rubber line that was replaced looked ok. I liked Bear's fancy 1/2" fuel pickup, but I went cheap and ordered the $50 3/8" pickup. Should have that in this weekend, and will see how it goes.


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## leeklm (Mar 11, 2012)

xconcepts said:


> Sounds like the exact problem I have. I can stomp on it and at high RPM's it sputters and I have to back off. If I ease back on it its ok. I've switched out the fuel pumps, filter, sock and all the fuel lines. And it was never low on fuel.
> 
> It seemed to fix it for a little when I went from the 4 brl to the tripower and replaced the fuel filter, but then went right back.


Wow, with 3 fuel bowls in the tripower, you would think there is plenty of fuel on reserve it would be easier for the system to keep up on a short burst? In my scenario, the problem never presented itself with the Holley, which I assume is due to the extra fuel available in the 2 bowls.


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## xconcepts (Jan 4, 2009)

leeklm said:


> Wow, with 3 fuel bowls in the tripower, you would think there is plenty of fuel on reserve it would be easier for the system to keep up on a short burst? In my scenario, the problem never presented itself with the Holley, which I assume is due to the extra fuel available in the 2 bowls.


yeah, I would have though the same. I'm stumped, I had a video but must have removed it and can't find it anymore. I'm really hoping that having the engine being rebuilt at them moment will fix whatever was wrong...


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## etewald (Dec 27, 2011)

Ok, I'm having the same problem with my '69. 400 Qjet, TH400, newly rebuilt carb, new mechanical fuel pump, new fuel filters, new soft lines between tank/hard line, hard line/pump and pump/carb. 

Initially(and the thought still lingers), I thought it was the timing. So I put a light on it, and initial was at about 4 below TDC. I moved it up to 6-7. With the advance hooked back up and revved to about 2500, total timing was right at 36. Took her out and nothing changed. She idles great, will bark the tires in 1st and 2nd, but if she's in 2nd or 3rd and I hammer it, she'll kick down, then sputter like there's no fuel and about a quarter of the time, she'll die completely. If I let off when she sputters, half the time when I reapply pedal, she'll still cough and sometimes die. 

As I inherited the Goat when my brother passed away a year and a half ago, I'm not sure how old the distributor is, but it looks pretty new, as do the plug wires. 

The only other thing I can think is that the linkages on the carb aren't quite right, and the secondaries aren't opening all the way up under WOT. Kinda pulling my hair out, and will be more so over the next few weeks as the weather turns really nice and the Goat is in the garage.


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## BearGFR (Aug 25, 2008)

etewald said:


> ... With the advance hooked back up and revved to about 2500, total timing was right at 36. ...


That's probably not enough. You should set it to 36 degrees using that same procedure at 2500 rpm, but with the vacuum advance disconnected and plugged. Why? Because what you're trying to do with this procedure is to set total ignition timing that the engine will see _under load_ - wide open throttle - and at WOT there is no manifold vacuum to speak of. So, by setting it the way you did with vacuum connected, at WOT (when your engine isn't making any vacuum) it's going to be getting less than 36 degrees (maybe a lot less). Pontiacs with open chamber iron heads tend to "like" about 36 totlal (total in this case meaning total advance under load at WOT). I think that word "total" is what throws people off and makes them think they're supposed to set it with everything connected. In reality, under cruise conditions (part throttle, light loads) your engine is going to run "happier' with quite a bit _more_ than 36 degrees --- that's what the vacuum advance mechanism is really for: to add more timing under part throttle cruise conditions.



> The only other thing I can think is that the linkages on the carb aren't quite right, and the secondaries aren't opening all the way up under WOT. Kinda pulling my hair out, and will be more so over the next few weeks as the weather turns really nice and the Goat is in the garage.


Get the ignition timing right first, then see where you're at with it. Lars on here has a good writeup on tuning the QJet. I've got a copy I can send you if he doesn't chime in. Also find yourself a copy of Cliff Ruggles's book on the subject, "How to Rebuild and Modify Rochester Quadrajet Carburetors".

Bear


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## etewald (Dec 27, 2011)

So with the vacuum disconnected and plugged, I should be at 36 below TDC? I don't know if it'll stay running with that much timing. I guess I was doing it all wrong, because at regular idle there's no way it could handle that much timing. I imagine at 2500 she might though. I'll head out and try it this afternoon if all goes well.


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## BearGFR (Aug 25, 2008)

Well, 36 degrees at 2500 won't be near that much at idle, because at idle the centrifugal advance weights/mechanism in the distributor will not have "kicked in". Before you start adjusting things, do this:
Disconnect the vacuum advance, plug the hose.
Check with your timing light to see what the initial is set to right now just to get a reference number - make a note of what it is.

Then, have a friend take it up to 2500 and hold it steady there (vacuum still disconnected and plugged).
Set timing to 36 degrees (engine still steady at 2500).
Tighten the clamp, check it again at 2500 to make sure it didn't move - repeat till you get it locked in and it's right.

Check it again at idle (still disconnected and plugged) to see how much this reading changed. Now you also know where you need to set it _at idle_ in the future in order to return to this setting (as long as you keep the same distributor and don't modify the internal advance mechanism -weights, springs, stop bushing).

Re-connect everything (vacuum advance) - take it out and drive it for an evaluation.

Bear


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## 05GTO (Oct 6, 2004)

JMHO,
In addition to Bear's comments here are a couple articles on timing, I would work on getting the timing right and if that doesn't correct the problem then go back to the fuel as being the problem.

Timing Advance Curve Basics

Changing the Advance Curve on HEI Distributors


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## Rukee (Feb 8, 2007)

I wish I could run 36* timing!! The only time I can is running racing fuel. Other then that I run at 25* total advance and still have some slight pinging at WOT.


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## BearGFR (Aug 25, 2008)

Rukee said:


> I wish I could run 36* timing!! The only time I can is running racing fuel. Other then that I run at 25* total advance and still have some slight pinging at WOT.


Must be running some compression 

I'm running 39 degrees in the Beast, 19 degrees initial. But then that's with aluminum heads and 10:1 (because of the aluminum heads). When I had cast iron on it, it was at 9.4:1 and running at 35 degrees (which is what the chambers in those heads liked the best.)

Bear


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## Rukee (Feb 8, 2007)

Yeah, it's the factory 10.75 compression and then bored 60 over. At least I have forged pistons. :cheers


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## leeklm (Mar 11, 2012)

Ordered the 3/8" fuel pickup & sending unit last weekend, expecting to have it by today. However, my Pontiac parts supplier did not ship it and the other parts I ordered until Wednesday! 

Since I "needed" to drive the car this wknd, I installed my old pickup with no sock, not too worried about plugging up the filter since it is a newer tank. Maybe just coincidence, but worked great the couple of times I got on it. As mentioned earlier, the old sock seemed like it was pinched off/bent over just after the pickup tube, so I am holding out hope the problem is something this simple!

Also interesting how much more "crisp" the engine is today with cool dry air outside. Very dry and in the upper 50's. I had my new wideband A/F gauge running about 14.4 at cruise during my last outing, and today was hitting 15.0 pretty easy at cruise speed. Backed the APT out a half turn to bring the A/F down a bit.

I have a feeling this new A/F toy will be fun & educational, but I will be wearing out the hood hinges making constant changes to the carb :willy:


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## leeklm (Mar 11, 2012)

quick update... installed 3/8" pickup and new sock, so entire fuel line is now 3/8 up to the carb. made several runs this evening and no high rpm issues!


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## Rukee (Feb 8, 2007)

:cheers


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## leeklm (Mar 11, 2012)

Not so fast... As of my last post on this topic a month ago, the car was running fine with no high RPM out of fuel symptom, which even included a couple of runs down the drag strip.

I replaced my Hyd Cam with a solid lifter higher duration cam last week, and everything was still fine. Engine would pull up to 5,500 with no issue.

Well, tonight I was on my way out with the wife, filled up the tank, and the car does it again! Exact same symptom as before. The car sat for a few hours, and drove home, wound it up again to 5,500 rpm and No problem, everything seems fine. 

I am stumped.

While this feels just like a fuel starvation problem, I am tempted to replace the HEI Distributor, which is the only piece left not changed since this cropped up over a year ago. Not sure what it could be though, because the pickup coil and other components had been changed as well. I just wish the problem was a little more consistent so I could troubleshoot it a little easier!


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## geeteeohguy (Feb 2, 2008)

How hot was the ambient temperature? You _could_ be experiencing vapor lock/fuel percolation issues with the new poor fuels. Tends to happen after a heat soak period on warm/humid days or nights.


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## leeklm (Mar 11, 2012)

Good point geetee, and something I thought of as well. In this example, I filled the tank, drove 2 miles and stopped at the parts store for maybe 10 min. Got on road, stepped on it and had the high rpm stumble. It was 90 and humid. Car sat for another 15 min, was able to repeat problem showing the car off to my cousin. It then sat for about 4 hr temps cooled to about 75 and all was good. 

In the past, temps did not seem to matter. Come to think of it, I was using my expensive real lead octane additive recently, but did not on the last tank... hmmm could the additive have any impact on fuel boiling?

I do have a wrap on the steel fuel line from where it exits frame up to the carb to help insulate it some.

Sent from AutoGuide.com Free App


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## geeteeohguy (Feb 2, 2008)

Yes, the new fuels are so volatile that they boil in the fuel lines very easily. I had your same issue for a long time, and a combination of things fixed it for good: good fan, good fan shroud, the proper steel heat block-off plate under the carb, and mostly, my re-install of the stock fuel vapor return system that I had disconnected years before in ignorance. If it doesn't do it in cooler weather or conditions, you can be pretty sure your fuel is percolating in the lines and causing your problem.


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## leeklm (Mar 11, 2012)

Drove the car 100mi to the strip yesterday, made 3 runs winding it up to 5,500 and ran absolutely perfect.

I am beginning to think that although the symptoms were similar, I am really looking at two separate issues. I am convinced that the first out-of-fuel stumble I dealt with for months under many different weather conditions was related to the fuel pickup. Once that was replaced, no problems at all until a really hot & humid day. In that case, I am thinking it was likely fuel boiling.

Time will tell...


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## geeteeohguy (Feb 2, 2008)

Your recent racing activity and the resulting performance is a pretty good indicator that nothing is fundamentally mechanically wrong with the car. I would bet it's a fuel or weather induced situation. Could have been some very poor fuel, or the climate, etc.


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## xconcepts (Jan 4, 2009)

So even after the rebuild I am having the same issues. I am wondering if I should go to the 3/8" pickup? Again all stock besides the pentronix unit in the cap instead of the points. Everything has been replaced within the last year, plugs are new as of a month, plug wires less than a year old, fuel pump the same...all rubber lines have been replaces as well. But I'm not sure if what size the original fuel lines are. 

The only other thing I can think it might be is a bad/going bad pentronix unit. Never had the problem with the points system and don't remember if it started after I went to it.


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## Rukee (Feb 8, 2007)

Just had this issue with a `69 Cougar I'm working on, do you have the red wire for the Pentronix unit connected to full 12v supply and not through the resister wire?


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## xconcepts (Jan 4, 2009)

Rukee said:


> Just had this issue with a `69 Cougar I'm working on, do you have the red wire for the Pentronix unit connected to full 12v supply and not through the resister wire?


Yep, double checked the wiring when we reinstalled the engine after rebuild. Just needs a hot ignition wire IIRC right?


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## Rukee (Feb 8, 2007)

It needs a full 12v. This Cougar has a resister wire so at the coil is only like 8.5v, and it ran like dog meat. Attached the red wire at the firewall with full 12v and it runs perfect now.


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## xconcepts (Jan 4, 2009)

I will check it tonight to make sure its 12v, runs fine besides getting on her as the OP was having the same issue.


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## geeteeohguy (Feb 2, 2008)

I've said this before, and I'll say it again: usually when there is a problem, it is with the part of the car that was 'upgraded' to an aftermarket part. This is true about 99% of the time. I wouldn't run anything but the stock points distributors in my cars. Been doing it for decades without a problem....no reason to change, as reliability is at the top of my list.


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## Rukee (Feb 8, 2007)

geeteeohguy said:


> I've said this before, and I'll say it again: usually when there is a problem, it is with the part of the car that was 'upgraded' to an aftermarket part. This is true about 99% of the time. I wouldn't run anything but the stock points distributors in my cars. Been doing it for decades without a problem....no reason to change, as reliability is at the top of my list.


I totally agree, with the exception that I run an MSD 6AL unit with the stock points system, which only reads the points like an ohmmeter, not with voltage so the points last forever and you get the benefit of multiple spark and a rev limiter.


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## xconcepts (Jan 4, 2009)

so I tested voltage at the coil, it was jumping around and never consistent. It would be around between around 8 volts jump to 30 volts and drop back down 8 volts. would I be better off just going back to the point system instead of the pentronix unit? I'm all stock anyways but I thought that unit would be better for the engine


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## geeteeohguy (Feb 2, 2008)

That's what I would do. The electronic ignitions are excellent, usually. Thier advantage lies in no maintenance. Until they fail, which is often enough. Points distributors typically need a new set of contact points every 15,000 miles or so. So, you need to maintain them. Part of the experience of having a classic, IMO. How many miles do you drive it in a year? If you're typical, a set of points will be maintenance free for YEARS.


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## xconcepts (Jan 4, 2009)

I am no where near 15k in 5 year so I'll look into points again and seeing if it works. First going to find a good 12v for this pentronix though and see if it fixes my issue. Am I wrong in connecting to the coil for this ignitor and there is also 2 other lines going to it.


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## Rukee (Feb 8, 2007)

Try connecting the red wire directly to the battery positive and see if it runs better.


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## leeklm (Mar 11, 2012)

If you do not have a tripower, I have always been a big fan of HEI, maybe because it is what I "grew up with". You do have the "module" and pickup coil that can go bad, but easy to diagnose, and no points to adjust  But either HEI or stock points will be more reliable than most of the aftermarket stuff!


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## xconcepts (Jan 4, 2009)

I have a tripower, it did the same thing with the 4brl as well though. Again I believe it started after I switched to the pentronix unit though. The coil is brand new as well.


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## Rukee (Feb 8, 2007)

xconcepts said:


> I have a tripower, it did the same thing with the 4brl as well though. Again I believe it started after I switched to the pentronix unit though. The coil is brand new as well.


Have you tried to hook the red wire up directly to the battery for a test drive?


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## xconcepts (Jan 4, 2009)

Appears hooking right to the battery works, would there be an issue leaving it hooked directly to the battery?


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## xconcepts (Jan 4, 2009)

Anyone on if I'm ok to leave direct connected to the battery?


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## gjones (Oct 8, 2012)

*tap*

I don't believe that I'd leave it hooked directly to the battery, as you're libel to burn out the pickup, (at the very least). You'd want to at least have it ignition fused (not acc) to shut the power off when not being used. Should be easy enough to stick a cheap relay on that circuit, or tap into the ignition circuit.


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