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Fuel Pump- Part 3

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Thanks Randall, thanks all!!

I guess it's about time I learn to trust my own work.

I just spent two days work chasing after leprecons.
BLARGH!!!!!!!


1. All my fuel lines are spic and span as they were
110 miles ago when I installed them.

2. Carbs dismantled, again, and spic and span as they were
when I cleaned them 110 miles ago. Cleaned again and going
back on the car tomorrow. Not a particle of crud observed.
A very fine hint of color from the brass fittings but nothing
inside when I got them out.

3. New fuel filter with not a spec of crud inside will also
go back into the fuel system.

4. Checked the new dizzy cap and rotor and both look fine.

Back to the diagnostic routine for me next week. I think
I'll start by replacing the coil.

good weekend all,

d
 
sp53 said:
Does your gas tank have an open vent so that you are not creating a vacuum?
Click to expand...

<span style="color: #CC0000">Yup it does and I even opened the gas tank
cap to be double sure no vacuum.

Thanks, good suggestion though.

d</span>
 
Hi Dale,
I haven't been following this saga closely. I don't remember seeing where you actually checked the pump's fuel flow. This is the key to the whole problem.

Disconnect the fuel line from pump to carb at the carb end. Put a piece of flexible hose over the open end of the pump to carb fuel line if needed.

Put the end of the hose in a quart can. Crank the engine over for a timed 30 seconds. If the pump & lines to it are in good condition the pump should put about one pint of fuel into the can. One pint in 30 seconds is equal to 15 gallons per hour which is what the pump should put out. Ten GPH would be acceptable.

If it puts out less, either the feed to the pump is restricted, or drawing air, the pump is defective, or provided it is the correct pump, the pump operating cam on the cam shaft is worn.

When you install the pump on the engine, you should feel some pump diaphram spring resistance as the pump arm meets the camshaft, & before the pump is fully seated to the block. Slight preload. If not, wrong pump, defective pump, or worn operating cam.

If the cam is worn, the simple solution is to install an electric pump & just bypass the mechanical pump. Stop shotgunning the problem & measure the actual flow from the pump. If the pump does put out the prescribed amount of fuel the problem is in the carb.
D
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]If the pump does put out the prescribed amount of fuel the problem is in the carb.[/QUOTE]

Normally Dave, I would agree with you. Perhaps if the volume is good and only because Dale has had an electric pump act the same, there may be an issue with the ignition?

I mean, he's had everything apart and if the flow/volume is good, don't you think that the fuel issue is behind him?

Dale, please consider this my answer to your email as I've been thinking as I read these and I'm not sure where to go. I say that because without being there and listening to the engine, it's hard to tell what is causing the problem.

You mentioned the coil, it's an easy swap, so try it.

Are any of the plugs cracked/fouled?

What color are they?

Have you checked each of the ignition wires for continuity?
 
Just one thing - unless I missed something, this problem is when he drives it? Or is it any time it gets revved?

If the former then surely it has to be some crap left over in the tank getting stirred up and obstructing the flow.

If the latter then I guess it's time to check the timing is right and you have spark...
 
Brosky said:
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]If the pump does put out the prescribed amount of fuel the problem is in the carb.
Click to expand...

Normally Dave, I would agree with you. Perhaps if the volume is good and only because Dale has had an electric pump act the same, there may be an issue with the ignition?

I mean, he's had everything apart and if the flow/volume is good, don't you think that the fuel issue is behind him?
[/QUOTE]
As I said, haven't been following the problem closely. Too many posts in too many places. Reminds me of the monkey trying to put the carrot back in! I couldn't tell if the electric pump was tested under current fuel system conditions. Adequate flow is easily measured, better than a glance & a guess. I'll go back to my hole!
D
 
Tinster said:
Stirkle said:
I believe that there really are bad cars in any make and model. Perhaps this is the TR6 one.

.
Click to expand...

<span style="color: #990000">Ah Stirkle- ever the wise sage.
And I'm with you but I believe there really ARE bad people
in any race or creed. Perhaps you are one.

d :savewave: </span>
Click to expand...

I'm sorry you feel that way whenever anyone asks logical questions about your car problems. I'm white and Catholic by the way, if that matters to you. I'll ask the question in a different way.

Where are the member's that have actually laid their hands on your car? It seems to me that they might have some knowledge having actually seen and driven your car better than those who have not. If you feel that makes me a bad person, so be it.

.
 
Dale - Do I understand that you have a clear glass filter in the fuel line somewhere just before the float bowls ? If so, remove the glass filter and put in a new length of hose. A friend had one in his TR3A with the same symptoms as you describe. It was mounted horizontally up in front of the valve cover and you could see a few air bubbles in it when he started the engine. Then later the accumulation of bubbles increased till he had one large air bubble (like it had become empty of fuel) and there was no flow into the carbs. He had no dirt in the system, only air.
 
Dale
My TR6 left me on the side of the road, actually in the middle of the the road on a very wide concrete curb, it started sputtering badly and before I could get home it died, I pulled the coil wire and grounded it and I had fire, I didnt have a spare spark plug to test individual cylinders until I got it towed home, but turned out the dist cap was bad, replaced it and no probkem now, you couldnt tell by looking at it that it was bad either. Not saying thats your problem just something else to check

Hondo
 
hondo402000 said:
Dale
My TR6 left me on the side of the road, actually in the middle of the the road on a very wide concrete curb, it started sputtering badly and before I could get home it died, I pulled the coil wire and grounded it and I had fire, I didnt have a spare spark plug to test individual cylinders until I got it towed home, but turned out the dist cap was bad, replaced it and no probkem now, you couldnt tell by looking at it that it was bad either. Not saying thats your problem just something else to check

Hondo
Click to expand...

<span style="color: #990000">Thanks Hondo-

My dizzy cap and rotor both brand new with maybe
40 miles on them. I looked at them briefly but will make
a closer exam.

I'll try to locate a fuel pressure test rig today
but being Fathers Day weekend, the stores are mobbed.

I hope to have the carbs and everything back on the car
by late afternoon.

It really is a puzzle given that everything except the
long block is new or professionally rebuilt with less
than 1700 miles on them. Maybe the timing chain is the problem

thanks,

PS: Dave - that pint/30 seconds sounds like an easy test to
perform: I think I'll try it. Thanks

d</span>
 
I drove Amos at Christams last year. This was before the bad gas incident. It drove fine. So I am inclined to stay with the fuel delivery theory!
 
angelfj said:
I drove Amos at Christams last year. This was
before the bad gas incident. It drove fine. So I am inclined
to stay with the fuel delivery theory!
Click to expand...


<span style="color: #000099">I'm just back from purchasing a vacuum/fuel
pressure gauge. Now put the car back together and test
the fuel flow.

Yikes!! some major event has happened in the past 39 miles.
As suggested, I just pulled two plugs expecting the normal
pale,toasty brown color. 39 miles ago these plugs were clean
back to white. Here is a today photo and a photo just BEFORE
I cleaned them back to white.

Something radical has changed in the past 39 miles.
Any suggestions appreciated. I'm putting the carbs and
fuel delivery system back together.

New dizzy cap and new rotor and cleaned plugs. Nothing
else was changed or adjusted. Yes, I checked, the firing
order in correct. Lucas Sport coil and gap of 30 feeler
gauge.</span>

blackPlugs.jpg


plugRotor.jpg
 
Definitely running rich or misfiring. How did you clean the plugs? A wire brush will leave metallic tracks on the insulators of the plugs causing shorting and misfiring.

Were the plugs running clean after you removed and cleaned the carbs?

Could the float level have changed while you were cleaning the carbs?

Did you use the same sealing washers under the float valves, if there were any?

How is it running now at higher revs?

What is the fuel pressure? If it has increased too much, the extra pressure can blow the fuel past the float valve, causing rich conditions.

Are the choke/s stuck on or out of adjustment?
 
startech47 said:
Definitely running rich or misfiring. How did you clean the plugs? A wire brush will leave metallic tracks on the insulators of the plugs causing shorting and misfiring.
<span style="color: #CC0000">might be it! brass metal brush and 400 wet paper. I'll install new plugs right away</span>

Were the plugs running clean after you removed and cleaned the carbs?<span style="color: #CC0000">yes they were</span>

Could the float level have changed while you were cleaning the carbs?<span style="color: #CC0000">very doubtful</span>

Did you use the same sealing washers under the float valves, if there were any?<span style="color: #CC0000">no, new ones</span>

How is it running now at higher revs?<span style="color: #990000">falls apart at 1500 rpms and above</span>

What is the fuel pressure? If it has increased too much, the extra pressure can blow the fuel past the float valve, causing rich conditions.<span style="color: #CC0000">just bought the gauge</span>

Are the choke/s stuck on or out of adjustment?
Click to expand...
<span style="color: #CC0000">chokes are just about perfect

thanks for the advice.

dale</span>
 
Did you check the float valves ? Crud from the fuel system can get caught inside the valve, causing it to leak and run the mixture way high at idle.

I wound up having to replace the float valves on my Stag, because they wouldn't seal properly.
 
Dale, your car is reminding me of an episode of House, MD. All these symptoms and we can't figure out the ailment. Great show by the way if you've never seen it.

Thoughts I've had regarding your fuel system:

Eliminate the fuel system. Hook a direct feed from a 5 gal. gas can to your carbs and see if the engine runs. If yes, hook up the fuel pump, run a line from the can to the pump. Repeat. If it runs, go back step by step until you get to the gas tank. Always use the can for your fuel source. If the block is in one of the stages, you'll find it. Otherwise you'll know it is in the tank. I keep thinking about that glass of nastiness you got out of your tank. Is it possible it mucked up or melted any of the rubber bits in your pick up in the tank? Is your gas cap vented? Once you've done this, you'll either find a cause or know for certain the fuel system is not the culprit. Then you can turn to the ignition or carbs.

I admire your tenacity for seeing this through and feel your frustration in not being able to get this figured out!

Take it one piece at a time.
 
<span style="color: #000099">Progress report noon-island time:

Carbs and vacuum lines back on the car. I attached
the fuel pressure meter into the fuel line just
before the carbs. I disconnected the coil and cranked
the engine for 10 to 15 seconds.

I got 1.6 psi on three separate measurements.
I disconnected the gauge during one test and gasoline
spurted out in uniform pulses (gushes).

Taking the Mrs to the panaderia for lunch.

Tata and thanks for the advice. We've tamed this wicked
Beast before and the BCF will tame it again. The ghost
of DPO Pedro might be haunting us be we'll BUST him good
as always!!!!!!!!!!!!!!!

dale</span>

<span style="color: #990000">Edit: Pondering the black plugs.
I added 2 or 3 ounces of 2-stroke engine oil to my 10 gallons
of high test fuel; in order to help cut down on tank rusting.
I wonder if the 2-stroke oil blackened my plugs? They DO look
kinda oily not sooty.

Just a thought.</span>
 
Update 2:45 PM Sat island time

Everything back together, cranked up fairly easily but
now idles at 500 rpm while it was at 800 rpm before
taking everything apart. I could not get idle up any
higher with an entire turn of the idle set screws.

No. 4 plug seems to miss from time to time- according
to my timing light.

Timing checked - at a sloppy 12 degrees due to low idle.

The engine still falls apart at 1500 rpm or higher.
No change at all after removing and cleaning the complete
fuel delivery system

I'm fairly certain now I have clean fuel lines and
clean carbs with a clean fuel pump putting out 1.6 psi.

Now, I'll install new spark plugs and work my diagnostic
way backwards from the spark plugs thru the ignition system
to the alternator.

BLARGH!!!!!!!!!!!!!!!!

d
 
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