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TR2/3/3A little miss problem

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sp53

Yoda
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Well I had this little miss problem that I could not find and after changing, coil, points, plugs, carb needles and seat plus the fuel pump, I am toast. Anyway it is starting to look like the gas tank itself is old and flaky and rusty and dumping the crap on and off--- plus in chasing this miss I filled the tank with gas from a different station. I blew air back through the tank to perhaps move the crap around, but now it looks like my back up fuel pump is out also. Any ideas on how to maybe partially drain the tank for a quick fix or something or do you guys suggest draining the tank and starting out clean. I am open for ideas--- we are having a heat wave, and I cannot think or I am over the hill or something.
steve
 
One of the little Facet electric pumps hooked to a battery charger makes a reasonable (tho slow) transfer pump. Put a filter in the line and pump the excess fuel into your family grocery getter.

But I doubt that is the problem. In my experience, dirty fuel is either no problem at all, or a lot bigger than a "little miss". Those SU carbs are remarkably insensitive to crud in the fuel, but when they do have a problem, they either dump fuel all over the place or don't run at all. And anything that makes it past the screen in the stock pump will usually just get sucked through.
 
I removed my tank to clean it out with a product called "Crud Cutter" which was a mistake because after I reinstalled the tank the product continued to flake off black crap from inside the tank. I'm running an electric fuel pump located under the frame below the drivers seat. I installed an inline fuel filter before the pump that stops the black crap from getting to the pump and carbs. I check the fuel filter every now and again and replace it when it looks too full. There is a type of clamp that you can get to clamp the rubber fuel lines to make changing the filter easier. I keep several spare filters in the boot. Hopefully the tank will eventually clear itself of crap. Didn't want to pull the tank all over again.
 
I was not clear you guys the miss has turned into a no start while at first it would start right up but miss at 4K in 3rd gear then a miss 2nd at about 3K to a miss going down the road and around the block in first. But again I have done so much adjusting I kinda lost my base line.

Last night I swap out the pump with a different pump, the car fired right and ran great for about 2 minutes then just stop. I checked the pump and it was not pumping, but the bowl was fuel. I thought the line plugged from crud, but I pulled it and it drained fine with gravidity. I wonder if those valves on top of the pump are clogging that fast? I hear you Randall usually a fuel filter on SU with an old tank is the problem because it clogs up, where as with no filter, the dirty fuel goes right through the system.

David I might try your idea to be sure. Karl I have heard many stories about fixing the inside of a tank from an acid bath and putting a bunch of old nuts and bolts then shake it around then drain it out then put some sealer in, but I have never tried it. It sounds like you need to do something also with a fuel delivery problem. I would like to buy a new one from the big 3, but I need to manage the money on the rebuild better. I do have another tank that should work.

I might just hold off until the Saab is low then pump it over like Randall suggested because I would hate to get it running and then get stuck ,and on the other hand I do not want to kill the Saab, but I guess if I held the hose towards the top while I was pulling out the gas things should be ok. My but is kicked.
steve
 
Is the metal screen in place in the area above the fuel bowl? That should catch crud before it goes into the fuel pump valves. But the screen can easily get plugged.
Charley
 
bobhustead said:
Before delving into tank rehab, you should try rotor, cap, plug/coil wires and condenser.
Bob
Click to expand...

I have a friend who has the motto "it's always ignition". If you are getting a lot of crud in the bottom of the glass bowl, then I'd continue to pursue the fuel side of the equation. But, your description also sounds a lot like a coil that breaks down as it heats up.
 
Yes that is my motto also John. The pump had a lot of crud in the bowl-- perhaps a 3/8 at the bottom and the back carb had lot in the top filter and float bowl. The stuff must come through in small pieces and then re-configurator because it looks like chunks until I squeeze it between my fingers and then it like fine powder. I switched the coil but might still try another one; I have a collection. Today I am going to rebuild a pump and put it on, so I know for sure the pump is good because this one stopped puming. The one I put on had the staked in valves but a new diaphragm. I bought it on eBay in grab bag and through it together with kit it came with thinking it would work. I have a collection of old pumps in attic and today I am going pick through and get a nice top with screwed in valves replace them new before I mess with a full tank.
steve
 
OK...if you are seeing that much junk in the bowl, then it's likely that dirty fuel is clogging everything and causing the miss. If you are not up to cleaning out the tank now, then maybe keep a large filter on the intake side of the pump and change it regularly until the junk in the tank either empties out or settles back down?
 
Steve ,
if you have crud in the float bowl, then you also need to check / clean the float bowl valves found in the top of the float bowl lid. It does not take much of a piece of material to restrict the fuel flow. Have you ever noticed that the float bowls are empty of fuel?
Charley
 
Well I got it late last night. I put the original pump back on I started with, but some needles and seats in from some old carbs I bought on EBay that were made of solid brass, I think, (the old school stuff ) plus they were like new these old carb were in great shape dusty and sitting for years inside. of course That is after I ordered some of those Vinton seals that just arrived from Moss that I am not sure of and did not use.

Anyways it worked out good because I dug out all my fuel stuff. I liked John’s idea of the large fuel filter before the pump, but found an old glass one with the cleanable filter with my stuff and tried that, but again the larger capacity is smart. I was about ready to try David idea with a different tank on the ground. What real probably fixed it for now is years back Randall was helping someone and said blow air back through to move stuff around, and I did that, But the second time I blew it for probably 30 seconds to a minute at 125 psi and even popped the gas cap up. but vooom vooom.
Steve
 
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