Help Needed - Fuel or Electrical

[Jim_Gruber]

I just had this for the 2nd time in 2 days with Bugsy. 68 Sprite with 1098. Driving along, engine is running really sweet, sound absolutely fine and is pulling strong. All of a sudden power starts to drop off, at least 1 cylinder drops out and then the engine sloly starts missing worse and then just dies. I pull over to the side of the road, turn the key, hear fuel pump tick, and engine fires up and I can drive on without a miss.

Now the only thing done to the engine recently was taking off the stock air filter cans and I am running with just filter base, filters on, with a cap plate on top of the filters to secure them in place. I would think that more airflow would tend to lean out the engine and I would need to adjust mixture but not to the extent that engine just completly dies.
But then starts up again after it craps out.

I'm thinking either fuel filter is clogged and needs changing. I can't recall ever changing fuel filter in 9 years or electric fuel pump is starting to crap out. I'm thinking Faucet or something similiar is back under the PS rear fender area.

Thoughts or ideas. Got the back yard to cut and I'm hoping this list has some ideas for me when I return in about 45 minutes. 75 degrees and sunny, I want to go cruising but now worried about straying far from home. Help!!!!

 

[Jim_Gruber]

Also anyone got a favorite replacement if it is the fuel pump?

 

[RickB]

I like the Facet, not the cheapo $30 unitbut the one that's about $70 and is about 2" diameter & 5 " long.
It's loud but it delivers.

 

[Jim_Gruber]

OK possible answer is vent on gas cap from Frank C, . May not have been securely on all of the way. Did a test drive and all was fine, car running like a raped ape right now. All plugs are nice and tan, regapped to .025. Points replaced less than 1,000 miles ago I did not look at them yet.

Bill L suggests wiring back at pump or bad ground back there.

 

[regularman]

The back up pump is never a bad idea. These things are the worst sort. If you have points, have a look at the point gap. That gap can close up sometimes and cause similar problems. I still have not exercised all my demons, but they seem to go away in cool weather.

 

[Jim_Gruber]

Kim,

I drove it last night for about 10 miles after I tightened the gas cap and no issues. Remains to be seen whether or not that was really the issue of not. Rain, rain, rain coming today and next three days. Bugsy still does not have new top installed yet so probably Wed before he is back out and about.

 

[jlaird]

Kim, goes away in cool weather, what does that tell you. Hmmm.

Fuel line too close to exhaust?

Condencer?

Coil?

 

[regularman]

I don't know Jack. Its been so long I have pretty much forgotten all the little problems. The running hot problem still comes around after about 50-70 miles of driving. I still wonder if I have the right water pump.

 

[ncbugeye]

Another idea with more "authenticity" might be to have the fuel pump restored by Dave Dubois. I had a similar problem (the wife happend to be in the car with me, bad move) so I installed a facet for a while, and I so much hated the noise it made, I gladly sent off my pump to Dave. He replaces the "sparky" parts that usually fail in the SU diapragm pump with a fully electronic contactless setup, the result looks exactly like the original, ie like a brand new SU pump, but retains the dignified ticking that so many of us are accustomed to.

 

[Jim_Gruber]

Problem happened again this afternoon:

Temps mid 60's, started Bugsy up and drove 2+ miles down to the bank. As I go to pull in driveway engine starts running rough and within several seconds decides to completely crap out and quit. I rolled into the parking lots and stopped and immediately got out to check if tank was suffering from vacumn issues. No telltale whoosh when gas cap was loosened. Ok there goes that theory.

I came out from bank and restarted Bugsy. Fired right up, sounds great, and I go maybe a mile down the road on another errand. Coming up to a stop light I notice the engine starting to misfire again like it's running out of gas. I pulled the choke out and pushed in immediately back in and sputtering went away.

A fellow lister wrote to me speculating about possible carb icing issues that might be happening. The fact that problem corrected itself immediately when I pulled on the choke leads me to believe there is some possibility of this happening.And carb icing would be disapated and correct itself automatically just from internal engine heat. Filter bases are on properly with extra hole lined up properly.

Only change to Bugsy lately has been changing from standard filter setup to a stock filter base only with a filter and plate to hole the filter on with stock bolts. Issue seems to go away once car is fully warmed up and I can leave choke all of the way off. This setup allows substantially more airflow to the carbs and I would assume leans out the mixture a lot. I have not tried tuning the carbs yet as Bugsy seems to be running real well other than when he decides to simply die on me.

Anyone run into this before. Other than changing the filter setup and fixing throttle linkage, broken cable, nothing has been done to the engine.

 

[spritenut]

I think you have a float out of adjustment or maybe the float sunk.
Ladybug just had the same problem. Driving around and all was fine, turned the corner at home and just made it into the garage when it died and the smell of gas was in the air.
One of the floats was full of gas and it sunk. But it took 2-3 weeks before it sunk enough to cause a problem. But too much fuel in the float will cause rough running. Also check to make sure your choke is fully up, not so much the cable but the jets themselves, they could be stuck down when you pulled the choke.
And a sticking piston on the carb will cause problems too. It goes up, gets stuck causes the problem but if falls back down a second or so after it stalls.
Clean out the inside of the dashpot where the piston rides, wipe both parts out with a clean lint free paper towel and check the movement

 

[Jim_Gruber]

Thanks Frank,

Looks like some Saturday morning diagnosis needed with the carbs.

 

[Jim_Gruber]

Thanks everyone for the response to my querry re. Bugsy stalling out and dying on me. After reading all of the opinions here's my plan of attack.



1) Recheck fuel pump electrical connections. I redid them 8-9 years ago and they appear to be crimped connections. I will pull apart, solder correctly, use heat shrink and make sure fuel pump is getting proper power source.



2) I have pulled the tops off of the carbs and bowls were clean, not a bit of crud in there and I have seen some occasional stuff in there but seldom



3) Put old filters back on and see if problem goes away.



4) Check dashpots and piston action. All seemed to be moving freely when I checked and looked at it last week.



5) I did fill dashpots up last week as they looked a little bit low with 3 in 1 oil. I've used in the past and have not seen any issues with it in the past.



6) A dose of carb cleaner probably won't hurt to spray in there.



7) low to mid 80's today in Dayton. I need ot get out and drive.



Thanks again.

 

[radibob]

Same problem here, thought it was the gas cap too , it was the fuel pump.
I would replace all fuel line when you do the pump in case some of it is collapsed or blocked and look for rust from the gas tank because that could be the ultimate culprit here.

Bob B.

67 Sprite
73 Alfa GTV
99 C 5
06 Mazda6 sport wagon
Other junk I don't want to mention

 

[Jim_Gruber]

Bob,

Issue was +12VDC Lead Vibrating loose on the coil. Nut was just barely finger tight and connections were all cruddy, greasy, etc. Once cleaned up and tightened down, vroom, vroom noises once again. Bugsy is very happy.

 

[jlaird]

Well done Jim. Fun isn't it?

 

[Jim_Gruber]

Jack,

Bugsy is always fun :banana: It's the problem solving practice that you need to do on a regular basis that makes these cars so interesting. Same thing with my other hobby racing small sailboats that I recently gave up due to lack of time. A constant problem solving exercise to make the boat always go faster, but with the additional challenge of getting it around the bouys by going the correct direction, by figuring what the invisible force namely the wind is going to do next. A mental challenge that one either gets or doesn't get. My better half wants to be on the water skiing behind our SeaRay. She has never understood racing small sailboats period. It's the same way with these little cars, you either get it or you don't.