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need troubleshooting help with 100-6 fuel?electrical?

hubosity

Freshman Member
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First of all, I feel self conscious wading into the rarefied water of those of you who treat their healeys with more respect. My 58 BN6 has been in my garage for 30+ years, and has not had any work done since the half a$$ restoration I did when I bought her in college. Now we only get out maybe once or twice/year. Despite the neglect, though, she has always been reliable(and fun).

Today was an exception. She started easily, purred at idle, revved freely and sounded ready to go. Once on the road, it accelerated nicely through first and second gear, but about mid-way through the range on third gear....sputter sputter...cough cough... slow to a crawl...trying desperately to keep the engine running while I look for a place to turn around. I was able to limp back to the house. Once there, the idle smoothed out again and sounded fine again.

After a brief inspection under the hood, I noticed one problem that may or may not have been related. The wire running down to firewall that carries power to the fuel pump showed a bit of exposed copper and the insulation crumbled on touch. Checking under the car, I found the same condition for the length of the wire, so I ran a new length of wire all the way from the fuse block to the fuel pump. My thinking was that maybe the wire had been damaged under the car and had started to short to the frame leading to high current/high temp/melting wire. However, my next attempt to enjoy Sunday afternoon had the exact same result. (Ran fine at idle, revved freely without a load, drove through 1st and 2nd but half way through 3rd started sputtering, backfiring (exhaust and in the carbs), stalled, but once limped back to the house the idle returned back to normal)

I am now thinking that the fuel pump itself may be the culprit for the cooked wire. It is not the original SU. It is a small cube shaped electric pump obtained from an auto parts store back in 1984. It sounds like it is running correctly and the wire is not noticeably hot, but .....

This is the limit of my troubleshooting ability for today. I was hoping someone more in-touch with their inner "beast" could save me some time by pointing me in the right direction. It would be much appreciated

Rich
 
check the coil...my experience has been that if bad they will cause the symptoms you describe i.e.: fine when cold, flaky when hot.
 
Check the fuel tank for rust. Back in the 80s, when my Healey was a daily driver, I had a similar problem, except it would "run out of gas" completely, and stall. A minute later, it would start and run fine__until the next time...

... it was picking up layers of rust, the suction holding it to the bottom of the pickup tube, until the suction was broken (when I'd kill the power via the key). I don't remember if new tanks were even available back then, and even if they were, I probably couldn't afford one, so I rigged the fuel line with a quick-disconnect coupling and carried a mating half with about three (3) feet of hose attached. When the car stalled thereafter, all I had to do was blow back through the hose and clear the debris, without ever getting out of the car (also a BN6 with the battery hatch door).
 
Thanks for the helpful suggestions!

I ordered a new fuel pump and filter
I'll check the floats too
when I swap the pump, I'll drain the tank to see how much "crap" comes out. It is an original tank with no effort to add a coating, etc.
If these fail, I guess it's time to check electrical, starting with the coil (which is also original - meaning older than I am)

Randy, I love the image of giving my fuel tank CPR! Maybe I could install the "burp" hose with a tee and a shutoff to further optimize the process!
 
My vote is for the fuel filter. At idle there is not much demand for gas so a trickle will do the job. When accelerating you run all the fuel out of the carbs and the filter restricts the replenishment. I have had several of those cube pumps and have only had one go bellly up.
 
Thanks for the helpful suggestions!

I ordered a new fuel pump and filter
I'll check the floats too
when I swap the pump, I'll drain the tank to see how much "crap" comes out. It is an original tank with no effort to add a coating, etc.
If these fail, I guess it's time to check electrical, starting with the coil (which is also original - meaning older than I am)

Randy, I love the image of giving my fuel tank CPR! Maybe I could install the "burp" hose with a tee and a shutoff to further optimize the process!
I had junk around my pickup in the tank and disconnected the fuel line from the pump to the tank and blew it out. Took care of problem for many years until the line got clogged. I recommend removing the Tank and having a Radiator shop clean it out, check for leaks, new paint and reinstall. Then, disconnect all fuel lines and blow each one out with an airhose. You won't believe what comes out if its never been done before.
 
Your pump are probably a FACET a very reliable little pump it need a filter before it- better if LARGE dim.as suggested by Randy and Patrick also the tank must be cleaned and
I can add a cleaning also the pipe from the pump to the carburators easy to do disconnecting the terminals and passing inside a long hard electric wire or better the Nylon probe that electrician use for wire installation
https://picasaweb.google.com/lh/photo/zaHFZ1VagimaPxGP_bntkdMTjNZETYmyPJy0liipFm0?feat=directlink
 
Just pull the fuel hose from the carbs, stick the open end in a receptacle and turn on the pump. If it trickles out, it must be fuel related like the tank of pump filter.
 
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