fuel filter vapor lock?

[CMA_Carl]

1999 standard, 150000. miles, interstate computer, darkside. Just a couple thousand miles ago i changed out the oem fuel petcock for a pingel with no vacuum. added a mr gasket fuel filter and a Dan-Marc fuel shutoff.
Three times last week it almost laid down on me. All three days were over 100 degrees here in Kansas. I could tell the bike was hot... not so hot that the hot indicator light would come... just hot. Well, going along the bike acted like it was out of fuel! I switched to res, but it didn't help. One time i was out in the flint hills and could not pull over... drop mph down to about 55 mph with only a few cylinders running and rode that way for a couple miles all the while fooling around with the petcock from run to res. Finally it hit and one by one the cylinders started getting fuel and started running. I left it in run and finished the ride at 75mph. On the return trip she didn't miss a beat... it was cooler by then. What's going on?

[R J]

Get rid of the firkin fuel filter, everyone who has added a fuel filter has had problems that I know of.        I took mine off and threw it as far as I could.

Was only like 5' as the garage door was down.     When I opened the door to go in the house, it got tossed in the garbage can.      That was I don't know how many miles ago, but it hasn't faltered since.     

[bikerboy1951]

If you want to run a filter, try Golan.  It is rated at 10 microns and has a fuel delivery of 5 gallons per minute.  I have had one on my standard for three years and no problems or issues whatsoever.

Brad

[Thunderbolt]

If the fuel line is just a very small amount too long and the temperature gets hot enough it will kink and cause the problem that you describe.  I have never experienced that, but did read it on this very tech board.  I put in the Pingle also, but no Dan Marc and no extra fuel filter.

[olddog1946]

MMM, I must be a lucky old fart.  I've got one of those plastic fuel filters that I put on my lady the first week I had it and run over 25000 miles since, in temps well over a 100 and have never had a lick of problems.  I also had a red eye quick disconnect, but removed it due to the seals spliting every time I took the lines apart.
I does indeed sound quite similar to a vapor lock condition and my first guess would also be the filter.  Change it out or remove it and see how she goes. If the symptons re-appear, look elsewhere.

[Patrick]

I've use an in-line filter for as long as I can remember without any issues. I haven't ridden in that kind of heat though.

[RDROGUE #0128]

I realize this is an old thread but never saw a post with discovery of problem.

So I'm adding my 2 cents from experiencing same symptoms after not reinstalling the plastic heat deflector behind radiator after pulling carb banks.

May help someone else considering not re-installing this necessary component.
 

[JC]

I tried twice to modify the fuel line and both times had the same problems you describe. I installed the 'quick disconnect' and she wanted to vapor lock on long rides with a temp above 85° or so once the fuel level dropped between 1/2 to 1/4 tank. Removed the disconnect and extra line, problem solved. Then I installed a Dan-Marc and had essentially the same problem, and resolution again. I was always careful with the length of the lines to avoid kinking, and never had a problem when the tank was full. These are just my experiences, and your results may vary, but I went back to a stock setup and all is good.

[R J]

That is a weird problem.

I've ran a Dan Marc switch and a Pingel petcock for close to 3 years now and NO problems to date.

I've also run MGM like he had just been shot in the butt with a cow prod.

Still runs good and when I hit the go button, it fires and idles like a sweet oiled clock.

You are doing something wrong with the Dan Marc.

I'll agree with problems with the quick disconnect.

I put one on and it was a pain in the arse from day one.

It lasted 6 months before I took it off and tossed it in the garbage can for pickup.

Peace.

[John Schmidt]

Well, guess I'm either blessed or did a good job installing my setup....or both.    About six years ago I installed a Pingle manual petcock, an inline filter, and the DanMarc. The one thing I did that many others didn't do....I made certain everything was running downhill from the petcock all the way to the T. I've done some repairs on other bikes with the trouble mentioned above, and in every case there was enough extra fuel line to create a low spot in the delivery following the filter. You can't have that or it will do exactly as described, that is...it will begin to starve the engine when low on fuel. It appears to be due to less weight pressing down on the fuel delivery since it's gravity feed and can't push past the low spot, because soon as the tank is filled it runs fine. I have not had the first minutes trouble with my installation and I'm no more talented than anyone else. Blessed, I'm sure....since I'm still here.