Community Forums

RickGyver · 06-03-2012, 09:26 AM

My 1995 Dynasty primary fuel filter drips fuel as it is driven,,not at idle, sitting still. I test-wrapped paper towels around hose ends and then drove 350 miles. Towels were dry so it has to be the large rubber gasket on top of filter. I had a filter with the plastic bowl and switched to the no-bowl filter. Both leaked. It makes such a mess on the rear cap!!! Last week,I had to pull the boat thru the car wash before launching because there was such a mess on boat after 350 miles at about 60mph. I think there must be a specific way to install, eg; torquing? I'm going to try a new filter once more. Would too fine a filtration/micron cause back pressure? Ok Mike C,,,what's the solution?!!

THX!

deSanford · 06-03-2012, 03:04 PM

I would buy a NEW filter both primary and secondary complete assembly.........deSanford

Buford B · 06-03-2012, 04:20 PM

Carefully check to make sure that there is not an extra gasket or piece of one stuck to the mounting flange.

Robi.1014 · 06-03-2012, 06:52 PM

Mike C has such broad experience, I'm looking forward to his input as well.

But I'm interested in your "My 1995 Dynasty primary fuel filter drips fuel as it is driven,,not at idle, sitting still." The fuel pressure that is present at the primary filter is constant....whether at idle or being driven.

Your shifting from a filter with a plastic bowl to a filter with no bowl combined with your great idea to test (with paper towels) the entering and exiting hoses represents great forensics. What has me scratching my head is how can it be that a "no leak" condition at idle can turn into a gusher leak when driving .... where the leak is so bad that that it coats your rear cap and any other vehicle in close proximity. Might there be another leak source?...or have you confirmed that all is good excepting the primary filter?

docj · 06-03-2012, 07:12 PM

Not knowing how your system is configured, I can only offer my own recent experience in which I had a leak from a plastic prefilter ahead of my primary. My coach is configured with a Racor prefilter and primary and a CAT secondary filter. My leak was less than you are reporting but was increasing steadily. Fortunately, the leak was resolved by replacing the prefilter.

You shouldn't be concerned about "torquing" your filters. They hand tighten the same way oil filters are installed. If you get them too tight I think you'll distort the seals which may make the leak problem worse.

Barlow46 · 06-03-2012, 08:31 PM

Quote:

Originally Posted by Buford B

Carefully check to make sure that there is not an extra gasket or piece of one stuck to the mounting flange.

x's 2 on that extra gasket stuck.

RickGyver · 06-04-2012, 08:39 AM

I'm going to change both filters today and see what happens. The present ones only have a couple thousand miles ea.. I have had the aluminum block that the filter screws to apart with new "O" rings. I also have removed primary filter gasket,cleaned, lightly greased and reinstalled. Still leaks! Sure glad cussing isn't acceptable here! GRRRRRR!

Twomed · 06-04-2012, 09:13 AM

Picture would help. I am sure some of us are thinking you may have the older style Winn unit which is know for leaks,and many have replaced.

What part # and brand of filter are you using??

vito.a · 06-04-2012, 10:31 AM

I had a similar issue on a 97 Dynasty. It turned out it was one of the injector hard lines that was leaking at highway speeds, not the filter. Still, it was tough to isolate because fuel would go everywhere, but only at highway speed, not at idle.
It would also cover the back of the coach and anything towed behind it.

RickGyver · 06-07-2012, 06:09 PM

Just installed a new fuel filter. My coach has only one filter.(95Dynasty) Fram isn't the best filter but tried one anyway. Tightening directions puts filter case right up against the mounting plate. The filter came with an o-ring which I installed on the thread post. Will let you know how it works! When filling filter with fuel,,,,use a 3/4" PLASTIC pipe nipple to plug center hole,,,not the same thread pitch but works OK. Finger tight only!

RickGyver · 07-05-2012, 02:43 PM

Filter still leaks after July 4th trip. Could it be the return line or primary fuel pump? thx

Old Trucker · 07-05-2012, 03:15 PM

Quote:

Originally Posted by RickGyver

Filter still leaks after July 4th trip. Could it be the return line or primary fuel pump? thx

Hi Rick, sounds like you have tried very hard to do your home work. When I read your first post I was thinking that the O rings that goes around the threaded stud could be gone or there could be one left behing from the last change, end result 2 rings??? You rebuilt the mounting plate,,, how about gasket betweem filter mount and the block?? I doubt very seriously that the actual filter is your problem. Someone mentioned the hard line to an injector?? I think you have something leaking elsewhere and fuel is running down in the area of your filter, causing an illusion. I have had a steel injector light loosen, I have also have had them vibrate and crack, or rub against something else and wear a hold in a line. I am a retired cross country trucker. I put 3,145,000 miles on the SAME TRUCK. You mentioned possibly to much fuel pressure. My truck had a fuel pressure gage, pressure increases with the demand of fuel.. Wish I ccould be more help. old trucker

Old Trucker · 07-05-2012, 03:33 PM

Quote:

Originally Posted by RickGyver

Filter still leaks after July 4th trip. Could it be the return line or primary fuel pump? thx

Hello again Rick, I just went back and re read your original thread. I must be missing something. You say no leak around the filter or fittings, no drip in the driveway...Why continue to fight filter problems??? Sounds like you have really tried to do your home work. There is a song called ""looking for love in all the wrong places""I wonder if you are not looking for fuel leaks in all the wrong places.???? You apparently have a high pressure leak since it blows fuel going down the road but not at an idle.. Fuel pressure increases with demand. At last resort, take it to a truck shop, put it on a dyno, with the bed raised, I would think someone could see a light spray of fuel.. Second thought. Get someone to ride with you, someone drive, someone be looking at the engine from under the bed.. just a thought. It is always easier to try to tell someone else how to solve their problems. best wishes, old trucker.

Dutch Star Don · 07-05-2012, 07:56 PM

Rick....I'm going to ask this question just to double check. On the newer filters, not sure about yours, there is an o-ring on the inner thread. Did you make sure that you only have one there now. Could an old one still be on the thread and you have double o-rings installed.

Just as a side note, I wipe my thumb to make sure it is clean and I place it in the center hole while filling the filter(s). Works well and seals tight.