ox66 vst filter problem - The Hull Truth

dadsdayoff2 · 05-14-2009, 10:56 AM

First 3 Trips Of Year No Problems. Next 3 Vst Filter Clogged On Way In.(cleaned Vst Between Trips) Main 10 Micron Racor Filter Only Had 50 Hrs On It. Put New Main Racor, Fuel Water/filter On Side Of Motor And Vst. Also Replaced 3 Lp Fuel Pumps (old Ones 3yrs Old/450 Hrs) And New Primer Ball Hose Assembly. Checked Long Oil Filter In Tank On Motor And Was Clean. Went For Short Ride 1/2 Hr Motor Ran Like New. Pulled Vst For Inspection And It Looked A Little Dirty. Question Is- Even If Fuel Tank Has A Little Crap In It, Should'nt The Racor And Motor Mounted Filter Catch It Befor It Gets To The Vst? Btw Opened Up Old Racor, Only Bottom 1" Of Filter Looked A Little Dirty, A Flour Like Substance No Real Grit Or Dirt. I Fear My Problem Is Not Over.thanks, Ken

FlyTuna · 05-14-2009, 11:02 AM

Supposedly the filter in the VST is a Micron 2 or 4, so even though your Racor traps the bigger crud, smaller deposits still make it though & get caught in the VST. I have heard of people going to a Micron 2 Racor. I have the same issues, but I get about 60 hours in between cleanings.

dadsdayoff2 · 05-14-2009, 12:02 PM

Thanks I have a call into my parts guy now. I wish he told me about the 2 micron before I just replaced the 10 micron.

mronzo · 05-14-2009, 02:47 PM

Don't bother cleaning a VST filter! For all the bother of taking it apart just put in a NEW
one! This is not an area to cheap out on!

Thomasy · 05-14-2009, 02:54 PM

If you are using gas with ethanol in it, the VST filter develops a glaze. Yamaha is getting rich off these suckers but no alternative but to go new.

hatterasman · 05-14-2009, 05:30 PM

yamaha also pumps the oil into that tank and there can be problems with different brands of oil also, the clearer the oil the better had zinc crud on mine once. zinc is a cheap additive in some oils for better lubricity

ghost28 · 05-14-2009, 06:11 PM

what oil are you using??? dirty and or poor quality oil is a killer.....also when you are cleaning the VST filter are you cleaning th rest of the tank and ALL components inside thouroughly???

How old is the pump in the VST?? they have been known to come apart slowly causing the filter to clog....

hope this helps....

49erJim · 05-14-2009, 09:28 PM

Are you running twins or a single engine? Do you have two tanks or one tank?

mronzo · 05-14-2009, 11:45 PM

Quote:

Originally Posted by Thomasy

If you are using gas with ethanol in it, the VST filter develops a glaze. Yamaha is getting rich off these suckers but no alternative but to go new.

Exactly what i was saying! If you take an old VST out and clean it, then hold it next to a
new one you will see how gummed up the old one still is!
Funny thing is I've read about it here on THT several times about folks cleaning the filter,
the engine running fine for a while then the same symptoms!
When my port engine did the same thing 2 yrs ago I diagnosed it as a VST correctly then changed the starboard as well!

dadsdayoff2 · 05-15-2009, 11:17 AM

Hey guys, thanks for all the help. I am running yamalube & ring free. The tank is clean everytime I open it. The deposits on the vst filter look like varnish. I only have one tank. 3 years ago I had the same problem, replaced the vst and that did it for 3 eight month seasons. The 3 trips in a row that it clogged was on a quicky cleaning of the old filter while waiting for new. I guess I will find out over the holiday weekend if all new filters did the trick. BTW 2 micron Raycor filter is in the mail.

John_Madison CT · 05-15-2009, 07:16 PM

I agree about cleaning a VST. It's so fine, i don't think you can do it good enough.

ghost28 · 05-15-2009, 08:43 PM

all i can say is that to properly clean a VST system the entire system MUST be removed from the motor and disassembled 100% then all parts carefully and thouroughly soaked and then cleaned with a high strength cleaner (i like spray nine)....once all parts are cleaned i rinse them one at a time with HOT water and dry them one at a time placing them on clean, dry paper plates....once all parts are clean and dry i carefully re assemble the VST checking the float levels and i dont have any issues with them...

i also blow out all the fuel systems lines and VST nooks and crannys with compressed air to make sure all of the water is gone....

if not done right you are just wasting your time doing it because it will clog up again in no tome.....

hatterasman · 05-15-2009, 08:55 PM

also be sure to get the updated filter with the larger screen area