TheSamba.com :: View topic - best way to keep weber idle jets from clogging?

Thu Nov 12, 2009 2:42 pm

I am so sick of my rail not idleing. I have dual 44's with K&Ns and Sand Socks (Outerwear) over them but sand still finds a way in there. Any suggestions on what works better.

Thu Nov 12, 2009 3:08 pm

Maybe go with a UMP filter set up?

Thu Nov 12, 2009 3:35 pm

will that keep out the sand?

Thu Nov 12, 2009 3:39 pm

Seems to work on race vehicles but it's kinda big.

CB also sells something called a "jet doctor". Supposed to help keep the idle jets cleaner I think.

Thu Nov 12, 2009 4:43 pm

Try using some grease on the top and bottom of the filters before you put them back on.Also make sure fuel tank is clean and a decent filter on there.

You are oiling the filters too right?

I have been runing the empi hpmxs for 2 full seasons and have only had the jets plug twice once was when new the other after i pulled the heads off to have ported must have a grain of sand that fell through.

Thu Nov 12, 2009 4:56 pm

What size idle jets are you using? Anything under size 55 clogs up too easily in the offroad environment.

Thu Nov 12, 2009 8:26 pm

Chuck the Webbers and buy some Dellorto's

Thu Nov 12, 2009 9:21 pm

What type of filter base do you have? If you have the stamped steel ones that’s the problem. I had them on mine and when you tighten the nut to hold the top it pulls the bottom away from the carb allowing dirt in. The jet doctors do help but all they to is raise the vent on the jet higher so it won’t suck in dirt as easy, but that dirt will still get into your motor. I put a Donaldson industrial air cleaner on mine and haven’t had to clean a jet since. The Donaldson is a cyclonic air filter just like the UMP style, and costs half the price if you find them on ebay or similar.

This is the best and cheapest air cleaner I have used in 12 years of riding.
The most expensive part was the filter. I got 2 of them from craigslist for $35 each and about $20 in pvc. It's not as nice as the UMP but woks great so far. I found the filters listed as industrial air filter.

Here is the entire build up thread of my filter.
http://www.woodsbuggy.com/index.php?option=com_jfu...industrial

Thu Nov 12, 2009 9:58 pm

HILLAHOLIC wrote: What type of filter base do you have? If you have the stamped steel ones that’s the problem. I had them on mine and when you tighten the nut to hold the top it pulls the bottom away from the carb allowing dirt in.

I use the stamped steel ones myself and no probelms.i also used permatex aviation on the gaskets for the bases.The grease really helps catch any sand that trys to go past the filters near the base and tops.

I like your filter set up too some day i plan oon doing a canister type.

Fri Nov 13, 2009 12:29 am

shamill wrote: will that keep out the sand?

CB/ UNI foam type filters over K&N'S with Outerwears over em' works for me in the sand. Probably gives up a little performance due to restriction but it always idles.

Fri Nov 13, 2009 12:24 pm

Your main problem is your filters. K&N's have no place on a off-road vehicle. UMP's are the best filtering unit out there, they just don't flow all that well. I would recommend running 2 of them. That might be a little spendy for most people, if you have a tractor supply place near you you can get a Donaldson plastic housing filter that looks almost the same as a UMP and takes the same filter cartridge for about half the cost........

Sun Nov 15, 2009 6:36 pm

Use better fuel filters. Many Weber idle jet issues are caused by particulate in the fuel system.

Mon Nov 16, 2009 9:28 pm

I have done the following and it works well for me:
Cast filter bodies (looks like you have them).
Outerwears that fit and K&Ns that are not all worn out.
Extended main jet stacks. These are extensions that fit on the air correction jets.
Pieces of air cleaner foam cut and fit around the main jet stacks to prevent sand from getting down into the float bowl.
You should clean your filters and Outerwears after every trip.
Velocity stacks do not help with the plugged idle jet problem but they do help keep "stuff" from getting down into the cylinders as easily.

Basically, sand gets into the idle jets via the float bowl. Keep that clean and protected and you should seldom have any problems. You may have to go through the carbs and clean the innards out to get a fresh start at this.

By the way, Dellorto carbs have not been available new during this century and they are miserable in off-road usages because you have to take the air cleaners off to get to the idle jet screws.

Mon Nov 16, 2009 10:25 pm

personaly for off road I dont like the dellorto style cast cleaner base . because the way the linkage hooks up does'nt allow for pre filters to go all the way past the bottom of the filter.

sand & dirt will collect there and work its way into the carb.

I agree with lostinbaja dirty fuel system would be my first guess.