rebuilt the dellorto a month ago. used the car up until last week when i used my gsxr for work. go to start it up and i got a bit of varnish leaking down the stacks already! and it doesnt idle until i put my hand on the stacks and gun it to clean the circuits.(gas is about two weeks old only and have only filled it up twice since i rebuilt the carb, used 87 chevron)

My boss rebuilt my carb for me(im not that experieced with dellortos) and showed me everything before it was re assembled so i KNOW it was clean.

Why is my gas turning to ****? if i use the car everyday shes fine but if she sits for more than 72 hours i have to do this procedure! Its very annoying! Any good safe additive to stop the varnishing. it shuldn't gum up that fast by only sitting a week rite? is this because its a sidedraft and sits ontop a hot motor? i dont know, its too late rite now n ive had a long day but any insight on this problem is greatly appreciated!!!
Thankyou!

 

In having the same problem. The research I've Found is its the nature of a fresh rebuild. Things have to wear and groove.

 

are you premixing?

 

not sure if i'm missing something, but he said his Dell'Orto was rebuilt, not his engine. i can't think of anything to "groove" in the carbie.

 

Yes forgot to mention, no MOP, i premix 1 ounce to 1 gallon of idemitsu!

 

i was thinking the same, i thought he ment the leaking varnish down the stack was normal. im not to worried about that even though it spills onmy polished housing but the fact that it idles funny if it sits for 3 days is what im not figuring out! not until i put my hand on the stacks and floor it.?

 

What I was talking about is the needles and everything micro groove. I'm basing off of a standard carb not a del ,shouldn't be much different?. Can you take a picture of where the leak is coming from for these guys? I know the whole point of a vent is so you let air out and when you close it, the gas won't evaporate.

 

I honestly have no idea how to get the picture from my phone to this computer but i will try, probably wait for my sister cuz she knows how to do all that. But anyways its basically just leaking down and out the stack (sidedraft, so it leaks onto the intermeadiate housing and the rear rotor housing). and instead of it being nice goodlookin gas it instead has the brown tinge in it. it is not that big a leak. in fact it reallt isnt noticable until the third day! then i just wipe it off but if i wait that long she gets the funny idle.

Oh yeah and if it makes a difference the small leak happens to both stacks!

 

Dells will spit back when they run depending on how rich the mix is and how hard you run it.
My air filter always has a bit of gas along the bottom of the filter but it doesn't flow down onto
the block at all.

If my Dell sits for awhile, I have to turn the key and wait 10 seconds just to make sure the
pressure is there and the bowls are topped up. Then I use the choke and start it up (in cool
weather at least).

Do you use the choke when you start it? Has the weather been a lot cooler now where you
live?

You may have a stuck seal and its not the carb at all. My car, if it sits more than a few days
basically starts fine but is running on less than 2 full rotors. One of the seals doesn't pop until
I rev it carefully past about 4K then it usually breaks free and is fine. This always happens
when its sits for more than 1 week. Always. I've got 120K on the motor.

 

ok then it is a bit normal, i took the filter off to see this happening and haven't put it back on but yes the filter does keep it from dripping on the housing, it just gets a lil soaked with that nasty brown color on it. i will throw it back on when i get home.

my dell has no choke on it. And its has gotten EXTREMELY COLD in this last week(enuf that my plants outside froze). And i live in california!! I keep the rpms at about 1500 for about 2-3 min then drop it to idle at 800 and thats when it sounds like its misfiring. also shakes quite a bit when it does this. Then i would put my hand over the stack and WOT to about 4K and it would idle fine after this. I guess i just figured it was gas related since the carb is rebuilt and it already has varnish in it.

I never thought of a stuck seal! Thankyou! i will let it sit for a few days then just revv it up without puttin my hand on the carb and see if it still works.

 

^only thing is, is that anything off idle sounds great tho, but i will try to de-carbon the engine and see what happends.

 

BTW, when it does this and I start and rev it up, it will leave a nice smoke screen for a few
seconds. Neighbors love it I'm sure.