possible intake leaks

dstar · Post by **dstar** » Tue Nov 23, 2004 8:03 am

platform115 wrote:Oh yeah, and I wasn't serious about wacking the carb.. hehe

I WAS!

Don

platform115 · Post by **platform115** » Tue Nov 23, 2004 9:16 am

so is there any good reason why the same setup would have worked fine before???

until my idle started creeping up, and my carb started not corresponding with its respective adjustments everything worked fine.

I've gone through the weber book time after time, and can't figure out what could possibly cause this...

raygreenwood · Post by **raygreenwood** » Tue Nov 23, 2004 10:42 am

An explaination as to why the carb ran before and not now? (1) is this a different engine?(2) is this the same fuel plumbingsystem ...meaning pipes hoses , filter...in the same tank volume in the same vehicle?

Regardless if a pair of diferent engines are the same size and comprise the same part #'s in their assembly...they will always run differently. Too many variables, balance, compression, valve speces, cam, intake manifold casting variances and most especially exhaust.... a jillion little things, can cause one engine to have more or better flow than another engine...or worse flow. This changes how the carb meters. Dstar is correct. On ALL engines regardless of wether its injection or carbs, the two FIRST and FORMOST adjustments are fuel pressure and fuel volume. They are also totally different things but interrelated. If you don't get those right first...or at least to a known constant....everything else is just screwing around.
Also, if you take an electric pump from one vehicle...with say 7mm fuel lines and thesock filter still in the tank....and put it on another vehicle with say...7mm lines and no sock filter, the pump (especially low volume electrics like carb pumps) will pump totally different volumes and pressures. Add to this.....how is the voltage supply stability of where the pump draws power from....different or the same in each vehicle? Thats a huge difference. My advice...personally...is to dump the center mounted progressive. Either that...or make a nice doorstop with it. Ray

platform115 · Post by **platform115** » Tue Nov 23, 2004 10:56 am

I see. That makes good sense.
I can't dump it, because I'm poor.

BUT... I will get a nice set of duals in a few months when I've done enough dancin' for the man.

raygreenwood · Post by **raygreenwood** » Tue Nov 23, 2004 4:31 pm

Ah...I understand the poorness coefficient......just be sure to apologize to the car for the temporary insanity

Ray

Post by **Piledriver** » Tue Nov 23, 2004 4:50 pm

They don't even make good doorstops, tried that, too many pokey things sticking out ;-)

platform115 · Post by **platform115** » Tue Nov 23, 2004 5:00 pm

It would be a funny thing to make a water sprinkler out of

dstar · Post by **dstar** » Wed Nov 24, 2004 7:33 am

Your carb is done. Unfortunately I won't be able to get to the post
before they close for the holiday!

Well, I guess it gets there when it gets there.

The carb ran smooth as silk on my engine, but again, will require
very SLIGHT adjustments when you get it.

My fuel pressure was set at 3PSI on my regulator(Yea, the CHEEP one!),
which shows 2.5 on my elec gauge.

Hang in there, you should get it by Monday.

Folks, these carbs WILL work, it just takes a LOT of work and tuning
to MAKE them work!

Heck, I have pipe insulation on my runners to keep them warm in the
winter and it looks like sh_t, but the carb works GREAT, even in the
mountains during the dead of winter!

Don

platform115 · Post by **platform115** » Wed Nov 24, 2004 9:48 am

you're the MAN!
that's awesome.
I can't wait to get that thing on my engine. I'm going to put some insulation around my intake as well, it just makes sense.

The carb ran smooth as silk on my engine, but again, will require
very SLIGHT adjustments when you get it.

That is great man. What rpm did you idle at?

Folks, these carbs WILL work, it just takes a LOT of work and tuning
to MAKE them work!

Hopefully you have time to give me a run down of what all it took sometime.

Thanks a lot man! My poor bus sputters and chokes everywhere it goes.. but nobody thinks that's weird for an old "hippy van" anyway

dstar · Post by **dstar** » Wed Nov 24, 2004 11:14 am

I set the idle at 800 on a manual tranny and 750 in D on an auto stick.

It just took CLEANING! BUWAHAHAHAHAHAHAHAHAHAAHHA!
Man that was the nastiest crab I have ever came across!

I also shimmed the power valve so it wouldn't come in till higher RPMS.
You have to jet and tune a single so FAT, that when the PV comes in, it usually bogs the engine if it comes in at too low an RPM.

You will still need to set idle on it when you install it. Set your fuel
pressure at 2.5 - 3PSI also....do NOT bother installing the carb until you can verify your fuel pressure. You will only run BAD, then mess up the tuning trying to correct for wrong fuel pressure.

The elect choke is already set, if you HAVE to adjust it,
look at the marks on the TOP of it and move it ONE notch only!

It is already one notch RICH.....so unless you get some REALLY cold weather up there, it should be OK.

Don

platform115 · Post by **platform115** » Wed Nov 24, 2004 12:53 pm

I set the idle at 800 ...

wow... I can't even imagine a smooth idle at 800rpm...

It just took CLEANING! BUWAHAHAHAHAHAHAHAHAHAAHHA!
Man that was the nastiest crab I have ever came across!

Man... you shoulda seen the engine this puppy came off of!!
I thought the jets had to me modified too?

You will still need to set idle on it when you install it. Set your fuel
pressure at 2.5 - 3PSI also....

Yes, I've got the gauge, so that shouldn't be a problem.

What do you think would cause a carb to only idle at above 1100-1200rpm, and sound like it was missing or had a vac leak at anything below??
Or not respond to the adjustment screws properly...
I tell ya, I've checked this carb book completely, and I can't figure out what would go wrong that would make it this much of a pain in the ass....

dstar · Post by **dstar** » Mon Nov 29, 2004 6:51 am

I need your address to send this back to you......The addy on the box
was a mailboxes plus type addy.

Yes, the jets were 132 and 135, now they are 140 and 145....

I also installed a new power valve and new air filter(didn't come
in the mail till Saturday....

)

Are you SURE you have a weber on that?
The carb you sent me was a Holley progressive, not Weber!

Holleys run at 5PSI and Webers run at 2.5-3PSI.

I could tuned it at 3PSI, so lets try it at 3, then go up to 5
if you need to on YOUR engine.

Do you have the Superperformance book on Dellortos, by CB's
Bob Tomlinson?

THAT book teaches you about carbeuration in general and is better
than the tech manuals for understanding the THEORY behind carbs.

Don

raygreenwood · Post by **raygreenwood** » Mon Nov 29, 2004 11:26 am

But we already KNOW the theory behind carbs...don't we? Carbs were invented as a stop gap....so's we could drive while the engineers were designing fuel injection so we could drive BETTER!
The original carburetter was derived from an oil burning lamp found in mining towns (still looks and works that way...but we have a jet now, instead of a wick). The "carb" was based on the carbide lamps found on coal miners heads...thats where the "carb" part came from. When the first crude injection systems started coming out....most people in Germany, embarrassed that they ever fell for using the demon devices, began using the now even more useless carbs for paper weights to hold down their letters before the mail man arrived on his horse. Add "carb"...to "letters"...and a little linguistic bastardization...and you get carburettor. I think its a French thing actually. That theory goes ...that the French...after forgetting to load the statue of liberty with explosives before they gave it to us....figured that by secretly infusing our aircraft and auto industry with carbed vehicles....they would be able to whip our asses in the next war. They didn't count on it being on their own soil again.....sad really.....such a nice statue. All of these facts can be found in my new book...."From cro-magnon carbs to the master race of injection" ....carry on!

Ray

dstar · Post by **dstar** » Mon Nov 29, 2004 12:16 pm

raygreenwood wrote:But we already KNOW the theory behind carbs...don't we? Carbs were invented as a stop gap....so's we could drive while the engineers were designing fuel injection so we could drive BETTER! ....carry on! Ray

BUWAHAHAHAHAHAHAHAHAHAHAHAHA!

Carb bashing at it's FINEST Ray!

Don

platform115 · Post by **platform115** » Mon Nov 29, 2004 1:51 pm

Dstar, my address has been sent via PM.
I will check on getting that book.

Yeah the one on my bus now is a weber, well, at least it says "Weber" on it! so hopefully!
hehe