[99 to Life]

Ok, I know these are on here alot. I like to try and read and physically solve my problems, but I figured I would through this out there. Last weekend, I tore my carb apart. it is elec choke and was slightly used when I got it, thing is pretty clean on the outside so I know it wasn't run long. I had some sediment caught in my seat filters and in the bowls. So I replaced those and some gaskets. checked my floats etc. Put it back on with a .5" phenolic spacer to help with boiling gas. It helped in deed and was running good. Although my air/fuel gauge has read about 13 instead of 14 at cruise and idle, WOT reads about 13.5-14 I think.

Anyway I got on it a little while taking some friends out and all was fine, then as I made a turn, I noticed it bog (which it never has done) now my air fuel gauge is completely out. The biggest thing I notice is an obvious difference in sound and performance and when I close the choke at idle the engine revs up instead of bogs. So I am lead to believe I have a vacuum leak.

I have a vacuum gauge and I have reset the timing to 34 deg total, but Im running more like 15-16" of vac instead of about 18 I was running previously.

I still have to spray some carb cleaner around the base and try and locate leak, but is there anything that rings a bell? could a blown accelerator pump cause this? the throttle response is still ok and I have always had good response. but when idling and I rev it I can hear a whooshing sound more than normal. I definitely want to play with the jets and that later on to see if I can't get a better mixture, but for now, something is def up. I tried tightening down the carb again and it seemed tight. My secondary blades seem fine. If it was a sticky valve wouldn't I notice a sporatic vaccum?

any help would be appreciated, again I might find my problem when I tear back into it, but I'm trying to gather some ideas prior as well. thanks

[cletusvandamme]

what manifold you running- spread bore or square bore?

[99 to Life]

its the eddy 2101 square/spread bore manifold. I am running all carb no egr stuff. I tore carb off again, made sure everything was still good, replaced the acc pump rubber. I tried spraying all the bases I could with carb cleaner while running. Is that maybe not volatile enough to get a good rev? I did notice on the two intake bolts the carb cleaner would bubble and then evaporate, so maybe I have an intake problem. Everything was fine at one point, but maybe I need to retorque the intake. I am also going to try taking the spacer off and see if that is my problem as far as not seating properly. I really wish that is not the problem, because it has really helped with my hot starting. I checked all my vacuum lines and that doesn't seem to be the problem.

How i have it now, when it warms up, I'm running about 16" of vacuum, when I close off the choke a little it runs to 20" of vacuum. The leak is enough to make all my air/fuel lights go out as it warms up.

[75gmck25]

It definitely sounds like a vacuum leak. I had similar symptoms when the trans modulator line came off under my truck where it connects to the transmission.

Since the spacer is a recent addition, I'd remove it and try tightening everything up again.

Bruce

[cletusvandamme]

ok, here is your intake



you notice how the intake widens up in the back? you may have a the wrong spacer on that intake. I have a similar intake, in fact it looks exactly the same: my intake weiand 8004:


I recently took off my SPREAD bore open spacer and replaced with a SQUARE bore 4 hole spacer. I had massive vacuum leak since it did not seal the sides where the secondaries are here:



It was leaking from one or maybe both sides of the intake. You might have a smaller diameter square bore spacer on there not sealing the sides of the wider spread bore. That was my problem; loud whistle and hushing sound and not running right. I fixed with this adapter/block off plate here:

http://www.summitracing.com/parts/WND-9006/

"These 1/16 in. thick carburetor sealing plates from Weiand allow a square bore carb to mount directly to a spread bore aftermarket manifold and seal properly."

or you could try mounting the carb on intake with no spacer. Thats my best guess, that 600 edelbrock maybe wide enough to seal it.

I also have same 1406 600 cfm carb too.

[99 to Life]

yah that is my eddy intake. I noticed the spacer didn't contour to that opening too well. meaning there was gasket covering those corner pockets. But it seemed to have run fine on a 50 mile trip, then it just went. I'm def gonna try to run it without the spacer and see what I come up with. It definitely helped with my hot starting problem. Here is a pic of what I got.

[JeffB]

Go to www.summitracing.com put this number in search:SUM-G1420 try this without your spacer,you may want to put this down first and then the heat insulator and see which works best.

[cletusvandamme]

Originally Posted by 99 to Life

yah that is my eddy intake. I noticed the spacer didn't contour to that opening too well. meaning there was gasket covering those corner pockets. But it seemed to have run fine on a 50 mile trip, then it just went. I'm def gonna try to run it without the spacer and see what I come up with. It definitely helped with my hot starting problem. Here is a pic of what I got.

ya, it probably blew the gasket out on one of the wider parts of the intake as you drove. I bet that is your problem. Take the gasket off, and just put the spacer on with no gasket. See if there is an open space where air is getting in. Looking at that spacer, it says its for a square bore. You'll need that WND-9006 adapter plate to close off that open space on the sides if you want to run that spacer on your spread bore. I know summit says your intake is both spread bore and square bore, but it also says "Carburetor adapter plate sold separately". Im guessing that means you need an adapter if you want to run different carbs.


http://www.summitracing.com/parts/SUM-G1405/

[99 to Life]

thanks guys, what do you think about the 2731 though, it seems to fit that shape of the intake better than the square ones. I'll prolly order both today

[99 to Life]

well I tried the carb adapter and still no luck. I also removed my spacer and still no luck. I then put my 750 edelbrock on and it seemed to have made things better.

So have come to the conclusion there is a vacuum leak within the carb. I got to make sure the power brake port is tight enough as that would be my main guess. Other than that I'm stumped. I had the carb all apart, put some new gaskets in it. New filters and seats. checked my floats again. also put new plunger on the acc pump. also made sure the secondaries are closed at idle. when engine warms up, if you cover the choke it revs up.


any ideas