The Cal-look Lounge

Well, warm weather is back for now, 85F+
And my 48's are doing the same thing again after warm up and shut off and restart

runs fine when "warming up" after first start up in morning
drive it and get engine to temp (170-180F oil)
shut car off, walk away for 10 min
get back in car restart, and idle is all wrong, pop pop pop, flat spots, limping idle, hesitation...

60 idle jet in 120 holder, 2.00 needle valve, floats as per Weber instructions, 7/8 turn out mixture screw
3.0 psi, Red Holley pump and regulator, fuel line is AWAY from headers

I'm ready to roll car off a cliff.

Does the problem ever go away?

ANd if you roll the car off a cliff... let me know where and when and I'll be there with my catcher's mitt  ;)

only when engine cools off.

I looked down throats, I don't see fuel bubbling over when it does this, like you would think.

I don't know what to do.

Have you thought of insulating the fuel line under the car?

The Pump is by the tank? What about the Regulator??

pump is opposite brake master cylinder
AN-6 line through tunnel, then routes to RH side, up above trans, near where Z bar goes through body, then into engine comp through body (Rh in front of RH 48IDA)
regulator is on firewall in front of fan shroud, near decklid spring.

I don't think line is getting hot, but I will try isolating that possibility with a cold rag or something next time it does this and I am ready to go at it with a sledgehammer.

ok and since the reg is on the motor end the line should be pressured enough to stop vapor lock.

It sounds like some sore of heat soak problem.

most frustating bit of this.... it hasn't ALWAYS done it.
started off and on a few years back

I wonder if it has to do with the "new" gas?

Only other thing I can think of is this: when I blew my ring gear out at Sac one of the guys that "helped" me pull my car apart decided to blow compressed air down the jet cavities. Dumb move, as that squashed one of my floats. A year later when i got car going again, I found the squashed float in the carb, and replaced it with new one. Now that I sit here and rack my brain, I think the new float had another tab on it (besides the one that contacts needle valve). If the float has this extra tab (near float bowl wall) and I never "adjusted it" could it somehow be causing this? Does gasoline expand when it gets hot?

I am willing to try anything at this point.....   how's that CB injection?

hmmm I think I'd check the float out. Usually the second tab would be to limit downward travel.

right.... it would hit either the needle valve (down travel)  OR the wall of float bowl (Up)
depending on where tab is bent

what would make fuel level "drop" after the car sits there hot? Or what would make fuel supply dwindle after car sits warmed up?

Sounds Like its Time for a Set of 42 DCNF's  ;D they always run good

Can you see that the level is down in the float bowls?

Naw, I guess I could look down the vent hole after the car sits hot and see WTF is going on.

I am ready to hire somebody to come exorcise this gremlin from my life.

May I recommend "The Blessing of the Cars" Car Show?  ;D ;D

Held the last weekend in July at Hansen Dam.

Get you car blessed by a Catholic Priest,  ;)

Jim, I'm inclined to agree with Rick about a heat sink issue. Have you checked how hot the manifolds are after the car is shut down for a little while? I've noticed problems like this also when they change from winter to summer gas or the opposite, and the weather changes back to hot with winter gas, or cold with summer gas, if you get what I mean. Also, the alcohol in the gas turns into this shitty white residue that can leave a needle valve open enough to seep. Food for thought....

thanks guys, back to the fricking garage instead of the driver's seat.  ::)

                                                   The new monorail at Disneyland is a big piece of shit. The other day they had 19 nuns visiting from Rome. They asked the Nuns to bless the new Monorail and they were promptly able to drive the thing around the park without a hitch. They are now going to be able to put it into full service sooner than expected.

John, I'd like to pick your brain.... I'll try to call you this wekend.  ;)

Give me a holler!!

When was the last time you drained your tank? Does it matter if the tank is full or half full or empty? Did this start after you parked your car while you took a break from VWs a few years ago?

Just a thought.

--louis

Except in high speed, long sweeping turns.

                                                Or if you use a 42 or bigger venturi....

Jim, get yourself a piece of 1/8" Al welding rod, about 3" long.  Insert it down the vent hole until it contacts the top of the float, but does not push it down.  Make a mark where it is.  Compare to the other side.  Repeat when hot.

Gas expands by a huge amount when heated.  It's rate is 4 times that of water, and 13 times more than aluminum!

I know it might be a longshot, but my old mustang used to act like that on hot days and turned out that the fuel tank vent was plugged. I used to have to pop the gascap off to let out the pressure and it would start. It might be worht a shot.

Just a thought: I had about the same problem with IDF's as soon as i switched to the aluminum case....Heat. After i mounted some phenolic spacers between the manifolds and the carbs, the problem was gone.

With my short manifolds for the IDA's i'm thinking of stacking 2 spacers per carb on this thing.

Hey Jim,

Where on the Motor is your Fuel Regulator installed...???

Frank

COOL, thanks Bruce, I will try to get a look see this weekend.  Maybe I can at least see if level is going up or down and then the fun part..... finding out the culprit. Like I've said, this hasn't always happened.

Theories:

2nd float tab limiting travel one way or the other (I don't know which without going inside carb and looking)

Holley pump and regulator causing problems (yes I have had problems in the past) or lines between regulator and carbs getting heat sokaed? Sometimes when engine is off, after warm up, I can hear "something" going on inside of Webers, but as I mentioned I do not see dribble on top of throttle plates. And if it was flooding, wouldn't the thing run pig rich when fired? it doesn't it does the exact opposite. It acts as if the mixture screws are closed or near closed. In fact, if I go back and reset mixtures as this is happening, I can richen it up, but then it runs like crap too....just doesn't pop.

fuel formula? then why isn't everyone else having this trouble in CA?


where do I buy phenolic spacers for 48IDAs I can't find them anywhere.

Hi Frank, thanks..... it is on firewall in front of fan housing, centered between carbs.

The power of the internet! Look here http://www.mazdatrix.com/r-11.htm (http://www.mazdatrix.com/r-11.htm)

Just to mention......   I did try a completely separate pair of carbs on my car last summer... same jetting and vents, but different carbs.... SAME PROBLEM

 >:( >:(

I had a similar problem with my much smaller 40idfs there was some sort of vacuum in the fuel tank and got only got cured when I increased the vent size to the fuel tank. ???

sounds like I am chasing my tail with the carbs.... need to look upstream. Thanks...more ideas? Please share.
Beers for all!

If you already swapped out carbs, why don't you try to Swap Cars...  :P  ;D ;D

Maybe it has a Bad Karma...try talking to her in a different way, always helped with my Car... ;) ;D ;D

Do I get a Beer Now Jim... ::) ;D ;D

Frank

oh brother   ::)


 ;D

Or you can Ship Your Motor over to me...I'll Test it in my Car this Summer... ;) ;D ;D

Frank

Then it must be the engine... as in heat...
My guess

Deadhead or bypass regulator?

dead head red Holley

Didn't you have a problem with the msd box the last time this happened?

tw

Could very well be a vapor lock issue.  I run a mallory bypass unit, really takes the load off the pump and insures cool vapor free fuel to the engine.


Good point!    It can be a real bitch determining is it a fuel or ignition problem.  Hell sometimes it's both :o

JIm, I curious if when you let the car sit for 10 min, do you have the deck lid OPEN or CLOSED?

Next time you park it, just take the manifolds and carbs off and keep them in the cooler with all the beer. Problem solved. :D ;)

I am watching this thread to see your out come. Alot of cars do this after sitting. I know of v8 too. I always thaught vapor lock. Maybe do a test and sit bags of ice around the manifolds when you let it sit. See what happens then. :-[ :-\
See ya.

i think the carbs are geting to hot, put a 7-10mm pertinax spacer between mainfold and carb.

dirk zeyen

Hey Jim,
   Could it maybe be an intake leak? possible different cooling characteristics between head and manifolds? does that make any sense? I have been having lots of intake leak probs myself lately and the issues arise after the engine has warmed up. It could be worth a shot to spray a little brake cleaner at the base of the manifolds while engine is running to see if RPM's change, or just pull the manifolds and do a check of the gaskets. Give it a little rub and a kiss and talk nice to it too....  and keep the IDA's. you'll get it.  Jason

i 2nd what fdk/hurry said  espealiy in an extra hot engine compartment. what is it jim with your hot running engines  ;) what are you running one of them rappid roast behind the fan  :P try the phonolic of coarse it would have to be some what thin if you had tall scat tracks. good luck to ya my freind. UD.

Hi Jim, I order my phenolic spacers from Custom & Speed Parts here in Europe. Let me know if i can help.

well I appreciate all the suggestions. Honestly the carbs and manifolds don't get that hot. I have a milivoltmeter with temp sensor I will go take a reading next time it gets warm out around here.
I think I need to look upstream though.... pump, filter, regulator, gauge.... 

what I may try is next time I re-start on a warm day, and it starts this crap, is crank open the regulator, above and beyond what the carbs will take, and see if it send the problem the "other" way (Rich)

thanks again... if I figure it out I will let you know.

So Jim,
some progress?

Hi ruff, thanks for asking... and the answer is "maybe"

I did what i said I was going to do in above post....  last week I resorted to 70 idle jets (!) just to experiment and see it if i could "outrich" the issue. As I expected, the car ran horribly on the 70 idles no matter what I did with main jet size (of course, too large of jets with 70's would probably be optimum for "correct" idle jets"). Anyway, I did take car on a 40 mile trip on freeways last weekend, then stopped to get haircut, then restarted car and it still showed signs of being leaner (popping at idle, very slight hesitation again). No way I was going to keep running around with 70 idles (you cannot believe how horribly it ran during the overlap of idle and main circuit...  ). I thought I would try a spare set of old idle air holders, and drill them open to 135... still way to sluggish and rich, and still that was going to nothing to cure the warm start up and idle.
Last night I did do some more snooping around. First I went back to stock 120 kair idle holders, and 60 idle jets. Idle is better, of course, transition to main circuit is much cleaner, and i did drive it this morning to work, as another "test session" (main reason I drive my Bug to work and on errands so often is to "test" mods and service work on car). The other, more important change I made last night, was I turned fuel pressure up to an "indicated" nearly 6psi on VDO mechanical pressure gauge @ regulator.... which resulted (unexpectedly) in no foul running or dribbling from nozzles in throats. Reason I did this was...well reasonS were the adjusting screw on regulator was nearly screwed out all the way to get indicated 3.0psi, which seemed odd. Secondly, I have had numerous issues with Holley pumps and regulators over the last 17-18 years, never been stranded, but i have had pressure and volume issues (maybe kafercup remembers my regulator/gauge issue that hot day we went to Point Reyes? ;D). I think, at this point, the culprit is the gauge is lying to me. I don't think stock Weber needle valves can withstand "6 psi" without flooding bowls. Before I closed the decklid last night, I lowered the regulator pressure to an "indicated" 4.5psi and left it. In about a half hour I am going to take my lunch and go warm the thing up on a test and try things out. Will let you know.
Thanks  :)

lets hope its just the gauge then ..
i ll keep my fingers crossed  8)

Any (good) news Jim ?

You can get the holley regs that return to the tank, (Bypass) so the fuel isnt stopped. when the pump is on the fuel always returns to the tank, this will help keep the fuel cool. so and vapour locks get pumped out.


Might be worth a try.


Theres always fuel injection ;)

Jim,

I can't stand it anymore................... EFI  :D

ok, update

found one float is the later type with the down-travel limit tab. After looking at this for a half hour or so tonight I saw what "might" be happening. When the carb cover is bolted up, the needle valve jerks float "back" (which is actually "up"), closing needle valve partway, though I can't see by how much. I swapped this float out for an older type, without tab there. Also RESET floats again

6.0mm above carb body (crest of float)
0.953" (24.2mm) from body to needle valve tab
25.0" needle valve height.

Spent about an hour getting the floats as close to perfect as I could with depth mike.

It's 1:20am so I am not about to go fire it up.

More tomorrow.

Next time you're in there, check to see if the float can drag against the wall of the float chamber.  I have seen a couple like that.

I am very pleased to report..............


after 8 fricking years of fighting this and chasing my tail...... the goddamn thing is FIXED!

it WAS the float tab against the needle. Drove the car today (92F out) for a good 30-40 min, got oil to 180-190F, went shopping for beverages, come out from store, and no more lean idle, no more huge hole and lean snag in transition.... it runs well. What a weight off of me..... I was ready to take drastic measures....

My last suspicion before I found the float....  that hot air off Setrab fan-cooler was cooking AN-6 fuel hose under car, so I was sizing up making an air dam for the cooler.... which I still might anyway  ::)

Now I only want to finalize emulsion tubes, F11? F2? F4? which one enrichens accleration at mid rpm?

Thanks to everybody.... 
Jim

Glad to hear that Jim!
Nice one :)

Good job Jim :)

Great Jim! So I should put away my catcher's mitt then??  ;D ;D

More driving and no signs of the dreaded hot-start miss.

 :)

Cool! Aren't they great when they run right?  ;D

--louis

more driving this week.... plus found pressure gauge was waaaaaay off (new gauge shows setting on reg was only sending 1.5psi to carbs [indicated 4.5 on old gauge]) got it set correctly and car runs even better. It's a happy car again.

Very good news! ;D

Good news Jim!
Glad you worked it out