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I'll start with some stats:

2275 Type I, New motor

44 Webers, 150 Main, 65 Idle, 200 air  I live at 2500' and drive between 2000-4000'.

 

I adjusted the valves to .0 for the first time, and tightened the belt by one shim. Went for a few drives. Drove great except for some stumbling at about 2500 rpms. I figured I'd need to adjust the carbs at some time.

 

I changed the oil, filter, and sump cover with a drain plug. 20/50 Brad Penn oil, 1334 Napa Gold filter. It was the Napa equivalent of the Bosch 3310 that came on the car. Then the car sat for a few weeks while the Rainamagedon took over the weather outside.

 

Today, finally a clear day. I start it up and it doesn't sound right. Hard to explain, but it wasn't as smooth as it was before. Every minute of so, at idle, the tone changed. The exhaust seemed to be a touch more vigorous for a split second. After it was warm, I took it out. The power wasn't there so I turned around and headed back home.

 

I removed the Idle, and Main jets and gave them a spray and blew them out with air. I took it out again, but the same.

I checked the timing and it was at about 29-30, so I adjusted it to 28 degrees.

 

What should I check next? What could possibly change with the car sitting?

 

Thanks,

CG

 

Original Post

Does it have points or an electronic replacement? If points, check point gap, and make sure there is distributor grease packed against the block, on the leading edge so the grease doesn't get thrown around and foul the points. Was the timing adjusted to 28' originally? How much did it change when you adjusted the valves? Do you have aluminum or chromoly pushrods? Did you happen to notice any glitter (fine aluminum pieces) on the drain plate when you changed the oil?

 

What camshaft, rockers, heads and exhaust does it have? Compression ratio? 

 

PS- Oh yeah; what Lane said too.

Last edited by ALB

82mm forged crank, I don't know make

Engle FK8 Cam

Scat lifters that have been refinished, polished and parkerized

1/4 rockers, Unknown make

Unknown heads, but something had a Stage 1 port and polish

AA 94 X 82MM P/L SET ??

Chromoly pushrods

Compufire

NGK D7ea, I just removed one and it was black and sooty looking, Too rich?

No glitter

I didn't make note of previous timing.

1.5" stainless exhaust with Magnaflows

This is a Seduction build. Motor was built by Competition Engineering in Phoenix.

 

 

I guess I should reach out to CE for some more details. The info on my invoice was minimal.

 

I'll test the coil tonight.

A $20 compression tester can show if a valve spring is broken or keeper popped off, push rod not seated, valve or valve seat gone, piston ring broken.  A low compression on one piston or a side pin points issue that needs to be addressed. It gives you peace of mind that innards are in good shape so you can concentrate on peripherals like distributer and carbs.

 

Actron CP7826 - Actron Compression Test Kits

Danny,

 

About the points eliminator set screw.  after the autocross at Carlisle this spring, my car was acting poorly, missing at high speed.  Ran and could be driven, but was poor.  I dis a few things on the engine, not the least was to buy a new coil and Pertronix unit.  Old device was (as listed here) Compufire.  When I went to replace the old Compufire module with the new Pertronix (all made by the same compant, as far as I can tell) I found the set screw loose.  Hmmmm . . .  ANyway, the new coils was installed and the new Pertronix, with a very tight set screw, AND some blue Loktite. I can report that the engine started almost before I touched the key, I mean instantly, after sitting for a few months. Not sure what was exactly wrong before, but all is jake now. Runs good, ,strong, smooth, and winds up tight, like it should. I do not know what Carlos is dealing with here, but it very well could be ignition.  BTW, this "total rebuild" of my ignition cost less than $100 - a new blue coil and the Pertronix.  Simple.

When I got home and finished dinner, I went out and did a few things:

 

-Points eliminator screw was tight. I also chased the wires to make sure they were secure. Is there a way to check the ohms on this thing?

-I checked the ohms on the coil and it checks out.

-I pulled the plugs, they were sooty and black. I cleaned and checked the gap and reinstalled. The gap was about .76mm. Is that the usual gap?

-I couldn't tell if there's any fuel in the oil, but it is fresh and the level is between the two lines. Actually it's 3/4 up from the bottom line. I was going to unscrew the filter to let out a touch, but I might just pull the valve covers off and check the valves, just to be sure.

 

I didn't start it up tonight just to be courteous to the few neighbors that live near by. I kinda live in a cove, and sound travels very well. Maybe I'll wake them up tomorrow morning before I go to work.

I'VE GOT THE POWER!

 

I didn't wake up the neighbors, but after my ride today, I checked the valves and springs, warmed it up and rechecked the timing. All good. I even went by the parts store and picked up an old school condenser and points just in case, I wanted a set anyway. I took off for a test drive, and now I'm back to terrorizing the roads. Bwahahaha!

 

I don't know what I did, sometimes messing with too many things all at once is not a good way to find out what the problem is. The only significant thing I did was clean the plugs. It could be some intermittent ignition thing, oh happy day. Well if it happens again, I'll drop the regular points and condenser in and go from there.

 

It still stumbles some around 2500rpms. I need to either learn this carb thing or find a local weber whisperer.

 

 

Car runs fine.

 

Car sits for a week in Rainamagedon.

 

Car no run fine.

 

Car dries out for a few days.

 

Car runs fine.

 

Carlos, I don't think it's anything terribly complicated. I would look at anything in the ignition system that could be affected by too much moisture in the air - plug wires, dizzy cap, plug wires, rotor, and oh yeah - plug wires.

 

Bad plug wires look exactly the same as good ones, but are cheap to replace.

 

Happy motoring.

 

 

Originally Posted by Carlos G:

I'VE GOT THE POWER!

 

I didn't wake up the neighbors, but after my ride today, I checked the valves and springs, warmed it up and rechecked the timing. All good. I even went by the parts store and picked up an old school condenser and points just in case, I wanted a set anyway. I took off for a test drive, and now I'm back to terrorizing the roads. Bwahahaha!

 

I don't know what I did, sometimes messing with too many things all at once is not a good way to find out what the problem is. The only significant thing I did was clean the plugs. It could be some intermittent ignition thing, oh happy day. Well if it happens again, I'll drop the regular points and condenser in and go from there.

 

It still stumbles some around 2500rpms. I need to either learn this carb thing or find a local weber whisperer.

 

 

Sooty black plugs not good. 65 idles might be a little rich. My car also stumbles like yours, engine builder told me the venturis in the 44s are a little too big. He said if I went down one size it would fix the stumble but cost 3 or 4 hp. I'm gonna live with it. Your engine is a lot bigger than mine so maybe the venturi size is good for your engine. Just a guess.  Bruce (air cooled) had the same stumble as mine and changed for the smaller Venturi and fixed it. Both ours are 2110s though.

Carlos,

 

When you start the car in the morning or when the engine is dead cold do you have to keep moving the throttle a little so the accelerator pumps keep the engine running or does it sit and idle OK once it starts without touching the throttle?  If it stays running all right then the idle is too rich. This is probably why your plugs are black.

Al, I know why the smaller venturi will work better, higher air velocity is the idea. I don't know much about Webers, I'm a Holley guy so I'm wondering if I can get rid of that stumble by playing with the accelerator pumps?  If this won't work then at some time I could switch the venturis out. I changed the main jets from 155 to 145 and it made a huge difference in mileage, from about 10mpg to about 20 but it's still not where it should be. Sorry I hope I didn't hijack your thread Carlos.

One contributing factor to a LOT of weather misfire problems is the use of multiple "resistor" components.  That would be plugs, secondary cables, rotors and plugs.

Resistance is used to silence radio frequency interference caused by the ignition system.  The trick is you only need one single component type to achieve this.

So if you have a resistor rotor, cables, plugs, or any combination of two or more, it is far easier for a damp cap surface or coil face to cross fire or ground out.

 

This was a BIG problem for GM in the early 70's...

Yeah Danny, 36mm vents are about right for the engine size and rpm range, especially for the most power "under the curve" (throughout the rpm range) and not just the top end. Depending on the heads (Carlos said he didn't know exactly what they were, but had a "stage 1 p&p), he may even be able to go a bit bigger, but if it has good power throughout the rpm range (goes to 6500 with power) and Carlos likes the way it drives, it may not be worth messing with.

 

Carlos- Have you been able to reach CE and find out anything more? It would be nice to know exactly what heads are on it. Oh- just went up and re-read your parts list, Carlos, and you mentioned a 1 1/2" exhaust, so I'll bet the heads are Tims Stage 1's with 40x35mm valves. Do you know the compression ratio?

 

Frank- Adjust the accelerator pumps and see if it helps. Great to hear going down in main jet size improved the mileage; did you notice an increase in power at all? Have you tried a size smaller idle jets yet?

 

 

 

Last edited by ALB
Originally Posted by ALB:

Yeah Danny, 36mm vents are about right for the engine size and rpm range, especially for the most power "under the curve" (throughout the rpm range) and not just the top end. Depending on the heads (Carlos said he didn't know exactly what they were, but had a "stage 1 p&p), he may even be able to go a bit bigger, but if it has good power throughout the rpm range (goes to 6500 with power) and Carlos likes the way it drives, it may not be worth messing with.

 

Carlos- Have you been able to reach CE and find out anything more? It would be nice to know exactly what heads are on it. Oh- just went up and re-read your parts list, Carlos, and you mentioned a 1 1/2" exhaust, so I'll bet the heads are Tims Stage 1's with 40x35mm valves. Do you know the compression ratio?

 

Frank- Adjust the accelerator pumps and see if it helps. Great to hear going down in main jet size improved the mileage; did you notice an increase in power at all? Have you tried a size smaller idle jets yet?

 

 

 

One of these days I'm going to go from the 60s down to 55s and see what that does. Mine acts just like Carlos car maybe not quite as rich. It's pretty close now, I need to look at a couple of plugs to see how rich.  Then mess with the accelerator pumps. One big improvement was going from a Mister Gasket cheap fuel regulator where pressure was all over the place to a Malpassi Regulator.  Now it holds exactly at 2.5 psi all the time and is noticeably smoother at low speeds.

I've ordered an air flow meter and a set of idle jets one size smaller than what I have. I did some more investigating, and found that my idle jets are actually 55s, mains are 150, and airs are 220.

 

When I get that stuff in I'm going to sit down with Danny's printed out "How to adjust Webers" and have a serious talk with my Webers. Two shall enter, one will leave.

 

Where would I find the fuel regulator on my Vintage Spyder? In my travels through my car, I have yet to see something that looks like it. I'm going to drop a line to Daniel and see if he even installed one. I'll drop a line to Dan at CE about other details also.

I'll bet a case of beer that Carlos has a self-regulated electric pump up in the front.

 

I refuse to use regulators. I have a self-regulated rotary pump, it is always just under 3.5 lbs. Webers like 3 to 3.5. No more, no less. Solexes like 1.5 lbs. Period! No more than 2 for sure, the float valves get overwhelmed.

 

I bought a stack of 10 fuel pump gaskets, I ended up with 7 gaskets on my friend's sand rail with 2 35mm single throat PDSIT Solexes, and 1.6 psi.

 

I've seen 6 psi with a stock mechanical pump and one gasket under the phenolic spacer and one under the pump, FYI. I guess what I'm saying is YOU NEED TO MEASURE TO REALLY KNOW. Otherwise you're guessing.

 

FPcopo: I started with 60s, peak warm idle leaned to about 1 1/8 to 1 1/4 turns.

 

55s were too lean, it fell on it's face down low. 57.5 are close to perfect(mid sizes are available)

 

Carlos, your jets may be perfect, but you might just need a good synch and tune....

IT'S ALIVE!

 

It's idling pretty smooth at 900 rpms. #1 cylinder needed a 1 1/4 turn out on the bypass screw to make it sync with #2. I'll might look into this further. #4 needed a slight turn out on the bypass. I also adjusted the angle of the downrods on the linkage to get them almost the same. I'm going to work on this some more, and get them the same.

 

It is like a dance, like Danny says, jumping from one side to the other with the engine getting smoother with every jump.

 

I don't know how many turns out each idle speed, or idle mixture screws are now. I'm skeerd to find out. I need to get it out on the road first. It got dark when I finished. I did start with 1.5 turns out with the mixture screws, and I only turned them in.

 

I did find out why, after I turned the idle mixture screws in and then back out to where they were, my engine ran like ****. Apparently I wasn't gentle enough when I turned them in. Boy, do you have to be gentle. The seats stuck on the mixture screws on #2 and 3. I was wondering why my two previous attempts at tuning the carbs failed. I was able to remove them from the screws and reseat them. I then cleaned and then polished the end of the screws with some 600 and reinstalled them. I don't know if this was the "right" way, but it seemed to work.

 

Wow, I'm learning some **** now.

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