More troubleshooting help needed..., this is getting not so much fun |
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More troubleshooting help needed..., this is getting not so much fun |
lotus_65 |
May 8 2007, 09:42 AM
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#1
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Senior Member Group: Members Posts: 1,608 Joined: 21-March 05 From: minneapolis, mn Member No.: 3,795 Region Association: Northstar Region |
'74 2056 + dual 40's, mallory + blue coil internally ballasted.
So, because I just can't get the carbs right, I had a mechanic do it. The car ran great for about 300 miles and then started missing. I have gone through ignition, tested or swapped with known working replacements and the miss remains. I tested the mallory according to the instructions here: unilite module testing. It passed all those checks. I did a fuel flow test to the carbs. flow at under 1lb is a little shy to the 3&4 side, but at 2, where I run the regulator normally it's effectively even flow. I pressurized the system and got 3lb's max (my return line is calibrated for that). Both carbs seem to be feeding fuel appropriately. I can unplug wires 1&2, and the car still idles @<300rpm. Unplugging either 3 or 4 causes the engine to die. Here's the weird part: I can almost get the idle correct by holding the plug wires on 1 & 2 about a quarter inch from the tops of the plugs. That is to say that the idle comes up momentarily, and waivers depending on if ignition gets through the plug in time. I've replaced more plugs in the last year than I'd care to admit, and I broke my CSOB plug wrench or else I would have a report on those too. I can't see how they'd go bad though. Ignition or fuel? TIA for the help! Paul 952.451.5205 |
904svo |
May 8 2007, 10:17 AM
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#2
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904SVO Group: Members Posts: 1,118 Joined: 17-November 05 From: Woodstock,Georgia Member No.: 5,146 |
Sounds like the carburator is out of sync at idle, try turning up the idle screw in
on the carb on cylinder 1&2 if that smooth out your problem the carbs are out of sync get a Uni-sync and set the flow rate the same on both sides of the carbs at idle. |
lotus_65 |
May 8 2007, 10:41 AM
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#3
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Senior Member Group: Members Posts: 1,608 Joined: 21-March 05 From: minneapolis, mn Member No.: 3,795 Region Association: Northstar Region |
Actually, before I started messing with the carbs I ran to the flaps and paid too much for a so-so plug socket. I just swapped the 1&2 plugs for some older ones in the used bucket.
Problem solved. Although, it brings up something I have come to notice: Everytime I chose to change the plugs, the 1&2 look wet and black, as opposed to 3&4, which look dry and grey at the tips of the nodes. ?~ Am I fouling the 1&2 sides on a regular basis, and am I not solving an air/fuel ratio issue by buying a pro to sync my carbs... |
So.Cal.914 |
May 8 2007, 11:03 AM
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#4
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"...And it has a front trunk too." Group: Members Posts: 6,588 Joined: 15-February 04 From: Low Desert, CA./ Hills of N.J. Member No.: 1,658 Region Association: None |
Sounds like your running rich on 1&2, that would foul your plugs. What do 3&4
look like? |
lotus_65 |
May 8 2007, 11:09 AM
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#5
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Senior Member Group: Members Posts: 1,608 Joined: 21-March 05 From: minneapolis, mn Member No.: 3,795 Region Association: Northstar Region |
3&4 look gud. This is a long-standing issue with this car. 1&2 look wet, 3&4 look good.
I think I've been getting "the treatment" from my carb guy... |
toon1 |
May 8 2007, 11:21 AM
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#6
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Senior Member Group: Members Posts: 1,849 Joined: 29-October 05 From: tracy,ca Member No.: 5,022 |
I'm taking a wild assed guess, but, 3&4 are the hotter running cylinders, it's possible that the extra heat is making that side burn better and the colder side rich.
Again, a wild assed guess |
rhodyguy |
May 8 2007, 11:21 AM
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#7
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,082 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
do you own the synconometer that has the numbered scale as opposed to the ball in a tube type? if you do i'll continue...
k |
lotus_65 |
May 8 2007, 12:32 PM
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#8
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Senior Member Group: Members Posts: 1,608 Joined: 21-March 05 From: minneapolis, mn Member No.: 3,795 Region Association: Northstar Region |
it's at the top of the list now, rhodyguy.
I'm going back to my guy and ask him about this. It's something he should fix gratis I'd hope. Paul |
iamchappy |
May 8 2007, 12:45 PM
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#9
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It all happens so fast! Group: Members Posts: 4,893 Joined: 5-November 03 From: minnetonka, mn Member No.: 1,315 Region Association: Upper MidWest |
Check your plug wires and your coil wire.
If you need a unisyn carb gauge I have a few laying around stop by and pick it up if you need it. I am willing to bet it's the wires though, if the carbs were tuned not long ago they still should be. |
lotus_65 |
May 8 2007, 01:05 PM
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#10
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Senior Member Group: Members Posts: 1,608 Joined: 21-March 05 From: minneapolis, mn Member No.: 3,795 Region Association: Northstar Region |
Thanks, Chappy. I swapped everything except mallory with known-good items, mostly off Dave-O's car (which runs great). I think ignition is o.k. and the rich carb is causing fouling (something I noticed 2 years ago, but I can't get an ear from anyone about that...)
(IMG:style_emoticons/default/dry.gif) Hey, do you know Greg Smith @ Smith Imports? He's right in town down Shady Oak from you. He is who sync'd them. I think he should make it right. Paul |
akellym |
May 8 2007, 01:14 PM
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#11
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Eyes Of The Deep Battle Group: Members Posts: 597 Joined: 25-July 04 From: Annandale, MN Member No.: 2,395 Region Association: Northstar Region |
If you ever need any help, there's plenty of room at my garage.
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lotus_65 |
May 8 2007, 01:19 PM
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#12
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Senior Member Group: Members Posts: 1,608 Joined: 21-March 05 From: minneapolis, mn Member No.: 3,795 Region Association: Northstar Region |
Thanks, Kelly.
How are you? Is the car getting it's new paint yet? Hopefully we'll get some type of gathering this year, eh? Paul |
akellym |
May 8 2007, 01:24 PM
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#13
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Eyes Of The Deep Battle Group: Members Posts: 597 Joined: 25-July 04 From: Annandale, MN Member No.: 2,395 Region Association: Northstar Region |
No paint yet. I want to finish this season, so it will go in late Oct this year. There's a concours on May 20th at 1000 at the plymouth radison. The Nord Stern PCA is hosting the "Inter-Marque Spring Kick Off". I'll be there, so if any of you guys are in the area swing by.
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lotus_65 |
May 8 2007, 02:35 PM
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#14
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Senior Member Group: Members Posts: 1,608 Joined: 21-March 05 From: minneapolis, mn Member No.: 3,795 Region Association: Northstar Region |
I haven't joined Nord Stern but I'll come by, if you don't think they'll ask me to get out!
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akellym |
May 8 2007, 02:51 PM
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#15
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Eyes Of The Deep Battle Group: Members Posts: 597 Joined: 25-July 04 From: Annandale, MN Member No.: 2,395 Region Association: Northstar Region |
It's open to the public I believe, you just have to join to show a car.
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iamchappy |
May 8 2007, 02:55 PM
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#16
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It all happens so fast! Group: Members Posts: 4,893 Joined: 5-November 03 From: minnetonka, mn Member No.: 1,315 Region Association: Upper MidWest |
Greg Smith knows what he is doing, been around a long time is a good friend of Rick Moe(Nurburing).
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lotus_65 |
May 8 2007, 03:26 PM
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#17
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Senior Member Group: Members Posts: 1,608 Joined: 21-March 05 From: minneapolis, mn Member No.: 3,795 Region Association: Northstar Region |
Yep, I think he does know a fair amount. I just spoke with him. We agree that either the carb is allowing unburned gas into the cylinder or the ignition isn't strong enough to fully ignite the mix. he gave me a few things to check:
Double check resistance in the 1&2 wires, if good then Install new needle and seat in that carb and check float level. Then maybe go to a hotter plug... but then we'd want to add head temp gauges to monitor. I checked the floats for leaks a couple months ago, and they passed. Anything else? Paul |
iamchappy |
May 8 2007, 04:33 PM
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#18
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It all happens so fast! Group: Members Posts: 4,893 Joined: 5-November 03 From: minnetonka, mn Member No.: 1,315 Region Association: Upper MidWest |
No, but your still welcome to the extra carb syncer I have if you want it.
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Carlitos Way |
May 8 2007, 04:51 PM
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#19
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I did it MY WAY Group: Members Posts: 1,337 Joined: 14-September 04 From: Simi Valley, CA Member No.: 2,757 Region Association: Southern California |
I was once told (and I'm not sure if this is correct or not), that you should have equal length hoses into both carburetors. in other words, you should split your line to a T and feed both carbs from there with equal length hoses. MIght be a relatively simple and inexpensive solution to your trouble.
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Gint |
May 8 2007, 05:55 PM
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#20
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Mike Ginter Group: Admin Posts: 16,075 Joined: 26-December 02 From: Denver CO. Member No.: 20 Region Association: Rocky Mountains |
I was once told (and I'm not sure if this is correct or not), that you should have equal length hoses into both carburetors. in other words, you should split your line to a T and feed both carbs from there with equal length hoses. MIght be a relatively simple and inexpensive solution to your trouble. I need to do that very thing. I just recently got rid of the single priogressive carb and replaced it with dual 40IDFs. My fuel hose tees at the right carb with a much longer hose going over to the left carb. The car stutters at steady throttle. When starting the car imediately after I rebuilt the carbs last week, it wanted to run but couldn't quite get it done. I checked the carbs for fuel squiting, first the right and then the left. The right carb float bowl had filled up and was squirting fuel, while the left carb was not. And this was after trying a good deal. I would have thought that the left carb float bowl was full. I primed the left carb and she fired right up. The moral? The car still sputters a bit at steady throttle. Not as bad, but it still needs something. One of my first thoughts was to replace all of the fuel line and make T in the middle of the two carbs with equal length lines to the individual carbs. It may be helpful, and it may not, but it's going to be done reagrdless. YMMV... |
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