Author Topic: Smokey idle, and surging at cruise speed.  (Read 6281 times)

Offline Mudsport96

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Re: Smokey idle, and surging at cruise speed.
« Reply #15 on: June 24, 2018, 05:28:25 AM »
I'm hoping to get another look at it today with the new gauge I picked up yesterday.
The pump I don't think is anything special just an Autozone house brand if I remember correctly. So hopefully I'll have more info by tonight.
I know I don't need a high output pump because I'd be surprised if this thing makes 350 horsepower with the compression it has. Heck, 300 for that matter.
« Last Edit: June 24, 2018, 05:32:45 AM by Mudsport96 »

Offline 77cruiser

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Re: Smokey idle, and surging at cruise speed.
« Reply #16 on: June 24, 2018, 07:04:51 PM »
I don't know what they do to those parts store pumps but I've heard of several that had too much pressure.
Jim

Offline Mudsport96

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Re: Smokey idle, and surging at cruise speed.
« Reply #17 on: June 25, 2018, 12:36:10 PM »
Well, I was able to check pressure at idle today. The gauge I have only goes to 10psi but it doesn't have needle shake like the other one. It just goes to the stop pin that is after 10psi and sits on the pin.
I think I'm going to need a higher reading gauge, and more hose so I can see what it's doing under load. I took it out for fuel today after checking the pressure. And like always you can cruise at highway speed at 2500rpm and have no issue. Leaving the station I wound it up in first and she shifted, then black smoke out of the pipes and I had to keep the throttle open so she would stay running. I may not even bother checking pressure at speed. I should probably just get a new pump for it and then recheck..

Offline 77cruiser

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Re: Smokey idle, and surging at cruise speed.
« Reply #18 on: July 03, 2018, 07:45:37 AM »
You need a different pump, that pressure is toooooo high.
Jim

Offline von

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Re: Smokey idle, and surging at cruise speed.
« Reply #19 on: July 04, 2018, 02:17:55 AM »
If you have an Airtex pump the high pressure is no surprise. Get an AC Delco pump for the proper pressure. BTDT.

Offline Cliff Ruggles

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Re: Smokey idle, and surging at cruise speed.
« Reply #20 on: July 04, 2018, 04:17:56 AM »
We've had a LOT of complaints in recent years with folks purchasing new fuel pumps from auto parts stores.

Most if not all of them are coming in from off-shore or Mexico and pretty common to have WAY too much fuel pressure. 

Something to check if/when you've complete a carburetor rebuild and are having flooding or running issues even after checking out everything to make sure you did your part correctly.......Cliff

Offline Mudsport96

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Re: Smokey idle, and surging at cruise speed.
« Reply #21 on: July 07, 2018, 08:44:01 AM »
I don't remember exactly what pump is on it, but I'm thinking it's a delco. I've been overly busy with work this week so I haven't had much time to do anything with the car. However, I did notice when checking pressure, that there seemed to be brass in the fuel. I'm wondering if the pump isn't failing internally.

Offline Cliff Ruggles

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Re: Smokey idle, and surging at cruise speed.
« Reply #22 on: July 10, 2018, 02:42:38 AM »
Metal in the fuel isn't a good thing, got to come from someplace and the pump would be the first place to check......

Offline Mudsport96

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Re: Smokey idle, and surging at cruise speed.
« Reply #23 on: August 11, 2018, 04:03:58 PM »
Well, I changed to a new ac delco pump and had the same issue as I had been experiencing.
So to see if it was pressure related I locked the secondaries shut and took it for a hard run. And other than being agonizingly slow, no flooding. Ok so unlock the secondaries and flog it till itdies, shut it off and coast to the side of the road. Pulled the air cleaner and acc. pump rod off. Open the throttle and had fuel pooled in the manifold.
Got it started and went home, and thought on it for a few days. I didn't really change much from what the carb had originally been set up with so I was having a hard time believing it was the carb. So I read through the book again and checked recipe 1... I'm not too far off that. Except I see it recommended hanger k or higher. I had an H in use. Well I put the DR rods on a K hanger I had laying in my parts vin and went for a quick drive before work.
No flooding on the 3 hard runs I did. Is it possible for something as simple as a hanger pulling the rods up too fast to flood out an engine. I will admit this probably isn't even a 320hp application.

Offline Cliff Ruggles

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Re: Smokey idle, and surging at cruise speed.
« Reply #24 on: August 12, 2018, 08:07:21 AM »
Not sure, but I have cured some engines that "puked" all over themselves when going to full throttle with secondary metering rod and hanger changes......Cliff

Offline Mudsport96

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Re: Smokey idle, and surging at cruise speed.
« Reply #25 on: August 12, 2018, 02:17:12 PM »
I think even though I didn't really expect this engine to be a powerhouse, I was trying to go with recipe 2 on the secondary side.
I had DRs and an H hanger on the 1901 and it was fine. Perhaps it was so lean on the primary side that the secondaries were band-aiding the issue.
Actually, now that I think back it was only fair till the secondaries opened. Then it would pull hard. Now that the new carb is on, it was probably too much fuel with the H hanger.