To me a vacuum gauge is to pressure as a multimeter is to electricity. You can see small changes that without it , you would never know. I will be interested on this as I am restoring a 1965 LPB with a rebuilt SD40. Not as far along as you.
**** UPDATE **** SD40 Carburetor issues after rebuild (2 Viewers)
- Thread starter Wadesters
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- carburetor issues rebuild sd40
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I second this advice. It follows the literature in the OE manual which directs the rebuilder to adjust the installed height of the metering rod, although the picture does not look like my SD40 at all. Furthermore, there is a step up rod adjustment made by bending the little u shaped rod under the bowl.
I have just not found the correct carb kit to determine what the installed height should be of the step-up rod and metering rod. Does anyone have the correct height/depth measurements?
middlecalf
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red66toy
Supporting Vendor
The correct SST kit for these early carbs are of course almost impossible to find. It’s a bummer the FSM never gives an actual measurement and just say use the SST. :/
Yep, it's very vague and without the SST, we can only guess. I have played with my SD40 a lot now trying to get the bog away without the choke, especially right when it gets to temperature and it is nearly there but not perfect.
Wadesters
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- Thread starter
- #26
** UPDATE **
First, I appreciate greatly everyones help with this. My issue was none of the suggestions. Lead Mechanic and engine builder drove 3 hours one way here this morning. He went through the normal troubleshooting. Looked and sprayed for manifold leaks, found none. Checked over carburetor and all looked normal. Fired it up and he checked timing and that was good. Next he did something I had not seen. He attached the timing light to each spark plug wire. When he reached plug wire #2 found it was not firing. He used an ohm meter and checked #2 spark plug wire (brand new oem wires). The spark plug wire checked out fine. Then he removed #2 spark plug. These to were brand new. #2 spark plug showed bad even though brand new out of the box (luckily he purchased and installed them before it came back to me). Never heard of a bad spark plug but he said it does happen. Replaced the spark plug and I AM ON THE ROAD DRIVING. Hated for him to come all this way but I would have not thought of that.
Again THANK YOU everyone for the help!!
Final front end assembly begins tomorrow!
First, I appreciate greatly everyones help with this. My issue was none of the suggestions. Lead Mechanic and engine builder drove 3 hours one way here this morning. He went through the normal troubleshooting. Looked and sprayed for manifold leaks, found none. Checked over carburetor and all looked normal. Fired it up and he checked timing and that was good. Next he did something I had not seen. He attached the timing light to each spark plug wire. When he reached plug wire #2 found it was not firing. He used an ohm meter and checked #2 spark plug wire (brand new oem wires). The spark plug wire checked out fine. Then he removed #2 spark plug. These to were brand new. #2 spark plug showed bad even though brand new out of the box (luckily he purchased and installed them before it came back to me). Never heard of a bad spark plug but he said it does happen. Replaced the spark plug and I AM ON THE ROAD DRIVING. Hated for him to come all this way but I would have not thought of that.
Again THANK YOU everyone for the help!!
Final front end assembly begins tomorrow!
middlecalf
SILVER Star
Wow! Great news. I know what I'm doing next with my rig!
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Back in my aviation days I spent a lot of time on a spark plug break down tester. We never put in plugs new or serviced until they passed the test run on the machine. Yes, new anything can be bad or die in a very short time.
middlecalf
SILVER Star
But I wonder why full choke helped? That cylinder was dead either way.
