Holley 1904 Carburetor Rebuild

[John Donnelly]

Originally Posted by Houston

No, i havent checked (or adjusted them). The truck started running progressively worse, I rebuilt the carb a couple months ago, it ran the best it has ever run while I have owned it, then it started down hill again 2 weeks ago.

At the peak, it had a rare dead spot transitioning from idle to full throttle, but had great power and started at the touch of the key. Now it starts a little harder, and does not seem to have the same top end it did before. At the worst, it would back fire through the carb on a consistent basis, and after hauling a load uphill, would stall out at stop sign. When I drive it now, after I shift and try to acclerate, it will almost stall, then chirp the tires as it picks up. Its one of those extremely aggravating problems.

I had this issue with my BG241 in my Travelall. It ended up being dirty fuel system issues.

I fixed it by soaking the hard line between the carburetor and the fuel pump with some muratic acid to get the rust out of it that had appeared in it (be careful with that stuff) the fuel line wasn't like that when I put it together, and then putting a big spin-on fuel filter that NAPA sells on the truck that filters the fuel down to 2 microns.

I had the fuel tank professionally cleaned, but it seems that today's fuel with the ethanol in it promotes some corrosive issues with the fuel tanks in these old trucks. This is my theory, anyway.

I would end up with this fine dust in my fuel filters which would plug the fuel system and lessen the volume of fuel, and then the popping and the flat spot would appear.

It may be that you are experiencing this issue also.

Have you got a fuel filter you can see through or cut open and see what is in it?

-John

[Jay Tabor]

your symptoms are a lean condition- wot= no gas.
so adjust the accelerator pump linkage, so it gives a longer time squirt of gas.
and since its doing it more when engine is cold-put your choke on!

[Houston]

Its been between 95-100 deg here lately, so its not an cold engine problem. It doesnt make any difference if I have driven 20 miles or just started it in the morning after sitting all night. The accelerator pump linkage is fixed, I have considered that. The only adjustment is on the cam, there are two holes, I have it in the hole that gives the biggest shot of gas.

I pulled the carb off again and looked inside, its pristine. No dust or junk. I have the solid fuel filters, but I replaced the it when I did the carb rebuild. I cut open the old one as you suggested John, it had a little rust dust in it, but was probably still flowing at full capacity. The fuel line is a thought though.

[Houston]

Success? No backfire, idles smooth at 500 rpm, and I can smoothly accelerate up my steep drive without bucking. 2 accelerator pumps later. It appears that while they all are new, and appear the same, there are some differences in acclerator pumps. I have an older style 1904 with the metal accel pump cam, it seems to be much more sensitive to small differences in the pump because the cam is much larger and requires the pump rod to move a greater distance. For instance one of the pump rods is a fraction of an inch shorter, so no matter what position the linkage is in the cam doesnt initally engage the pump rod. On the other pump the gasket is cut differently which seems to affect how the diaphragm moves (less gas in each shot). I finally found one that delivers just the right amount of gas (alot).

I think I need to retweak the timing since I moved it around in earlier diagnosis, but over all its a smooth driving machine again.

[tnscouter]

I am in the process of rebuilding and i found that my mixture screw is galled pretty bad. Where can I get a new one?

[Doc Stewart]

IH Only North. Mike Mayben

[ferlandd]

Just completed the tear down of a 1904 for my '65 D1100. Owned it for 2 weeks and bought it not running. Was able to get it running but not for long due to massive leaking at carb. Suspect the accelerator pump since gas was pouring straight out of the hole at the bottom of the recess/housing where the accel pump sits.

Upon disassembly I found that the accel pump spring was actually two shorter springs installed side by side (as opposed to a single spring that was broken). Is this a big deal? Could the combination of 2 springs jack things up? If I need to replace, what are spring constant specs for the replacement or do I just go to an auto parts store or Lowe's and find one that looks about the same...does it matter?
Thanks!

Derek

[John Donnelly]

For Holley restoration parts and rebuilds contact Howell Motorsports.

503-705-1566
503-771-6487

He has extensive OEM carburetor information at his fingertips and many parts sources for new and NOS carburetor parts.

-John

[Thomas]

--_Since it was dug up,

Originally Posted by John Donnelly

I have passed on the Wells kit information several times only to be told by the people needing them that they couldn't get that brand of kit.

The NAPA and GP Sorenson kits appear to be available all over.



-John

---Next time let them know that Wells is also Airtex... which I believe is carried by Advance Auto Parts and maybe Oreilley's, then talk to a competent Manager (not a counter-monkey) and have them order the part... lol. VDP is what it's called through AutoZone if AZ also carries Airtex

---Thanks for your contributions/material again MikeInMobile,AL. I will look for it if I ever need it.

[John Donnelly]

Originally Posted by Thomas

--_Since it was dug up,
---Next time let them know that Wells is also Airtex... which I believe is carried by Advance Auto Parts and maybe Oreilley's, then talk to a competent Manager (not a counter-monkey) and have them order the part... lol. VDP is what it's called through AutoZone if AZ also carries Airtex

I know that Airtex can be Wells, but thank you for that information.

I haven't talked to a "counter-monkey" in about 3 years. I order all my parts via the professional parts supply houses directly and haven't walked into an Autozone (except to help a fellow IH'er buy gear oil) ever in my life. But that is good advice for someone who doesn't have the benefit of being able to order parts that way.

-John