have tp pump gas pedal after hwy cruising

[scoutboy74]

Wow. My eyes need a hit off the oxygen mask. I sure hate to let a trivial thing like facts get in the way of good story telling, but since the carb in question has not been properly identified, maybe we should tap the brake pedal until that has been accomplished. So far I can't see any tidbits which would lead one to presume that it is an aftermarket model, or that it has been recently serviced. Much time was devoted to bashing and bemoaning an unspecified aftermarket carb model in the preceding post, perhaps all for not if the carb in question turns out to be an original list number. If that does end up being the case, I hope the contributor will see fit to remove all portions which do not directly pertain to the OP's current carb model and reported issue, of which there is potentially a vast amount.

[Thomas]

Originally Posted by scoutboy74

Wow. My eyes need a hit off the oxygen mask. I sure hate to let a trivial thing like facts get in the way of good story telling, but since the carb in question has not been properly identified, maybe we should tap the brake pedal until that has been accomplished. So far I can't see any tidbits which would lead one to presume that it is an aftermarket model, or that it has been recently serviced. Much time was devoted to bashing and bemoaning an unspecified aftermarket carb model in the preceding post, perhaps all for not if the carb in question turns out to be an original list number. If that does end up being the case, I hope the contributor will see fit to remove all portions which do not directly pertain to the OP's current carb model and reported issue, of which there is potentially a vast amount.

here we go again.

[scoutboy74]

Funny, that's the same thing I thought even before I began typing last night. The strike over is a nice touch, but you placed it over the wrong post. Here, let me show you what you should have done:

Originally Posted by Thomas

---Vacuum leak at base of carburetor. What Base Plate Gasket and is it new? Possibly even that the carb mounting screws were overtightened. They only go on with some ridiculously small amount like 14 lb-in. Basically, it's hand tight, not 1/4 grunt. Holley should have given you those specs, along with a torque sequence. If they didn't they're slacking, more than I'd believe, and that'd be something awful*

---When you call and wait the hour+ to talk to someone, tell them you want torque specs for every fastener on their new 2300s and ask if it's the same as the old. If someone says they don't have any, tell them you want to talk to a supervisor. When you reach someone who actually knows WTH they're talking about, you have an email for them to send the specs to; They have an email to send them from.

-Amazing how the "pros" don't think of a dashpot!(,)

---It could also be sticky advance weights in the distributor, but you might simply be missing throttle decel components (like a dashpot). While not everyone runs such components, that does not mean they're not right for you. If your truck is an M/T & idles at 500-550 RPM... and that's where you want it (cause that's where specs say it should* be, regardless of what they say a "universal carb" [without us in mind] was build for), with idle circuits barely open... and deceleration causes you to stall, you might need to bolt this part (11-4) on to prevent the throttle from closing too quickly:

(Clickity-click for larger image)


---There's many* factors when it comes to the carb not* being designed for our trucks. Your 266 is the rarest SV8, so don't count on them to know. Your best bet is to buy some books on Holley 2300s and learn from them, then apply that knowledge to your rebuilding/tuning. I'd start with older books, from 1965-1976.

---Then another possibility is that you need an anti-pullover Accelerator Pump Discharge Nozzle (AKA "squirter"), which will prevent the fuel from siphoning when you decelerate. #25 (121-225) would be lowest, #28 (121-228) might be more suitable and 32 (121-232) would be highest (in our application [266/304] of smaller SV8s) for this part. While not too normal an issue, almost mythological, it is always possible for an engine with excellent aspiration, you have a 266, so it changes a lot of "theory" into "dunno" cause not many have played with the older groups to know*. That would be out of many peoples' libraries/databases/memory banks because it was originally a 290cfm carb... "wus dat?".

---Wrong PCV Valve? Flame Arrestor not present and/or blocked off by a second PCV Valve/plug? What are your vacuum readings at idle?

---I know Holley doesn't have an alcohol-rated Power Valve, so what's the odds that it's got a pin-hole in it? Turn your idle mixture screws in all the way, 1/2 turn each until they both gently* seat and if the truck hasn't stalled out, by the time you get both seated, expect the power valve to be damaged by eGas. Then look toward BG, QFT or AED for one that is alcohol approved.

---Did they even give you a GFLT Accelerator Pump Diaphragm with the "new" carb? It would be green-blue sandwiched between two layers of black gasket.

---I think you have a long way to go with a carb that is not correct for IH and with a little know-how regarding the internal parts, you can have it running right, rather than what "seems* to be right"... or "as good as it gets".

There now. So much easier to digest minus the superfluous and non-pertinent drivel.

[Dave Peters]

Children,children. Let's get some more info on what was going on when this trouble evidenced itself. As this appears to be happening in Texas, and as we don't know at what time of year it was misbehaving, how about getting some history on this thing? Weather has something to do with it, I'm pretty sure.

[taltyman]

Ok, just so all know. I bought this from someone in Texas who had it about a year to putz around a lake. This guy also has a home in AZ and that's where he bought the Scout. The person he bought it from did all the rebuilding. There was no knowledge transfer between the 2 people on what was done. However when I bought it the PO provided a couple of boxes of original equipment that had been replaced. However a carb was not among them so I'm not sure if it is the original carb or not. I left it at my mechanics place yesterday to see what he can find as well as swapping out the fuel pump. So I can't take a picture for now.

Now on the symptoms again. My other truck was broke down so I took the Scout to work for 3 straight days. Every day was similar temp but the 1st day was probably the warmest in the mid 60s. The trip each way is 17 miles with about 12 miles on interstate. So day one to work, no problems. Day one trip home and I have problems when I exit the hwy. I limp it home and the next 2 days I have no issues.

Similarly this summer I took it on long hwy drives multiple times. Summer temps at 100 or so. These jaunts were 70-100 miles on the hwy before slowing down. About 1/5 of the time I would have problems. It's so irritating when it happens because it takes several minutes to restart and then it still is herky jerky for a while.

I'll report back when I get it back from the shop. Supposedly they hired a mechanic who understands old vehicles. We'll see.

I did a vacuum leak check with the only equipment I have (my hands), by removing the air cleaner and covering the intake with my hand to see if it died immediately or tried to keep running.

[scoutboy74]

Thank you for the supplemental. Too bad pics aren't a possibility. Intermittent issues are usually the most vexing to diagnose and repair. Successful cyber-diagnosis almost always depends on knowing what specific components are in play. Without that basic data, about all anyone can do is lob spitballs at the situation. Perhaps a lucky few hit the mark, but most will not.

[Dave Peters]

Since the trouble seems to happen with relatively warm temps, I ask whether the gasket between the carb and the intake manifold is the type that acts as a heat sink to lower the heat transfer to the carb. If you're doing high speed driving on freeways the heat can build without realizing it, so it seems the problem is vapour lock. Start there.

[Thomas]

---I throw out as many possibilities as I can think of, cause I don't know when I'll be around, and what little bandwidth it takes to type is better than people waiting for answers to "what do I check next?". I can also remember most of what I've learned & have the ability to think on my own. Now that I am through with the introduction, may I offer my apologies, taltyman if it is ever overwhelming... relevance comes with understanding and deciding what's applicable from the possibilities is up to you* as the one who inquired.

Originally Posted by taltyman

... I did a vacuum leak check with the only equipment I have (my hands), by removing the air cleaner and covering the intake with my hand to see if it died immediately or tried to keep running...

---On that note, for future reference, an aerosol can sprayed (I use hair spray) with contents having a low flash point, can be used to find vacuum leaks while the engine is running. RPMs would change if you find a leak. Just stay away from hot & electrical areas like exhaust manifolds & alternator so you don't start a fire. A cool engine works well enough most times. Spray around the base of the carb (paying special attention to the center of the front and back [where 90%+ of the cracks form from over-tightening mounting bolts] of the Throttle Plate, along intake runners, under the intake manifold and around mounting bolts, along vacuum lines (which should be replaced every 5 years) and thermostatic switches like the low/high temp switches. PVC valve must be clean and Flame Arrestor must be clean as well as present in the valve cover for proper PCV.

---If original, your carb should be a 1710... which rarely survived the journey to this day & age due to abuse by DIYers. Whatever you do, don't let anyone talk you into sending that in to be "refreshed" or as a core. That carb will prove to be invaluable and no matter what kit for older (non-44) 2300s you purchase to rebuild it, there's no "special" parts/gaskets that you will be seeking other than the Base Plate Gasket I mentioned in my first reply. You can rebuild it yourself with little common sense and good instruction and you stand no chance of being ripped off.

---Here's where you will find key info on a 2300/modular carb.

(Clickity-click for larger image)



---In the OEM world, there will be a List#, an OEM P/N & a Date Code. List# will say "List" xxxx(± -xxx-xxx) OEM P/N will be xxxxxx-xxx and date code would be xxx or xxxx.

---If you decide rebuilding of the carb is necessary, please do not be discouraged from asking what parts besides the actual kit should be used. We are in an era where ethanol gasoline damages components and while Holley isn't 100% alcohol-approved with their parts, some are and other companies do have parts that they don't yet make. You will be tossing the greater portion of any 2300 kit to the side and ordering special parts to complete the rebuild if you want the rebuild to last without issue. Some parts can be found here in the beginning of my entry to the Useful Part Number List thread. Just search for the keyword Alcohol (as well as Reusable) in that post (and ignore the 0.150" [Needle & Seat] Fuel Inlet Needle). The list of alcohol-rated parts I have had since 1999/2000 when I began the change-over on my system. A lot of those parts can be ordered from reputable ebay sellers at a fraction of what the big names want and some of t hose sellers even have their own performance shops you can order from as well. I'd like to think that in ten more years Holley will catch up, but they have a lot of governmental pressure as well as supply/demand to think of, so I don't hold my breath. Gotta fend for yourself.

---Let us know what List# and I'm sure we can give you a P/N for a rebuild kit as well as list of "special" parts. If the mechanic has already begun and that request is too late, no biggie. Maybe he will be wise enough to stamp the Main Body Gasket out of something like Buna!!! Doing that, you will never need to buy another kit, just stamp a few gaskets in case one tears while rebuilding and buy a new Needle & Seat, alcohol-approved Power Valve & Accelerator Pump Diaphragm.

---Don't want to spend the extra money? Consider: If the parts in the carb like the Power Valve match OEM, they won't be in a kit. That should be a 4.5-6.0 and the kit will come with a 7.5. You have to buy the correct ones anyway, so paying $3-$7 more for each alcohol approved makes sense. The Needle & Seat should be a 0.097" for the 266/304 and the kit will come with a 0.110", so you'll want to buy a matching there as well. The Fuel Float if not brass won't live much longer, so $4.99 for that is also logical. The carb will have to have the Fuel Bowl dropped at least* every 2 years to clean out debris, so reusable Metering Plate & Bowl Gaskets are wise... unless you want to buy another* $30+ kit just for those two gaskets. Rebuild for 1-2 years or rebuild for 5+ years. Your* choice.

---All removable parts will have part numbers stamped into them too, so don't just discard your old stuff and use the new trusting the kit's contents. Throw away that info and you'll be needing the correct* (pretty much era specific due to amendments) print of the Holley Ill. & Specs manual or someone who "doesn't know" to relay the info when it's too late; If they're not pushing up daisies... lol.

---Vapor lock, float/fuel level & condensation due to change in temps are excellent suggestions as well.

[TheScoutMaster]

I would can the diaphram fuel pump, and go with an electric inline and fuel regulator - all at Autozone for like $30.00...