IH PARTS AMERICA
Click Here!

Go Back   IH PARTS AMERICA > Tech Forums > Carb Tech
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read Photo Gallery IH Store Home

Reply
 
Thread Tools Display Modes
Old 12-23-2018, 09:38 PM   #1
chevyman
Junior Member
 
Join Date: Dec 2018
Member Number: 9543
Posts: 11
Default holley 2300 rich

I've been working on a list # 4574-001 came in on a scout in non-running condition. Usual ran when parked situation. I bought the carbs unlimited kit after my local NAPA told me their rebuild kit is unobtanium, and rebuilt like any holley. Runs but rich as all get out at idle. It had no fuel bowl vent plastic piece, and one of the idle adjust screws came out in two pieces, so I replaced with a very similar (same) needle. Upon startup it reeks of unburned fuel. I can adjust the idle mix screws in the base plate all the way in and not kill it. I adjusted float level to where I would normally put it, just bellow the threads. It wont idle until I pull the choke out just ever so slightly then it idles with a hunting. I took it back off and remembered that I have reused to orange umbrella check valve but it seems good. The idle screws have been everywhere from closed to 2.5 turns out and doesn't seem to make a difference. I can blow air through the primary jet circuits in the metering valve on the bench. Wondering what you guys would suggest next. Its got a wicked exhaust leak behind the y-pipe so it makes adjustments in the shop a bastard. Other than the idle and rich mix it runs great. makes 14-16 inches vacuum at idle but around 800-1000 rpm.
chevyman is offline   Reply With Quote
Old 12-23-2018, 09:47 PM   #2
FDChappie
Senior Member
 
FDChappie's Avatar
 
Join Date: Aug 2011
Member Number: 3742
Location: Northern New California
Posts: 1,580
Default Re: holley 2300 rich

Bad power valve?
__________________
1974 Scout II 345 T-19
1971 Travelette 392 T-36
1972 Loadstar 1700 dump truck 345 T-35
FDChappie is offline   Reply With Quote
Old 12-24-2018, 05:10 AM   #3
1975IH200
Senior Member
 
1975IH200's Avatar
 
Join Date: Dec 2008
Member Number: 731
Location: 3rd to last cave on the right
Posts: 559
Default Re: holley 2300 rich

Idle mix screws are just that. Idle mixture adjustment screws. They are only in use during idle. Your RPM of 800-1000 RPM is too high for them to have an effect. Get the engine idle down to 600-650, then adjust idle mix screws. Sounds like you have a vacuum leak. Also, be sure the ignition system is in tip-top shape before working on carb.
Plus: clean fuel and clean fuel filter.
What is the history of the vehicle and engine???
__________________

My Junk --> 1975 "200HD" AWD Truck
My Cave location --> Western North Carolina
1975IH200 is offline   Reply With Quote
Old 12-24-2018, 05:40 AM   #4
chevyman
Junior Member
 
Join Date: Dec 2018
Member Number: 9543
Posts: 11
Default Re: holley 2300 rich

Power valve was new. I'll check it today. Two new filters in line from tank. I'm running a holley electric fuel pump under the truck as the old sediment bowl style pump gave up the ghost with all the sludge formerly in it. I don't hear any vacuum leaks but I can start by plugging all ports other than advance. Had found one hose under dash unhooked, now plugged.
chevyman is offline   Reply With Quote
Old 12-24-2018, 05:43 AM   #5
chevyman
Junior Member
 
Join Date: Dec 2018
Member Number: 9543
Posts: 11
Default Re: holley 2300 rich

Truck has sat in a friend's shop for a few years. He said he bought it, drove it around the block, then parked it. Anything that touches fuel after tank is new or the carb.
chevyman is offline   Reply With Quote
Old 12-24-2018, 09:29 AM   #6
chevyman
Junior Member
 
Join Date: Dec 2018
Member Number: 9543
Posts: 11
Default Re: holley 2300 rich

Tested the power valve with a vacuum pump. It works as it should. The old one was stamped 13 as is this one. Seems way too high a number. I checked jet sizes, 51 in each. set the mixture screws in and backed them out 1/2 turn. it looks like the fast idle screw that sits against the choke lever was way too far in so I backed it out to where its not quite touching at no choke position and will adjust from there. Same with idle speed screw, not quite touching. going to set idle first once battery charges. Somebody stayed up too late working on it and left the damn key on.....
thanks, will update as I go.
In good news the master cylinder I bought from here works with pushrod works awesome and the brakes are doing their job!
chevyman is offline   Reply With Quote
Old 12-24-2018, 10:28 AM   #7
Scoutboy74
Moderator
 
Scoutboy74's Avatar
 
Join Date: Apr 2008
Member Number: 453
Location: Daze Crick, Jefferson
Posts: 4,076
Default Re: holley 2300 rich

That idle vacuum even at a slightly high idle speed is pretty low, unless the cam is aftermarket and/or you are at high elevation. These engines in stock trim typical pull high teens to low 20's hg at idle when all is well.
Do you have a regulator upstream from the carb fuel inlet? The factory mechanical pumps were calibrated to delivery between and 5 and 7 psi. An electric pump is capable of delivering well north of that figure unless regulated. Too much pressure can be problematic for a Holley carb.
__________________
Favorite hobby...Driving Salma Hayek in my Scout

Coal Trickle - '99 Dodge Ram SLT 2500 Q-Cab SWB 4x4 - 5.9L 24V CTD/NV4500/8800# GVWR/12K# winch
Hooty - '74 SII 4x4 - 392/TF727/D20/3.73 D44's/Spartan FA/Krac-lok RA/RC 4" SUA/34x11.5 TSLs/33g Fuel/8K# winch
Lemuel - '73 1210 Reg Cab 4x4 Camper Special - 304/TF727/NP205/4.09 FA25 & 4.10 RA16 - "Pull Lemuel, pull!"
Mongo - '71 1210 Reg Cab 2WD - 345/TF727/4.10 RA17 - "Mongo love candy! Duh, huh, huh!"
Scoutboy74 is offline   Reply With Quote
Old 12-24-2018, 10:47 AM   #8
chevyman
Junior Member
 
Join Date: Dec 2018
Member Number: 9543
Posts: 11
Default Re: holley 2300 rich

no regulator, my cheap HF fuel gauge read about 4 psi on the pump. Im in wisconsin so no high altititude.
I'm not ruling out the worn, rings or valves just yet, trying to get the darn thing to idle o.k. Ran great yesterday just rich.....
I'll most likely do a compression test in the near future.
chevyman is offline   Reply With Quote
Old 12-24-2018, 12:29 PM   #9
Scoutboy74
Moderator
 
Scoutboy74's Avatar
 
Join Date: Apr 2008
Member Number: 453
Location: Daze Crick, Jefferson
Posts: 4,076
Default Re: holley 2300 rich

Hopefully you didn't roast the points and/or coil by leaving power supplied to them that long with engine stopped. I'd spritz carb clean around any surface where a vac leak might be present, making sure none can enter the top of the carb, to see if engine speed changes momentarily.
__________________
Favorite hobby...Driving Salma Hayek in my Scout

Coal Trickle - '99 Dodge Ram SLT 2500 Q-Cab SWB 4x4 - 5.9L 24V CTD/NV4500/8800# GVWR/12K# winch
Hooty - '74 SII 4x4 - 392/TF727/D20/3.73 D44's/Spartan FA/Krac-lok RA/RC 4" SUA/34x11.5 TSLs/33g Fuel/8K# winch
Lemuel - '73 1210 Reg Cab 4x4 Camper Special - 304/TF727/NP205/4.09 FA25 & 4.10 RA16 - "Pull Lemuel, pull!"
Mongo - '71 1210 Reg Cab 2WD - 345/TF727/4.10 RA17 - "Mongo love candy! Duh, huh, huh!"
Scoutboy74 is offline   Reply With Quote
Old 12-24-2018, 12:52 PM   #10
chevyman
Junior Member
 
Join Date: Dec 2018
Member Number: 9543
Posts: 11
Default Re: holley 2300 rich

Checked and gapped all plugs, and few had suspect connections at the wires, set carb back to base and after it warms up I can get it to idle without choke and all by itself. adjusted the mixture screws according to vacuum gauge and get about 15 in. Smells a little rich, but plugs look o.k. and it sure needs exhaust before I go any further. (hate to burn an exhaust valve) I'm calling this one fixed for now. Don't have a tach, but it sounds o.k. and slips in to gear fine. Thanks for all your help I've really been mining this forum for the past 48 hours.
chevyman is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 10:50 PM.