345 ran fine now light popping and rough idle

L

lastclark84

New member
I have a 345 that has new pet ing, holly 2 barrel carb, coil, plugs wires. I have run this motor just moving it around and letting it sit and warm up since I have installed these parts and it has always ran perfect and started very easy hot or cold. I took it down the road for the first time and drove it for about an hour. I noticed it was running rough so I parked. Now it is rough on idle and has a light popping , cracking sound through the exhaust. I put a new coil since then and thats it. Please help, thanks a lot
 
lastclark84 said:
I have a 345 that has new pet ing, holly 2 barrel carb, coil, plugs wires. I have run this motor just moving it around and letting it sit and warm up since I have installed these parts and it has always ran perfect and started very easy hot or cold. I took it down the road for the first time and drove it for about an hour. I noticed it was running rough so I parked. Now it is rough on idle and has a light popping , cracking sound through the exhaust. I put a new coil since then and thats it. Please help, thanks a lot
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Need more info here!

What distributor is the pertronix installed in? How is it wired to the coil?

What is the list number on the 2300 carb, what's the story on it's condition?

Can you install a shop-type vacuum gauge and give me some readings at idle?
 
It is a holly distributer.it is wired as the stock points were. I followed the instructions that came with the ignition. The carb is a new 0-4412c. The truck has bad valve guide seals and puffes a little smoke but has never fouled plugs. After it started missing I checked them and some look fouled but not soaked with oil more like they just didn't have enough spark.
 
A Holley list 4412 is totally the wrong 2300 carb for that engine. Not only is it simply jetted way fat, the metering circuits are way too "Rich". I've spent hours and days trying to make 'em work correctly, I can't do it without a large assortment of alternative metering blocks to try, it's simply not worth the effort. If you simply jet it down, the metering block cannot cope with that and it will only get worse.

We've posted about this subject in many threads in the carb tech sub-forum. Search key word "4412".

The sv engines don't have true valve stem seals, only a crude form of oil "deflector". It is entirely within their normal character to blow smoke at start-up, that really means nothing if the smoke subsides after 30 seconds or so.

I'm suggesting that your plugs are majorly "fuel fouled" due to the extremely Rich mixture that carburetor is providing. Install new plugs, drive it awhile (and no way it's running like it's should be!), and it'll foul those plugs randomly also.
 
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So you think I should get a different carb? Also back to the smoke, it will puff out a little after you rev. The engine sat for a while. I have read that an oil drain gets clogged and could cause that?
 
I have the same carb on my 304. I just ordered the correct carb from IHOnly. Been through the same issues. Mayben's advice is the best advice, ditch the 500cfm "race" carb and install the correct list 350cfm carb for your motor. IHOnly will even jet it for your elevation, engine setup, etc. And install an electric choke kit. Even if you change the plugs every week you'll be sniffing gas and spitting fluid out of the tailpipe.:sad:
 
I'm going to do craigslist/e-bay. They are popular carb for dirt track racing etc. You need a list 7448 Holley or equivalent application. There are many avenues to find an affordable carb, remans, craigslist, e-bay,etc. I'm gonna suggest IHOnly because they will set it up correctly and ship it to you ready to install. You pay more you get more. But all the symptoms you posted are exactly what that carb is doing in my Scout (to be fixed next week). When you rev the motor you are getting white smoke (un-burned fuel), the tailpipe is dripping (unburned fuel), you can't run the truck in a closed space cause the inburned fuel smell is killing you. Post a request in the parts needed thread. Might be someone has one they are willing to part with, sell cheaply. This is a great community and from spending alot of time on here myself I think I can safely say that someone/s May be able to help you out.
 
Man that is dead on! That is exactly what mine does. It will stink up the house if I run it under the car port for a minute. The plugs did smell like gas. Thank you both for all the support. I will just have to get the right one and sell this one. It is in perfect condition so that shouldn't be a problem. Are the re manufactured carbs any good? That's probably what I will have to go with. Also what is a fair asking price for my carb? Like I said its in perfect condition and I still have the box its only a couple of months old.
 
Okay that will work. Thanks again both of you for the helpful answers. I will get the right carb on here and should be fine.
 
I might have one you can have for just the shipping charge. Had it on a 345, put a 392 in with 4 barrell, im sure it needs a rebuild.......let me go check the numbers on it.

R6620 2a
441192-c92
2614

on the bottom of the fuel bowl is: 6r4420b

if this is what you need let me know
 
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Good deal and good luck. If it makes you feel any better my wife is using my Scout as a daily driver. Once you get educated and understand the vehicle you should be able to get it running well all the time.
 
This saga regarding the Holley 2300/list 4412 is one I encounter constantly! Most folks simply look at the "carb selector" crap on the Holley website, or jegs, or summit, or,.... And those "aids" are totally irrelevant to any ihc-produced engine! We're talking truck engines here and prime movers used in stationary applications and buses! These are not and never will be in the same league "performance-wise" as the typical fe Ford, big block chev, "b" block chrysler, etc. They only thing they have in common is the fact they all burn alotta gasoline!

That 4412 as has been described is a particularly popular "class" mixer used around the world for circle track racing and other forms of motorsport where everyone has to run the same carb. And yes, they can certainly be used on a street-driven engine in the horsepower range of 300+. But for an ihc 2v manifold, they don't fit properly, can't be calibrated properly, and are just plain wrong!

I know of two folks who "claim" theirs work perfectly on a 345...., one is a guy who is totally full of shit all the time and I wouldn't trust anything he blows about...the other guy claims that Holley sent him that "special" metering block that no else in the world has and was custom cnc-machined just for him at no charge by the Holley custom shop. Only he can't produce pics, can't produce any information, and I know is also fullashit!

I have four really nice 4412 carbs on the shelf right now. All ready to go. In the spring, I'll put 'em up on the regional craigslists and the circle track dudes will snap 'em right up. Then they send 'em off to have "cheaterized" for another $300 or so.

We do have one 2300 right now that needs to be refurbished and would be suitable for mounting an electric choke. This particular design series core is extremely difficult to come by that is not broken or rotted internally due to abuse. And as soon as I get one ready, it's snapped up. If I come up with anything that is a "good deal" I'll certainly let ya know.
 
lastclark84 said:
so you think I should get a different carb? Also back to the smoke, it will puff out a little after you rev. The engine sat for a while. I have read that an oil drain gets clogged and could cause that?
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While any engine could have semi-blocked oil return ports in the heads, that is not an issue with ihc engines whatsoever if they were "maintained", one more typical urban ihc myth! Problem is...most of these engines have been sitting non-rotated for years and not maintained before that! They are badly sludged internally with an oil pump float nearly totally restricted and cam bearings trashed due to lack of proper maintenance and lubrication.

It's dam simple to pull the valve covers and look at the oil drains at the lower rear corner of each head. That needs to be done anytime these engines have set for a period of time so that rocker assembly lubrication can be observed before spending cash on other work.

We've gone to extraordinary lengths here at ihon to develop and publish all the information needed to diagnose any I-4 or sv engine lubrication issue, all the information is posted in stickys at the top of the gas engine tech sub-forum.

And nearly every member thread posted in that same sub-forum has to do with "noise" and engine problem diagnosis and what to do to correct issues.
 
Mike, according to Jeff you went down and gave a class on setting up a Holley carb. When I talked to him wed when I was ordering some more parts he said he would be doing the setup. Should I be concerned? I mean I have seen all the vehicles he has done...but:idea:...I'm sure you edumicated him real good. Have a good thanksgiving and once again thanks.
 
scoutpappa said:
Mike, according to Jeff you went down and gave a class on setting up a Holley carb. When I talked to him wed when I was ordering some more parts he said he would be doing the setup. Should I be concerned? I mean I have seen all the vehicles he has done...but:idea:...I'm sure you edumicated him real good. Have a good thanksgiving and once again thanks.
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Don't be concerned at all about the carb setups done at ihon hq!

It just doesn't make sense that when many of the components that go into our kits are in two locations, that we not expedite this deal. Therefore we can do the carb package setup (along with many other component assemblies from either location).

We have a standard "build sheet" in the ihon dbase now that gives the exact recipe. Some folks already have some of the items so it doesn't make sense that they get duplicates, so each one is done to order. And normally several additional parts are ordered from ihon at the same time so that the shipping May be consolidated.

All the boyz at ihon are top hands! They simply refuse to turn out anything that is not first class and customer service after the sale is always a priority. And we talk and email back and forth all day long about "stuff"! If you have any questions or need other assistance when setting up the carb you ring my bell!

I know this rig has replaced the Ford for your wife, and it better start cold just like that efi Ford also! We're gonna keep her happy and she'll soon realize yawl made totally the right decision about going with old iron!
 
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Thanks guys for the help! Building this 67 Scout has been a long journey and this carb issue is the last little bug I have to work out. I posted my carb for sale and I will be buying a 7448 and get this gas fumed race carb of of my IH! As soon as I get a chance I will post some pics of my build. Thanks again everone
 
Appreciate that Mike. I know Jeff and co. Will treat me right. It was more of a jest because Jeff is so humble when discussing the carb build. He definately let me know who told him how to do it. Should have phrased it a little differently. Just to make sure that it wasn't taken wrong, I want everyone to know I have absolute confidence in IHOnly and all associates. That is the reason I order my parts (critical) from the experts. Wouldn't have had the confidence to make the swap without the great customer support from IHOnly and the great information provided on this tech forum.:ihih:
 
scoutpappa said:
appreciate that Mike. I know Jeff and co. Will treat me right. It was more of a jest because Jeff is so humble when discussing the carb build. He definately let me know who told him how to do it. Should have phrased it a little differently. Just to make sure that it wasn't taken wrong, I want everyone to know I have absolute confidence in IHOnly and all associates. That is the reason I order my parts (critical) from the experts. Wouldn't have had the confidence to make the swap without the great customer support from IHOnly and the great information provided on this tech forum.:ihih:
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A little insight on the level of experience with ihc junkiron from the boss' side!....

Of all the Ismail kids, three of the brothers are world-class experts in screwin' with this stuff. Their pop made sure of that since he wouldn't allow 'em to suk onna bottle or change their shorts until they could crawl under any one of his pieces of IH rolling stock and change oil without using a creeper. This is for the most part all that Isa, Mike, and Jeff have ever done with some breaks to earn cash for family use doing whatever they had to do (legally!!). The two other siblings were much smarter though and went into the computer world so they can stay clean, retain their hearing and sight, and not have to change pop's oil on a continuous basis.

So yeah, any of 'em can dam shore jet a Holley!

Kathy and I certainly are privileged to consider ourselves part of the Ismail family unit! And pop Ismail can still kick my azz too when he needs to!
 
What should the timing be set at for my 345 and im running autolite 303 plugs at 30 gap. Want to know I have everything set up right. I have a 0-7448 carb on the way.
 
Just thought I would let yall know I finally got the 7448 carb delivered. I put a fresh set of plugs, all new rubber hose going to the carb, fired it up and set the timing. Holly shit! It runs like its brand new. No horrible gas smell, fouled plugs, the gas peddle isn't so touchy, its perfect. Thanks a lot
 
lastclark84 said:
just thought I would let yall know I finally got the 7448 carb delivered. I put a fresh set of plugs, all new rubber hose going to the carb, fired it up and set the timing. Holly shit! It runs like its brand new. No horrible gas smell, fouled plugs, the gas peddle isn't so touchy, its perfect. Thanks a lot
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There ya go...another successful ending!!! (or is it a beginning?).

Ain't it amazing whatcha can learn by doing homework first? Now ya know why yore teachers all beat that into yore head??? We weren't so stoopid afterall???
 
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