WTF?!

[JPD685]

Welll to start off, I have a 1979 International Scout II with a 304 v8. 2 barrel Holley 1904 carb I believe...

It was running perfectly fine last night and all yesterday( I have been dd this thing for 2-3 months now with no problems...). I start it up this morning starting to head to work, and it was running a little rough but it was still driveable.... I start it up on my lunch break and its running really rough( so rough I could hardly move the truck...), so ilet it warm up a bit and is still running very rough, take it for a little drive and its sputtering and backfiring alot.... Running very rough.... But it was running fine last night? :s still has lots of gas deffinatly getting spark cause its starting but just running really shitty... Really confused here and help appreciated!

 

[Scoutboy74]

Your carb wouldn't be a 1904 model. That's a single barrel carb found commonly on ihc 4 cylinder engines. If all original, yours would be a 2210, but its also possible that a 2300 has been swapped on at some point. We'll need to know for sure which model you have, so please post up some good closeups of the carb with air filter canister removed as well as some all inclusive engine bay shots from both sides.

The symptoms you've described could be caused by a number of things including, but not limited too...plugged fuel filter, contaminated fuel supply, failing electronic ignition module, failing coil, carb in need of refurbishment, vacuum leak, stuck or inoperable choke mechanism...and the list goes on. We don't have enough specifics to begin ruling anything out just yet.

The ethanol blended fuels that most of us are forced to consume now are murder on carbs, especially ones that have not been properly serviced in the last two years. Its not realistic to expect a gummed up carb that's been out of service for x amount of time to perform flawlessly by doing nothing more than adding fresh alkyfuel to the equation. Again, I don't know if that's the scenario here. We need more background about this rig. Overall condition, what's been done to it, so on and so forth going back further than just two or three months time.

 

[JPD685]

Well I know for sure its not a 2300....carb deffinatly looks like a 2210c or atleast 2200 series..... It originally came (when I got it) with a streeet Holley 2300.... Sucked for offroading.... Bought a part Scout that ran and drove but was rusty as shit, carb was perfect.... It has a red autolite tag on it and says Holley but I dont see any numbers or anything like that........ It looks like its in new shape and the power pumps seem to be shooting a good strong flow with no stoppage.....

I have an aftermarket tachometer on it that I installed about 2 months ago... It is seeming to flucuate quite a bit and jumping aroind so I was kinda thinking maybe the coil (ex; when rev'd at 2000rpm, the tach will jump to 4000 every once and a while even when im holding it at a steady pace...). It has a nice msd coil on it that looks almost new so im not sure... I have only had this truck for about 4 months at the most now and the only thing that I have done is clean the engine, and put this new to me carb on this truck, as well as putting a aftermarket tach. I have a new fuel filter but have not put it in. Ill take some pics of the carb after work...

I pulled out the fuel tank and pump to hook up new fuel lines about 2 months ago as well and the tank looked really clean so unless I have gotten water in it somehow? It wasnt at all rusty nothing in the bottom of the tank, looked very clean.... I started it up not to long ago, it seemed to run a little better, hopefully ill be able to make it home.... Lol

 

[Scoutboy74]

Sounds like the 2300 variant that was on the engine initially was a list 4412, which is definitely not suitable for your application. Those are calibrated way too fat across the board. The other aftermarket variant of the 2300 is a list 0-7448, which has been proven time and again to work very well with these engines. But that's a moot point at this stage since we're not dealing with either version.

We still need to make positive id on this sucker. From your description it could even be a motorcraft/autolite 2100, which is slightly similar, but far from identical to a Holley 2210. We also need to make sure that the choke mechanism is functional - yes, even in summertime. It needs to close up when the engine is cold and open all the way without binding as the engine reaches operating temperature. Outside ambient air temp has little to do with cold starts inside a heavy, cast iron block.

Also, external carb appearance doesn't necessarily correlate to internal condition. There are tiny passages inside the "brain" of the carb that are quite susceptible to corrosion and blockage. They can't be seen until the carb is completely disassembled. Your carb May be perfectly fine inside. I'm simply making a point. Be cautious about judging a book by its cover. Doesn't matter how clean your tank appeared to be. You should be running two fuel filters at all times. One on the tank side of the fuel pump and one on the carb side.

We also need to make positive id on your distributor. We know what it should be for m/y '79, but what it came with and what it has now can often be two very different things, with your carb as exhibit a.

So, here I am beating a dead horse and I make no apology for doing so. If you have access to a decent digital camera, please snap the requested pics and post them once you have a chance during the daytime. Think of your engine bay as a certain part of the female anatomy. Once I've seen one "pair"...I basically wanna see 'em all. It does me no good to look at pics of someone else's '79. It ain't yours. We just might see something really obvious that is out of whack that could have a major bearing on your engine performance.

 

[JPD685]

Here are some pics, let me know what you think. Btw it ran fine on the way home, sputtered a little bit but hardly noticeable and only once and a while. Been driving it tonight and having no problems, somewhat sputters but driving none the less. Yes the list on the 2300 was 4412.... I had another one that was had 7448 on it, but it also had 4412 lol :s but thats here nor their cause I dont have it anymore.

 

[Scoutboy74]

Thanks. The carb is a Holley 22xx. One picture clearly shows evidence of raw fuel seepage from the fuel bowl due to gasket failure. Overall I'd have to disagree with your assessment that its in like new condition. Looks to me like a candidate for a rebuild.

I see quite a few vacuum lines capped off. Any one of which has the potential for creating a vacuum leak. Your throttle return spring routing looks kinda dicey. Not that its contributing to your performance issues, but as a general safety concern, those could use some improvement.

This type of carb incorporates a divorced choke mechanism that is pulled off via a vacuum diaphragm. Have you watched the choke mechanism during a cold start to see that it functions properly?

You've also got an egr valve which is the brass-looking object behind the carb. These are failure prone. Is there still a vacuum line connected to it?

I can't tell from the pics what type of distributor you have. Would you be able to supply a couple that show it with cap removed and the terminal connections of the ignition coil?

Don't lose heart. This is a fairly typical example of a total po abortion. Now you're the guy tasked with trying to make it right again. It can be done, but there's no one quick and easy fix. Clearly there are a number of items that need attention. Just wait 'til mayben weighs in. He'll probably spot some additional items that I missed.

 

[JPD685]

As for that gasket that looks like it leaked, I didnt notice that till I was taking the pictures. So yes, its deffinatly going to need to come apart be cleaned and rebuilt... Yes the I know the throttle springs are a little funny, I only had one on there and didnt like the tension of the gas pedal and didnt have any other springs that were stronger so I put 2 weaker ones.... It was like new when I put it on 2 months ago and there deffinatly was not leakage in the gaskets.

No I have not looked at the choke, but it seems to operate great.... I start it up, rev's at 1000 rpm and slowly goes up as it gets warmer, I give the pedal a quick jolt and it drops down to idle.
I have noticed when it is cold in the morning, it wants to almost stall if you are going slow and give it a little to much gas when first starting to move. Until it is warm then its operating perfect. (well was)

there is no vacuuum line to the egr and it is capped off. I honstly dont know where lots of those lines go and most were capped off when I got the carb.

Ill try to get pics later today of it but im in the middle of re-sealing a 302 currently.

 

[Scoutboy74]

Sounds like your choke is at least somewhat functional. That's good. Have you noticed heavy black smoke from the exhaust and smells of unburned fuel out the exhaust when the engine is idling? If so, here's something to try. Those carbs are notorious for blowing power valves, especially after some good pops back through the carb. Warm it up to where it will idle unassisted. Take a screwdriver and slowly turn the idle mixture screws in until gently seated. If the power valve is blown, this will have no effect on idle quality. If the valve is still functional, the engine will fall on its face until it stalls out. There are two different types of power valves used with these carbs. Getting the correct one is essential.

A normally functioning power valve provides temporary fuel enrichment under load in response to falling vacuum signal. A failed pv sticks open, providing constant enrichment even when not needed. Naturally, this hurts fuel economy and fouls spark plugs. Pv's are repair items included in rebuild kits. Before you attempt any service on this carb, I highly recommend you read through the stickied 22xx thread in the carb tech sub-forum. It contains exploded views of the carb and discusses part numbers for the appropriate rebuild kit.

As for the vacuum hose routing, is it correct to assume this rig is no longer subject to periodic smog certification where you live? If so, much of that stuff can be "optimized" for "offroad use", but it needs to be done properly. The original smog components were meant to function as a cohesive system. A partial or half-assed disabling of that system often leads to performance issues. I know you didn't do it, but that's where you're at now.

 

[JPD685]

I will deffinatly try that. Not when idling but when I stomp on it, a few seconds after I let off I can deffinatly smell gas.

Where I live we do not have aircare for insurance so thats no problem. Well where would I find the correct procedure to do this properly?