- Thread starter
- #41
Thanks MoCoNative. Truck is running great now. Been checking my new clear filter for about a week now with no debris so I'm thinking you're right about the gunk being in the line. Thanks again for all the help guys!
Rebuilt carb problems at higher speeds.
- Thread starter calixto
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
- Joined
- Apr 14, 2004
- Threads
- 1,467
- Messages
- 36,650
- Location
- 818-953-9230
- Website
- www.marksoffroad.net
- Thread starter
- #43
This is the one you are referring to Mark? [SIZE=-1]057-40AR [/SIZE][SIZE=-1]SUPPORT BRKT, THROTTLE RTRN, REPRO, 10/69-2/73 [/SIZE][SIZE=-1]30.00 [/SIZE]
I definitely would like to pick one up if so. Jst to be sure, my carb is mid-74 not 73 if there is any difference in the design between that time.
Thanks again.
I definitely would like to pick one up if so. Jst to be sure, my carb is mid-74 not 73 if there is any difference in the design between that time.
Thanks again.
- Joined
- Apr 14, 2004
- Threads
- 1,467
- Messages
- 36,650
- Location
- 818-953-9230
- Website
- www.marksoffroad.net
Technically, not used on a 74. The real determining factor is if your 74 uses rod or cable linkage. 74 is SUPPOSED to have rod linkage. The bracket is NOT needed with cable linkage.
If your truck is running a cable, then chances are it IS the bracket you need.
Best
Mark A.
If your truck is running a cable, then chances are it IS the bracket you need.
Best
Mark A.
- Thread starter
- #45
So after two more instances of the carb clogging up we finally determined that the gunk was getting into the carb from the banjo bolt fitting. I guess there was some loose material in there when they fabbed it up. What a nightmare this has been but it finally seems solved. Thanks again for everyones input, it helped a lot. I just wanted to post this one last discovery on here in case someone else has this same issue and is having a hard time tracking down where something might be coming from.
- Joined
- Apr 14, 2004
- Threads
- 1,467
- Messages
- 36,650
- Location
- 818-953-9230
- Website
- www.marksoffroad.net
I noticed something else that needs addressed on your rig. I looked back through your photos to see how the fuel line is hooked up, and noticed your oil lines.
In post #10 you have a picture that shows your intake area. On the bracket that holds the oil filter, there are two lines that come off the back side. These actually carry the oil to and from the filter. They appear to just be rubber fuel line with hose clamps on them. It is common to have to replace the factory oil lines when headers are installed because they are too short to reach around the header. However, the factory lines have banjo fittings on the end and such to make a better conection, but more importantly they are reinforced line to deal with pressure and to give them strength. When installing a header the best alternative are stainless steel lines, that are longer. The header gets very hot, and can melt and or make brittle any rubber line near them. Many vendors sell new, longer stainless lines. You will need new banjo bolts and copper washers too, if you go that style. I have used some from MAF that did not use the factory style banjo, just screwed in on each end, also have a set now from Specter that match the factory lines with banjo fitting, but longer stainless.
Many moons ago, when my dad had my 40, the factory line burst on a very, very cold day, bout 20 below. Left him stranded, as the engine pumped all the oil out on the ground right there. Luckily he was only a mile from town. These are very important lines, and they appear to be insuficient on your engine. I also had issues with the header and my clutch hose getting too hot. Replaced it with stainless also.
In post #10 you have a picture that shows your intake area. On the bracket that holds the oil filter, there are two lines that come off the back side. These actually carry the oil to and from the filter. They appear to just be rubber fuel line with hose clamps on them. It is common to have to replace the factory oil lines when headers are installed because they are too short to reach around the header. However, the factory lines have banjo fittings on the end and such to make a better conection, but more importantly they are reinforced line to deal with pressure and to give them strength. When installing a header the best alternative are stainless steel lines, that are longer. The header gets very hot, and can melt and or make brittle any rubber line near them. Many vendors sell new, longer stainless lines. You will need new banjo bolts and copper washers too, if you go that style. I have used some from MAF that did not use the factory style banjo, just screwed in on each end, also have a set now from Specter that match the factory lines with banjo fitting, but longer stainless.
Many moons ago, when my dad had my 40, the factory line burst on a very, very cold day, bout 20 below. Left him stranded, as the engine pumped all the oil out on the ground right there. Luckily he was only a mile from town. These are very important lines, and they appear to be insuficient on your engine. I also had issues with the header and my clutch hose getting too hot. Replaced it with stainless also.
- Thread starter
- #49
Thanks for the heads up, I will replace the oil lines soon!
This is my fuel delivery set up and the banjo bolt my mechanic set up for it. Fuel return to the PCV valve is coming from the outlet on the carb base. He swears this is a good place for the fuel delivery and it has good flow into the carb there. Pics 1 and 2. you can see the delivery line going into the carb.
Got the truck back last night and everything seemed okay. I did notice a decent gas smell in my garage later in the evening after it had been back for a while. I wrote this off as residule gas smell from all the work that had been done on it. Gas smell didn't seem as bad this morning. This is a concern since I have the truck parked in my garage with my water heater.
Cut to this morning when I tried to fire it up and no go....the battery was pretty low and I didn't have much time to mess with it so I just left it until this afternoon when I had some more time. I tried to fire it up several times same thing, it just wouldn't catch. Tried it with the choke on, off and also pumping the gas and full gas no pump. Nothing. It's like it would get close to firing and not quite get there. Float bowl was at about the same height as in pic 3...jst slightly below the marking. Is this too low?
As my battery was getting really low and didn't want to jump it, I took the air cleaner off and sprayed some quick starter in the carb and the truck fired up. It seemed pretty rough and I couldn't let it drop to idle or it would die out. I ran it for about a 2 mins with the choke and no gas. Float bowl was no change. I continued trying to warm the car up for another couple mins with no choke and me pumping the gas, before I left. The engine was still pretty cold when I left and I had to jump back to revving the engine in neutral anytime I came to a stop. I drove it for a little while at normal temp and it seems to run pretty decently once warm and under gas. I don't have a problem at higher speeds like I was having before, that was solved a little while ago. It will drive 65+ no problem.
Once warmed up the truck could come to a neutral stop or even a long standing idle with a la couple little revs at the begining of going into a neutral stop. Even after the truck has warmed up and I am driving it some when I left off the gas but still in gear slowing down there is are a lot of popping noises. My old Rochester would do this some as well but not as bad. I do have a Flowmaster 40 on the exhaust so this sound might be getting magnified??? The engine also seems to cut out when going from slowing down into neutral or clutch in stop....it needs a couple revs to get it back to a good standing idle.
I am at a loss. I have the truck back at home and am going to watch the float bowl overnight(to see if it drains empty) and try to fire it up again tomorrow. My mechanic has been really helpful and has gone through the top end of the carb several times. I trust his knowledge, his business has been around a long time and he also specializes in carbs, tuning, older cars and hot rods, etc. He hasn't charged me but for the first time I came in and has sent a decent amount of time checking the thing out. I wish I could describe in detail all the things he has looked at or tried but I'm just not sure. Anything you can think of that might be causing any of these symptoms. Thanks guys...sorry for the long description.
This is my fuel delivery set up and the banjo bolt my mechanic set up for it. Fuel return to the PCV valve is coming from the outlet on the carb base. He swears this is a good place for the fuel delivery and it has good flow into the carb there. Pics 1 and 2. you can see the delivery line going into the carb.
Got the truck back last night and everything seemed okay. I did notice a decent gas smell in my garage later in the evening after it had been back for a while. I wrote this off as residule gas smell from all the work that had been done on it. Gas smell didn't seem as bad this morning. This is a concern since I have the truck parked in my garage with my water heater.
Cut to this morning when I tried to fire it up and no go....the battery was pretty low and I didn't have much time to mess with it so I just left it until this afternoon when I had some more time. I tried to fire it up several times same thing, it just wouldn't catch. Tried it with the choke on, off and also pumping the gas and full gas no pump. Nothing. It's like it would get close to firing and not quite get there. Float bowl was at about the same height as in pic 3...jst slightly below the marking. Is this too low?
As my battery was getting really low and didn't want to jump it, I took the air cleaner off and sprayed some quick starter in the carb and the truck fired up. It seemed pretty rough and I couldn't let it drop to idle or it would die out. I ran it for about a 2 mins with the choke and no gas. Float bowl was no change. I continued trying to warm the car up for another couple mins with no choke and me pumping the gas, before I left. The engine was still pretty cold when I left and I had to jump back to revving the engine in neutral anytime I came to a stop. I drove it for a little while at normal temp and it seems to run pretty decently once warm and under gas. I don't have a problem at higher speeds like I was having before, that was solved a little while ago. It will drive 65+ no problem.
Once warmed up the truck could come to a neutral stop or even a long standing idle with a la couple little revs at the begining of going into a neutral stop. Even after the truck has warmed up and I am driving it some when I left off the gas but still in gear slowing down there is are a lot of popping noises. My old Rochester would do this some as well but not as bad. I do have a Flowmaster 40 on the exhaust so this sound might be getting magnified??? The engine also seems to cut out when going from slowing down into neutral or clutch in stop....it needs a couple revs to get it back to a good standing idle.
I am at a loss. I have the truck back at home and am going to watch the float bowl overnight(to see if it drains empty) and try to fire it up again tomorrow. My mechanic has been really helpful and has gone through the top end of the carb several times. I trust his knowledge, his business has been around a long time and he also specializes in carbs, tuning, older cars and hot rods, etc. He hasn't charged me but for the first time I came in and has sent a decent amount of time checking the thing out. I wish I could describe in detail all the things he has looked at or tried but I'm just not sure. Anything you can think of that might be causing any of these symptoms. Thanks guys...sorry for the long description.
Last edited:
- Thread starter
- #50
Sorry one more thing. Jst checked the float window and it is drained, or empty, truck has been sitting about 2 hours. Where the heck could that even be going?......there are no visiable leaks or spots where it looks like gas might have run out between a gasket or something.
The fuel inlet is where you have the brass plug under the banjo fitting. I'm not sure what the port with the banjo fitting is on your carb, but it was capped or plugged at the factory. On later year carbs (3/73 and up), it is the fuel return, which has a restrictor in it to limit the fuel flow. Just looking at your pictures and comparing them to the pictures on the SOR site, it looks like you have a 3/73 carb, because it had the fuel return banjo fitting just like yours. Try using the proper fuel inlet and cap the banjo port and I bet your problem will go away.
It sounds like the fuel is either evaporating, siphoning or dripping into the intake.
It will take some time to start it as you need pump gas to fill up the bowl first. If there is fuel in the bowl, give it a couple of pumps, put the choke on and it should start right up. If the bowl is empty, drip a teaspoon of gas into the carb first and it should start right up.
The PCV valve is hooked up to manifold vacuum and has nothing to do with fuel return. The fuel return line was on later carbs to prevent vapor lock by keeping the fuel moving in the line.
It sounds like the fuel is either evaporating, siphoning or dripping into the intake.
It will take some time to start it as you need pump gas to fill up the bowl first. If there is fuel in the bowl, give it a couple of pumps, put the choke on and it should start right up. If the bowl is empty, drip a teaspoon of gas into the carb first and it should start right up.
The PCV valve is hooked up to manifold vacuum and has nothing to do with fuel return. The fuel return line was on later carbs to prevent vapor lock by keeping the fuel moving in the line.
Last edited:
cruiserbrett
GOLD Star
If you can, bring it by whereever we meet on the 25th and I can help with getting the fuel line routed properly.
Youre going to need some stuff from specter to make new hardlines from the fuel pump to carb...
specter:
028-11a compression nut (2)
028-08A-U correct fitting for carb fuel inlet. (2) if you have an old fuel pump you can use one off it
042-14 plug*
042-93 washer*
*these last two you might need to find from someone with a parts carb. or ask Mark A.
Napa:
a 5/16" steel hardline 51" long.
5/16" compression ferrules(or called olives)
i can bring the dremel and the tubing bender to make a correct fuel line. if you want to run the return(and have the plumbing on the vehicle), you dont need the 042-14/93. but you will need one more 028-11a
call me with questions.
-Brett
Youre going to need some stuff from specter to make new hardlines from the fuel pump to carb...
specter:
028-11a compression nut (2)
028-08A-U correct fitting for carb fuel inlet. (2) if you have an old fuel pump you can use one off it
042-14 plug*
042-93 washer*
*these last two you might need to find from someone with a parts carb. or ask Mark A.
Napa:
a 5/16" steel hardline 51" long.
5/16" compression ferrules(or called olives)
i can bring the dremel and the tubing bender to make a correct fuel line. if you want to run the return(and have the plumbing on the vehicle), you dont need the 042-14/93. but you will need one more 028-11a
call me with questions.
-Brett
- Thread starter
- #53
Thanks Brett! Was gonna call you anyway. I'll get all the necessary parts together.
Get with Brett and get the lines hooked up proper. That long run of black hose may be why you boiled all the gas out of the float bowl, it gets hot, vaporizes and pushes the fuel out of there. Also have him look at your oil lines and see what you need. I fear someone may have cross threaded bad nipples into the outlets of the oil filter housing. I'm not sure if they will accept regular pipe thread type items, or fuel line threads or what they require.
How cold is it where you are at. One reason for poor running when the engine is cold, is the headers. Sotck config, the exhaust manifold heats the intake manifold, as they are bolted together. This quickly, almost immediatly heats the intake for proper atomization of the fuel and air mixture as it passes through the intake runners into the engine. When I ran headers, I fought this constantly, but that was in temps from 40F to -20F, I doubt you are that cold, but it does make a difference.
Also, check your idle selenoid. It is located on the back side of the carb, has a black wire coming out of it. It is above the point where you throttle cable is attached. This must be hooked up to 12V igniton switched power. You should hear it click when you turn the key to on. This dictates the idle curcuit of the carb. It is easy, especially after messing around the carb to knock the small bullet connector loose. And or the wires run above head, out of the hole that the choke cable comes out of. The other wire there should be the wire for the water temp sensor in the head. Both of these wires get pretty brittle over time, and may break internally, or at the connection to the butt connector. I have had to add wire to both of mine because of bad connections and wire degradation.
How cold is it where you are at. One reason for poor running when the engine is cold, is the headers. Sotck config, the exhaust manifold heats the intake manifold, as they are bolted together. This quickly, almost immediatly heats the intake for proper atomization of the fuel and air mixture as it passes through the intake runners into the engine. When I ran headers, I fought this constantly, but that was in temps from 40F to -20F, I doubt you are that cold, but it does make a difference.
Also, check your idle selenoid. It is located on the back side of the carb, has a black wire coming out of it. It is above the point where you throttle cable is attached. This must be hooked up to 12V igniton switched power. You should hear it click when you turn the key to on. This dictates the idle curcuit of the carb. It is easy, especially after messing around the carb to knock the small bullet connector loose. And or the wires run above head, out of the hole that the choke cable comes out of. The other wire there should be the wire for the water temp sensor in the head. Both of these wires get pretty brittle over time, and may break internally, or at the connection to the butt connector. I have had to add wire to both of mine because of bad connections and wire degradation.
- Thread starter
- #55
Thanks again MoCoN! Gonna get with Brett when I get back in town in a couple weeks on the lines. I am planning on kinking and zip tying the kink closed on the rubber fuel inlet line until I get back so there is no more fuel vapor leak in the garage while I am gone. Pretty sure the vapor I smelled was from the remaining amount of fuel in the bowl draining out somewhere(manifold?) or somewhere once the engine is turned off as described above. Once the truck sits for a long time (10-12 hours) the vapor smell is signif reduced....I would imagine as that small amount of gas evaporates. I just want it to be safe while I am away since my water heater is in the garage.
Worst thing about the previous work on my truck is my PO just flipped my truck and didn't know anything about the previous owner/contact/or work done. I have been trying to track the other PO down for some time now.
Temp here at the beach in San Diego is really mild and I am starting the truck in a garage that is about 50-70 farenheit. I've never had a problem with the truck starting and idling with only two pumps of the throttle before I replaced with the current carb. It ran really consistently and once fired up I wouldn't ever have to pump the throttle to maintain an idle. Gonna get with my mechanic today to tell him about the plan to do hard lines and see if he would reccommend any other parts (gaskets,etc.) when I do the order. My plan is to get with Brett and the boys to run the lines and then see how it running afterwards and go from there.
Worst thing about the previous work on my truck is my PO just flipped my truck and didn't know anything about the previous owner/contact/or work done. I have been trying to track the other PO down for some time now.
Temp here at the beach in San Diego is really mild and I am starting the truck in a garage that is about 50-70 farenheit. I've never had a problem with the truck starting and idling with only two pumps of the throttle before I replaced with the current carb. It ran really consistently and once fired up I wouldn't ever have to pump the throttle to maintain an idle. Gonna get with my mechanic today to tell him about the plan to do hard lines and see if he would reccommend any other parts (gaskets,etc.) when I do the order. My plan is to get with Brett and the boys to run the lines and then see how it running afterwards and go from there.
- Thread starter
- #56
So any suggestions about the culprit of gas draining out of the bowl/float window when it sits for a couple hours. This is the biggest concern for me right now since it causes bad gas fumes after driving. Pretty f'ing dangerous. I think if I can track down and stop this from draining or evaoprating the other problems I am having (hard starting) will settle down. Hopefully the correct hard fuel delivery line will help as well. I am ordering gaskets and some parts to arrive while I am out of town so it would be great to get it all at once. Thanks!
- Joined
- Sep 26, 2003
- Threads
- 117
- Messages
- 11,199
- Location
- Lancaster, Ohio, USA
- Website
- www.tlcperformance.com
The problem is the fuel in the carb is hot & cooking off.
The solution is to install the correct 73 FJ40 fuel feed & return lines. By constantly returning excess fuel from the carb, back to the fuel tank, fuel temp and carb bowl temp will be significantly reduced.
The solution is to install the correct 73 FJ40 fuel feed & return lines. By constantly returning excess fuel from the carb, back to the fuel tank, fuel temp and carb bowl temp will be significantly reduced.
- Thread starter
- #58
Thanks Jim, that's great news! Hopefully the new lines will solve all my issues. Will update when I get back in a couple months and can set it up.
cruiserbrett
GOLD Star
- Thread starter
- #60
Yeah, that was a combo of a brain fart and too many wobbly pops. I meant weeks.
