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Clay's Build Thread

556K views 5K replies 145 participants last post by  Skerr 
#1 · (Edited)
I have been contemplating posting a build thread for awhile. After viewing some of the current ones I got really pumped! I also figured that as long as I was going to be asking for help fixing stuff I might as well have it in the thread... so here we go. My 16 YO son, Clay, and I are building his CJ5. It's a 79 that I acquired in a boat/Jeep trade nearly 2 years ago. I got it for myself but I don't fit well, so I got a 7 and gave him the 5. He is really stoked about building the Jeep and I can't think of a better father/son project. Clay will be doing the work while I supervise ;). The 5 has a 258, T18A, D20 with axles from an 85 CJ7, D30 and AMC20. Gears are 2.72. We will probably go to a 3.73 in the future. It will get the RC 2.5" lift, Procomp 9000 shocks, and a urethane bushing kit (already purchased). It also has a FG tub which will require a bit of glass work. We had already completed the frame resto when we discovered that we didn't do it right. So we took it back down to bare metal again, finding some rot and a few cracks. We should have those repairs made in the next couple of weeks. After that the frame gets POR-15 and black implement paint. In the meantime, we'll be working on getting the engine painted and installing the MC2100. In these pics Clay is prepping the T18A for paint. He wanted to paint it silver with a red stripe, but I put the Kibash on that! So he settled for a silver tranny and red shift levers... when we get there. He plans to paint the rig International red (tractor paint) with a silver tub floor. Hmmmm... maybe! It MIGHT look good. We just finished watching the entire Season 2 of the Rat Patrol... so guess what HE wants to mount up!?!? :laugh:
 

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#3,720 ·
10-4 Trent. It's a 1.08 venturi, however it has size 50 jets. We could not find smaller jets locally. The only place that had Holley jets is a speed shop, and he wanted to know why I wanted 47s or 48s... he asked if they were going in a golf cart!! :(

Clay did NOT pop the rubber diaphragm all the way through the carb wall, so we need to pull it back off and fix that. He DID install a gasket on the power valve.

I can't get it to run smooth. I think it's getting too much fuel. When we turn it off, fuel is gassing off and floating up out of the carb, thick, white, gaseous smoke.

Clay tightened down the oil pan bolts a bit. It was dripping oil in the front, below the crank, in the valley portion of the pan. He said "Oh No!", and he had a stripped bolt! He handed it to me and there was metal imbedded in the bolt threads. I'm thinking the PO stripped it and heli-coiled it. Clay ran a tap into the hole, and I found a longer bolt. For the moment, all of our oil leakage has stopped.

Got his oil pressure, volt, temp, and tach connected and operable. Exciting stuff!
 
#3,723 ·
Thanks, Mike. I don't have the same level of assurance that you do though. I'm hoping I can get the carb to smooth out.

Good stuff, Skipper! Drove mine around the block today, too. Light at the end of the tunnel?
I can see the light presently, but it's not getting any closer right now. I don't understand why I can't get it to smooth out and run well? It's puzzling. Clay and his guests took a trip down to the river yesterday evening, and I almost, drove his Jeep down there for Ks and Gs!! But I didn't think it would be fair! Besides, too much to do for that little foray.
 
#3,724 ·
Hey Scott, I don't carry the phone much especially on weekends but I sent you a text and you didn't reply :confused:

Setting the timing to 8-10 BTDC should be fine for now, lock it down and look for other issues.

I don't know anything about the MC 2100 but I would recommend a vacuum gauge, full vacuum at idle should probably be somewhere between 20-23 Hg. If it's low, like 15-18 Hg you may have a vacuum leak. I set the idle mixture by turning the screws all in and then backing out 1.5-2 turns, hook the gauge up to full vacuum and adjust one screw to find the highest vacuum reading, then turn it back in 1/8 turn, then adjust the other side. Changing the timing will change vacuum readings so you would need to re-adjust to fine tune.

There should be plenty of data on the MC 2100, if you have the 1.08 venturi model you are on the right track. Did ya'll rebuild the carb?

If the answer is yes, did ya'll soak it or spray out the holes with carb cleaner and air? If ya'll didn't soak it, a gallon can of Berryman's carb dip would be a good starte.
 
#3,725 ·
I was like you... I didn't have my phone on me when you texted back, and then we had company, and I just plain forgot about it. I did get it, and I appreciate it. I wanted to pick your brain about the idle issues. I will have to break down and get a vacuum gauge.

Yep, the carb is a 1.08, and it is fresh rebuilt. Clay missed a step, however, and it's possible it's getting too much fuel into the accelerator pump. Gotta pull the carb again (that makes maybe 5 times), and I'm worried about chewing up the gasket. I can't believe how many times I think "we got that done" only to have to go back and remove something again for a forgotten detail!

Carb was soaked, scrubbed, rinsed with clean water, and blown out with air. Gas sprays nicely when hitting the accelerator, but the carb stumbles badly for a moment before the engine cathches up. The second hole from the top seems to work best.

Still can't find a vacuum leak, but all of the symptoms are there.

Welcome Home Bill!! :wave:
 
#3,731 ·
I don't know that it has slipped, but I do know it idles better at around 12-14*. We fixed the step that Clay missed, pulling the rubber nipple through the carb wall at the accelerator. Now it idles at 500 RPMs.

I always thought you should find the vac leak first, as that affects the carb tune, IF there is a leak.

Just a thought, vac assist brakes? What other things are vac operated? Maybe plug off one vac operated item at a time in case a diaphragm is leaking or something.

If it seems like there is supposed to be a hole between the ones there for the accelerator pump, maybe tweak the linkage a bit to shorten/lengthen it.

Random thoughts.. :rolleyes:
Yes, vac assist brakes, but aside from the vacuum advance, that's it. I was talking with Bill earlier this evening, and he suggested the same thing you are... maybe more than one leak. I WAS going to listen for a leak with a piece of tubing, but the battery is too low to crank it, so it's on charge. I HAD it running, and didn't get to that step yet. So I'll try it again tomorrow.

Another random thought..... you can adjust the linkage on the MC2100 to control a. how soon the accelerator pump shot comes in and b. how strong the shot is. The first pic adjusts rate, second pic adjusts strength.

Edit: Never mind. I see your 2100 looks nothing like mine did....
I can make the same adjustments you show in the frst pic, but I don't have the holes in the second pic. I have the "flat" spot out of the carb now. That seems to be rectified by seating the rubber nipple in the accelerator pump. I have immediate carb response now. HOWEVER, once I goose it once or twice, it tends to "runaway". It does not idle back down. It revs up and holds at 2100 RPMs. If I close the choke it kills it instantly, but if I open it quickly enough the engine will continue to idle at 500. If I shut it off, white smoke comes up out of the carb, which I believe is vaporizing fuel?? I still think too much fuel. In regards to a vacuum leak, if I close the choke slowly, compensating for the additional air, there is no change.

I'm no motorcraft expert, but it sounds like something is wrong with your float. either too high, sunk float, bad needle valve seat ect. did you check the fuel height in the float bowl?
Float is set at 1/2", not sunk, new needle valve. Sitting in the shop, not moving. Float shouldn't be a problem under these conditions. Keep the ideas coming...

If you look back a week or so I posted a picture of the gasket with the number on it.

Bill
Posted up the part # on his thread, so he's got it.
 
#3,727 ·
I always thought you should find the vac leak first, as that affects the carb tune, IF there is a leak.

Just a thought, vac assist brakes? What other things are vac operated? Maybe plug off one vac operated item at a time in case a diaphragm is leaking or something.

If it seems like there is supposed to be a hole between the ones there for the accelerator pump, maybe tweak the linkage a bit to shorten/lengthen it.

Random thoughts.. :rolleyes:
 
#3,730 ·
Dadamsnv said:
My iPhone does it automatically, I'm no magician ;)

Where did you find that one piece gasket? I did my oil pan sealup yesterday, and I'm not very sure it came out well. I may have to redo it. I won't know until I finish putting in the rest of the drive train and start it.

Those bug boxes look great! Some good craftsmanship there :)
If you look back a week or so I posted a picture of the gasket with the number on it.

Bill
 
#3,732 ·
Do you have a couple return springs on it? I can't see it good right now on my phone, but make sure you have a couple return springs to close the throttle. If you do, make sure the choke's high idle cam isn't falling in place holding it at a higher idle.
 
#3,736 ·
I have a single, stout spring. The throttle MUST be returning all the way, because I can't move it any farther with my fingers. The choke cam definitely is not falling in the way... I have paid attention to that as well. Although I wish it WAS that cam, cause then it would be solved!

A detail I did not mention that could be important... There is a screw with a spring that can be adjusted in or out that affects (geeeeeez, my mind is completely going... CRS disease!) idle, I guess the return of the throttle plate?? It is screwed all the way down tight. The engine will idle at 500 RPMs if I let it warm up and don't mess with the linkage. If I twist the linkage two or three times, the RPMs jump up to 2100 and hold there. I can take a screwdriver and back off that adjustment screw, ever so slightly, and the idle will start to come down. If I come off that screw one full turn the idle does not immediately change. It continues to run at high RPM, then after a bit it sounds like it runs out of gas and dies. I can keep it running by moving the linkage, but if I don't, it shuts off. Got all that!? :D

I may be beating the dead horse, but it sounds like you did a bench float height adjustment, but did verify the fuel level while the jeep is warm and idling? I've always had good luck with the bench set, but who knows.
Yep... bench adjustment (kitchen table, rather). I did not actually have to make any adjustments as it is right on 1/2", so I was happy! I have visually seen the fuel in the bowl, with the float floating, by removing the top of the carb during operation. Of course, I don't know how significant that is, because it did nothing for me!! But I did see the fuel in the bowl. The next day, all the fuel had drained out. We "fixed" the rubber nipple in the that pokes into the bowl. It was not seated, and I am thinking that is why the fuel left! But I have not confirmed that yet. Off tomorrow, so maybe a big CARB day!?

sounds like your on the home stretch, drag AJ over and let him at that carb, while you put the rest together. You are the skipper, so delegate.:p
Oh how I would like to, but AJ is having physical complications associated with his larynectomy. Not sure what is going on for him, but the tube the doctors created is closing up. Not good...

Did you do anything with the engine like the valves? The valves may be leaking causing idle problems.
No... we didn't do any engine work. It was running very good when we got it, so we didn't tear anything apart in the engine. Just cleaned and painted.

Figured out my wiring mistake with the headlights, and now Clay has HEADLIGHTS!!! YAYAYAYAY! Granted, the PO has ONE Halogen bulb and ONE regular 'ol bulb! Did that guy not take any shortcut? Gotta buy a matching headlight.

MoC, how good are your headlight buckets? One of Clay's sets lower than the other. I have inspected them carefully, and I can't see any reason for it.
 
#3,733 ·
Skerr said:
.

Float is set at 1/2", not sunk, new needle valve. Sitting in the shop, not moving. Float shouldn't be a problem under these conditions. Keep the ideas coming...
I may be beating the dead horse, but it sounds like you did a bench float height adjustment, but did verify the fuel level while the jeep is warm and idling? I've always had good luck with the bench set, but who knows.
 
#3,738 ·
Scott,

love the progress! I am looking forward to seeing action shots...that day was one I thought would never come!!!
 
#3,739 ·
Scott, when ever you adjust the idle screw( the one you mentioned in the first paragraph) you would want to "blip" the throttle linkage so it will Be at the position, you set it at. I other words , push the throttle linkage to increase rpm's and let it snap back. I would also spray all the linkage with something like WD40 , including the shaft the butterfly's are attached to.

I only adjust the idle mixture screws after the engine is warm. A vaccum gauge can be used when setting the screws. Proper idle should be between 6 and 700rpm's . I usually do this by ear. Adjust them 1 at a time, when finished with 1 readjust the curb idle. And do the next one.

I have had issues with the butterfly's sticking to the carb base , and not returning to idle. A quick blip of the linkage would return the engine to correct idle.

Do you know how many turns out the mixture screws are, if it is wanting to die at idle, you might back each one out in 1/4 turn increments to see if that helps it.
Bill
 
#3,742 ·
Scott, when ever you adjust the idle screw( the one you mentioned in the first paragraph) you would want to "blip" the throttle linkage so it will Be at the position, you set it at. I other words , push the throttle linkage to increase rpm's and let it snap back. I would also spray all the linkage with something like WD40 , including the shaft the butterfly's are attached to.

I only adjust the idle mixture screws after the engine is warm. A vaccum gauge can be used when setting the screws. Proper idle should be between 6 and 700rpm's . I usually do this by ear. Adjust them 1 at a time, when finished with 1 readjust the curb idle. And do the next one.

I have had issues with the butterfly's sticking to the carb base , and not returning to idle. A quick blip of the linkage would return the engine to correct idle.

Do you know how many turns out the mixture screws are, if it is wanting to die at idle, you might back each one out in 1/4 turn increments to see if that helps it.
Bill
A quick blip doesn't do it. I know just what you're talking about. Goose it and let it go. You just get a big rev, and afterward it goes back to the roaring 2100 RPMs. The screw/spring on Clay's carb is identical to yours, but Clay's is cranked all the way down to try and sustain an idle. I suppose that would keep the throttle plate cracked a bit, causing this high idle. Funny how that just occurred to me. BONK!! If I back off even a half-turn, the engine will eventually start to "decelerate" and die.

Mixture screws are at 1 1/2 turns right now. I can't be certain, but I THINK I'm hearing a "peak" right around that range. I still plan to get a vacuum gauge and do it that way. I have run the screws in and out and in and out... might pull the carb and go through it again just to be sure we didn't miss something else!!

I have not lubed the butterfly only because I am stubborn, and I refuse to admit there's a chance some dirt is in a fuel passage!! It soaked in a can of carb cleaner overnight, then was scrubbed with a brush, then was rinsed with fresh water, then was blown out with 100 psi of air, then reassembled on the kitchen table, and I carried it out to the shop and I installed it. And I didn't drop it! So I'm guessing no trash or sticking throttle plates. But I'll confirm that tomorrow after I tear it down and check it out!! :D :rolleyes: :eek:
 
#3,740 ·
A good picture of the idle adjust screw may be helpful, some PO may have put a different screw in, you said it was all the way in, it shouldn't be. The spring shouldn't be compressed all the way.

Bill

On edit, I know there are a boat load of different 2100 carbs, but the throttle linkage is very similar.

Automotive fuel system Motor vehicle Gas Auto part Nut


This one idles at 650/700 rpm.
 
#3,741 ·
The pourpose of the 2 return spring is in case 1 breaks. I read this somewhere , something to do with NHRA requirements. I think it a good idea.

Bill
 
#3,743 ·
My schematic for the front parking lights shows a green wire to one side, a green w/tracer to the other side, and a white wire shared between the two lights (if I'm reading it correctly). The schematic indicates a ground to each housing. When I created the housing ground wires, I connected the plugs, and VOILA... LIGHTS!! Cool, huh? The only problem is that the switch is NOT turned on! So back to the drawing board...

Shouldn't there be a brown to one side and a green to one side for turn signals?


All morning I could not get into JF. It kept saying the server was inaccessible. Did anyone else have this problem? I had no problems accessing other sites.
 

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#3,745 ·
Skipper I had the same problem up here I jus could not get it to load.

As far as the high idle, try pouring a Margarita down the carb you know to loosen it up.
Har har :laugh:

I'd try rum n' coke. Tequila make her clothes fall off, and I'm sure you'd prefer to keep the tub on for right now.
 
#3,746 ·
as for your carb problem. I think you are on to something with the idle screw cranked down. Don't use it as a bandaid. turn it all the way out, get someone in the cab to keep it alive, and play with the idle screws until she runs smoother, THEN turn the idle screw in to keep her alive. And for real, a vacuum gauge is really an awesome tool for this stuff. It makes life so much easier. I don't know if you mentioned it, but what is your base timing set at? Did you use a timing light? Is it possible your light is bad/out of adjustment? With a vacuum gauge, you can tune your base timing to get her into the ballpark without using a possibly faulty light.
 
#3,747 ·
I have a good Craftsman timing light which I believe to be accurate. It has never caused me any issues in the past, so I will say it is right on. I agree I need to have that idle screw backed out. I still need to buy a vacuum gauge, but it is not in the budget at this time. Soon, though... soon!

I pulled the carb off awhile ago, and I went through it. Blew out all the passages... they all seemed to be fine. I found the bowl to be empty again, so all the fuel is draining out. What is causing that? Wouldn't it have to go through the jets? I found Clay had installed the accelerator pump spring (that tapered spring) backwards. I'm not sure that would make any difference, but I turned it around according to the diagram. This puts more direct pressure on the little red rubber diaphragm behind the pump diaphragm. Maybe that's how my fuel was leaking out??

So it's all assembled again, bolted back down for the umpteenth time, battery is all charged up, I start to crank it... rrr...rrr...rrr...rrr...rrr...rrr...rrr...rrr... you know how it goes. But no fire! I grab my cup to get a little gas out of my temporary fuel tank. It's a pain, but I want to prime the carb. I have a 5 gallon can sitting on the ground next to the Jeep. It has the fuel line running into the top of the can with the cap on to reduce evaporation. It had about 4 gallons in it day before yesterday. We didn't run it last night. Can is empty today!! I mean completely empty. Bone-freakin'-dry!! Somebody stole my freakin' gas!! They removed the fuel line, poured the gas into whatever, and reinserted the fuel line. No way 4 gallons evaportaed in a day and half. Nothing else missing... praise the Lord!

Now, in conjunction with this, Beth came home yesterday from teaching a 4-H class on forestry. She found the screen porch door closed with the cat locked on the porch. She left it propped to allow the cat access in and out. She also found our kitchen door locked, but not latched. She did not enter the house, but went and got a neighbor, who went through our house before she and the kids entered. Nothing amiss!! She is going to have to start carrying.

Nobody has a key to our house!
 
#3,748 ·
Skerr said:
I have a good Craftsman timing light which I believe to be accurate. It has never caused me any issues in the past, so I will say it is right on. I agree I need to have that idle screw backed out. I still need to buy a vacuum gauge, but it is not in the budget at this time. Soon, though... soon!

I pulled the carb off awhile ago, and I went through it. Blew out all the passages... they all seemed to be fine. I found the bowl to be empty again, so all the fuel is draining out. What is causing that? Wouldn't it have to go through the jets? I found Clay had installed the accelerator pump spring (that tapered spring) backwards. I'm not sure that would make any difference, but I turned it around according to the diagram. This puts more direct pressure on the little red rubber diaphragm behind the pump diaphragm. Maybe that's how my fuel was leaking out??

So it's all assembled again, bolted back down for the umpteenth time, battery is all charged up, I start to crank it... rrr...rrr...rrr...rrr...rrr...rrr...rrr...rrr... you know how it goes. But no fire! I grab my cup to get a little gas out of my temporary fuel tank. It's a pain, but I want to prime the carb. I have a 5 gallon can sitting on the ground next to the Jeep. It has the fuel line running into the top of the can with the cap on to reduce evaporation. It had about 4 gallons in it day before yesterday. We didn't run it last night. Can is empty today!! I mean completely empty. Bone-freakin'-dry!! Somebody stole my freakin' gas!! They removed the fuel line, poured the gas into whatever, and reinserted the fuel line. No way 4 gallons evaportaed in a day and half. Nothing else missing... praise the Lord!

Now, in conjunction with this, Beth came home yesterday from teaching a 4-H class on forestry. She found the screen porch door closed with the cat locked on the porch. She left it propped to allow the cat access in and out. She also found our kitchen door locked, but not latched. She did not enter the house, but went and got a neighbor, who went through our house before she and the kids entered. Nothing amiss!! She is going to have to start carrying.

Nobody has a key to our house!
Oh that sucks about your house. I would get her a tcp .380 it's small enough to fit in a wallet sized holster.
 
#3,749 ·
Scary about the house man. That's not good at all. I've been forced to consider getting ADT or something for my hood :/

In other news, I have the carb drain out on my rig over a few days to a week, and the accel pump has no pressure on idle, so I'm gonna say its normalish :confused:
 
#3,754 ·
We had ADT in a previous house when we lived in south Florida. It was a decent system, and they were a decent company. No complaints.

What do you mean "no pressure on the accelerator pump at idle"?

Looking real nice. Kept up the great work!
Hey johull... thanks for dropping by. We visited your town a few weeks ago for a beach weekend. We had a wonderful time.

Sounds like teenagers to me, on the gas, or could it be Jake or Clay came home, needed gas went to the house and left?

Bill
Nope... wasn't the boys. I'm thinking a no account son of a pretty decent neighbor. Whoever it was seemed to know that can of gas was sitting there. And why didn't they get the Dewalt tools, or battery charger, or welders, or anything else?? Of course, I'm glad they didn't. Beth said our garage door was open about 3' as well. It has an opener and it was closed when she left. We are trying to explain the coincidences, but we can't really. Someting strange to say the least!

It's not normal for the fuel bowl to be empty after a few days, or even a week. My WAG- gravity , and seeping past the needle valve, thru the fuel pump back into the gas can.

Fuel pump, a interesting idea. The engine sat for 3 years. It's very possible the diaphragm as dried out. It could be pumping enough at a higher rpm, but barely enough at idle. AMC fuel pumps, pump enough at idle for some gas to return to the tank via the filter. So a quick check would be install the filter, and the return back into the gas can. While the engine is running, pull the return line out of the can and have a look to see if there is gas coming from the line.

The fuel pump should pump a given amount of gas in a set period of time while cranking. unfortunately I don't know that amount or the time.

Bill
I will check that out Bill. Good idea. Although the pump seems to be keeping up with the engine with no issues while we are running/revving the engine.

If you pull the carb again inspect the passages. I've read that using high pressure to blow them out can force some of the plugs out
Took the carb completely apart earlier today and blew out all the passages. Did it again a short while ago with my neighbor. All of that is good.

AJ popped over again about 8:00 this evening. He must have some kind of sense when I need help! I had an old Cushman that I gave to him (it needed more work than I was interested in doing). He has that thing running/driving like a sewing machine! He was pleased to see our progress, and he wanted to hear it run. I explained the gas situation, and he went home and brought back some gas! So we fired it up and he listened. He fiddled around. he tweaked and prodded. He adjusted and adjusted some more. Then he shook his head! For AJ, that's a bad sign! He revved it up and put his hand over the top of the carb, and then he proclaimed that there is no vacuum! He says the carb ain't working at all. The leak/s are so bad that it does not pull on his hand. I never thought of doing that! So we pulled it. He took it apart. We mounted it. We ran the engine. We pulled it again. I am really starting to dislike this carburetor. And he discovered the gasket between the adapter plate and the intake is leaking by looking at the discoloration of the gasket. Then he found where I had used Ultra Black (RTV) to help make a seal on part of the gasket, and he reprimanded me for that! So a trip to town tomorrow for gasket material, and maybe we'll have this thing licked??

After we ran it and shut it down the gas was vaporizing inside the intake. It comes out in a thick white cloud. He pointed out the gas was leaking through the carb and dripping. We backed off the idle screw enough to allow the throttle plate to cose, and that stopped. But it is still leaking! Oh yeah, he also adjusted the float to a lower level... says there is too much gas in the bowl.

Pics show AJ and Clay tearing down the carb yet again, the carb sitting normally, and with the gas vaporizing.
 

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#3,751 ·
Sounds like teenagers to me, on the gas, or could it be Jake or Clay came home, needed gas went to the house and left?

Bill
 
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