Just Got Myself Into A 6...

Hum, one thing i just notice, external pump must be mount below the tank. Those pump are more pushing than sucking, putting it over the tank may cause problem.

I put mine allong the side frame rail so it's under the fuel tank.

 

Thought of that... And I know it's recommended, but I never really understood the reasoning behind that:

fuel is is sucked from the bottom of the tank via the pickup tube and then propelled by the pump.
mounting the pump lower than the tank, or pickup tube, would only add more hose to the system.
by keeping the hose length at a minimum and the pump parallel with the fuel outlet I'm inherently reducing the amount of strain the pump needs to exert.
Even after long stretches of non use the fuel filter stays full and provides a "prime" reservoir for the pump.


venting correctly is number 1 on the priority list.

 

Johneyboy does make a point. High pressure pumps are notorious for not sucking fuel. They are great at pushing, but terrible at sucking. I haven't fired the system up as it's not plumbed yet, but on my flatfender I have a low pressure pump that will feed the high pressure pump.....


*I'd still start with the vent.

 

I'm betting vent more than anything...
its a pressure seal cap so I know the tank isn't getting proper venting.
I have no distinct vintage car smells in the garage and my wife hasn't complained..

 

it's just logic, think when you syphon a gaz tank or whatever, you need to put the input tube higher than the output so it will work well. The same thing occur about pump location, if it's below the lowest point of the fuel tank , pump will be feed with positive pressure as soon as is primed, so no effort is needed from the pump. So putting the pump above the highest point of the fuel tank will make the pump to be less efficient because it harder to keep the feeding into the pump. Ultimately pump could loose pressure power and make the injection to not work properly, the ecm may shut down the engine to prevent any damage.

i did a little research on holley about fuel pump location, here's what i found in there instruction:


8.3 Fuel Pump Installation
1. Do not mount the fuel pump higher than the lowest point of the fuel tank.




As for the vent, if it work trought the cap by now i don't think is a issues. You just loose the fuel vapor that normaly get into the charcoal canister and sucked by the pcv hoze of the engine . You lose some mpg's but that the only problem it can cause.


So i really think that you're problem is the pump location. I run a afi tbi kit, and i ran into some fuel problem just like the one you describe and finaly it was my pump and the fact thet my tank was getting pressurize because i wasn't venting it at all. I did install a new pump and the charcoal canister and i had no problem since. So knowing you don't have the pressure problem, the only one is the fuel pump location.

 

If it's a sealed cap then that IS most likely the issue. I kinked the vent on my 300EX one time putting it back together and same type of symptoms. Would run fine until it seemed like it was running out of fuel. Let it sit or pop the cap and it would run a bit longer... Finally found the kinked vent....

 

...update...

ran 2 vent lines up into the wheel well and zip tied to the turn signal...
No further staling issues...

Vapor canister and check valve next...

 

While I have been addressing my fuel vapor issue I decided to tackle a few other odds and ends that need some attention and adjustment.

I haven't been happy with my hyd clutch setup..
Clutch works fine, but I feel its not operation at 100% efficiency.
With consistent driving I have a noticed a small drop in fluid, but no external leaks from the system. I purchased a kit way back when from this guy and have been generally happy with it..

I decided on swapping my MC and Slave for "better" units, often these kits use generic quality rebuilds. I did notice however when I was pulled the slave that there is some play in the pushrod to the fork. Is there a rule of thumb on how long the pushrod needs to be? When in the compressed position should I be able to move the clutch fork, or should this be a rather ridged connection?

 

have my plunger rod with me today.. a trip to Fastenal is needed at lunch.. who sells a M10 1.25 rod in a universal kit?
I think my current setup is short enough that I'm getting a good throw, but only at full stroke..

Things that I have noticed while driving:

If I coast into a parking spot with clutch depressed I sometimes cant pull it out of gear until I give another full pump to the pedal.. an issue when my front bumper is up another cars *** already.

Same situation at a stop light if not in neutral.. seems like I'm loosing pedal.. possible internal hydraulic leak
I have a good amount of pedal movement before anything happens..
had this with my Brake MC and the rod was too short...

 

Evap system is coming together...
Cleaned out some room on the driver side firewall for the bracket..
(thankfully I had the premonition to get it hot dipped at an earlier time)

Evap canister is an older Delco unit.. with Fresh Air/Tank/Purge nipples
I am debating where to tie the purge into.. I think I can get away with T'ing it to the EGR valve since its operated by the CTO switch.. Eventually I could always swap CTO's for a dual circuit, not the single I have currently..





Gas tank vent and rollover proved a little difficult.. real estate back there is slim and I didn't want to drill any additional holes into the body. I ended up using a left over hood prop rod bracket mounted to the rear roll cage foot plate.. the MTS unit came with a stainless bracket that fit perfectly.. Still have to plump the valve to the engine compartment, but the heavy lifting is done..

 

also not so important, but I got the front bumper and winch mounted..
ended up using my winch off the YJ, just put some new rope on it.. and ill be putting the new Rock 12.8 I purchased on the Wrangler.

yes, I know its not the correct color emblem... but I thought it matched better

 

Actually isn't that correct for a '73? The earlier emblems used Kaiser Jeep's colors? And AMC used blue and red?

 

id be happy if you are correct, but I think its the opposite.
I've personally only seem the blue and red on early FSJ and commando's..

either way.. matches the truck

 

did the clutch last night... it functions, that's all I can say..
this is the new pushrod I made... same length as the one I removed with a coupler/jam nut so I can +/- the length while in the truck. Once I get it dialed in Ill prob take it back out and make a solid one..

 

I just want to say it again that your Jeep is absolutely beautiful! Keep up the good work, I'm looking forward to hearing your first trip reports with it, complete with lots of pics.

 

a BIG thank you to Cora for taking some this this past week and allowing me to play around...


Was able to take the 6 out for an hour or so and put through its paces...
Some general driving impressions first...


The Jeep drives great, and I'm not just saying that.
tracks very well down the road, steers well, accelerates and brakes almost like a modern vehicle.
Driving a T18 deff takes some getting use to on the road. 2 and 4th are easy, upshift to third is a slow go and easy to miss.
Engine is beautiful... a pleasure to step on the gas!
Jeeps runs about 2,500 RPM in 4th gear at 60 mph.
I can easily get it to 85, but I'm out of gear . . . almost like a built in safety feature.
long why cruises are easy, but thirsty.
Country roads with a 55 MPH limit are best.. I can get it in 4th and keep the RPMS down.


Off Road Performance


It was odd, I had to lock hubs before popping into 4low, but there were no sway bars to disconnect
Jeep hit the woods very naturally..
Trail riding was nice, the narrow stance will keep pin striping down and an ATV trail is very doable.
A big difference is the LWB. Lots of wide turns and reverse gear was needed to stay on trail.
Rear tire carrier/cage is perfect for pivoting during some of these maneuvers in tightly wooded trails.
Lack of sliders was discovered quickly, some scratches in the aluminum will be a reminder if not sanded out..
Selectable front locker is a must for any LWB Jeep, was toggling the switch on/off frequnetly.
Suspension needs lots of breaking in or they just don't flex like they do now..
With only 500 miles on the rig and NO weight in the rear of the truck I think they need some time to give a bit.
Gearing is fantastic, wouldn't change a thing 94:1 in LOW was enough to creep down a couple rather steep grades.
the couple rocks on the trail were a quick reminder that airing down is a must.
Cant really judge performance since I was bouncing on and off. (Round 2 hopefully with sliders)


Overall a very successful outing some design changes I noted:


-Power steering cooler might be needed.. lots of turning when trails are tight..
thought i might have overheated, but could also have been a bad brake flare leaking fluid..
-more slack in front hard brake lines.. nothing broke loose, but I can see a possible problem (or it was a bad flare)
-more HYD spares (flare tool, etc.. all custom, no off the shelf parts if needed)
-SLIDERS - SKIDS
-gear tie downs in the back.. or tool box rack
-phone / GPS holder somewhere in Jeep is needed
-Shift tower boot and Tcase boot.. lost my radio remote through the floor in a quick stop
-T case shifters need to be re angled..
-TBI running slightly rich... 12 psi fuel pressure.. might need to tune down a bit..
-more wheeling will lead to a OTK of the TRE...


Some "full flex" shots followed by some more pictures form the day

 

Very Nice , Congratulations!

 

Awesome! Glad to see some trail shots. The leaf springs will get softer, but it will never ride like a coil. Drop some air and it will make a huge difference in the way it rides on the trail. It will reduce the wear on the Jeep and yourself!

 

this was just a quick romp in the woods to test suspension, drivetrain and lockers..
didn't expect much in the way of rocks in Western New York...

for sure next outing will be properly aired down..

I was thinking about getting a couple hundred pounds of whatever to keep in the load space for a few hundred miles..
Aside from my spare and carrier, there is no weight behind the front seats.