Beginning Fitech 2 barrel

[Crankyolman]

The other day I finally got all the money together to buy a Fitech 2 barrel FI.


I ordered it and most of the other parts I thought I might need. Today it arrived I was excited and quickly opened the box to check it out. Everything looked great except when I got to the gasket, which was the wrong one They sent a gasket for a 4 barrel with a 2 barrel throttle body. This isn't really a big deal since I had already purchased the correct gasket just in case I needed it but it doesn't exactly inspire confidence in Fitech.



I have a week off work beginning next Monday and my plan is to see if I can get it all installed and up and running while I'm off. I plan on documenting it here and possibly in the my thread in the Pris section. I'm a little nervous about screwing this up but figure other people have done it so there is no reason I can't. I have one thing left I'm waiting on...the fuel pump which will be an in tank, then I will drop the tank and begin my installation.

[Crankyolman]

While I'm thinking about it I have a question for you smart people out there.


Because my truck, engine and intake manifold are all '72 there is nowhere on the intake manifold to install the the temperature sensor except on the thermostat housing, which I'm sure isn't ideal. The original temp sensor is tiny, I'm sure it's smaller than the 3/8" the fitech sensor is and really I like keeping my original gauges functional.



So does anybody know of anywhere else that would be a better place to install the temp sensor?

[babywag]

Odd that there is no CTO in passenger front intake coolant crossover.
My '72 CJ5 w/304 has one there.
That is the typical spot to use.

There are drain plugs on each side of block as well.

[Crankyolman]

Odd that there is no CTO in passenger front intake coolant crossover.
My '72 CJ5 w/304 has one there.
That is the typical spot to use.

There are drain plugs on each side of block as well.

It seems odd to me too but I just went and checked yet again and the only hole is that tiny hole on the drivers side where the original temp sensor is. While I was out there I rechecked the date code on the engine, which is 505N10. Near as I can decipher that means AMC 360 that left the engine plant on May 10th 1972 (literal translation is 5=1972, 05=May, N=360, 10= day of the month), which corresponds to the month the truck was built. The original timing cover is also date coded somewhere around that same date. But all that said the heads are 993s which are late '71s, so I am thinking maybe the intake is late '71 as well.


So I guess that leaves me with only 2 choices, the thermostat housing or a drain plug. I'm not really sure I like the idea of mounting it in a drain plug but maybe that's the better way to go or maybe put a T at the place the heater hose connects at the back of the intake?


Whatever I choose I guess I need to do it quick, tomorrow is my last day of work before my vacation starts and I really need to have this done by the time I go back to work.

[babywag]

You wouldn't be mounting it in a drain plug, plug comes out, sender goes in.
A tee would work on rear heater hose fitting as well.
Later models used one and installed a cto there.

[jblue1555]

you could install temp sender for Fitech and use the digital monitor for temp guage

[babywag]

you could install temp sender for Fitech and use the digital monitor for temp guage

He would probably have to drill tap it larger for that or use an adapter(not ideal).

[Crankyolman]

You wouldn't be mounting it in a drain plug, plug comes out, sender goes in.
A tee would work on rear heater hose fitting as well.
Later models used one and installed a cto there.

Thank you, I'm leaning towards the Tee

you could install temp sender for Fitech and use the digital monitor for temp guage

You see the problem there is I don't like the look of the hand held controller, I like the original look and the fitech controller doesn't look good. '72 was the last of the Kaiser era, the only thing AMC is the engine and paint. I like the look of the Kaiser era dash so I prefer to keep my dash looking and functioning as original as possible. Plus there is the fact that the original sending unit is only 1/4" and the fitech is 3/8" so it won't fit without modification and that isn't going to happen. I'm not replacing that heavy cast iron intake either, after engine overhaul it took me 2 days to get that intake back on and I hope to never have to remove it again.

[Crankyolman]

Yesterday I went down to my local performance shop to buy some hard fuel lines and AN fittings so I can begin installing the fuel injection...but they were closed. It seems they are closed on Sunday and Mondays So I had to go back this morning. Fitech uses AN6 fittings which can be a bit of a problem because AN fittings are 37 degrees and the hard lines I bought had 45 degree fittings. Fortunately I work on aircraft for a living so I ran up to work and re-flared them to 37 degrees with AN fittings.



Then I began modifying the sending unit to use an electric fuel pump. That hasn't really been going all that well and required a trip to Lowe's for some wire but I am almost ready to put the sending unit back in the tank.



I did get the throttle body mounted, which wasn't really a joy either. One of the mounting holes was slightly off and had to be lightly reamed to get it to fit. That and sending it with gaskets for a 4 barrel rather than a 2 barrel kind of has me worried about everything.



Then there was the O2. I wanted to put it in the header collector but didn't want to remove it to drill a big hole in it and getting a drill in to drill that big hole wasn't very easy and I couldn't do it where I wanted to, so I had to settle for drilling it a little aft of the collector. Then when I went to put the clamps on that hold the bung on they were too big, so had to run to the store again to buy new smaller clamps.


So the next step it to finish the fuel pump install and get the hard lines installed, then hopefully start running wires.

[Crankyolman]

I know this is probably pretty boring without an pictures but hopefully I can get some up later on. In the mean time I guess you will just have to read my updates.


So, I got the fuel pump installed and the tank back in. Got the fuel filter hooked up. Fitech requires a 40 micron filter, although the one I bought doesn't show what direction to mount it. I got all the wiring hooked up, that was actually quite easy, and right now I am running the fuel lines. This would have been easier if the existing fuel line was metal and not plastic but it was plastic so I had to run whole new lines. It was very tempting to just run it all with flex line but I prefer hard line where I can so that's what I'm using.



I ran into even more problems with the temperature sensor. I was going to put it in where one of the drain plugs goes but when I got ready to remove the drain plug it looked considerably smaller than the temp sensor so I didn't remove it. I tried to remove the fitting that connects to the heater so I could put a tee there but it's been there for 47 years and seemed to have the attitude that it is not going anywhere, so I defaulted to plan D and put it in the one hole that it fits it on the thermostat housing. I will see how that goes but my eventual plan is to see if I can get some barbed fittings that can screw into a tee and splice that into the heater hose. I figure that will give me more accurate readings than the current setup.



Hopefully some time this afternoon I will have this all wrapped up and ready for a test drive.

[Crankyolman]

I got everything more or less finished yesterday. I say more or less because the fuel lines still need a few more clamps but because of the boxed frame I ran into some issues that will need longer bolts or self tapping screws to fix, but it is secure so I can finish clamping at a later time.


After getting the fuel lines run I coupled the feed and return lines together and flushed them out so there wasn't any debris in the system, then hooked everything up. I followed Fitechs setup to the letter, turn the key on and off several times, check for leaks, once all the leaks are gone turn it on and leave it on while you do the initial setup with the hand held controller. Did that and fired it up for the first time and it scared the crap out of me. It started but RPMs were all over the place and it was surging badly. So I shut it down and checked everything. Everything looked fine so I started it back up. It was still surging and running rough so I hit the gas and it got a little better. I let it run a while and it continued to get better as it ran.



Then I took it for a very short drive. It had to be very short because I had purposely nearly run it out of fuel so removing and reinstalling the gas tank would be easier. So I drove it down the street and around a bit. It hesitated just after going around corners and after one particularly sharp one it died. I'm assuming that was because the fuel in the tank sloshed and it gulped some air. After driving it around a little bit it was running and starting real nice.


I went to the gas station this morning and got a gallon and a half of gas so I can get it to a gas station, then I will drive it around and let it learn and see how it feels. I know absolutely nothing about fuel injection or what things should be done to tune it but we will see how the self tuning goes and go from there.



I have a few pictures for you guys There really isn't all that much to take pictures of but here they are.


This first one is simply when I first opened the box.



And the incorrect gasket that came with the kit, this irritates me a bit because it's a pretty basic thing to get wrong.



Then FI installed



And the breather back on



I had to do a little adjusting to the bottom of the air filter housing to keep it from hitting the front side of the throttle body but a couple of minutes with a 3 pound hammer and it fit fine. Unless you look close you don't really see there is a fuel injector under there, the only real giveaway is the stainless steel fuel line coming off the left side.



So now I'm off to the gas station to see how it runs and give it a full tank of gas.

[Crankyolman]

The trip to the gas station and back went well for the most part, although the temp reading was 165-170 which seemed a bit lower than it should have been. My thermostat is 185 but the truck does a good job of cooling the coolant. I don't know if that is because the Fitech temp sensor has a problem ( A known issue) or if it is because it's located in the thermostat housing.


Another issue was I completely filled the tank and when I looked under the truck before leaving the gas station there was gas dripping. I was wearing good clothes so didn't get on the ground and crawl under to see where it was leaking, I just figured I'd get it home and then check but when I got home it was no longer leaking, so I have no idea where it was leaking from.



It runs well on the fuel injection, although it actually took more cranking this morning than usual to start it but I attribute that to the FI not getting a chance to learn but it has now driven 10 whole miles on FI and ran very well. The throttle is now super touchy and the truck seems to coast better when I let off the throttle which is something I didn't expect. It also didn't hesitate or die when I went around corners so I guess that when I drove it yesterday it was just a case of the 2 gallons gas that were in the tank sloshing around.


I didn't mention exactly how I did the fuel pump so I guess I should. Instead of removing the vent line and replacing it with a 3/8" tube, I realized the pickup tube I already had was already 3/8 with a 5/16 vent plus a second vent that was on the tank from when the original sending unit was in, which was invented. The second vent had a barbed nipple in it already so I just needed to buy one that is 3/8 instead 5/16 and my return was all set. So I shortened the existing pickup tube, gave it a slight flare so it would hold the line better and clamped the fuel pump on to it and used the vent attached to the new sending unit as the new tank vent. It was actually pretty easy.

[babywag]

Cool. You will never want a carbed vehicle again, especially after you tune/tweak it. After it is dialed in you will be very happy.

And yes the thermostat housing is a poor place for temp sensor.
You could always just drill a hole and tap it on passenger front coolant crossover.

[Crankyolman]

Cool. You will never want a carbed vehicle again, especially after you tune/tweak it. After it is dialed in you will be very happy.

I hope that is the case. The carb has never really been problematic but that broken idle jet always bothered me because I had no way to know if it was set correctly. It did have a problem with carbon building up due to my shot drive to work and back, every so often I would have to take it for a drive at highway speed to blow out the carbon. That said it does seem to run smoother (I know, everybody says that) it certainly accelerates smoother and quicker, decelerates slower, which seems weird but it's not that the FI is slow to slow down it just seems to coast better like the engine isn't slowing it down any more.


Tuning and tweaking it is pretty intimidating to me, I don't really understand most of the stuff that goes on and I read about it and people seem to use a lot of abbreviations I don't understand and I'm afraid to do something that might hurt my engine.

You could always just drill a hole and tap it on passenger front coolant crossover.

I know I could but would be afraid of messing it up, plus I try to never do anything to my truck that can't be undone and put back to original just in case some day these old trucks become valuable in original numbers matching condition. For a short time I was using an electric fan with a thermostatic switch in the thermostat housing. The switch was set to come on at 185 and turn off at 175, my thermostat is a 180 so once the switch was tripped the fan never turned off. This makes me think the Fitech sensor is reading a bit low but it will work until I figure something else out. I read on that Fitech FI website that people swap the Fitech sensor for this proper Delco one https://www.amazon.com/gp/product/B0...ea25bee2cecb82
I think I will go ahead and buy that one but I also think I will see about putting it in the heater hose.

[babywag]

Be VERY VERY difficult to prove a "numbers matching" deal on any FSJ.
AMC just didn't do it, and any records they do have are sketchy or don't exist.

You should be able to find a brass fitting(s) that'd work for hose install of sender in plumbing aisle?
Sender is just NPT