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Yet another... Build thread for an xj on 40s and one tons in norcal

3" exhaust did not really do much, new tune did not do much. still falls on its face .

Oil looks like crap, about 900 miles on the new motor, 3rd oil change, and cut the filter open - it has a good amount of metal in it. I am pretty sure the camshaft is flat, so I am pulling the motor and bringing it back to the machine shop that long blocked it. Kind of bummed, but everything is pointing to a flat cam. Good compression, but has no balls whatsoever.
 
I was just thinking about your xj and wondered how the motor issue was going.
Bummer to see it not working right.
Was it a new camshaft? Any theories as to why it went flat?
I know with flat tappers you can only have a cam shaft profiled so much before the edge of the tappet digs into it.


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We arent 100% sure if its the cam but all roads lead to a bad cam. Hoping everything else is salvageable .
 
I didnt read the whole thread so you may already no this, but for a flat tappet cam you need to run oil with at least 1300ppm of zinc and crucial during break in. Unfortunately the epa has cut the zinc to 800ppm on all oils except for racing oil. The only oil you can get from the local parts places that has the correct amount, is valvaline racing oil, although you can order other racing oils from summit, amazon etc. Ive done LOTS of research on this since my BBF jet boat motor is also flat tappet.
 
Oil companies are changing their formulations due to newer technology in today's autos and for emissions quality right? Help me out, my understanding is that the extra zinc is to protect the cam due to the high amount of force between the lifters and a flat tappet cam. Do newer autos have less force between the cam and lifters?
I understand that it's just as important during normal operation, and especially crucial during break in.

You can get a concentrate that you add to regular oil each interval, 6 oz per I believe.
I found some locally (Rislone 3x concentrated engine oil supplement) ~10$ per 12oz. and am currently using it to break in my stroker. I'm using Rotella t4 engine oil.
the concentrate has a disclaimer saying something about potentially damaging catlysts, I have the Ca emissions 2000, and will report anything unusual.

Bummer to hear about your issues with the motor man, I've been inspired by your rigs
 
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Russ pottenger provided me with break in oil. Special comp cams break in oil.
 
And even after break in i ran comp cams muscle oil with exta zinc
 
Oil companies are changing their formulations due to newer technology in today's autos and for emissions quality right? Help me out, my understanding is that the extra zinc is to protect the cam due to the high amount of force between the lifters and a flat tappet cam. Do newer autos have less force between the cam and lifters?
I understand that it's just as important during normal operation, and especially crucial during break in.

You can get a concentrate that you add to regular oil each interval, 6 oz per I believe.
I found some locally (Rislone 3x concentrated engine oil supplement) ~10$ per 12oz. and am currently using it to break in my stroker. I'm using Rotella t4 engine oil.
the concentrate has a disclaimer saying something about potentially damaging catlysts, I have the Ca emissions 2000, and will report anything unusual.

Bummer to hear about your issues with the motor man, I've been inspired by your rigs

it was reduced due to the epa mandating that catalytic converters needed to last longer and was found that the zinc in the oil is what was killing the catalyst, hence the disclaimer on the concentrate. Most all newer vehicles run roller cams so it is mostly a concern with older flat tappet cam vehicles. Some of the big name oil companies will have a zddp (zinc) percentages list on there website for each type of oil so you can get the right stuff.
 
Ive been drooling over 40 spline ARBs for front and rear . I guess a guy has gotta have goals. I would like to put a 40 spline ARB in the rear at some point in the next 18 months to start. Then eventually the same up front.
 
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I like wasting time for no reason . No not really. So i pulled my motor for fun. Actually it probably has some major internal failure like a flat cam seems to be suspect

Anyone have one of these plates that go between the engine and the flexplate for sale? I cracked mine .




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If no one else has one, I think I have 1 or 2 in my back yard.
Can run without it, if necessary.
 
I have one from the Zj that's going to the pick n pull soon. Not sure if it's the same with it being in a Zj.


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SO the machine shop called and said the motor was internally fine, compression consistent around 210 before they tore it apart. I am totally confused as where to go next with this thing, its surely gutless , ive had Jes and Josh both ride in it, we are talking no real power...

Maybe ill try clocking the dizzy in a bunch of different orientations, and also throw my RAD shifter on it, and go from there. I cut the tabs off the dizzy already, so ill play with indexing a little to see if that helps, and hopefully being able to hold gears and lock/unlock the Torque converter will also help a ton, hold gears longer into the power band.
 
Have you looked at the trans. When i switched from auto to manual it was crazy how much power i got back. Not saying manual is the answer but there was definitely something wrong with the trans i pulled out. It was robbing a ton of power.


Thats strange they found nothing wrong though.
 
Have you looked at the trans. When i switched from auto to manual it was crazy how much power i got back. Not saying manual is the answer but there was definitely something wrong with the trans i pulled out. It was robbing a ton of power.


Thats strange they found nothing wrong though.

Funny you say that, I am almost at the point were I want a manual now, just to see if it is the automatic robbing power. I would love a granny low option thats fairly bolt in .


Gordon when you did your swap , you needed:
AX15
Pedal assembly
master and slave cylinder
what else?
 
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Thats it aside from like shifter boots in the trans tunnel. I had a doner with a full wiring harness and ecu. But that is not needed. A few simple mods and it will work fine. The ecu let me smog it properly tho. No questions asked.

I believe you can re flash the ecu and turn it into a manual ecu.
 
So everything was soaked in gas, and was washing out the rings. The head gasket was about to blow too- possibly due to retarded timing . It was running insanely rich, like super rich and they said it looked like the timing was probably retarded way too much in addition to running rich. Compression was 200 on all 6, which is right around 9-9.5:1 or so.

The question is what was causing the rich condition and what caused the retarded timing. I think the dizzy could have been off ? or somehting was causing the timing to retard, and I am going to go back to the stock tune and try 27lb injectors and see what that does for now once I get it back along with a new o2 sensor and the stock distributor.
 
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