New 4.6L stroker build

[SilverXJ]

The only place for them to fit without being over the throttle body and all its fun sensors that don't like water. No problem with them being over the front any how. IIRC its a bit better for pulling hot air out at road speeds vs. being more toward the rear for crawl speeds..

[buschguy]

SilverXJ -That is one sharp Jeep! Where did you get your hood vents? After my TJ is finished up, my 190K mi XJ will get some lovin'. I vented the TJ, but was looking for a style that fit the XJ better. I like those. Are there screens or drip catches below?

[SilverXJ]

Got them on ebay. Came off a Pontiac GTP, but don't recall what year. They come with screens and a drip pan... I eventually would like to rework the drip pans though.

[SilverXJ]

700 miles on it now. I have been running midgrade for the past 200 miles without pinging. Its running a bit rich in the top end (like 11:1 afr), but haven't had a chance to tune it yet. Yesterday was fairly warm and I put 100 miles on it that day. It ran well. never broke 210* on the temp gauge and that was coming back from a job having a bit of fun on a back road. After this tank of midgrade is done I am trying regular gas.

I replaced the flex plate and the tapping sound is still there. I have a torque converted on order. One other sound that I have been noticing is a slight tap coming from the valve cover. Best way to describe it is a quiet flutter, which from research is probably the sewing machine noise from the roller rockers. However, there is a chance that these rockers maybe a bit worn from being run on the previous engine. I'm going to be looking into that this weekend. Its not very loud. Its hard to head when you are in the engine bay, but most noticeable from the interior of the Jeep.. but its so quiet that if I roll a window down or after 2200 RPM it can't be heard.

I also have to replace a door hinge pin this weekend. I noticed that I sometimes have to close the door twice and on inspection I can lift the door up with an audible click. Top hinge is lose. Its always something, ehh? Oh.. and I also need to fix that stupid squeak from the back seat... how many years was the XJ in production and they never fixed that latch design so it wouldn't squeak? And now the dealer I get 25% off at is closing down. DC brings the fail.

[SilverXJ]

I did two runs today to log the AFR. They were both WOT runs and damn it does pull.. even with a lacking AFR.




Definitely needs some work. The richest it gets is 10.3:1 @ 4800 RPM. If I was running boost that would just be about perfect.

I'm planning to get it to 12.5-13:1.

[the_wrench116]

this is just WOW. i mean wow somebody buy this guy a beer. just got some more goodies for my build we will see if she rusts out first or i get the motor done. thanks for all the info.

[SilverXJ]

Well, unfortunately I believe I have found the source of the knocking noise. To refresh your memory the knocking isn't very present on cold start up. After driving a while it becomes more audible however it seems to disappear after 2500 rpm. I replaced the flex plate with no luck.

I pulled the oil pan thinking that perhaps I missed something while installing it, like a connecting rod to main girdle clearance. I checked the main girdle and all was good with no marks from anything coming in contact with it. I'm not sure what I was doing at the time, but I moved the crank and heard a click. I then forced the crank fore and aft and noticed quite a bit of play. So, I pull out the dial indicator and magnetic base.

Crank end play is .016". Factory measurement is .0015"-.0065". .0095" greater than the upper end of stock, more than double. I will be talking to the machine shop about this tomorrow. Fawk. The machine shop was paid to assemble and blue print the engine. I feel that if the bearing doesn't show wear then they are at fault there.

So, looks like the first step will be to replace the thrust bearing with a new thrust bearing and see if that helps. If that doesn't help.... well... is there such thing as a thrust bearing with a thicker thrust surface? If not.. looks like I will have to replace the crank... or maybe have the current one welded and re cut in the thrust surface.. possible?

If the crank needs to be replaced I am not looking forward to pulling the engine again. Also, since the machine shop sourced the crank and blue printed it I don't think I should have to pay for any parts nor work done by them.

So once again my XJ is down.

One question... I researched the main bearing journal width(1.271"-1.273") for the thrust journal and it never changed from the 258 to the 4.0L. However, is that measured from thrust surface to thrust surface on the crank?

[the_wrench116]

the first step is to check your clearances which you did. second can you verify that there isn't a restriction of oil to that bearing. third see what options are available for your #3 (i think) main bearing which is your thrust bearing good luck with the machine shop they dropped the ball. go hit them with a stick. one did the machine shop give you a sheet with all the clearances written down? as far as measuring the crank thrust surface i would use a vernier caliper and measure surface to surface on the crank.

[dwg86]

Sounds like the same noise coming from my stock 4.0, 112,000 mile, 2003 TJ. Started doing it when it was cold. Now I notice it goes away when I get above 2000 rpm.

My stroker is ready to go in at any time.

I hope your machine shop makes everthing right.

[SilverXJ]

I measured the bearing journal today and it is right around 1.272" , where it should be. Also measured the lower bearing installed on the cap and it was 1.260" (I think it should be 1.270". but not sure on that number". The difference is .012", and given slight errors in measuring it is right around what I am seeing for end play. Also, one thrust flange on the bearing measures .10" thick and the other .094".

So, it appears that the bearing wore, or was faulty. If it wasn't faulty, what would cause it to wear so quickly? Perhaps there was a problem with the flex plate or the torque converted that caused excess pressure against it?

The machinist is going to stop by the storage unit tomorrow and take a look at it for me.

[the_wrench116]

so you have what maybe 2500 miles on this motor so far? and it already chewed through .006 on the thrust bearing surface. that just doesn't seem right at all are you seeing coper yet on the bearing? can you get a replacement bearing to look at them side by side as well as measure them and to well replace it?

sorry that your having so many problems good luck with it and the machinist.

[SilverXJ]

It has around 1200 miles on it. Copper visible on the thrust flanges of the bearing, but that is the way it should be. I odn't know if I can get the thrust bearing alone.

[yuppiexj]

The stealership has it

2000 block (same part number in the 1994-1996 parts catalog too)
8350 7084 BEARING PACKAGE, Crankshaft Thrust, Standard Size
8350 7086 BEARING PACKAGE, Crankshaft Thrust, .001" Undersize
8350 7090 BEARING PACKAGE, Crankshaft Thrust, .010" Undersize

https://www.dodgeparts.com has it for $22 and change.
the part number won't come up in the search but if you drill down engine/crankshaft and bearings/bearings/BEARINGS, Jeep, Thrust Bearing - 4.0L - 4.0L 92-04 you'll find it.

HTH.

[Muad'Dib]

What lifters did you decide on?

And alot of the parts you said you got from "Falcon". Is this the ebayer "falcon"? Doesnt look like he has been selling much of anything lately....

[SilverXJ]

Yes, the Ebay falcon. I contacted them off ebay. I went with the comp cam lifters. Nothing special, just their regular ones.