Cam bearings failed yet again... please help

[dwg86]

I don't understand these cams being noisy. The cam I ran had an agressive ramp, duration to lift ratio (214 duration @ .050, with a .501 lift) and my valves didn't make noise. Also, if I remember correctly, my valve springs had a pretty high seat pressure, somewhere around 125 lbs (mopar performance springs).

[doublins]

Well, I will never find out what the real cause of this problem was- after mulling it over for awhile, I´m not willing to invest in this failed experiment of a motor again- rebuilding it has become an annual ritual going on year three now.

I´ve decided to go forward with a 5.9 magnum swap- and am accumulating parts for that, but will be parting out my old jeep stuff soon, including pistons, injectors, intake manifold, dual roller chain, throttle body, custom intake, roller rockers, the built head, valve cover spacer, and crank. I´ll probably scrap the block, but if anyone needs any odds/ends, sheet metal, anything from the engine, let me know. PM me if you want dibs on any of that stuff...

Thanks to all for the help and input you´ve given, but it´s time to move on to more reliable pastures.

-Chris

[Muad'Dib]

Its too bad that people like yourself have these bad experiences. It really gives these builds a bad rep.

[dwg86]

Well, I will never find out what the real cause of this problem was- after mulling it over for awhile, I´m not willing to invest in this failed experiment of a motor again- rebuilding it has become an annual ritual going on year three now.

I´ve decided to go forward with a 5.9 magnum swap- and am accumulating parts for that, but will be parting out my old jeep stuff soon, including pistons, injectors, intake manifold, dual roller chain, throttle body, custom intake, roller rockers, the built head, valve cover spacer, and crank. I´ll probably scrap the block, but if anyone needs any odds/ends, sheet metal, anything from the engine, let me know. PM me if you want dibs on any of that stuff...

Thanks to all for the help and input you´ve given, but it´s time to move on to more reliable pastures.

-Chris

I'm with you. I have a low mileage 5.9 on a stand that will be going into my Wrangler truck I am building.

[SilverXJ]

Thats a shame, but I can understand how you feel. The 5.9L should be an interesting project and has a lot of aftermarket support. What transmission do you plan on using?

[doublins]

Thats a shame, but I can understand how you feel. The 5.9L should be an interesting project and has a lot of aftermarket support. What transmission do you plan on using?

Yeah, I just picked up a donor Dodge Durango w/ a 5.9. I´m going to hold onto its auto tranny for safekeeping, but as a start, I picked up an externally balanced 5.9 flywheel, and a bellhousing from the dakota 3.9 (which had the ax-15), to allow me to run my ax-15 behind the 5.9. We´ll see how long the AX-15 holds up to the 5.9... Novak seems to think they´re pretty stout and able to hold V8 power, but there´s a big difference between a stock 4.0 and a 5.9- the AX-15 is supposedly rated similarly to the NV3500 series, at 300 ft*lbs of torque, and the 5.9 exceeds that at the flywheel by a bit... who knows. My rearend is an 8.8, so I should be all good there.

Anyway, I´ll try to part out the Durango as best I can and then scrap it to recoup as much money as I can from the swap- while I have the front end off, I´m replacing a fender, repainting my grill/fenders/flares/cowl/windshield frame, etc, replacing the hard lines for the brakes, repainting the firewall, cleaning up the frame, etc. So all in all it´ll work out to be a ¨freshening up¨ of the jeep overall.

I can´t even look at my stroker motor- it makes me angry just to see it in the garage... I´ve spent THOUSANDS of dollars since late 2010 on a motor that has failed three times in less than 15,000 total driven miles. Not to mention my time in labor, the constant downtime of the jeep every spring when I should be out driving it.... just a total and complete waste.

Hindsight is indeed 20/20 and after this I would never even have considered doing a stroker over a V8 swap.

[SilverXJ]

The AX15 should be just fine behind the 5.9L. They hold up to strokers fine so the 245 from the 5.9L will be ok. However, when you start moding the 5.9L it might be a different story.

Before you swap the engine in you may want to change the intake manifold pan as they are prone to leaking and letting oil into the manifold. A guy on ebay sells a 1/4" one for a good price (better than Hughes'). Also keep in mind that the heads on the 5.2/5.9 are prone to cracking between the intake and exhaust valve in the chamber. 90% of the heads that come off are cracked.

[doublins]

The AX15 should be just fine behind the 5.9L. They hold up to strokers fine so the 245 from the 5.9L will be ok. However, when you start moding the 5.9L it might be a different story.

Before you swap the engine in you may want to change the intake manifold pan as they are prone to leaking and letting oil into the manifold. A guy on ebay sells a 1/4" one for a good price (better than Hughes'). Also keep in mind that the heads on the 5.2/5.9 are prone to cracking between the intake and exhaust valve in the chamber. 90% of the heads that come off are cracked.

Thanks so much for the info!

I´ve been reading up on the 5.9 for a couple of weeks now, and was already aware of the intake plenum gasket and the head cracking issue, but thank you still for sharing the info, in case I hadn´t come across it yet, and in case someone else reads this.

P.S. the wiring differences between the 98 5.9 and my 98 4.0 are so minimal that it´s laughable. Furthermore, there´s even a chance that my JTEC ECU might even be able to to be flashed with the 5.9 programming- it already has all of the injector driver pins, etc. Something that could be convenient to discover... I will report back the verdict once we try this. If not, I do have the ECU from the Durango that can be reprogrammed to eliminate the A/T.

One more note regarding the AX-15- its not the horsepower of the 5.9 I´m worried about, it´s the 335 lb*ft of tq.

-Chris

[SilverXJ]

A quick google shows that several people run the AX15 behind a V8 with a few having failures. There is also this http://www.rsgear.com/products/transmis ... 84%A2.aspx

I've recently purchased a Zj w/ a 5.2L and have been reading about the 5.2L engine. I did know before hand about the plenum and head issues. The extra power is nice coming from the worn out 220,000 mile 4.0L in my 95 ZJ, but its underwhelming especially considering the gas mileage.

Its interesting about the JTEC PCM.

[dwg86]

Hey Chris, there are several 5.9 engine engine swaps on www.jeepforum.com. I would get a 5.9 manual pcm for your swap. Since your jeep is a 1998, you have a CCD data bus. Any V8 pcm that is made for a manual trans will have a CCD data bus. If you get an automatic PCM it could be either a CCD or PCI data bus, depending on the year.

[doublins]

Hey Chris, there are several 5.9 engine engine swaps on http://www.jeepforum.com. I would get a 5.9 manual pcm for your swap. Since your jeep is a 1998, you have a CCD data bus. Any V8 pcm that is made for a manual trans will have a CCD data bus. If you get an automatic PCM it could be either a CCD or PCI data bus, depending on the year.

Thanks!

Re: CCD bus, www.hotwireauto.com has a pretty good chart you can use to figure out ecu compatibility here:

http://www.hotwireauto.com/?page=mopar-eng

And, I´ve read just about every single 5.2/5.9 magnum swap threads on the internet over the last two weeks

Every day when I come home I´ve been finding more big brown boxes waiting for me... found the bellhousing in a junkyard, found a 5.9 external balance flywheel to use (5.2 is internal balance, 5.9 is external balance, so you can´t use a 5.2 flywheel on a 5.9 without some work), got my headers, motor mounts, and my welder is just itchin to get fired up and get this puppy sitting between the rails.

I´ve spreadsheeted everything with part numbers + costs, including junkyard sourced parts, so hopefully I´ll have a complete writeup when I´m done with part numbers and step-by-step instructions for others to follow.

[dwg86]

Cool! Post a link to where your Jeep build is going to be (being this is a 4.0 stroker website). I would like to follow it.

[doublins]

Cool! Post a link to where your Jeep build is going to be (being this is a 4.0 stroker website). I would like to follow it.

I'm planning on doing a build thread on www.jeepforum.com, will post a link here when I create it.

[doublins]

For anyone that cares to follow along, I have a build thread for my Magnum swap over on jeepforum. Making good progress!

http://www.jeepforum.com/forum/f22/my-m ... s-1516649/