New 4.6L stroker build

[cheito2]

Bring it over to PR, and we will break her in at 97*, well its about 75* now. I really hope all your hard work pays off this time. Can't wait to hear about how it turns out. Again good luck with everything.

[SilverXJ]

Again, I really really really hate you.

[SilverXJ]

Had it towed to the machine shop today. It will sit over night and warm up. They keep it 72* in there 24/7 for the machines. Tomorrow morning we will break the cam in. I hate breaking in the cam.

[Bodo]

GL! Have you made your sacrifice to the Horse Power gods?

Down here in the Panhandle of FL (where sailors and rednecks mingle) a ritual is performed. You make an offering of alcohol to the HP gods. A little goes in the carb, a little on the engine....some pleading words. Then the engine 'gets busted off'.

[SilverXJ]

I need to make a sacrifice to some god. As for the alcohol... I'm taking care of that right now.

[Exos]

I need to make a sacrifice to some god. As for the alcohol... I'm taking care of that right now.

LOL.... Best of luck to you Silver. Don't overthink it.

[SilverXJ]

Cam break in went well. Oil pressure was 50+ psi the whole time. Continues to be 50 while cruising.

However, The fan clutch developed a wobble so I had to replace that after the break in.. there was a big deal about the part though.. went back and forth with part numbers and pictures. The one that Advance brought had these teeth like pieces on the front that wouldn't let the clutch slide between the radiator and mounting studs. Checked the application and part number and most of the pictures showed those stupid things. Filed them down a bit and it was better but now the thermostat spring was making contact with the radiator. Finally used a pry bar on the motor mount and pushed the engine back enough to let it slide in to place. I should have switched to electric fans while it was down, but I didn't have more things to juggle when it first starts up.

The steering feels a bit odd. At first it had like a hard spot just off center at which point the pump would sound like it was under a lot of load. I don't know if we may have damaged the gear when trying to steer it on concrete while trying to set it up to tow, or if it was just cranky from sitting or if I am just not use to its feel anymore. I'll have to keep an eye on it.

The top of valve train is making a bit of noise. Started out with .020" preload and increased it to .030" with no change. Only thing I can think of is that the new lifters aren't playing nice with the 15w-50wt break in oil or that they still have air in them. I'll have to keep an eye on that as well. Still a bit nervous about it though.

Since the engine bay hasn't changed much I won't post any pictures of that. I'll post some images of my transmission cooler and filter install instead. I used Parker 836-6 (the -6 means An-06) and Jegs Push-loc AN-06 fittings. The 836 hose only comes in blue, is compatible with transmission fluid, and is rated to 302*F and 400PSI. I cut the quick connects and factory hoses off the hard tube and had a hose shop flare the tube for the AN fittings. The push-loc is no joke. Its not exactly push. Its more like heat up hose in hot water, lube barb and push with all you got. Doing it with a cold hose is a really really really bad idea. Russell, Jegs, Parker and Aeroquip all have their own versions of the push style fittings. I know that Russell and Jegs are pretty much the same things and both take the parker hose. Aeroquip hose is a bit different from what I have seen of it, but may still work with the Parker hose. I needed to use the fuel injection style hose clamps as the standard clamps would cut the hose. The red collars are supposedly just cosmetic, but I feel that they to put some tension on the hose. I did keep the factory push on fitting at the radiator only because i didn't feel like buying a new radiator now. Maybe in the future that will change. The fluid flows as follows: Out transmission --> Filter --> Tru-Cool cooler --> stock cooler --> transmission. I will later install a temp gauge. The cooler is mounted to the front cross member and radiator header panel using steel flat stock. I did not want to use the nylon zip tie type mounts through the radiator. I used them once on fan and it caused a leak in the radiator after a few thousand miles.

The only thing that I don't like is the factory quick disconnect on the radiator and the barbs on the cooler. I would have liked to use a cooler with an AN fitting, but the ones that came with the AN fitting were either too small (WxH) or too thick. I did also position the filter mount a not exactly where it should have been as I had to cut away part of the fan shroud to get the shroud to fit. Its not an problem though as fan blade is still a long away from the hitting the filter mount though.

Some info on the hose:
http://www.parker.com/portal/site/PARKE ... =836&Wtky=










I used the following parts:
All fittings are -06AN
1x Jegs 45* hose end; 100061
3x Jegs straight hose end; 100051
1x Jegs 90* hose end; 100071
1x Aeroquip 90* flare union; FCM2190
2x Jegs AN flare union; 110202
2x Jegs 3/8" NPT to AN adapter; 110106
1x Derale 3/8" NPT left port filter mount; 25750
1x Mobile 1 M1-204 filter (same as engine is using the smaller filter)
1x Tru-Cool LPD 4544 9.5"x11x.75" 3/8" barb cooler
~7' Parker 836-6 hose

[SilverXJ]

I have 40 or so miles on it. Hot idle oil pressure is 28psi, cruising is 48psi. The valve train is starting to sound better. Just a flutter now.

[SilverXJ]

And I like the 1" driver seat drop I did. Its easier to get into (not that it was that hard to begin with, but should save some wear and tear on the seat) and I feel better now that I have 2" between my head and the roof vs the original 1". $40 well spent there (manual brackets + welding).

[SilverXJ]

I was at the machine shop today playing with his DRBIII in an attempt to set the cam sync. I was unable to find it. Then I took a look at the firmware version and it said 1998... so I don't think I can set it with his unless somehow I get an update for it.

[SilverXJ]

Despite that constant knocking at idle and the rocker arm noise(get to that in a minute) it hauls ass. I do think I need to reset the computer as it is the AFT is pretty much dead on/ a bit lean in WOT, which is a new one to me... however it is a definitely a bit lean at idle on cold start. Either it learned a bad habit during cam break in or the injectors are partially clogged from sitting.

Now, the rocker noise. I'm thinking that I may have a partially clogged lifter. It does sound like lifter tick, just not as loud. If its a lifter sticking its only partially because it is fairly quiet. Perhaps I have a few lifters partially clogged with assembly lube. Possibly, as the oil I have in it is non detergent and I did find some assembly lube in the oil filter after cam break in that wasn't dissolved in the hot oil.

[rant]
Why couldn't they have simply enlarged the damn push rod holes in the head so you could pull the lifters through? Through all the changes in the 4.0L head why did they not think of that? Would it have been that difficult of a task? Every other engine I have worked on one can remove the lifters without taking the head off.. but.. noooo.. jeep had to be different.... heck.. every other inline 6 you can pull the lifters with out taking off the head... either through the side of the block or through the head. but, no.. one of the longest running engine lines and they couldn't make it easier to work on... one could simply pull a rocker arm, push rod and lifter to see what that specific lobe looks like on the cam or just to check/replace a single lifter.. [/rant]

[Muad'Dib]

Thats one of the things im going to do when i build mine... enlarge the holes in the head so i can pull the lifters out without removing the head.

[SilverXJ]

Great... now this engine developed another repeatable failure with the Isky cams... damaged cam bearings.

The first engine I built (lets call this engine A) was running fine until I noticed the crank end play was showing wear. In an attempt to fix that I killed the Comp Cam (wiped the lobes) in an attempt to polish the thrust surface while the crank was still in the vehicle. The valve train consisted of Harland Sharp rockers, Comp Cam lifters, Mopar performance valve springs, and the lifter bores were grooved to more oiling to the cam. Any how it was running fine until I killed the cam. Good oil pressure (35 psi hot idle), no odd noises. 1000 miles on engine A.

So, that engine was pulled and the cam and the cam lifters were replaced, keeping the rest of the valve train the same. Engine A2. The bearings were deemed good as there were very little hours on the dead cam. The cam bearings were perfect. So, in goes an Isky cam and Lunati lifters. Immediately something was wrong, low oil pressure (13 psi hot idle), odd lifter noise. Turns out the cam bearings were destroyed. My machinist blamed it on low oil pressure due to the lifter bore grooving. Fine, even thought the cam bearings survived with the Comp Cam. When he examined the Isky cam he found it to be out of round or something similar. 500 miles on engine A2

So we get another block, machine it, line hone it, and don't groove the lifter bores this time. Engine B. The Harland Sharp roller rockers were rebuild and all new bearings were used. Isky sent a new cam, which was checked and found perfect. Johnson lifters were used All bearing clearances were .0016"-.0020". New oil pump, etc. Cam spun freely in the bearings. Cam break in went smooth. Now, again i start to hear the odd lifter noise and the oil pressure starts to drop (was 25 psi hot idle at first, and ended at 18psi hot idle). So I pull the oil pan and guess what.. what bearings are damaged again.

So now my machinist is saying the Harland Sharp rockers have too large of an oil hole in the push rod seat and that is what causing an oil pressure loss. However, I find this hard to believe. 1) Engine A and previous engines with the Harland Sharp roller rockers and various lifters didn't show cam bearing damage, 2) the rockers are used by many people and I have never heard of such a thing, 3) the lifter controls the oil flow, 4) both failures happened with an Isky cam 5) Engine A didn't show any damage or wear to the bearing with the comp cam, yet engine A2 and B both show the came kind of damage.

My theory rests in the fact that Isky does something different to their cams. The machine the shaft (between the lobes) about 1/8" to make it look pretty. You've seen a 4.0L cam and it doesn't look nice, which I could care less about what it looks like. So, there is this well known cam harmonic after 5300 RPM in the 4.0L. My theory is that by removing that 1/8" of shaft material they effected the weight/balance of the cam and lowered the cam harmonic, causing the damage to the bearings.

And to tidy up a few lose ends, the Mopar performance springs provide for enough lift for either the Isky or the Comp before bind. The Isky cams showed no lobe wear, seat load on the springs is 100#. The Isky has left lift. No wear was found on the main and rod bearings in any of the engines, besides the thrust bearing.

Thoughts? Beside burn it to the found and collect insurance.

[gradon]

All these new pieces aren't installed in the cursed titan block? It is time to pay a visit to the witch-doctor/shaman/spiritualist and get that hex removed.

[SilverXJ]

Nope. New blocks.