I saw you struggle to keep the screwdriver centered while priming. What I've done on a few motors is grind the teeth off the drive gear of an old distributor and chuck that up. Makes priming much easier
Woodrow's 97 Green TJ (NOT SO) Moderate Build
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I saw you struggle to keep the screwdriver centered while priming. What I've done on a few motors is grind the teeth off the drive gear of an old distributor and chuck that up. Makes priming much easier
On the cam bearings, the recommendations are conflcting to a degree. Newcomer are recommending a trimetal bearing (ACL) while Clegg and Golan are recommending a bi-metal (Durabond)
https://www.onallcylinders.com/2021/01/13/bearing-down-engine-crankshaft-cam-bearing-basics/
The bimetal is going to tolerate more misalignment and have more conformability, while the steel backed tri-metal has more load capacity as long as the thinner babbit material is in place. It's only 0.0005". You'll see recommendations to have the 4.0L cam journals line honed as there were alot of alignment issues with them in manufacture.
My thinking on this big difference is Clegg and Golan are acknowledging the unknown condition of the cam journal and recommending the more conformable aluminum bi-metal. Newcomer are assuming a higher caliber prep with a tri-metal steel backed bearing.
https://www.onallcylinders.com/2021/01/13/bearing-down-engine-crankshaft-cam-bearing-basics/
The bimetal is going to tolerate more misalignment and have more conformability, while the steel backed tri-metal has more load capacity as long as the thinner babbit material is in place. It's only 0.0005". You'll see recommendations to have the 4.0L cam journals line honed as there were alot of alignment issues with them in manufacture.
My thinking on this big difference is Clegg and Golan are acknowledging the unknown condition of the cam journal and recommending the more conformable aluminum bi-metal. Newcomer are assuming a higher caliber prep with a tri-metal steel backed bearing.
What are the cam suppliers recommending? What did MoPar use? (cam & bearing)
The alignment issue at manufacture you mention is both interesting and annoying (and not particularly surprising to one not enamored with OEM Chrysler things). That could explain my extruded bearings. It would suggest that probably occurred fairly immediately and then stabilized. I expect if I just pulled the cam and replaced the bearings, it would happen again, even if the cam were checked and found to be straight.
In regards to the one we had where we replaced a bent cam due to the OPDA shaft seizing, none of the bearings were extruded and when I put the cam in, it turned freely with no uneven rotational force to do so. If that bending didn't extrude the bearings, the forces to do so must be very high.
I'm there with you on OE quality.
Most of what I've seen written on this implies that the bearings squeezing out are typically from error in installation. Cocked, journal in the block slightly under size and the bearing driven in, the cam journal was oversize/tight and installed anyways, or the bearing deposition had a high spot. They're not meant for the high loads the crank bearings see. Cam bearings are often installed by the machine shop. These problems don't seem nearly as common with V8s. Maybe these shops are having difficulty with the longer tools needed to install the 4 bearings in an I6. Golen certainly don't sound like they're using a higher pressure than stock spring the way they vaguely describe their cam selection.
Thankfully these things can be checked with simple tools. Whether it is the cam,or the cam bearing bores.or the installation of the bearings.
I'm definitely not going to cry bad installation when the bearings are squished out on the bottom side. Away from spring pressure.which is what I've seen.
I'm also not going to say the springs golen and clegg use are stock. Stock is extremely light and does not tolerate higher lift cams at all.
Yes, but there is that 120-200 lb end of things that can take .500 lift and then there are folks running 400 lb LS springs (they might not need).
Is there confirmation that high spring pressures will squish bearings? Wiping lobes makes sense for sure but overloading the bearings seems like a bit of a stretch.
If you consider the inertial dynamic forces at high RPMs, it's a legitimate concern.
I had a really good discussion with Russ Pottenger about a lot of things. He is just full of engine building knowledge and happy to share. I hesitate to quote him on much because of my lack of experience. But with regard to Jeep 4.0 cam and cam bearing installation he said he will put the front and rear bearings in first, then the cam and spin it by hand to check for resistance. He then removes the cam and repeats the process for each of the central bearings. A pretty smart way to confirm the block and cam are straight.
edit: and figure out where the problem is if extra resistance is found.
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Russ is definitely a good source of info. He spec'd all my parts for me.I like his method of checking imbetween cam bearing installs.
When you put a crank or cam in you want to check for resistance with each step. If it suddenly becomes harder to turn it needs to come back apart. It was why i mentioned having you check the rotational resistance of your current cam setup and then again once its back together
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Smarter people than me mention that as a possible cause. I'm no engineer.with the length of a 6 cyl cam, flex is more of a concern. Higher lift,more spring pressure and rpm can flex the cam and put more load on the center bearings.
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Automotive rock bottom? No, but man am I sick of it.
I recently posted about my stroker issues (rear main and front harmonic balancer seal leaks with extruded cam bearings noted upon inspection after pulling the oil pan). More to come on that, hopefully with minimal drama.
I have 3 or 4 rigs I drive regularly (TJ, Dodge pickup, Mustang GT and ‘94 GMC flat bed). My wife’s car makes 5 that I maintain. At this point, I have fully bought into the vehicle maintenance thing. Partially because I enjoy the challenge and the work and a little bit because it’s better economically for me, because new cars are so ridiculously products of government and customer requirements for over-the-top electronic BS (@Zorba) and because buying less new cars is better for the planet.
Regardless of how I got here, here I am:
The TJ is likely going to need a rebuilt or new motor. That sucks because: A) I bought a new motor from Golen 20K miles ago. B) I have other more interesting things to do on the Jeep so I can do this stuff:
C) wheeling season is still underway. D) My wife, or anyone else, could rightly say “how much F-ing money are you going to spend on that thing!”. She, to her credit, has NOT said that.
Then there are the other 4 vehicles…
1) My tow rig, an ‘08 Dodge 3500 CTD got an ATS Allison swap several years ago which is STILL having issues. I don’t have time to mess with it so its at a local shop that I trust to either sort it out or I’m selling it. I thought it might be TCM tune related, but it seems to be the torque converter. That was replaced under warranty not too long ago but apparently there is a new ATS TC that will fix itT
. The TC is a $2K part that ATS will warranty (3 years later, despite 1 warranty) but I will pay the labor.
2) The GMC flat bed is a water truck on the property during fire season and an extra truck otherwise. Its old and had 277K when the OD stopped working but I try to keep it up. In that vein, I drove it out to the shop where the tow rig is getting transmission work on Friday (you know, to keep the fluids moving around, plus I like it). In the parking lot, this happened:
The passenger front CV axle exploded and fell all over the parking lot (red arrows). New last year. So I replaced it with another Chinese part from Autozone in the lot. NOT how I had planned to spend my afternoon. When I was done, the truck wouldn’t start. I recently replaced the 4 year old battery (which had a bad cell) for this problem. I’m guessing I have a ground leak draining the battery as it always starts right up at home where it sits on a trickle charger. Luckily, the shop lot is at the top of a hill and I could start it by rolling downhill and popping the clutch. I’ll figure that out later.
3) My wife’s ‘17 BMW X3 has been a great car but it has 160K on it so we have been looking for a replacement for a year. Here she is when we traded the ‘13 (Right) for the ‘17 (Left).
She really likes this one but we both agree the new BMWs look awful. I’ve driven comparable Mercedes, Audi and Porsche SUVs and none seem worth the money and all are over burdened with electronics. Maybe a Volvo? We had an ‘85 245DL wagon which we both loved back in the day but ever since Geely (China) bought Volvo, I have been turned off. This should be easy but its not!
4) The ‘12 Mustang GT
is my most reliable vehicle but It needs a new rear end (whine is really loud at freeway speeds/80 mph). Certainly in my wheelhouse now but I don’t have time!
Should I sell the Mustang , buy a new tow rig, use the tow rig for a fire truck and get a CRV for my wife? NO. But it’s tempting.
I recently posted about my stroker issues (rear main and front harmonic balancer seal leaks with extruded cam bearings noted upon inspection after pulling the oil pan). More to come on that, hopefully with minimal drama.
I have 3 or 4 rigs I drive regularly (TJ, Dodge pickup, Mustang GT and ‘94 GMC flat bed). My wife’s car makes 5 that I maintain. At this point, I have fully bought into the vehicle maintenance thing. Partially because I enjoy the challenge and the work and a little bit because it’s better economically for me, because new cars are so ridiculously products of government and customer requirements for over-the-top electronic BS (@Zorba) and because buying less new cars is better for the planet.
Regardless of how I got here, here I am:
The TJ is likely going to need a rebuilt or new motor. That sucks because: A) I bought a new motor from Golen 20K miles ago. B) I have other more interesting things to do on the Jeep so I can do this stuff:
C) wheeling season is still underway. D) My wife, or anyone else, could rightly say “how much F-ing money are you going to spend on that thing!”. She, to her credit, has NOT said that.
Then there are the other 4 vehicles…
1) My tow rig, an ‘08 Dodge 3500 CTD got an ATS Allison swap several years ago which is STILL having issues. I don’t have time to mess with it so its at a local shop that I trust to either sort it out or I’m selling it. I thought it might be TCM tune related, but it seems to be the torque converter. That was replaced under warranty not too long ago but apparently there is a new ATS TC that will fix itT
. The TC is a $2K part that ATS will warranty (3 years later, despite 1 warranty) but I will pay the labor.2) The GMC flat bed is a water truck on the property during fire season and an extra truck otherwise. Its old and had 277K when the OD stopped working but I try to keep it up. In that vein, I drove it out to the shop where the tow rig is getting transmission work on Friday (you know, to keep the fluids moving around, plus I like it). In the parking lot, this happened:
The passenger front CV axle exploded and fell all over the parking lot (red arrows). New last year. So I replaced it with another Chinese part from Autozone in the lot. NOT how I had planned to spend my afternoon. When I was done, the truck wouldn’t start. I recently replaced the 4 year old battery (which had a bad cell) for this problem. I’m guessing I have a ground leak draining the battery as it always starts right up at home where it sits on a trickle charger. Luckily, the shop lot is at the top of a hill and I could start it by rolling downhill and popping the clutch. I’ll figure that out later.
3) My wife’s ‘17 BMW X3 has been a great car but it has 160K on it so we have been looking for a replacement for a year. Here she is when we traded the ‘13 (Right) for the ‘17 (Left).
She really likes this one but we both agree the new BMWs look awful. I’ve driven comparable Mercedes, Audi and Porsche SUVs and none seem worth the money and all are over burdened with electronics. Maybe a Volvo? We had an ‘85 245DL wagon which we both loved back in the day but ever since Geely (China) bought Volvo, I have been turned off. This should be easy but its not!
4) The ‘12 Mustang GT
is my most reliable vehicle but It needs a new rear end (whine is really loud at freeway speeds/80 mph). Certainly in my wheelhouse now but I don’t have time!
Should I sell the Mustang , buy a new tow rig, use the tow rig for a fire truck and get a CRV for my wife? NO. But it’s tempting.
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Sell the Mustang to free up capital. Fix the tow rig because you've owned and maintained it for however long and it's cheaper to fix than replace. Fix the motor in the TJ with either another stroker or a decent reman 4.0 (would be hard since you've gotten used to the power).
And for the wife, I wouldn't overlook something like a Honda Pilot, Acura MDX, or a Mazda CX70 (or CX90). They all have higher trims that are very nice. I really like the MDX and we really considered one for my wife back in '18 before we bought her Grand Cherokee.
That's my thoughts. That and a quarter will get you.....well, I guess nothing anymore.
And for the wife, I wouldn't overlook something like a Honda Pilot, Acura MDX, or a Mazda CX70 (or CX90). They all have higher trims that are very nice. I really like the MDX and we really considered one for my wife back in '18 before we bought her Grand Cherokee.
That's my thoughts. That and a quarter will get you.....well, I guess nothing anymore.
Good advice. However, never say never but I’m not selling the Mustang. WAY too much fun to drive. Just needs gears. The tow rig, we shall see. I bought it new in ‘08. Its been OK. I won’t bore you details, but I’m running out of patience. You are right on cost. A new replacement will be minimum 2x what I paid for it. The GMC needs a front straight axle conversion and a new wiring harness. Maybe new tow rig and old tow rig becomes the fire truck? My wife’s car is the issue. She’s happy with what she has but at 160K, it’s a ticking bomb. We both agree the current germans aren’t worth the money and she says she would be happy with the CRV if the truck needs replacement. We had a ‘02 CRV before her ‘13 X3. Then, as now, the CRV was a good value. I also like the Acuras. We need to drive a Volvo. Both are more reasonably priced. So we’ll see.
Get a water trailer...makes tow rig a fire truck...or even the Jeep...
-Mac
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