UnfrozenCaveman
Explorer
Very interesting project. For sound insulation peek at ne of the UK Rover magazines at your local Barnes & Noble. Those guys use blankets that tie onto the engine?!
1999 Jeep Wrangler 2.2L Kubota diesel swap
- Thread starter redveloce
- Start date
Brandon Libby
GeeK
Dynamat makes a heat insulation/dampening Hood Liner.
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I've never been able to wrap my head around the price of dynamat, but that may be the ticket if I end up needing it. I was playing around on the way to work and observing the resonance effects of different RPMs (as opposed to sitting at my desk at work and trying to remember), and I think I may have been wrong about the hood being an issue. It doesn't move nearly as much as I remembered, and I think the rubber bumpers for folding the windshield do a good amount of vibration dampening.
The main areas of resonance seem to be the doors (makes sense since they're flat sided boxes), tailgate, and body sides. I'll probably start with those, and after it's warmed up and easier to work with I'll probably cover most of the floor and firewall as well. It's never going to be a Cadillac, but it's a relatively simple job and I'll have the material, so I may as well do what I can. Just doing the worst offending areas should make it quieter than it was stock.
jeepdreamer
Expedition Leader
Here is an alternate idea for you? 
http://www.jegs.com/p/Lizard-Skin/L...und-Dampener-and-Accessories/1122693/10002/-1
http://www.jegs.com/p/Lizard-Skin/L...und-Dampener-and-Accessories/1122693/10002/-1
I spent the weekend working on a few different things.
I installed sound deadening material in the doors, body sides, rear fenderwells, and rear deck area. It seems to work pretty well, but I still have to do the front and rear footwells.
The water/methanol injection has been offline since the first trip over the pass, because the nozzle was way too large, and it was quenching the combustion as I backed out of the throttle. I ordered a smaller nozzle last week, and it showed up in the mail on Friday. Wow, it makes a huge difference! It basically makes hills feel like flat ground. It also helps during hard acceleration, but the engine pulls so quickly through the RPM band there normally anyway that the difference isn't as noticeable. I'm using straight Peak brand -20 washer fluid, but it appears to contain too much methanol to get a cooling effect. M/W injection is often used to bring down exhaust gas temps, but I'm not seeing that benefit. The EGTs rise considerably faster when the m/w is kicked in, but so far they've seem to flatten out at 1100 degrees. I'm going to try diluting the mixture with some water after I run the tank down a bit to see how much difference that makes.
It did take some tuning to get it to kick in at the right time. I installed an LED in my dash to indicate when the system is engaged, and it was originally set to 10PSI. I wanted it to kick on sooner, so I adjusted the boost switch in increments. The sweet spot seems to be 6PSI. Most of my easy driving around stays under 5PSI, and it gives me an instant boost if I jump on the throttle. Any less than that, and it is coming on at smaller throttle openings, and it quenches the combustion, making it cut out and miss. I've still encountered that with the current settings in one scenario, backing off the throttle while pulling a long grade, so I've ordered a pull spring microswitch that I'll wire up to only allow the system to engage at larger throttle openings.
I installed sound deadening material in the doors, body sides, rear fenderwells, and rear deck area. It seems to work pretty well, but I still have to do the front and rear footwells.
The water/methanol injection has been offline since the first trip over the pass, because the nozzle was way too large, and it was quenching the combustion as I backed out of the throttle. I ordered a smaller nozzle last week, and it showed up in the mail on Friday. Wow, it makes a huge difference! It basically makes hills feel like flat ground. It also helps during hard acceleration, but the engine pulls so quickly through the RPM band there normally anyway that the difference isn't as noticeable. I'm using straight Peak brand -20 washer fluid, but it appears to contain too much methanol to get a cooling effect. M/W injection is often used to bring down exhaust gas temps, but I'm not seeing that benefit. The EGTs rise considerably faster when the m/w is kicked in, but so far they've seem to flatten out at 1100 degrees. I'm going to try diluting the mixture with some water after I run the tank down a bit to see how much difference that makes.
It did take some tuning to get it to kick in at the right time. I installed an LED in my dash to indicate when the system is engaged, and it was originally set to 10PSI. I wanted it to kick on sooner, so I adjusted the boost switch in increments. The sweet spot seems to be 6PSI. Most of my easy driving around stays under 5PSI, and it gives me an instant boost if I jump on the throttle. Any less than that, and it is coming on at smaller throttle openings, and it quenches the combustion, making it cut out and miss. I've still encountered that with the current settings in one scenario, backing off the throttle while pulling a long grade, so I've ordered a pull spring microswitch that I'll wire up to only allow the system to engage at larger throttle openings.
Brandon Libby
GeeK
Just out of curiosity, have you considered experimenting with different mounting materials for the engine and transmission? I'm sure there are plenty of affordable factory rubber or hydraulic mounts out there -though hydraulic may not be practical for off road use. Some quality mounts could also reduce the chance of cracking welds and other wear.
Vibration isn't an issue. The factory mounts are very effective at absorbing the vibration, but there will always be some that gets through. It was just the large flat single wall metal panels reverberating at certain frequencies. The doors are very effective drums without the dampening material.
jeffjeeptj
Adventurer
As far as underhood, have you thought about a factory hood insulator from a LJ? It has some type of fasteners to hold it in place. Much quieter than my 2002 TJ.
Hmm, I wasn't aware that LJs had underhood insulation. I don't think there is an issue from underhood noise, but if I can find a good deal on one (nearly free) I'll see how it works!
Those are pretty nice mounts! People seem to like the hydraulic engine mounts that Ford used with the 300 6 cylinders in the 90's (maybe earlier too, I'm not sure), and they're a somewhat similar idea.
Engine vibration isn't an issue with my Jeep though. I reused the factory Jeep mounts, which are very thick and soft rubber. I have far less vibration than my father's '00 Dodge with a Cummins. I added sound deadening material to the doors, tub sides, and rear deck last weekend, and the drone is completely gone. It's quieter now than it was with the 6 cylinder. The issue was that different engines configurations have different resonant frequencies. When a manufacturer is testing a vehicle design, they go through and address undesirable noises and such produced by the current configuration of the vehicle. One example of this on the Jeep are several plastic dash panels that have stick on felt added where they meet. There are many panels that don't have felt, and the reason is that they only added the material where the resonant frequencies of the factory 4 or 6 cylinders would cause panels to vibrate against each other. Since I re-powered the Jeep with an engine that the factory never intended, I basically have to do all of the 'test mule' refinement on the configuration myself.
I also have a bad transmission mount that I'm sure contributed a lot to the frequency transmission. It was bad for a while before I did the engine swap, but I've been putting off replacing it because other parts of the project have been much higher priority, and it hasn't affected driveability before now. The movement from the bad mount caused one of my exhaust brackets to break last weekend though, so I've ordered a new mount and will replace it as soon as it arrives. Pretty silly to put off what is basically a 15 minute job, but time is time...
Thanks! Have him send me a message if he has any questions about the swap whatsoever! In addition to the mechanical and fabrication aspect, I have learned a LOT about how the electronics in the Jeep function and interact.
Just found this thread... great swap... as an engineer that also has a machine shop out back I find that what your friend did was outstanding... I have thought of building soemthing like this but not ready to just yet... want to keep track of the progress and hope all will be well with it...
mogwildRW1
Adventurer
Geez, who let the tool bag out?
goin camping
Explorer
Why the hostility?