Quinnchuck
Getting the Wheeling Fever
Reged: 04/19/05
Posts: 95
Loc: Loon Lake,B.C.,CANADA
|
|
With the 2.6 rebuilt now & the balance shafts eliminated,& an E-kit installed in its place. I know from installing two of these kits before there was some vibration mostly at idle & seemed not to bad at higher speeds.I find it at higher speeds & all through the gears.  I'm wondering if the motor mounts would have enything to do with transfering more VIBRATION threw if the passenger side mount would be out of alignment ,or bent ? Your input would be great  [image] [/image]
--------------------
"YOU CAN ONLY LEARN SO MUCH KNOWLEDGE IN A LIFETIME..BUT IMAGINATION IS WHAT MAKES THE WORLD GO AROUND"
89 POWER RAM D50 4X4 XCab 2.6L
91 Grand Prix GTP 3.4L
87 Jeep YJ Laredo 4.0L EFI
|
powerRam50
Body Damage is Cool
Reged: 01/15/03
Posts: 1726
Loc: springfield,oregon
|
|
that motor is cleaner than my darn kitchen 
--------------------
87 dodge power ram 50,35" tires,5 1/2" total lift,4.6 gears,lockers front and rear,Rancho RS5000's,custom front bumper,custom rock sliders,cct extended diff breathers,75 amp alt(40 amp stock),thorely header,K&N,wheeled hard...
|
weebur
Wheeler
Reged: 12/05/02
Posts: 120
Loc: Algonquin, Illinois
|
|
In one of Fasteddy's recent posts he says he broke several mounts after installing the BSE kit. I did mine last week and my rig sounds like it's going to fall apart. I've got things vibrating that I didn't even know I had. I'm going to spend a day tightening up everything I can find, including the motor mounts, you might do the same.
Great looking engine...I bet you just stand around looking at it.
--------------------
'97 Jeep Cherokee XJ, Country, Black/Gray Leather, 4.0L, 4WD Command-Track, AW-4 Auto, 3.55:1 Gears, PowerTrax No-Slip Locker, Hi Country Tow Brackets, Spectre Air Filter, 235X75R15 Goodyear Wranglers, 126K miles
|
Quinnchuck
Getting the Wheeling Fever
Reged: 04/19/05
Posts: 95
Loc: Loon Lake,B.C.,CANADA
|
|
Awww tank U vedy much grasshoppers  for the great reply on the shiny new motor.Yes...yes I did stand around & drooled on it, untill I saw the antifreeze sweating out of the side of the block  I could of almost cryed when I saw that  .There was 2 cracks in the block between the two frost plugs under the exhaust side.Luckily the very reputable machine shop where I had the block done said they would & could fix it by stitching it  .Got it back today. They admitted they did not magniflux the block assuming that it was good already.
If it ain't going to go fast,might as well make it look like it does
--------------------
"YOU CAN ONLY LEARN SO MUCH KNOWLEDGE IN A LIFETIME..BUT IMAGINATION IS WHAT MAKES THE WORLD GO AROUND"
89 POWER RAM D50 4X4 XCab 2.6L
91 Grand Prix GTP 3.4L
87 Jeep YJ Laredo 4.0L EFI
|
toddstidham1
Mudrunner
Reged: 02/01/07
Posts: 479
Loc: Philadelphia Area, PA
|
|
I've done quite a few 2.6L with a BSE kit installed, but we always weight balanced the pistons and rods before assembly. Never heard anyone complain about the motors vibrating though.
--------------------
-Todd
1987 Montero 2.6l 5-speed (Sold...but I still miss her)
2008 Jeep Patriot Sport 4x4
|
Kevin C
Trail Leader
Reged: 05/20/00
Posts: 6033
Loc: No where in particular
|
|
I found that new mounts had a bit more give to them and helped isolate the motor better, not a cure all but it may help.
Some vehicles without balance shafts use silicone filled mounts with internal chambers to further isolate the motor. On these same engines they design them so that the resonant frequency of the parts bolted onto the motor ( intake manifold, alternator etc) is higher than the second order vibration from the uneven piston acceleration all engines have. This prevents the parts from singing along.
Pistons accelerate faster off of TDC than BDC since we don’t have the luxury of infinitely long connecting rods--- an unequal acceleration exists between each pair of pistons as the motor hits TDC / BDC.
Longer stroke motors can’t grow the rod length enough to keep the vibration reasonable, hence the need for balance shafts on motors like the 2.6.
Balancing the pistons, rods and crank does not get rid of the basic problem. It can eliminate first order vibrations and even out the magnitude of the second order vibration so that each second order vibration is that same as the other but it cannot get rid of it, just even out the size of the pulse from piston set to piston set ( two pistons up VS two pistons down, they travel in pairs on a 4 cyl).
The only way to reduce the size of the vibration is to lower the weight of the pistons, reduce the weight of the rods or use longer connecting rods.
As you get a few miles on the motor it will smooth out at idle bit as the friction level drops. High friction slows the motor more between firing pulses adding to the shake at idle.
At higher RPM's the motors without balance shafts will make more noise since the vibrations are not canceled internally. When the frequency of the vibration is the same as the natural frequency of any component on the motor that part will vibrate in unison, just like a tuning fork ( a harmonic of the frequency will do the same thing but at a lower amplitude).
I stand by claim that the main difference is some people just don’t notice the difference. Kind of like how some people can drive a car around with a low tire and one broken shock and not notice.
Kevin
--------------------
87 Dodge
Edited by Kevin C (11/03/07 11:52 AM)
|
toddstidham1
Mudrunner
Reged: 02/01/07
Posts: 479
Loc: Philadelphia Area, PA
|
|
Quote:
Kind of like how some people can drive a car around with a low tire and one broken shock and not notice.
This is very true! LOL.
On vibration thing, well written explanation. Now that I'm thinking about it, all the motors we did were for minivans and front wheel drive chryslers, so I wonder if the transverse mounting alters the sense of the vibration as well (front to back rather the side to side)? Perhaps front to back is less annoying to the senses?
--------------------
-Todd
1987 Montero 2.6l 5-speed (Sold...but I still miss her)
2008 Jeep Patriot Sport 4x4
|
Kevin C
Trail Leader
Reged: 05/20/00
Posts: 6033
Loc: No where in particular
|
|
Quote:
Quote:
Kind of like how some people can drive a car around with a low tire and one broken shock and not notice.
This is very true! LOL.
On vibration thing, well written explanation. Now that I'm thinking about it, all the motors we did were for minivans and front wheel drive chryslers, so I wonder if the transverse mounting alters the sense of the vibration as well (front to back rather the side to side)? Perhaps front to back is less annoying to the senses?
Absolutly...
The engine rebuilders that were doing ballance shaft eliminations almost never had a complaint on the FWD's. From what I read its was the RWD models that customers noticed the differance on.
Kevin
--------------------
87 Dodge
|
powerRam50
Body Damage is Cool
Reged: 01/15/03
Posts: 1726
Loc: springfield,oregon
|
|
man i have never broke anything on my truck from vibration.and it does not seem bad at all.i have had v8's that vibrate more than my truck and my wifes.i am glad that i have been lucky.
--------------------
87 dodge power ram 50,35" tires,5 1/2" total lift,4.6 gears,lockers front and rear,Rancho RS5000's,custom front bumper,custom rock sliders,cct extended diff breathers,75 amp alt(40 amp stock),thorely header,K&N,wheeled hard...
|
Quinnchuck
Getting the Wheeling Fever
Reged: 04/19/05
Posts: 95
Loc: Loon Lake,B.C.,CANADA
|
|
I guess with the motor's being actually a(big 4 cyl.)2.6 ,it is a good point on the internals being the problem ,on the balance part, also being a tighter (rebuilt )could have lots to do with it. I'll check the mounts & maybe even the trans mount.It just dosn't feel right compared to the other 2 motors I had with the E-kit in it.
--------------------
"YOU CAN ONLY LEARN SO MUCH KNOWLEDGE IN A LIFETIME..BUT IMAGINATION IS WHAT MAKES THE WORLD GO AROUND"
89 POWER RAM D50 4X4 XCab 2.6L
91 Grand Prix GTP 3.4L
87 Jeep YJ Laredo 4.0L EFI
|
Previous
Index
Next
Threaded
Edit
Reply
Quote
