RE: Timing belt replacement and tensioners.
Login  | |
|
RE: Timing belt replacement and tensioners. - 11/7/2006 10:31:52 PM
|
|
|
Manybrews
Posts: 774
Joined: 5/23/2003
From: United States
Status: offline
|
its not necessary to replace the tensioner, pulleys, or water pump during every timing belt change. In fact, its rare on a mitsu to need ANY of those, with a few notable exceptions.
the older monteros with the DOHC 3.5 liter (last used in 96, I think) ate water pumps. i havent needed to replace one on any montero since the demise of that engine, and Ive seen them at 197K.
the pulleys? one in a million chance of failure, regardless of engine. And the tensioner? Occasional failures, but its usually noticed after it totally fails as the noise it creates is loud.
also, the timing belts are not needed every 60k on the V6 engines. 100k is much more sensible.
|
|
|
|
|
|
|
RE: Timing belt replacement and tensioners. - 11/7/2006 10:51:45 PM
|
|
|
off roader
Posts: 419
Joined: 10/20/2005
Status: offline
|
quote:
ORIGINAL: Manybrews
its not necessary to replace the tensioner, pulleys, or water pump during every timing belt change. In fact, its rare on a mitsu to need ANY of those, with a few notable exceptions.
Don't missunderstand me... not saying it's got to be done... I'm saying doing it every 60k or even 100k is cheap insurance.
Also, they DEFINITELY wear out. Mine on my 1990 3.0L v6 w/ +120k since the last change is sqealing like a stuck pig now. I didn't get to do it the last time due to lack of availability.
|
|
|
|
|
RE: Timing belt replacement and tensioners. - 11/10/2006 2:43:37 PM
|
|
|
Winshawn
Posts: 269
Joined: 1/31/2005
Status: offline
|
TJ,
I dont want to scare you but;
The little tensioner pulley has two holes about 3/4 in apart. Those holes are used to apply torque to the pulley which tensions the timing belt. Then you remove the little pin/nail holding the hydraulic tensioner compressed. The little piston on the tensioner should not move. In fact you should rotate the engine through two complete revolutions, then check to see if you can reinsert your pin/nail into the tensioner. This torquing of the tensioner pulley is necessary to allow the hydraulic tensioner to have movement to make up for the stretch of the timing belt as it ages. If you did not properly torque the pulley with the two little holes, your timing belt will become loose prematurely.
TJ, did you check the movement of the tensioner after you removed the little pin?
Manybrews,
It is nice to hear your opinion of failure rates of water pumps and pulley bearings. I too, have only heard of failures of water pumps on DOHC engines. However, my experience is clearly limited. I am trying to decide what to change on my 167k engine, and since it is an older vehicle I don't want to sped too much on it.
< Message edited by Winshawn -- 11/10/2006 2:46:03 PM >
_____________________________
'90 Montero (sold-sadly)
'95 Montero LS (166k) - my car
'03 Montero Limited (36k) - wife's car
|
|
|
|
|
RE: Timing belt replacement and tensioners. - 11/10/2006 4:55:10 PM
|
|
|
tj90
Posts: 150
Joined: 9/15/2006
Status: offline
|
Thanks for the follow-up. I had trouble getting the new belt on because I fought the plunger on the tensioner pulley. I did not know about the pins that keep the tensioner compressed (that would have made the job much easier). Anyway I torqued everything to specs in the mitsu manual and rotated the motor a few revolutions to make sure everything was working properly. It is one tough ass spring on the tensioner pulley). Anyway, it is something that I will be monitoring for the next few 10k miles. Luckily, mitsu put the access hole in behind the fan pulley so you can check the tensioner. In fact, I will be checking it this weekend since its been a month. Probably a good idea to check every 10-20k miles since its such a critical component and does not take much work to check....
|
|
|
|
|
RE: Timing belt replacement and tensioners. - 11/11/2006 9:09:09 PM
|
|
|
tj90
Posts: 150
Joined: 9/15/2006
Status: offline
|
OK - I checked the timing belt. Still under good tension after 1k miles. I will check again in another 7k miles. For those that are curious how to check the tension of your belt on a GENIII, Mitsu engineers clevery designed an access hole that sits behind the fan pulley. First remove the air intake, upper fan shroud ring. Loosen 4 bolts that hold on fan to pulley (dont remove serpentine belt yet, using the belt to hold freewheeling fan hub). A breaker bar is useful to loosen sepentine belt when you want to move hub easily as well. Once fan is out, remove serpentine belt and remove outer pulley. Then remove the 4 14mm bolts to expose timing belt access hole. You cant really inspect the belt well, but you can jamb a finger in there to feel the tension on the belt. I checked and reassmebled in about 45 min taking my time.
AGAIN, MY ORIGINAL BELT AT 60K miles WAS LOOSE. After seeing that, I will add this to routine maintenance every 10-15k miles. It was only a matter of time before my belt jumped cogs or broke due to excessive wear cause of the slop.
The first pic is of the access hole (red arrow) after the fan pulley was removed. The second pic is of the timing belt (what I could capture at the wierd angle) visible at the access hole.
Thumbnail Image
Thumbnail Image
 Attachment (2)
< Message edited by tj90 -- 11/11/2006 9:16:40 PM >
|
|
|
|
|
Printable Version
