Kia Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
Hi all. I recently purchased a used Sorento with 146,000 miles on it. I will not drive this vehicle until I determine the condition of the timeing belt and all associated parts. I removed the upper left belt cover and rotated the engine by hand while looking at the belt. The belt looks very good. I am thinking it was probably replaced at or near the 120k point. That doesn't of course tell me if the other items were. So I will probably take the rest of the covers off and take a look see. One thing I did notice was that if the engine is rotated in the wrong direction just a few degrees a fair amount of slack is created in the belt between the left bank cams and where the belt drops down to the water pump pulley. Is this normal? Timming belts on other cars that I have replaced to not do this. I suppose that the extra pressure placed on the tensioner would produce slack in another part of the belt. Any thoughts?
 

·
Registered
2009 Sportage, 98 Sportage, 2012 Tata Xenon, 1944 Jeep
Joined
·
515 Posts
Remember that it is actually the (fairly small) crank cog that drives the rest of the system, this cog is designed to drive with tension on the leading edge, and that is where the tension in the system is. In the Kia V6 the belt has to drive four cams and the waterpump so the belt is kept fairly tight. The other "tensioner" is in fact really just an idler, which feeds the belt back to the crank and enables it to get a fair "wrap" of the cog. If you turn it backwards it is trying to drive the belt from the slack side and hence you will see the bunching up effect. I do not advise doing this as it is easy to push the belt off the pulley and possibly jump a tooth.

Most Gilmer belt timing systems are like this more or less, in some the belt will actually come off if you turn them backwards.
 

·
Registered
Joined
·
2 Posts
Discussion Starter #3
Thank you for your response. That is a bit freightening though. So what you are saying is if the engine is reverse rotated it might slip a cog. It is a standard transmission. I am sure I have on occasion mistakenly left a standard trans car in a forward gear and rolled it backward on a incline and released the clutch. That leaves open the posibility of slipping the timming and ruining an engine in the case of an interference engine. not a good design is it?
 

·
Registered
2009 Sportage, 98 Sportage, 2012 Tata Xenon, 1944 Jeep
Joined
·
515 Posts
I don't know if it possible for it to slip enough teeth to actually get the timing out far enough to hit a valve, however I HAVE heard of manual Mitsubishi Pajero's (same engine) which have stalled on a very steep climb off road, and rolled back a compression or two when the engine was off. When they were started the owners commented on a rough idle and tendancy to stall. This was later traced to a slipped belt being a tooth out. So it CAN happen. Yes it makes me glad to think mine is an auto.

The car I was thinking of where the belt can come off was the old Ford Pinto / Cortina / Escort , 2 litre OHC four from the 1970's early 80's. Ford were an early adopter of the timing belt system, ufortunately the art of making timing belts was not quite perfected in the 1970's and they needed fairly frequent replacement, inspection, if you inadvertantly turned the 2 litre backwards it almost always slipped the belt.
 
1 - 4 of 4 Posts
Top