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Rear timing tensioner trouble 2003x

prodigy9904

Member
Joined
January 7, 2011
Messages
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City, State
Walla Walla, WA
Year, Model & Trim Level
2003 XLT
Decided to change out my tensioner to avoid future problems. Background 2003 X 137k slight rattle at cold startup from passenger side rear tensioner goes away within a second also was having slight timing issue. Bought ac delco tensioner and installed it, problem fixed at startup, but now it ticks when it warms up???? I installed a preferred components front tensioner and X sounds like a diesel, I can't win for thinking ahead. I reinstalled factory tensioner in front noise gone, but still ticking from the rear after motor is warm.... Help
 






I am wondering if you have the good ol' 4.0 SOHC engine? If so, it is most likely more serious such as the internal mechanical tensioners for the timing chains starting to have issues. I have had several of these gone bad and all of them had different noises attributed to them until they got very bad. All 6 engines (when torn apart) had broken pieces of wear guides all over. All of these engines still ran when torn apart and some were ticking and rattling very loud and a few others were just having small ticking noises. If just changing the oil tensioners on the sides of the block made your noise change then it would be a good indication that the internal chains and tensioners were the actual issue. I had purchased some Cloyes after market oil tnsioners for one of my "tickers" and tried to install them. The Cloyes tensioners had much greater spring pressure than the Ford stock ones I took out. The added pressure on the already damaged wear guides made the sound change as well as got worse. Let me know what engine you have in yours...
 






Engine 4.0, I bought the X new DEC 2003 the coder reads it as a 2004. Any way prior to changing the rear tensioner the rattle that was there lasted literally 1 second and then gone maybe 2-3 seconds in the winter. Now at cold startup no rattle, but after reaching temperature it starts ticking from the rear of the motor. When I changed the front tensioner it created a large noise. I have determined a flaw in oil port position placement on new tensioner causing there to be no oil pressure in the tensioner. I reinstalled factory tensioner noise gone operating normally. I also think the new rear tensioner is having oil pressure issues. The factory rear tensioner had a weak spring but gained good oil pressure to do it's job after a cold start. The new tensioner has a strong spring but weak oil pressure to deal with the chain lengthening after warm up allowing play and a ticking noise. I think I'm going to get genuine Ford parts and return these.
 






Food For Thought

The degree of the drilled oil hole in the tensioners compared to the degree indexing of the factory part oil hole drilling should still deliver oil just fine considering that no matter where the placement of the hole around the tensioner, it still falls within the recessed oil groove cut into the tensioner bore. Remember that the side of the chain that is against the tensioner has absolutely no tension on it from the cam. It is the "slack" side of the chain and actually takes very little pressure to keep the slap and slack out of the chain when running or sitting still. Any noise at all always makes me suspicious especially when the noise is increased for duration when warm. Remember, when things get warm, steel gets larger by a few thousandths of an inch. Things such as lifter or valve guide tick or even forged piston skirt tick would be heard louder and longer when cold until the metal grows a bit from the heat of the engine and takes up some of the space in the different guides and bores etc... Things that are not bore related such as the timing chains will get larger too meaning they get longer and looser. Worn guides and stretched chains can have a longer duration of noise when already warm.

Here is a picture of one of the timing chain cassette tensioners from a 4.0 I took apart today that just needed a valve cover gasket. This engine ran good and had just a very small tick when started.

20140715_223840_zps6c8ac115.jpg


I would take an hour of time and take the valve covers off so you can look down the timing chain holes and inspect the parts as best as you can. While you have the covers off you will also be able to look and see of there is the rare possibility that their is a lifter or arm that has a pin coming out. I would NOT just start buying parts and trying to replace things until you find the culprit. I feel like the bearer of bad news and such a "joy killer" but I have yet to tear apart one of these 4.0 SOHC's with over 50,000K on it and find all the timing tensioners in tact. The good thing is that they will run and run and run until they damn near fall apart by themselves with bad chains... LOL:salute:

FYI: If you are looking at the RH side (passenger) that has the chain near the firewall, I have used my cell phone and turned on the flash and took a close up movie of the tensioners and chain because I could not get my head back close enough to see. If you get some good pictures and questions, post them and I'll do my very best to help out.:usa:
 






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