Timing Chain Jumped

[Nomis]

I haven't had any experience yet but they are all in my built motor(not running yet) but yeah it was brad from atomiks idea I had no idea these failed but he said he has seen it more and more and it's pretty cheap for piece of mind!

[JGP]

cheers,

did he mention any replacements for the plastic chain guide? mine snapped probably living in the oil sump now!

[Nomis]

Nah not at all that would only snap if something else failed wouldn't it??

[ratter]

The problem is not the chain but the guide, the plastic breaks and falls into the crank gear which causes the chain to jump, have seen it possibly eight times now.

Atomic use the factory guides as there is no other option at present.

Apparantly there was an update in late BF, but I have seen BA, BF's and 2 FG's with broken guides

Edited 25/10/11 09:49 AM by ratter

[JGP]

cheers,

and once again would like to say thanks for the hard work and extra hours!

[Barnesy]

Mick (Pit Lane Performance) rebuilt the top end of my car when it snapped the plastic timing chain guide and bend all the intake valves. Its an expensive exercise so get it fixed asap.

[sexual harrassment panda]

surely someone cound know up a replacement one out of somethis that would last a bit more.

Any pics of this plastic part?

[JGP]

Nah, I told Mick to keep it on display along with the FG broken one!! Maybe send them to Ford engineering? Do all DOHC engines have plastic guides?

[blueprintbullet]

yep same thing happened to me on my fg ute. Strange thing was it was the week after my gearbox failed, they asked me if id had it on the dyno and I told them to check it themself she's stock as. Fortunatly no damage occured and they were able to fix it within the week but it left a real sour taste in my mouth.

[45T-XR]

How many k's did your car have on it, I have seen standard cars do it also, but not to the extent of 3 teeth out or not a I6 engine anyway.One thing I dont know is If there are a free-spinning head assy, ratter might be able to verify that one but I havent seen too many engine running a timing chain that are actually free spinning. As sometimes jumping a one or several teeth can cause it to run like sh*t but otherwise cause little or no damage. If the timing chain were to fail, that would be a different story.

Also at what km service interval has your car been serviced, although it is problem occuring more commonly, Im wondering If a relatively large amount of kms between oil changes would contribute to the failure, as in having fairly contaminated/burnt oil could contribute to the deterioration of the plastic timing chain guides.. Just a though. I know plastic probably isnt the most durable material either. In the early BA quad cam motors we had dramas with the standard timing chain tensioners as they were plastic with a oring seal incorporated into then, they used to get a bad timing chain rattle on start up as the orings used to fail and leak oil pressure, releasing the tension off the chain, the rattle would stop usually as engine oil pressure built up. The revised timing chain tensioners were steel, but I cant remember if they had a gasket or if they were a metal/metal seal. As the mating face of the steel tensioners were highly polished from memory. I cant remember if the I6 kept the plastic tensioner or if they went to a steel one also, Its been years since I had one apart. Guess I will find out when I build mine. Generally you dont have to pull the timing cover to check the timing. The chain has 3 yellow links from memory, used to set the timing when it goes together. Now the links move around as the motor turns but the links line up with their corresponding marks on the cam/crank gears every 34 or 37 engine revolutions, (my apologies its been way too long since I worked there) Its another handy way to double/triple check your handy work. I used to be a bit paranoid though when I was working on customer cars. I will try go back through my apprenticeship literature and confirm the number of engine revs