As stated, my 4ac knocks on start up.

 

It is a top end knock and is coming from the 4th cylinder only, sometimes the noise lasts a few seconds and other times 10 or 20 seconds. I would say it has to do with oil circulation as it only really happens when the car is cold. I also think it is linked to the cold weather and thickness of oil. The car is running 20w50. The last oil which come out of the engine was in a rather bad condition. Is this a common thing for 4ac's, not much out there about the issue.

 

Any help is appreciated, thanks

Cam followers in the tappets. Id say one has ʞ©$ɟed out. The are hydraulic lifters.

thanks, ill have a look into that

so i took the rocker cover off today and discovered that the cam drive gear has chipped and damaged teeth. Anyone know how much a mechanic will charge to fix this, really don't want to be spending too much money on a 4ac. On the plus side, everything else looks pretty good, tappets could use adjusting. Here are a couple of pics, Need some opinions

 

 

 

Edited April 14, 201313 yr by Willacy70

That is nasty!!

 

well if you got that far yourself, then you can do the rest!

 

grab another cam and chuck it in, do your tappets and your done.

 

most people can't give away 4ac's so if you can get a complete motor to steal the cam from you should get it fixed for a hundred bucks or less.

I've had this happen before, the distributor shaft seized up & as it's driven off the camshaft, it got messy. Shattered gear teeth & distorted the camshaft (which I've since made into a lamp), my mechanic charged me just over $300 for repairs. Bear in mind that was over 5 years ago & I was on "good terms" with my mechanic, so it will be far cheaper to repair this yourself especially since you've made it this far. :y:

That is nasty!!

 

well if you got that far yourself, then you can do the rest!

 

grab another cam and chuck it in, do your tappets and your done.

 

most people can't give away 4ac's so if you can get a complete motor to steal the cam from you should get it fixed for a hundred bucks or less.

I've had this happen before, the distributor shaft seized up & as it's driven off the camshaft, it got messy. Shattered gear teeth & distorted the camshaft (which I've since made into a lamp), my mechanic charged me just over $300 for repairs. Bear in mind that was over 5 years ago & I was on "good terms" with my mechanic, so it will be far cheaper to repair this yourself especially since you've made it this far. :y:

 

thanks for the help guys. Not really sure what to do,might drop it off at a mechanic tomorrow and see what they say. Surprisingly the car still runs fine but with the knowledge there is a tooth from that gear floating around somewhere i don't really want to take any chances driving it around.

Edited April 14, 201313 yr by Willacy70

Just had a closer look at the gears on both the cam and distributor and both seem to be damaged but there is no sign of the tooth that has chipped off. I would assume then that this damage has happened previous to me owning the car (owned for 7 months) and has been getting increasingly worse. Does this sound right? Sorry for all the questions, I'm only fairly new to the whole home mechanic thing. Like always, any help is appreciated

Can i say that the chipped gear pueces are somewhere down in the oil pan? I can only imagin it sinking down but who knows what else it may have crunched up along the way. The cam gear shouldnt be too hard to change given most cam gears have very few bolts. It's not hard to figure out. Just take a look to the side of the cam, get tool, switch it out and bam, its done! (make sure your timing is right though lol.

...look to the side of the cam, get tool, switch it out and bam, its done! (make sure your timing is right though lol.

 

*wizz*pop*bang* TADDAAAA!!!

If you ever feel brave enough with your mechanical skills try to remove the oil pan after draining the oil to see if you can find any remnants of the pieces and remove them with a strong magnet (its better than using fingers and well pick up more). Don't wanna risk it getting picked up back into circulation from the oil flow.

yeah its probably fairly safe to say the bits of gear are in your sump somewhere....

 

The oil strainer should have kept most of them out of your engine.