So, a few years back I had John from ICES Performance replace the engine/gearbox/fuel system in my 2002 Cobra with a lightly used 2003 setup. While it's supercharged the design of the motor is very similar to the 2000/1/2 engines, it just uses a few different components. I had about 170K on the old drivetrain as I drove it every day from new and pushed it pretty hard, and it mechanically was faultless. The new setup now has about 60K on it.
Over the past few years I've noticed an annoying issue with the 2003 motor in my 2002 Cobra - about 2/3 time at startup from cold there is a 'rattle rattle' or 'tap tap tap' coming from the front driver's side of the motor for a few seconds (at first anyway, after a year or so it was 20+ seconds...).
I wasn't sure what it was but wondered if it was the lifters, a cam follower, exhaust leak, cam guides, cam chain tensioners etc. This noise would come back at idle when the engine was very hot on a hot day - when the oil had thinned out and the oil pressure was dropping..
So, tried the headers - all good, no leaks. Replaced the lifters and a little better. So, as I'm up to my nuts in investment in this car, it seemed prudent to find the cause and fix it. So, a buddy is a Holden mechanic and we'd discussed this a lot, and he agreed to pull it down and find the cause.
So, off with the all the bolt-ons and start checking stuff. There were a few cam followers that exhibited more play than the others, which would contribute to a generally noisy engine, so they've been replaced by cam followers from a 5.4 modular motor (similar but improved design). Pulled down the front of the motor and found 2 of the 4 cam chain tensioners had blown out the seal on the back of them. This is a known cause of these issues, and eventually the lack of pressure at start-up will break the top off the cam chain guide and then shit starts moving around.
Here's some pics:
So, I thought so long as the thing is apart, might as well replace everything - cam chains, tensioners, guides (new improved design that doesn't break), sprockets, oil pump - that could conceivably go wrong, and luckily there's a kit for that:
https://performanceparts.ford.com/part/M-6004-A464Oil pump:
https://performanceparts.ford.com/part/M-6600-D46Gasket set
https://www.modmaxracing.com/03-04-COBRA-4V-4-6-Complete-Gasket-Kit-p/felfs26187pt.htmSo, car is due back soon and I'm expecting the engine to be as quiet as a grave (even if the exhaust isn't) and run like a top.
The replacement tensioners do not have the little rubber seal on the back that bleeds off oil pressure when the motor is off, they're an improved design that seals to the machined surface of the block.
Cheers
