Jump to content

Zetec supersport issues...


zuspiel

Recommended Posts

Hoefi is correct....the stock Zetec oil pump gears are made out of powdered metal and can shatter. My experience with Miata engines this usually only happened if someone used an aluminum underdrive pulley on the front of the crank instead of the stock damper....creating a resonance at high RPM that the nose of crank transferred to the oil pump gears.

 

The billet gears are very good insurance for higher RPM Zetecs They are sold by a couple people but Central Florida Motorsports is where they all come through as far as I know. I have used a couple sets and just ordered some more...

Link to comment
Share on other sites

Its pretty easy to install the gears if you have the oil pump in your hand. Not so easy to get the oil pump in your hand. I wouldn't worry about doing it unless you doing something else where you have the engine out. Where you have the rev limiter set now is plenty safe. I don't know who built these Supersport engines....there might have been an alternate solution installed when they were put together.

Link to comment
Share on other sites

Its pretty easy to install the gears if you have the oil pump in your hand. Not so easy to get the oil pump in your hand.

 

;) Like many other jobs...

 

I'll try to find out and put this on my list of things to do if the engine ever comes out. Thanks!

Link to comment
Share on other sites

Zetec motors has a documented problem with the stock oil pump gear blowing up at 7400+ rpm. Most Focus owners with high output engines know about it. There is a steel oil pump gear upgrade from most Focus hp shops. Without this upgrade, most focus owners will set the rev limiter to 7200.

 

Thanks, I didn't know. Jon @ Caterham who built this motor told me 8K is fine. I wonder if he installed upgraded gears in the oil pump. I would ask him but he told me before it was so long ago he built the motor (2004) he doesn't remember what's in it. Is the oil pump gears on the front of the crank or in the crankcase driven off the cam. I've never taken apart a Zetec or Duratec, only GM and Ford small blocks, or Pontiacs.

Link to comment
Share on other sites

I have never had anyone in the Focus community admit it, but I do think the the aluminum crank underdrive pulleys a lot of them use make the potential for oil pump disaster much worse. Inline fours have some harmonics that no matter how well the engines are balanced, you can't tune out. I have read the crank can flex a degree or two every time a cylinder fires. The stock crank damper or harmonic balancer absorbs some of this...it has a certain amount of mass and a rubber isolator between inner and outer sections. On Zetecs (and Miata engines) the oil pump surrounds and drives directly off the crankshaft nose, so it is where a lot of these hammer blow type forces wind up....although it goes throughout the engine.

 

Bottom line is if I was building an 8000 Zetec rpm engine from scratch, I'd probably use the billet gears if it was going to spend much time at close to those speeds....but in any case I would not be tempted to install the aluminum pulley on a wet sump engine......dry sump you normally use an external oil pump so vibration is not so much an issue.

 

I would imagine the power on the Supersport engines drops off past 7500, especially with a stock muffler, so no reason to run past that anyway. Dyno will tell the real tale.

Link to comment
Share on other sites

  • 1 month later...

I have a Caterham Zetec, cams, TWM Pectel 216 HP setup. It runs very rich but has run very well.

 

Recently it started to mis at 4,200 and again at 4,700. At first I thought it might just be a cold engine. Today I took it out after a 20 minute idle to full temp.

 

It had the same miss in 1st, 2nd, 3rd and 4th. I didn't get to 4,200 in 5th on the public hwy.

 

Any thoughts before I spend money on dyno time.

 

PS I will have to pay someone else to do this as it is beyond my abilities.

 

Thanks for your thoughts.

Link to comment
Share on other sites

Michael, since it's been running well and the mis so reproducible, my guess would be a loose sensor or some of the ignition wiring... If the crank sensor is loose and hits a resonance at 4200 rpm, it may feed the ECU bogus data. If you have the software and cable, it may make sense having somebody look at what's happening as it misfires (i.e. passenger with a laptop)... If that's not it, maybe theres an intermittent connection loss somewhere in the ignition system, again aggravated by some resonance at 4200...

 

Of course, I'm no expert in any of these things, so take this with heaps of salt ;)

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...