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34 minutes ago, knight1fox3 said:

Just shy of 150k on the Infiniti and still have the original timing belt. :thumbs:

I thought they used a chain?

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I don't know for sure.  But either way, it hasn't been replaced.

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1 minute ago, knight1fox3 said:

I don't know for sure.  But either way, it hasn't been replaced.

Looks like it's a chain.  Those should be good for the life of the engine.

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I thought if your timing belt or chain broke your engine would just stop running I didn't think it would actually break?

Mine Broke in a 1984 ford ranger once and I just sort of came to a stop and had to get the chain replaced

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3 minutes ago, MetsFan said:

Looks like it's a chain.  Those should be good for the life of the engine.

Another +10 for Infiniti.  Which coincides with the make of the car. :D

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4 minutes ago, Road Guy said:

I thought if your timing belt or chain broke your engine would just stop running I didn't think it would actually break?

Mine Broke in a 1984 ford ranger once and I just sort of came to a stop and had to get the chain replaced

Depends if its an interference fit motor or not.  If it is, you're going to bend a bunch of valves.

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^Yeah, and my Aveo has an interference motor.  $658 to replace the belt, along with the water pump.  Apparently the water pump is run off the timing belt?

Not too bad considering it's the only major service I've had to do in 10 years, and hopepfully will last another 10.

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I believe that in general smaller engines have a belt as opposed to a chain.  I don't know for sure, but I suspect that it's the older designs that are interference as it's a pretty poor design choice to have the integrity of the engine depend on a rubber belt.

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1 hour ago, mudpuppy said:

^Yeah, and my Aveo has an interference motor.  $658 to replace the belt, along with the water pump.  Apparently the water pump is run off the timing belt?

Not too bad considering it's the only major service I've had to do in 10 years, and hopepfully will last another 10.

Not likely.  I know with my old Mazda the water puump impeller was plastic and had a finite life.  It sits in very close proximity to the timing belt so it's best to replace them both at the same time when everything is disassembled than to do them independently and have to tear everything apart twice.

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1 hour ago, MA_PE said:

Not likely.  I know with my old Mazda the water puump impeller was plastic and had a finite life.  It sits in very close proximity to the timing belt so it's best to replace them both at the same time when everything is disassembled than to do them independently and have to tear everything apart twice.

 

Here's a picture.  I believe the gear on the lower left is the water pump.

timingbelt15.jpg

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^^^ Yep.  My Porsche setup isn't that far off, but uses the backside of the timing belt to drive the pump instead.

MA - There are a surprising number of small, interference fit motors out there.  It has largely to due with getting as much power/efficiency out of a small engine as possible.  Higher compression and variable valve timing often have a lot to do with it, and clearances in that chamber get awfully tight.  More often than not, if they want the motor to have a small footprint, they will use a belt, since it makes packaging the water pump and accessory drives easier.  They can also help valve train life by damping some of the engine harmonics.  

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Thanks.  I guess that makes sense but I still maintain that trusting the life of the motor to a belt is not a sound engineering decision.  Kinda like suspending tunnel ceiling panels over a very busy roadway using only a epoxy adhesive anchors.  Can you say Big Dig?

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I'm not a fan of the belts , but it's not as though timing chains have never jumped a tooth, either.  

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This is why we went into engineering to make fatty money so when timing belt/chain goes bad or instead of getting an oil change we just go buy a new car.

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Saw this on my walk today. LOL

2fe9b56633fa49bd4e51881b3d8c7efc.jpg

Sent from my SM-G925V using Tapatalk

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Got the Porsche running yesterday.  Confirmed previous suspicion - royally f'd up cam/cam housing was the culprit.  Fired right up no issue this time (once the coil wire was connected, that is *ahem*).  Whether it moves under its own power remains to be seen.  Need to throw some gas in it and let it idle a while one night this week.  I forgot to connect the fan thermostat wires, so I need to make sure they'll kick on.  

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I also went to the NASCAR all-star race on Saturday.  Unfortunately qualifying got rained out, which is a shame, because the three laps + no speed limit pit stops is probably the best part to watch.  Had killer seats though, 15 rows up, just left of the start/finish line.  Got a good view of Tony Stewart's wreck - he slid to a stop just about right in front of us.  Stunk that my two most hated drivers finished 1-2, though.  Was really hoping Kyle Larson would pull it off.

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Had the Porsche buttoned up.  Was letting it idle to see when the fans would kick in, then gurgle gurgle out the water neck.  Ruh roh.  Temperature got hot after the fans didn't kick on.  Turns out male spade was wedged between connector and jacket, not into the connector itself.  Fixed that, and fans came on no problem.  Whoops.  Guess I'll redo the water neck tomorrow night or Saturday morning, then cross my fingers and head to CMP on Monday for the next race.  Probably get my ass whooped, but fun just the same.

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Well, the new old motor smokes like a banshee but runs just fine.  It's down on power compared to the old motor (worn rings), but was reliable and still pulled pretty good up to about 5000 RPM.  Put in a screamer lap after the rain hit after gapping myself from the lap traffic, and eeked out a .005s margin of victory for my class!

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Double bonus!  Found out my time from Monday is also the class record! :woot:

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nice!  by 5 milliseconds.  Now you have a new target to beat.

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And the car isn't even dialed in yet.  Needs a more aggressive alignment (I'm rolling the tire shoulder, needs more negative camber and some toe out), and it's still 200 lbs over the class minimum weight!

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