"Vehicle needs valve clearance adjustment/Throttle and fuel system cleaning"

do u know what is the best numbers for the 3.4 5vz. i have the same noisey tick, measured all valves to find all of them iin spec with extremly noisy valve train with hott spots and chips on the cams //....exhaust valves were in spec at .013 give or take a thousandths on both banks, found a thread saying .015 is the best cause the exhast valvees heat up ???? what would u set your exhaust valves too. what the optimal number for intake and exhaust while running a s/c ..


5vz valve clearence specs intake .006-.009
exhaust .011 -.0014


measured clearence intake .007-.008
exhaust .012-.014

 

Seafoam is fine. Used it on a gmc and did work well. I use it on EVERYTHING that has a motor and no issues.

 

The last time I looked at the service manual, there is no actual shim, the buckets themselves come in different sizes. The maint. sched. calls for a clearance check at 80K. Unless the engine had been run at high rpms for most of it's 80K, i'd be surprised if it needed an adjustment. They will typically tighten up and loose clearance. My last experience with this system other than on a bike, was my sons focus ZX3. Required check at 75K. Checked it at 80K and found valves to be nominal. Again no shims, different size buckets. The oil you run will make no difference since this wear occurs in the upper cylinder.
Get them checked, the consequences are burnt valves.
I'm not sure I'd trust most dealers to check, because everybody would require an adjustment (that they wouldn't do) regardles of the actual clearances.
This may be a good subject for a poll. Who has >80 and have had the valve clearances checked? If yes to both counts, were the clearances OK or was adjustment required.

 

You probably ruined the Mazda engines beacuse they are Rotary engines with Apex seals which damage very easily! Carbon buildup is normal on all cars(a by product of combustion).Using sea foam or another foam type carbon cleaner WILL help clean and blast the carbon off the valves and combustion chambers and save you money.No need to adjust the valves!

 

Other that it being a PITA I'm not sure why you guys are so down on adjusting valves. Valves on motors frequently need one adjustment after break-in.

If you adjust them right into spec, they will usually stay there basically forever. If you let them start wearing into the valve seat and they get too far out, to the point where starts are hard etc, its basically too late and you need to re-machine the head etc, they will just keep drifting.

Kind of sucks, but its good preventative maintenance. You might be fine until 250k, you might not. Its worth a $10 feeler gauge tool and a couple hours of your time to at least check.

 

anethema,

got a write up for this?

 

Don't sorry just the service manual pages. Mine were in spec so I was fine, and they usually are, but sometimes you just have to adjust them. Too bad they don't use shims though since you can have a big shim kit on-hand, but just gotta grab the part from the stealership.

Here is the service manual section on checking and adjusting them, including specs. Good luck!

 

It says here in the fine print all the valve parts ware at the same rate so the valve adjustment should remain correct for the live of the valve. This type of shim adjustment has been used at least since the 40's. Toyota says listen to them I think at 80K if they are quiet leave them alone. If they get tight your compression and performance will suffer and eventually it will burn a valve the old 3 liter would tighten up and burn valves.

 

I don't see that fine print in the service manual but maybe I'm looking in the wrong place.

Their maintenance schedule has the valves being checked every 60k miles and adjusted if necessary. They also do not use shims, you actually change lifters to the proper size.

Again the check doesn't take TOO long, couple hours. If you catch a valve that is starting to move early, its a big boon, compared to trying to make a big adjustment later. Usually once you put them nicely in spec, they will stay for damn near ever, and if you keep checking every 60k, you're laughin.