Toyota Valve Adjustment Info!!!

[Lon Ross]

Hi, this is for all who have solid lift cam Toyota's and have valve adjustments recommended for your truck. 1st. let me say I have 45+ years in the automotive industry and have been a mechanic, restoration specialist, professional racing motor builder and shop owner over those years.

I have read many post about Toyota valves and adjusting them. Here is the truth and the fiction on them. If your Toyota has adjustable valves, they NEED to be checked / adjusted from time to time. The same is true if you have a timing chain instead of a belt, it NEEDS checked! The chain most likely won't need replaced unless it has been abused by poor oil changing intervals or high RPM use, but checking it is easy when adjusting your valves. You don't need to remove it and measure it as recommended IMO, just make sure there is NO play in the chain and the plastic runners are all in tact.

Now on to the valves. If you have a Toyota that lets you adjust the valves by turning a adjusting screw, good for you. Many have shims that need measured and replaced with the correct tolerance shim for the current motor ware.

I have read that the exhaust valves will burn due to the incorrect adjustment because they don't contact the head long enough to cool if out of adjustment, WRONG. As a man who ported and polished many racing heads and built many high performance motors, this is wrong. The reason your exhaust valves not only have much more liberal specs then the intake valves, is due to the abuse they under go ALL the time. They run MUCH hotter due to the hot exhaust passing over them constantly. This causes a lot more ware at the seats as well as more stretching of the valve stem from the heat.

So if you check your valve lash, don't be surprised if your intake valves are still in speck and your exhaust is getting close to a burnt valve!!! That is expensive and easy to avoid if you check / adjust your valves every 40k or so. Good luck with you trucks, I hope this helps

 

[tibadoe]

Good info - thanks!

 

[gene]

Very true, I used to do my air-cooled VW's every three thousand miles. A tip: The valve adjustment screws might be worn now where they contact the valve stem. If so, you will see a very obvious wear pattern on the ends. If so, this might cause problems with maintaining proper valve clearances between scheduled valve adjustments. It did for my VW Karmann Ghia. I installed 8 new adjuster screws, and that made a huge positive difference! I hardly saw any variations doing valve adjustments after that. Since the 22RE is so similar, I bet they might have the same problem.

Hi, this is for all who have solid lift cam Toyota's and have valve adjustments recommended for your truck. 1st. let me say I have 45+ years in the automotive industry and have been a mechanic, restoration specialist, professional racing motor builder and shop owner over those years.

I have read many post about Toyota valves and adjusting them. Here is the truth and the fiction on them. If your Toyota has adjustable valves, they NEED to be checked / adjusted from time to time. The same is true if you have a timing chain instead of a belt, it NEEDS checked! The chain most likely won't need replaced unless it has been abused by poor oil changing intervals or high RPM use, but checking it is easy when adjusting your valves. You don't need to remove it and measure it as recommended IMO, just make sure there is NO play in the chain and the plastic runners are all in tact.

Now on to the valves. If you have a Toyota that lets you adjust the valves by turning a adjusting screw, good for you. Many have shims that need measured and replaced with the correct tolerance shim for the current motor ware.

I have read that the exhaust valves will burn due to the incorrect adjustment because they don't contact the head long enough to cool if out of adjustment, WRONG. As a man who ported and polished many racing heads and built many high performance motors, this is wrong. The reason your exhaust valves not only have much more liberal specs then the intake valves, is due to the abuse they under go ALL the time. They run MUCH hotter due to the hot exhaust passing over them constantly. This causes a lot more ware at the seats as well as more stretching of the valve stem from the heat.

So if you check your valve lash, don't be surprised if your intake valves are still in speck and your exhaust is getting close to a burnt valve!!! That is expensive and easy to avoid if you check / adjust your valves every 40k or so. Good luck with you trucks, I hope this helps

 

[Lon Ross]

Very true, I used to do air-cooled VW's every three thousand. (Perhaps a tip.) The valve adjustment screws might be worn out now. if so, this might cause problems with maintaining clearances. It did for my Karmann Ghia, I installed new ones, and wow, did that make a difference! I hardly saw any variations after that.

Very true, the valves work as hard as the pistons and are neglected more often then the rest of the motor that for the most part only needs regular oil changes and decent gas IMO.

The valve train is much more complicated, especially the chain and shims. the OEM chain runs on aluminum runners with special hardened plastic guilds, that if maintained properly, can preform for two hundred thousand miles +. Add some grit and grime from dirty oil and it will damage the valve train / chain a lot faster then it will the pistons and cylinders IMO.

So here is the deal IMO, check the valve clearance and timing chain ware, its easy, remove the valve cover and stuff on top of it, use a feeler gauge and if all is well, check the chain and guide's for ware. This is a good time to replace your valve cover gaskets that might be starting to leak, or will soon. so even if all is well, you have piece of mind and new valve cover gaskets to serve you for the next 50K miles or so.

On that note, the gaskets are supposed to not need any gasket sealer, well I have found they tend to leak between the valve cover and the gasket, instead of between the valve cove and the head. I put a small bead of red silicone in the valve cove grove before installing the new gasket, then a small bead on the gasket side that mates to the head.

You do not want to torque these bolts down, just hand tighten them starting from the middle and moving out in a cross hatch pattern. Giving them a couple of hours to seat, then repeat form center to the ends with a gentle tightening, you will feel when you start to get resistance, don't squash the rubber washers that come with the bolts, and yes, always use new ones. Hope this help someone.