Hello Scotty,
I recently bought a used 1998 Toyota RAV4 4-door automatic from a private party for $6000 cash. It was in excellent condition with 52K miles on the odometer except for needing a right front drive axle boot replaced.
I put about 3000 miles on it and noticed it lacked a little power driving up hills. So I decided to have it inspected by a repair shop I trust that works on a lot of Toyota vehicles.
According to my 1998 Toyota RAV4 Haynes Manual, valve clearance check and adjustment is recommended every 60,000 miles or 48 months. Well, my vehicle has about 55K and is 25 years old. So, I decided to have that maintenance performed at a shop that I trust. I requested them, “Adjust the valves and do a tuneup if necessary.”
Later, I got a call from the mechanic. He reported that due to failed oil seals that are designed to keep oil away from the spark plugs, oil had fouled the spark plugs and damaged the spark plug wires. So he did a tuneup and replaced the wires. Parts and labor was $700! Ouch! So, out of curiosity, I called the Toyota dealership and the service advisor quoted me $820 for a tuneup and valve adjustment! $608 for the valve adjustment alone! $220 for the tuneup.
According to the Haynes Repair Manual: “2000 and earlier models use replaceable shims that ride on top of the lifters.” A special tool is required to remove and replace the shims.
My vehicle runs great now. I have no complaints, but I was curious if any of the valve clearances were out of specification. So I emailed the mechanic who owns the repair shop. His reply totally confused me. He said, “Dan-because they were pucks they never change.”
Now I’m totally confused! Didn’t he perform the valve adjustment in the same manner that is described in the Haynes Manual where you measure the valve clearance and if it’s out of specification then you adjust by inserting a thicker or thinner shim on top of the lifter?
Scotty, can you clear up my confusion?
Hi! Congrats on that new good condition car.
Not uncle Scotty. But you have to clear it with him in a good manner since I think you are good friends too or you just know him. Because yeah, that response is a vig twist in this message of yours.
Thanks for your reply Doc! I guess I need to stop reading about how to fix my own car and start doing it myself! 🤣
Engines that use shims under buckets operated directly by the cams rarely get out of adjustment. If they do it's a big job to adjust since you have to remove the camshaft in order to change shims.
Those with rocker arms and mechanical adjusters (such as Honda) are more likely to actually require adjustment but it's much easier to do.
I had my brother-in-law who is a mechanic with over 40 years experience listen to the engine and he said it sounds normal.
That was the wrong answer from your mechanic. If the valve clearances are out of spec, a new shim (puck) is installed to bring it within spec. If he checked all the clearances and they were OK, there was no need to put in the new, correct size shim.
Fixing your own car is a very satisfying experience.
If oil is fouling the plugs, it could well be the valve cover gasket. That likely was to be done when adjusting the valve timing, and the plugs and wires should have been nearly no labor cost.
Was the timing belt replaced?
The timing belt was not replaced.
How, exactly, is a leaking valve cover gasket going to foul a spark plug? @nlord
At the bottom of each of the 4 spark plug tubes there are threads that are sealed with FIPG. I think they removed the spark plug tubes with a pipe wrench and resealed them with FIPG.
At the bottom of each of the 4 spark plug tubes there are threads that are sealed with FIPG. I think they removed the spark plug tubes with a pipe wrench and resealed them with FIPG.