1991 4 Runner with Burnt Valve - Options?

I would go with 'valve job at local trusty mechanic' - but have him check the rings and Plastigage the crank to decide if more work is needed at this time.

Rick's recommendations the last time this question came up was to do the rings while it's open, just ream the top cylinder ridge, pop out the pistons and mike the bores. If all the cylinders are clean and even without too much wear, put new rings on the old pistons, run a ball hone down the cylinders to get some crosshatch, put the pistons back in and button it up. If you find something hairy inside, you can get the block bored out to clean up and a fresh set of oversize pistons.

Having your own engine block reworked is always preferable to getting a mystery block elsewhere - you have a known quantity, less chance for surprises.

And do all the seals and the water pump while it's apart, and timing chain & chain guides if it's getting noisy. Do it right, and hopefully ;^) you wont have any more major problems for another

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I just did my top end this week. I had a bad cam and two bad rockers. I removed the head and found some head bolts were carboned up so my head gasket was leaking. This was the cause of my conpression in #4 cylinder being low.

I had to get the cam bearings line bored. I checked the head and found it was planed before. Luckily it was still flat. I checked the mains while the pan was off and they were ok. I changed the cam, two rockers, fuel filter, timing chain set, valve seals, oil pump and gasket set. Total cost was about $700 Canadian with $90 of that being the line bore job. I lapped the valves. It helps if you could do the work yourself.

Chances are the $1500 valve job may find something else.

Good luck.

Yes - The mechanic's labor. An expert will spend two or three days on this work (and an amateur a lot longer), not counting the machine-shop labor on the heads. If you can do all the work yourself (and have most of the tools already) your prices would hold - add in paying someone else for the labor or buying expensive tools, and the final cost jumps.

A leakdown test should be performed before starting the work so they can see if any other cylinders have big problems. Again, more mechanic labor to deal with.

But if you don't have a ton of money to just do a custom engine rebuild from scratch, it's best to do everything needed while it's open - so you aren't duplicating the labor in a year, when the timing chain gets really noisy or the water pump starts leaking...

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Thanks for the extra info. I've never worked on a flathead Model A, but my limited experience is from pushrod motors. You sound like a Toyota Tech since you're quoting warranty claim info? If so was your last sentence what your shop would estimate the job to take?

Bard

Bard, yes, for a 3.0 V6, a valve grind (we do our own in house valve grinding) would come to just under $1300, more if you add items like timing belt etc.

Thanks again. I'm sure this info will help out Finnbow. Makes you wonder why his dealer wanted $3k though.

Bard