2001 toyota mr2 spyder engine

Last week while driving to work my car started smoking and then died. After doing some digging around we found out that it was the engine. After taking it out the cause of it was a loose bolt on the exhaust cam, and this caused the key way to break. Which caused the shift in valve timing to destroy cylinder #3 exhaust valves. We are looking at either fixing this engine or getting a rebuilt. The problem with fixing it is that it is an all aluminum block and head. There is no way to see the cast iron sleeve. It also has water circulation joints like the old Vegas had aka free standing and 1cm thick. We are looking at the type of engine and comparing them. We are considering Jasper, Surefire, and Martin. We also checked Marshall but they have none. We would like to know if we should buy a rebuilt engine and if so what brand, or should we fix this one. Also this engine only has 40k miles.

This must be the first case of a Toyota using engine construction methods similar to the Vega.

Yeah.

Did you remove the cylinder head, yet? If so, you should be able to see the cylinder lining when you rotate the #3 piston to BDC. At 40K, there should still be cross-hatching marks on the cylinder walls, if the rings are still good. Did the #3 exhaust valves damage the piston, or just nick it up? If just nicked, you could use a dremel tool to smooth out the nicks, to prevent hot points, and then look for a reman cylinder head.

If reman engine is the way you want to go, Jasper has a very good reputation.

Once the head is removed the cylinders should be able to be inspected. You’ll want to check the pistons for damage also. Remember that even though #3 may have the only damaged valves, the entire cam was thrown out of whumpus. Nothing was broken and inside the cylinder, so the chances of having cylinder wall damage are low.

Personally, I’d fix the one you have. I see no reason not to. Unless when you get the head off you discover that the valves banging onto the pistons did more damage than you expected. If that turns out to be true and you’re looking at a total rebuild, then I’d consider the Jasper engine. A home shop simply cannot do as good a job on a rebuild. The Jasper rebuild will have its block and head cleaned in vats and radiographed, its parts checked to factory specs, and all the proper machinery to do the honing etc. etc. correctly and accurately. Unless your garage has all the cleaning and machining equipment as well as a nice programmable coordinate measuring machine to check the measurements, you’re better off with theirs.

After pulling off the head further inspection revealed a hole the size of a quarter in the #3 piston. There are fairly deep grooves in the cylinder walls. Portion of the aluminum head melted to the piston. I would imagine then we will be calling Jasper up. Does Jasper have a distribution center in the Kansas City Metro? Will post pictures tomorrow.

Here are the pictures that I promised.

here are some more.

Ouch! . . . that’s gotta hurt. Good luck with the new motor . . . never heard of this with a Tojo before, I hope this was a fluke. Rocketman