Cylinder head

[Buck Rogers]

I bought my '94 Toyota pick-up new in Feb of 1994. It has never, ever overheated, not even for a minute.

At about 75k, I had to replace the cylinder head because the casting developed a leak which allowed coolant to come in above one of the exhaust valves. It did not appear to be a heat crack, but rather a weak spot in the casting.

Now, at 184k(109k later), it developed a hole between #1 and #2, on the side of the head, in the valley between the exhaust ports, where the manifold bolts up. The coolant leaked to the outside of the engine. I believe that it is also a weak spot in the casting. I was able to fix it with a screw and Loctite's version of JB Weld.

Can anybody give me any insight into this? I am about ready to abandon the vehicle which I had planned to drive for at least a few more years, and get a Chevy. My dealer also informs me that I need a timing chain, so I feel like I may be throwing good money after bad.

Thanks.

[natenelsen]

okay, the timing chain is a problem on these vehicles, however there is an after market chainguide that fixes this problem. As to the cylinder head, being a ferrous block and an aluminum head makes these motors unforgiving of improper coolant mix. Be sure to follow the manufactures recommedation on the coolant mix. The heads I have seen with the leak above the exahaust have all been from galvanic "rot". They are good little trucks and with minimal care they regularly last 300k miles between motors.

Nate

[Buck Rogers]

[quote=natenelsen]...a ferrous block and an aluminum head makes these motors unforgiving of improper coolant mix. Be sure to follow the manufactures recommedation on the coolant mix....

Nate,

Would that be something besides 50% distilled water and 50% ethylene glycol(or whatever is in the standard green anti-freeze)?

I've always replaced it on an annual basis. It has never come out rusty or anything but clean.

Buck

[natenelsen]

Sounds like you got it right, I have never seen the problem that you described and fixed with locktite. I have had the leak onto the exhaust valve, I just welded that up and it has come out just fine. It too bad you have had this trouble with your truck, they are usually really good little trucks.

Nate