Why all the blown heads???

OGMB2K

As I may have mentioned in other posts I am returning to the mini truck scene after being one of its founders back in the 80's. As I learn more and more about the B series trucks I can't help but notice the common theme of blown heads / head gaskets.
Was this an inherent defect in these trucks? Is it an inevitable repair? Or have all you whipper snappers been beating these 2.0L 87hp beasts like they were Hemi's?

MazdaMitch

What I think it is is the owners of the trucks do not periodically check the head bolts torque.

It's something that should be checked every few years at least.

Knock on wood but I've never had this issue.

Cusser

I got my '88 B2200 in 1994, now at 235K miles, and I've never blown a head gasket or cylinder head.

My guess is folks overheated their engines due to a coolant leak, bad radiator, bad thermostat, etc.

Drivers everywhere need to learn to pull over immediately if their engine overheats or loses oil pressure, don't assume you can go a few more miles.....

MazdaMitch

Cusser this is why I like to run the 180 thermostat so that I "have more time" to react if something goes wrong and it did once.

That small hose by the thermostat housing, the metal piece the hose was attached to, it broke.

Lucky for me I'm always eyeballing my gauges and I look down and saw that it was just a little more than halfway so I pulled over immediately.

For those that run a 195 it generally runs halfway to begin with at normal operating temperature so it could get away from you pretty quickly if something were to go wrong.

Axel-Breaker-Earl

Also, like Mitch has mentioned, the small coolant bypass hoses (the B2600i's have several on them that you can't really see!) only last about 15-20 years IF they are the MAZDA bypass hoses. Most of the aftermarket (even name brand hoses) don't even come close to that. I always try to source the Mazda hoses, but when they do develop a leak, the temp can rise very quickly......and the B2600i engine doesn't like this at all! Once an aluminum headed iron block engine gets too hot, the head gasket is usually compromised.

I learned a long time ago, to hoard those Mazda coolant bypass hoses!

Cusser

B2200 engine:
8mm i.d. bypass hose to – underside of Intake Manifold to Pipe on passenger side: Mazda FE87-13-116, S-shaped Gates 18100 (cut to length, special order O’Reillys), Gates 28408

10mm i.d. bypass hose parallel to cylinder head almost-straight hose going toward the /firewall
Mazda FE1H-15-288, Gates 28409

10mm U-shaped Bypass hose Mazda FE65-15-284B, Gates 18206, Dayco 71348

Heater hoses Dayco 87713 and 87712 special order AutoZone ; Gates 18900 and 18899
special order O’Reillys

Metal coolant bypass pipe: Mazda F214-15-290A