Re: cooling problems 93 DT85
I don't know what year they changed it but the head gaskets on the DT85 were redesigned at one point to reduce the clogging of the head with salt and corrosion. The new head gaskets allow better drainage of the cooling channels. You have tackled the worst. You may want to replace the water tube (or at least check carefully) for leaks at the top and bottom grommets. Also, if you have ever seen any evidence of the impeller blades having been thrown off, try backflushing the engine with a garden hose stuffed into the thermostat housing with a bucket under the water tube (remove the lower unit) to look for pieces of the impeller. Sometimes they can lodge at the base of the powerhead where the cooling channel takes a 90 degree turn. While you have the lower unit off clamp a garden hose onto the water tube and check for adequate flow and leaks up under the engine holder. Water is supposed to exit out the exhaust relief holes at the back of the driveshaft housing, the prop exhaust, and at the pee stream, not anywhere else.
