DT 25 runs bad

[dougs94]

First off, let me say thanks for a great forum, I've been reading some old posts and already learned a lot.<br />Just bought a '92 DT25 and took it to the lake today. Didn't think I'd make it back to the ramp.<br />First thing I noticed was the cooling stream, it wasn't really a stream, more like a spatter. Should there be a steady stream? The motor seems to be running on 2 cylinders and I noticed a drop or two of water around the head heat sensor. Could this be a sign of a head gasket problem?<br />Thanks in advance, I'm sure I'll have more questions.<br />Doug

 

[jim dozier]

Re: DT 25 runs bad

You need to check to see if the engine is/was running hot. The top of the block (not the cylinder head) just behind the flywheel should be cool enough that you can leave your hand there a few seconds without burning you. If its running hot, I would fix the cooling system, (water pump, thermostat, etc) first. The pee stream should be strong and constant although a clogged pee hole won't hurt the engine just the stream, blow it out with compressed air to check.<br /><br />Check the spark plugs, 1. to see if you have spark on all cylinders and 2. to get an idea if there are other problems (lean cylinder, water, etc.). While they are out, do a compression check.<br /><br />The spark plug check may lead to fuel problems such as a need for a carb rebuild.

 

[dougs94]

Re: DT 25 runs bad

Looks like it got VERY hot, the heat sensor is melted as are the plug wires where they were touching the head. Looks like a melted gob of plastic in the water passage. Lots of water in the bottom cylinder.<br />All 3 plugs are firing.<br />This one needs work!