85 Tecate overheating

[dcreel]

What would make a Tecate just pour antifreeze out of the overflow as soon as the bike starts? The idle seems to be a little high as well.

I'm used to my 84 which runs top notch all of the time. The radiator and hoses are clear. The old radiator did have a lot of white crud in it. Last time I started it, it started with no leaking, until the trike was run for a while and it started overheating.

The cylinder head was leaking but not since the new head gasket was installed.

It is a KX250 cylinder, ported, with an intake spacer and a 41mm Mikuni falt slide carb. DG pipe and silencer.

How can you check the water pump without removing the cover? Can you look inside the radiator for signs in the fluids action?

Thanks in advance,
Doug

[tecat-z]

You mentioned you just replaced the head gasket........ You installed it flipped over. On the water pipe side of the cylinder, the gasket has a small restrictor hole. On the opposite side it is a long oval. The restricted side has to be on the side of water pipe. If not, the flow will overcome the spring in cap and push water out overflow just as to much heat will do when coolant expands. Think of it as a regulator. I guarantee this is your problem. :beer

[dcreel]

Thank you, I'll check that.

[cr480r]

I would check to see that the radiator has good flow and try a different cap... caps can go bad


You mentioned you just replaced the head gasket........ You installed it flipped over. On the water pipe side of the cylinder, the gasket has a small restrictor hole. On the opposite side it is a long oval. The restricted side has to be on the side of water pipe. If not, the flow will overcome the spring in cap and push water out overflow just as to much heat will do when coolant expands. Think of it as a regulator. I guarantee this is your problem. :beer

I cant see the head gasket causing this problem.. The restriction is there to alter coolant flow to cool the cylinder evenly.. when guys used o-rings instead of gaskets it doesnt blow the cap..

[dcreel]

Well, I followed the manual when I did it, so I'm pretty sure the gasket isn't in wrong. It was overheating before I changed the head gasket. Today when I started it, it came out of the overflow as soon as it started. It was also idling a little high.
The radiator, hoses, and cap are off of my working excellent condition 84. I think I am going to have to pull the motor and go through it. I was hoping there might be a fix someone else had gone through already. It runs great when it is running, the front wheel comes up in every gear with the throttle. It's a monster.. I just can't seem to get the overheating figured out. The head gasket isn't leaking anymore. I figured that was the reason for the overheating to begin with.
Apparently that wasn't the only problem.
It has a motoplat ignition, and I know absolutely nothing about that.

Can you put the disk, caliper, front wheel, and hub from an 85 onto the forks of an 84?

[fabiodriven]

Can you put the disk, caliper, front wheel, and hub from an 85 onto the forks of an 84?


I doubt it. I would think you would have to at least change the forks, probly the triples too...

[cr480r]

I doubt it. I would think you would have to at least change the forks, probly the triples too...

the tripples are the same

[cr480r]

. Today when I started it, it came out of the overflow as soon as it started.

sounds like a leaking head gasket or cracked cylinder...something besides heat is pressurizing the coolant

[tecat-z]

I would check to see that the radiator has good flow and try a different cap... caps can go bad



I cant see the head gasket causing this problem.. The restriction is there to alter coolant flow to cool the cylinder evenly.. when guys used o-rings instead of gaskets it doesnt blow the cap..

I know you wouldn't think so, but it makes all the difference in the world. I've done it and seen it happen. Oem gaskets have the 'UP' so this cant happen. But aftermarket gaskets can go flipped and not get noticed. The o-ring heads have no restriction at all and actually slow down flow of coolant. Completely different.:beer

[dcreel]

It was a new oem gasket. I noticed the up as well.