Angry Coolant

[Paysts]

1985 Honda 250R

The problem is, and I thought it was with the cap (so I replaced it with a new one) my 250R leaks coolant.

1. Is coolant supposed to bubble and leak out exhaust gas (because it CLEARLY smells like exhaust gas) when the cap is off? I know the radiator fluid sloshes because of the pumping of the water, but this thing literally blows smoke out the water!

2. If it is leaking exhaust gas from the headgasket (which I just had replaced) would this cause pressure to build up in the cooling system? Because my 250R leaks everywhere! Coolant drips from the exhaust pipe, from the muffler, from the end of rear shock assembly, leaks all over the header pipe, and looks like it is leaking from the right side radiator assembly?

[brapp]

i have a brand new set or 85 rads with new hoses factory take off 75 bux for everything.

[random-strike]

sounds like a headgasket to me.

[Bryan Raffa]

yep its a head gaskit!!

[Dammit!]

When you replace a head gaskest on an R;

1. Use a Honda gasket

2. Use "Copper Spray" on both sides of gasket

3. Torque properly, heat cycle, then torque a second time

If you did all those and it's still leaking, check for warpage. Actually you should do that when you do a headgasket anyway.

[crackshot]

Is it really necassary to re-torque head after using copper-kote?
That stuff bonds with heat.

[Dammit!]

Yes. The bond isn't going to help if the head isn't on tight. The expansion and contraction of the head/cylinder/nuts will leave those head bolts fairly loose if you don't do it.

[random-strike]

i never heat cycled the bolts on my mustang and it takes a boosted beating dailey *knock on wood*. :)

but im sure its a good idea.

[crackshot]

Yes. The bond isn't going to help if the head isn't on tight. The expansion and contraction of the head/cylinder/nuts will leave those head bolts fairly loose if you don't do it.

So you trying to tell me Honda does this with every wheeler made?
They run it off assembly line, heat up cool down and re-torque?
We never did that when I worked for the japs.

[random-strike]

So you trying to tell me Honda does this with every wheeler made?
They run it off assembly line, heat up cool down and re-torque?
We never did that when I worked for the japs.

i dont know if they do or not, but those engines had not been ran and taken apart before, they are brand spanken new, with spanken flat surfaces.

[crackshot]

i dont know if they do or not, but those engines had not been ran and taken apart before, they are brand spanken new, with spanken flat surfaces.

Right. and prep is 90% of the job on rebuilds.
Everytime I have did good prep and re-torqued to find that bolts are as tight as they were installed on first torque during assembly.

[Paysts]

When you replace a head gaskest on an R;

1. Use a Honda gasket

2. Use "Copper Spray" on both sides of gasket

3. Torque properly, heat cycle, then torque a second time



Let me see:

1. No.

2. NO, and to be perfectly honest, I'm not sure what you are talking about, I have never heard of copper coating you apply to a deck and cylinder head (and I hope you don't think of me as ignorant, I just haven't work on a 250R).

3. No. My Clymers book did not mention anything about it.

[MTS]

Head gasket is fryed.....Have both the surface's deckd, Use a Honda Gasket, Use Permtax-high tack spray or kopper coat spray, I alwasy like to use new headnuts too.....The old ones expand and get weak overtime...causing them to come loose a little easier, ALWAYS re-torque after the first Cooling cycle......It only takes 5 mins and can save you a big headach, Another tid-bit, With the Old head gasket (or none at all) torque the head nuts down a few times Before re-assmebly, the nut will hold the proper torque Longer and better..

[Dammit!]

Let me see:

1. No.

2. NO, and to be perfectly honest, I'm not sure what you are talking about, I have never heard of copper coating you apply to a deck and cylinder head (and I hope you don't think of me as ignorant, I just haven't work on a 250R).

3. No. My Clymers book did not mention anything about it.

1. Never use anything but a real honda gasket for a headgasket. There's three options. ATC250R, TRX250R and '89 CR250R. All three of these will work but all three are different. The ATC is a three layer gasket, the TRX is four and the CR is a single layer. Less layers = more compression. If your motor is basically stock, use the ATC gasket.

2. You can get copper spray at just about any auto parts store. You only apply it to the gasket itself, not the head or cylinder.

3. Also forgot to mention when tightening those head bolts to begin with, use a criss-cross pattern to make sure it's on there nice and flat. Re-torquing them after a heat cycle is just good practice. Some people may get away with not doing it but, it only takes a few minutes. I'd bet you money that after you give it one good ride and let it cool all the way down, they're not going to be at factory spec anymore. I've done it twice in the past year and both times they had loosened up a bit. Not enough to cause a leak right away but definitely enough to be a concern and possibly cause a problem later.

[Billy Golightly]

You can use aftermarket gaskets but its kind of hit or miss. I've gotten some good ones before, and I've also got some that didn't last 2 days without leaking again.

I also agree on getting the head AND cylinder surfaced. It might be a pain or cost more to have the cyl studs pulled but just do it because then you know its flat.

[random-strike]

Head gasket is fryed.....Have both the surface's deckd, Use a Honda Gasket, Use Permtax-high tack spray or kopper coat spray, I alwasy like to use new headnuts too.....The old ones expand and get weak overtime...causing them to come loose a little easier, ALWAYS re-torque after the first Cooling cycle......It only takes 5 mins and can save you a big headach, Another tid-bit, With the Old head gasket (or none at all) torque the head nuts down a few times Before re-assmebly, the nut will hold the proper torque Longer and better..

good advice

[BigGreenMachine]

Yup your head bolts have come lose I'm sure of it. Had it happen after about 3 heat cycles on my Tecate (too eager to ride and forgot to do it). Heat cycles meaning getting the bike up to running temp then cooling completely.

Cometic makes a great head gasket and its all I dare use for the topend of my trike.

[jason 32]

hi do you have water in oil?cases could be cracked?oil seal could be blown