An earlier thread prompted me to pull off the exhaust manifold to see if antifreeze had been leaking into it...when I removed the manifold, a little bit of coolant did leak out. Left in there was a congealed substance w/ a green tint! i had no idea antifreeze would do that. I checked both the manifold and chambers and both are still smooth and havent rusted...so my question is, since the coolant is leaking, what seal tdo I need to replace and where is it?

Mary

 

there is also some standing coolant in there, but it is clean...I think the fluid came into the camber when we moved it onto a trailer for the 3 hour drive home...

 

I work at a VW dealership, and we use a pink coolant, and if it is mixed with either green or roange coolant it will congeal, and not circulate.


maybe some sort of contaminate got in your system to make it congeal.

since you did fine it congealed i would flush your whole cooling system!!

 

The 12a I just pulled apart had that crap all inside of the coolant passages. Bad juju. Flush your system before it is too late!!!

 

If oil and antifreez mix it will do the same thing, which with rotaries is very likley the case.

I once had to tear down an engine (GM 3.1 V6) that the owner ran the car for "a while" with the intake gaskets leaking coolant into the valley--> thus into the oil. I had the engine upside down to pull the oil pan off, when the pan came off the oil/antifreez mixture was "jello-molded" to the shape of the pan-- and the engine actually did run like this.

 

yeah the **** is nasty!!


When the water to oil cooler in some of the VW's we get Chocolate milk....Not as bad as contaminated cross coolant, but still nasty!! I think the pink coolant we use doesnt become affected by oil the same way green and orange coolant does.

 

from what ive learned if there's coolant in the exhaust system, that means its in your engine, which means you blew a coolant sear, which means you need a rebuild.

 

Does this require a complete rebuild? Is the engine worth trying to get running? Can I replace the seals w/o a complete teardown?

 

if your coolant seals are blown (im not saying they are) you would need to completely rebuild the engine. the coolant seals are on the inside of the engine.

 

First things first, you should remove your upper and lower intake manifolds and change out the O-rings there that route coolant from the block into your lower intake manifold. These are very common pieces to degrade over time, and will cause symptoms that look like an engine water seal failure, i.e., coolant burning in the exhaust and radiator going down without any obvious leaks.

Replace those O-rings and then go from there. If you also have coolant pooling between the lower intake manifold and the engine block, chances are these O-rings are bad.

As far as the coolant congealed in the exhaust, this is fairly likely to occur, since the hot exhaust gas will cause any water to evaporate off leaving only the glycol and ethylene as the precipitant - in other words, it'll dehydrate the coolant until only the green goo is left.

Take it from there and see what happens. If the engine still starts and runs well, I wouldn't be too concerned about coolant seals going bad just yet. Those would require a complete engine teardown and rebuild to replace, but my car has over 188k miles on the original engine (13b) and is still going strong with no coolant leaks...

Reply back with what you find, Mary,

 

Hey thanks a bunch, I will pull it off today, But just out of curiosity, how hard is it to do a rebuild? I think I read that it is pretty simple if you have the few specialized tools....

 

OOOOOOOOOk. I pulled it off.....The outer 2, and the inner top 2 are part of the air intake, the 2 w/ O-rings are cooling passages....what is the center bottom one? it has black buildup on there...I guessed something to do w/ oil? When the lower intake came off, some anti freeze came out(and when turned, a little more dribbled out of the manifold. There is congealed anti freeze in the 2 passages w/ O-rings(almost all of it is in the right one though). Only what appears to be maybe a slight amount of surface rust on the intake ports. I think the simplicity of these engines is part of what is so facinating about them.
So, is this going to be drivable if I put it back together w/ new O-rings? Is it worth continuing to work on? Is it going to require a rebuild? If so, is it possible for me to do a rebuild myself? We are rather short on money right now w/ the baby and all....

Thanks,
mary

 

Ttt

 

Well, you described that the intake passages are clear, which is what you'd expect - even IF you had an antifreeze leak from the coolant passages. Reason being, you have a lot of airflow along here and it will keep the antifreeze moving into the intake cycle if there's any 'blowby' from the O-rings.

At this point, you're no worse off than before, and actually better; you'll replace the O-rings and then know that this may not be the cause of your congealed coolant issue. When you removed the lower intake manifold, it's completely normal that some coolant would be in those passages and run out when the manifold came off.

I'd put the new O-rings in there while you have it off, get a new gasket mounted, and put it back together.

If you're still concerned about a loss of coolant at the radiator, you might start looking for pinhole leaks that only occur under high rpm and pressure (high pressure for a radiator is 10-12psi, not much at all). These leaks can be caused by rocks dinging the front of the radiator and you may not even see it because it dries up so fast being as hot as it is.

Editing; The 'center-bottom-one' that you described is used with the airpump to inject air into the exhaust passages of your engine. For this reason, it's very common for that port to be black, gunky, and sometimes oily with burned up carbon and crap in there. That's normal. The EGR valve on the lower intake manifold takes airpump (AP) pressure and routes it to the exhaust ports to help cool them during deceleration - also helps to get cool, fresh air into the exhaust to help burn up any hydrocarbons and have cleaner emissions. That port won't need to be cleaned up or anything - just make sure it has a good gasket seal to prevent any unusual noises from the exhaust and AP when the EGR opens.

Reply back here or start up a new thread if you think you still need to pursue the problem. HTH,