mrsnocrazy
New member
New to me 04 sx viper is leaking coolant... Seems to be seeping somewhere around lower part of front heat exchanger. No drips higher on the ex, but there are some scratches where the studs hit by previous owner. I have checked the water pump and left papertowel under there for a few days water pump is bone dry. I was thinking it could be a rub through under the engine?? It's very hard to see but I don't think its the cause there isn't any coolant sitting in the belly, aside from the few drips from removing carbs. I have read here somewhere about the ex rubbing where it meets the frame on steel? I am confused where that is? Weird part is only drips when the temp warms up outside. It was 15c here yesterday... Carbs air box and pipes are out. I'm hoping I don't have to pull the engine, never done that before. Sled is bone stock btw, with 7500 km
roudyroy1
Active member
hmmm, does it leak when running it?
mrsnocrazy
New member
It did not leak when running it. But... The only running it has done is on trailer and off trailer. I did notice the next day there was a few small drips on the floor (temp outside was warm), which began my hunt for the cause
staggs65
Moderator
I had a leak on mine from where the plates inside the tunnel for the rear suspension mounts rubbed through the running board exchangers. It would just weep and wick it's way down the edge of the exchanger to the front where it would eventually form a drip. I searched for the source of that leak for a long time until I pressurized the system with air and sprayed soapy water on everything.
I chased one on an SXr one year. Pressurize it for sure. that will be the easiest way to tell (IMO).
Hammer Down
Member
Is there a trick or something to pressurize the cooling system. I rented a pressure tester from Napa and none of the fittings would fit the small radiator cap.
staggs65
Moderator
have a friend hold a rubber tipped air nozzle in the rear bleeder hole. You don't want to put a lot of pressure to it. it only takes a few psi to find the leak.
mrsnocrazy
New member
I was able to rig up a tester to one of the hoses with a gauge and pressurized it to 10psi. Dropped 1 psi overnight. Odd thing is I can't see any more drips of coolant near the front heat exchanger... I was able to see with a small mirror a few drips under the motor close to the hose that's connected to the water pump ( water pump is not leaking).. However, I am not convinced this is the problem. Am I missing something? What is my next move?
how full was your coolant system? Could it have come from the overflow?
mrsnocrazy
New member
I filled it up to cold fill line before the pressure test. It was about 3/4" below the cold fill line before. For the pressure test I temporarly re routed the overflow tube and placed a paper towel under it to ensure it doesn't leak in the belly
mrsnocrazy
New member
I am testing through the mag side hose that connects through carbs... Would the thermostat prevent the test to enter the coolers, or is it flowing through the entire system?
Im pretty sure there is a small hole that ALWAYS lets a small amout of fluid to pass the thermostat so no it wouldn't.
staggs65
Moderator
X2, that should still put pressure on the entire system.
mrsnocrazy
New member
Well, pressure hasn't changed still just shy of 10psi. No more drips that I have seen..I am still not convinced, problems don't exactly just disappear. Is there a chance since the system is "cold" the leak would not appear? Even under a pressure test? I am waiting for some carb parts, as soon as I get the carbs back together I will for fire it up to warm up the system. Any one else experienced this problem?
I also should add the previous owner installed a 1 1/4 ripsaw that's studded. I am not sure of the stud size, but I'm still running the 9 tooth driver. I read you must go down to the 8 tooth for clearance at the exchanger. There is at least 3/4" between stud tip and exchanger. Is this safe to continue to run this setup? There are some marks from stud damage, but the track was waaaay too loose. I have tightened it up to a bit tighter that spec.
Thanks again for everyone's help! I love this forum!!
mrsnocrazy
New member
Seems like I do have a leak. Left hand running board exchanger. Still not quite sure where its leaking from, but it appears around the footwell area. I also noticed the coolant had a "brown" tint to it.. Not milky whatsoever. Is this just a certain type of coolant, or do I have a head gasket leak or some other problem?
Just seems like one issue after another...
Just seems like one issue after another...
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staggs65
Moderator
Check where I described in post #4
mrsnocrazy
New member
I am not sure if that is where the leak is coming from.. I pressurized the system sprayed soap and water everywhere including the area you decribed. No bubbles. Is there a better way to see if this is where the leak is from? It does sound like this is my problem.. I just want to be sure. Will I have to remove the entire exchanger to get it fixed up?
staggs65
Moderator
You'll have to remove the mounting plate. the cooler can be welded in place
staggs65
Moderator
If the coolant is drained and you pressurize with air, soapy water should show up any leaks right away.
mrsnocrazy
New member
That's what I thought too. That's why I am confused. I have no clue how the system can hold pressure when it's under test with air, but as soon as there is coolant in there it leaks. I put carbs and air box back on yesterday and ran the sled to operating temp. The head got really hot.. Hot enough I could barely put my hand on it. I later realized more drips by the footwell again. I guess I will have to drain it again and find a way to get the cooler welded