cooling possible cracked head question - Snowmobile Forum: Your #1 Snowmobile Forum

gunnin88 · 01-23-2013, 02:43 PM

I just purchased a 2004 rev 800. I rode it about 1/2 mile and it blew the coolant cap clean off and overheated a little. I am getting ready to tear into it this weekend and try to find the problem. 1st I thought I would delete the tstat. My question is how can I diag a possible cracked head or blown head gasket without pulling the head? I do not want to buy a gasket and go through all that work if it is something as small as a bad tstat.

thanks for the help...Jason

g1teg · 01-23-2013, 05:21 PM

I dont know if your T-Stat could be the problem, but last week I blew an oring on my sled under the head and I had pressure in my coolant as well. I replaced the Oring and its proper now.

**BC_Dan** · 01-23-2013, 08:13 PM

Try taking the cap off and starting the engine. If there's exhaust in the coolant, there's a leak in the head or base gasket. It should be pretty easy to smell and see. A bad leak will also build pressure in the cooling system very quickly without the coolant getting hot.

**smallengineguy** · 01-24-2013, 03:49 AM

You gotta stop posting in 5 different threads about the same problem. Do what everyone has said in your other threads.

**kccats** · 01-24-2013, 07:30 AM

Does the exhaust smell sweet?

gunnin88 · 01-24-2013, 11:28 AM

Thank you guys. Smallengineguy worry about more important things dude. I use my phone to post here and finally found the tech area. Besides this info I got here is different, go see for yourself.

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gunnin88 · 01-24-2013, 11:30 AM

I have a cooling system pressure leak tester for cars. I thought maybe i could use that too to test if system is leaking through head.

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**smallengineguy** · 01-24-2013, 05:21 PM

Sorry dude, just giving you suggestions. Check to see if the exchanger is getting warm under the tunnel.

Josh Kidner · 01-24-2013, 06:05 PM

Quote:

Originally Posted by smallengineguy

Sorry dude, just giving you suggestions. Check to see if the exchanger is getting warm under the tunnel.

Sorry but he is right. You shouldnt post the same question in different threads. Anyway like ive already said and SEG said, check your exchangers. If warm you know coolant is atleast running, if not it would be air in the lines or a burnt up pump.

gunnin88 · 01-24-2013, 09:22 PM

Can i feel that by hand in the aluminum behind the seat? As far as multiple posts kinda whatever i guess i posted in wrong spot when i found right spot i reposted.

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Josh Kidner · 01-24-2013, 09:25 PM

Quote:

Originally Posted by gunnin88

Can i feel that by hand in the aluminum behind the seat? As far as multiple posts kinda whatever i guess i posted in wrong spot when i found right spot i reposted.

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Follow the coolent hoses under the tunnel you cant miss the exchangers. You can touch them,

gunnin88 · 01-24-2013, 10:53 PM

Thanks

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**smallengineguy** · 01-25-2013, 03:38 AM

Look under the seat where the track is. You'll see th long aluminum things. They will be warm to the touch.

gunnin88 · 01-25-2013, 11:44 AM

Great!! Working on it sunday. May have more questions then.

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gunnin88 · 01-27-2013, 10:12 PM

Nightmare!!! Have to replace one jug, the head, pistons and rings!! FML. Been blown up and patched together.

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**smallengineguy** · 01-28-2013, 03:43 AM

At least now it can be done right.

**kccats** · 01-28-2013, 06:54 AM

Send the jug and new piston to US Chrome in Wi they can weld and replate it for you! Why the head?

gunnin88 · 01-28-2013, 11:23 PM

Head is beat up pretty bad although i have been told i could still use it. It appears to have a new jug on right side the left side has deep groves. I found a nice used jug i am going to have both jugs honed i ordered a upper end rebuild kit from wiseco. Great compresion on rt side 120 only 60 on left side. I was told i am best off doing both even though comp is good on rt side

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