Gen2 H6 thermostat removal, problem with bolts check

H6'ers out there, my #1 worry about trying some magic head-gasket elixir is pulling the thermostat, are the bolts gonna snap?

They have been untouched for probably 200,000 miles.

Dave

I'd try using a propane torch to warm-up the bolts, then spray them with a penetrant (Kroil, PB Blaster or even home-made ATF/Acetone 50:50 - careful not to catch fire!)

 

When the bolt cools from the spray - maybe some liquid will be pulled in. Then, if you have no luck budging the bolt, try tightening slightly first, then re-try removal.

 

but, I really don't see how Blue Devil can work from the coolant side of this type of HG leak.

I wouldn't think so - use a 6 point socket. are yours really rusty?

give it a try and see if they start to budge or if they're tight or not?

Edited May 23, 20169 yr by grossgary

1LT, I'm on the fence about trying the magic schmutz, I plan on actually calling them this week.

 

Gary, haven't actually tried them yet, just fishing to see if they have a 'rep'.

Mine came right out...


It sounded like you're already considering scrapping the car/engine if it does in fact need head gaskets. Start with the Subaru coolant conditioner, it's like $3. If it still runs hot under load etc., then you have nothing to loose.

 

 

I've heard nothing but good things about Blue Devil from those who have used it (You can always find negative reviews from people who haven't...). I found a YouTube video awhile ago where a guy did a chemical block test immediately before and after treatment, and the results there were night and day. Then I found in his later videos, him retesting the same car tens of thousands of miles later and it still passed. Search for it, it's better than most Youtube videos.

It's not overheating at all now, and not burning any coolant.

If I didn't know it had a blown head gasket (blip, blip, blip of bubbles out the overflow hose), I'd never suspect it.

 

I have been using the subaru additive for many years.

I'm wondering if the stuff would actually work better if the leak were worse...

Then I say just drive it...

two of them i've seen exhibited overheating only in the summer, one would only do it with the A/C on in the summer and drove two years before it got bad, but the first year of issues those two cars would only have problems in the summer. 

those two both started out really slow and took about 2 years to get to the point they were overheating and/or using significant amounts of coolant.  so if you go easy on it maybe you'll limp it along awhile. 

 

that would be hard to believe if someone told me that and i didn't see it with my eyes - i can concoct scenarios to make it sound plausible..maybe...but it doesn't seem immediately logical that 90 degree ambient temps make any difference to a thermostatically controlled engine that's 200+ degrees. .

If the thermostat maxxes out in flow, from there the coolant temp has to start going higher, maybe when there are unpurged (and replenishing) gas pockets the cooling is slightly impeded- and the metal touching gas gets a little hotter. Maybe even hot enough for local boiling?

 

If the coolant gets hotter, the heat transfer from the metal block/head must slow down as the difference is smaller, all it takes is for a few factors to avalanche the whole thing into overheat territory.

Probably not a lot of built-in spare capacity.