Excuse me Slantsixdan, I did not intend to aggravate you.

I have followed the advice given including:
Testing the thermostst
Testing the gauge with another
Removing the freeze plugs and cleaning the block
After finding the suds, I had the head magnafluxed, and replaced the seats with hardened seats as the old ones were worn out, Replaced the gasket.
Reloacated the radaitor for air flow


I asked the question about long period of time running because i wanted to know if this engine runs hot at this rpm.(3200rpm)

Thanks, I appreciated the advice given at this site.

You didn't aggravate me. You've just kinda run out of "print on screen" solutions; something is blowing bubbles in your cooling system and now you have to do the diagnosis work to figure out what it is.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

In the Puget Sound region when it gets 100 degrees the slant will run at what ever stat you put in it. I run a 195 stat and it will run right at 180 during cruising on the freeway and at stop lights it will still stay 185/190. If it sets longer the electric fan will kick on at 200 degrees, but the radiator tank always runs hotter than the motor. I never see the block running very hot.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

i noticed you installed hardened valve seats. when i had this done on one of my heads the seat insert pocket cut into the water jacket on one cylinder and a screwdriver could punch through the other pockets they were so thin. if this is the case on yours thats where the gas could be coming from.

Thanks for the replies, the overheating was occuring before the seat replacements.

I cant find a local shop with a combustion gas detector, so Im thinking of purcasing one.
The machine shop that magnafluxed the head said there were no cracks, Im starting to second think the machine shop.
Wouldnt there be water in the exhaust(I had a coolant pressure test done and didnt see any water in the exhaust)
Maybe I should start to look for another head
The cooling system does not boil over or create excessive pressure. It just runs hotter than I Like it.

The bubbles indicate a head gasket leak which could be forcing compressed exhaust gasses into the cooling system, then creating steam, which causes the hotter than normal readings. It can be so slight that it may not show up in the tail pipe once warmed up. It may be a slight crack or deformity in the head gasket it self less than an inch long.

What are the head bolts torqued to?
Are any under torque?
A simple check may indicate a under spec bolt which may be wear it is leaking.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Today I removed the fan belt and brought the ehgine to 3,000 rpm and bubbles appeared.
Looks like I need another head and another machine shop.

So did you get another head/machine shop?
Was this issue ever taken care of?

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1969-1/2 Dodge Super Bee A12 (440 Six Pack, 4-spd, Dana 60)
1974 Plymouth Duster 360 (4-spd, 8.75")
1973 Plymouth Duster (225, auto, 8.25")
2001 Dodge Ram 1500 QC 2wd (5.9L, auto, Dana 60)