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Old 04-11-2020, 12:27 AM   #26
LuckyRabbit4
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Re: **cooling system issue**

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Originally Posted by Steeveedee View Post
If it is running smoothly and not overheating, it just may be coolant in the exhaust. Run it until it clears up. That may take awhile. I had it happen on a car of mine and I drove it about 30 miles before the water vapor calmed down.
I might try to do that and see what happens. Just afraid something is wrong and running it like that hurting it worse. I'll check compression tomorrow and see what that says. If ys all good I might just run it for a while
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Old 04-11-2020, 12:15 PM   #27
Steeveedee
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Re: **cooling system issue**

Smart move!
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Old 04-11-2020, 03:31 PM   #28
LuckyRabbit4
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Re: **cooling system issue**

I found that compression should be about 150psi in a 250 chevy.

Mine is: 130/120/150/120/120/120

I did see antifreeze on the 1st and 2nd plugs and unfortunately a little discoloration on the oil dipstick. I'm not sure why there is such a variation in the compression PSI if it's all suppose to be 150 like I've read.
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Old 04-11-2020, 03:39 PM   #29
LuckyRabbit4
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Re: **cooling system issue**

Could bad timing or setting the valves cause the compression to be off? I'm doing as much as I can on my own but starting to look like I need someone to take a look and diagnose this thing before I waste time on a warped head or something unfixable.

Timing and setting the valves are the only other things that I'm not 100% I've done right. Or maybe not close enough to perfect to make everything relatively smooth for now.
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Old 04-11-2020, 03:41 PM   #30
LuckyRabbit4
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Re: **cooling system issue**

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Originally Posted by LuckyRabbit4 View Post
I found that compression should be about 150psi in a 250 chevy.

Mine is: 130/120/150/120/120/120

I did see antifreeze on the 1st and 2nd plugs and unfortunately a little discoloration on the oil dipstick. I'm not sure why there is such a variation in the compression PSI if it's all suppose to be 150 like I've read.
I just found another forum saying that the compression should about 130 from the manual. So why is the 3rd piston at 150? clog? valves too tight and can't escape the cylinder? just bad timing?
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Old 04-11-2020, 04:05 PM   #31
Steeveedee
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Re: **cooling system issue**

Could be carbon buildup. Your compression numbers aren't the greatest, but about what I'd expect to see in an old engine. I'd expect to see something like 150 psi on a new/rebuilt engine. It looks like at least the head is going to have to come off for either a gasket replacement or possibly a valve job, plus draining the contaminated oil.
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Old 04-11-2020, 04:08 PM   #32
LuckyRabbit4
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Re: **cooling system issue**

well... I've had the truck 2 years and hasn't seen the road for more than about 30 minutes. I'll look into getting a new gasket and probably intake while i'm at it. Valves are terrible to set. Not sure I've even done that right yet. I'll drop the oil out this weekend and start the gasket replacement all over again.
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Old 04-15-2020, 02:14 PM   #33
Ken Cook
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Re: **cooling system issue**

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I finally got the 4.1 250 back together after blowing a head gasket.
Did you bring the head to a machine shop to have it checked?
If you pull it back off, you should have it checked before you re-install it.
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Old 04-15-2020, 02:56 PM   #34
LuckyRabbit4
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Re: **cooling system issue**

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Did you bring the head to a machine shop to have it checked?
If you pull it back off, you should have it checked before you re-install it.
My dad is an engineer with all that stuff. Said the head checked out. Maybe the block has some issues. Torqued the head bolts to specific but maybe I missed something? Hard to believe it's broke before running it.
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