Pressure in cooling sys. and blow-by from oil cap
11-11-2013, 11:12 AM
#21
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You might have an exhaust-to-coolant leak. You can test with this:
(I've never tried it myself). Most likely cause of such a leak is through the head gasket, but a crack in the head itself can do it.
11-11-2013, 08:27 PM
#22
The correct radiator cap helped and was workong for a while but... It has been almost a year and i am loosing coolant again. Very much the same way as described in the first post. About a liter per week of driving.
I found a thread where another truck has very similar symptoms:
https://www.yotatech.com/forums/f120...gasket-159309/
I start my truck when cold with hood open. The coolant hoses firm right up and the tube in the overflow starts bubbling. Not a lot but a slow steady stream of bubbles. Overflow tank smells of exhaust inside.
I turn off the motor and open the radiator cap (still cool) and the pressure that was in the coolant system dumps in to the overflow tank. Both the radiator and the overflow tank smell of exhaust fumes.
I just thought i'd mention it because this is a subtle set o' symptoms that i have not read much of here at YotaTech.
Kirk
I found a thread where another truck has very similar symptoms:
https://www.yotatech.com/forums/f120...gasket-159309/
I start my truck when cold with hood open. The coolant hoses firm right up and the tube in the overflow starts bubbling. Not a lot but a slow steady stream of bubbles. Overflow tank smells of exhaust inside.
I turn off the motor and open the radiator cap (still cool) and the pressure that was in the coolant system dumps in to the overflow tank. Both the radiator and the overflow tank smell of exhaust fumes.
I just thought i'd mention it because this is a subtle set o' symptoms that i have not read much of here at YotaTech.
Kirk
You might have an exhaust-to-coolant leak. You can test with this: Amazon.com: Lisle 75500 Combustion Leak Detector: Automotive (I've never tried it myself). Most likely cause of such a leak is through the head gasket, but a crack in the head itself can do it.
I did not have milkshake, but earlier on, the coolant would overflow into reserve tank. At first shop owner and I thought pressure was from boiling over
because of overheating.
Later on... while engine was cold with radiator cap off, as soon as I started engine, coolant would well up and I'd see bubbles come up. The only possible cause of this pressurization of cooling system while engine is cold that I can think of is exhaust leaking into cooling system.
Shop owner confirmed with hydro-carbon test.
At this point, I also noticed substantially more moisture (splashing, not dripping) out of exhaust pipe, and hard-starting- when there's no more compression, coolant may be pushed back into one or more cylinder(s)
11-12-2013, 08:03 AM
#23
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I hate to be bearer of bad news (which I experienced), but I'm with Scope103 &thedrewski86.
I did not have milkshake, but earlier on, the coolant would overflow into reserve tank. At first shop owner and I thought pressure was from boiling over
because of overheating.
Later on... while engine was cold with radiator cap off, as soon as I started engine, coolant would well up and I'd see bubbles come up. The only possible cause of this pressurization of cooling system while engine is cold that I can think of is exhaust leaking into cooling system.
Shop owner confirmed with hydro-carbon test.
At this point, I also noticed substantially more moisture (splashing, not dripping) out of exhaust pipe, and hard-starting- when there's no more compression, coolant may be pushed back into one or more cylinder(s)
I did not have milkshake, but earlier on, the coolant would overflow into reserve tank. At first shop owner and I thought pressure was from boiling over
because of overheating.
Later on... while engine was cold with radiator cap off, as soon as I started engine, coolant would well up and I'd see bubbles come up. The only possible cause of this pressurization of cooling system while engine is cold that I can think of is exhaust leaking into cooling system.
Shop owner confirmed with hydro-carbon test.
At this point, I also noticed substantially more moisture (splashing, not dripping) out of exhaust pipe, and hard-starting- when there's no more compression, coolant may be pushed back into one or more cylinder(s)
Im pretty sure the exhaust is leaking in to the cooling system as I can not get past the smell of the pressure/bubbles in the rad. or the OF tank.
Was your problem the head gasket, crack in the head or block?
kirk
11-12-2013, 09:10 AM
#24
Exactly my symptoms. Blown HG. Since truck already has 185K miles, I decided to have full rebuild. I was going to buy re-built from 22RE Performance in Chico, CA, but its leadtime is 10-12 weeks. Then, a local shop was recommended to me by an office mate. So far so good. I can feel more power from the engine, too.
11-12-2013, 05:15 PM
#25
Its been a couple of days with the new rad cap (13psi) and the trucks symptoms have disappeared!! Its now holding coolant and it took a little from the overflow tank. So it seems to be working well.
I am so glad! What a releif. Now i can plan an overhaul at a reasonable time. But its running great.
I am so glad! What a releif. Now i can plan an overhaul at a reasonable time. But its running great.
11-14-2013, 05:50 AM
#26
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Thanks Wallytoo
No, the plan did not happen. i'm not prepared but i have my 2wd to get me by and my neighbor is allowing me to use their garage for the winter.
No, the plan did not happen. i'm not prepared but i have my 2wd to get me by and my neighbor is allowing me to use their garage for the winter.
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