Coolant smell under boost

[Blkt6]

Just got my 87 Gn going after sitting in storage after 10 years. I noticed only under boost there is a slight coolant odor. No odor during normal light driving. Car idles and drives fine, no white smoke, coolant level (RM25 & water) is normal. No milky oil.
Any ideas before I commit to a head gasket change?

 

[No disintegrations]

most likely a blown head gasket. Sorry to say.

 

[No disintegrations]

most likely a blown head gasket. Sorry to say.

Do you have constant bubbles in the radiator while running the engine at idle? If so it's HG time.

 

[TurboTGuy]

Not really a boost issue,but put the car on a lift and check around the head bolts/studs, particularly on the driver side. They have a tendency to seep, especially when a car has sat for that long. Some "Cadillac Tabs" usually fixes that problem.

 

[Pronto]

I would look first at your radiator. Probably porous and restrictEd if it's the original.

 

[Chuck Leeper]

Any ideas before I commit to a head gasket change?

Ya, a leak down test.
A cooling system pressure test.
10 yrs sitting, it's a wonder there's anything left of that radiator. How about the heater core, the hot water valve? They part of the stinky issue?

 

[BEATAV8]

um... RMI25 and water? Is there any glycol in rhe motor?

 

[Blkt6]

Just switched over to RMI 25 and water when I changed the water pump. There might be a little glycol left in the motor. Was planning on doing another flush. Leak down test is next.

 

[EVIL]

Also check the radiator drain plug

D

 

[Chuck Leeper]

Just switched over to RMI 25 and water when I changed the water pump. There might be a little glycol left in the motor. Was planning on doing another flush. Leak down test is next.

When you did the pump, did you do the flush to include the heater core?
If it was turned off, there was little to no water going thru it.
It could be seeping the crud that is in it.

 

[NOONG]

I just went through this and went down the whole list like you are going through and after all that we found out it was the stupid heater control valve up by the firewall on the passenger side. $7 plastic part that died and was seeping. Good Luck, nothing worse than chasing gremlins.

 

[No disintegrations]

Why don't all of the above ideas cause a smell during normal driving? Only under boost?

A regular leak should smell all the time, not just boost.

 

[Chuck Leeper]

Why don't all of the above ideas cause a smell during normal driving? Only under boost?

A regular leak should smell all the time, not just boost.

Much higher engine compartment temp, more air flow, and the air intake is right where it's in the highest air psi area..Base of the windshield.
Also, if the h valve is leaking, and the foam seal around the pipes is MIA, the smell has an easy path to the driver.
Hiway Stars sells a real, metal Delco valve.