Coolant flow obstructed?

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Cloren10
Posts: 8
Joined: Mon Dec 07, 2020 3:36 pm
Car: 1990 Nissan 240SX

Coolant flow obstructed?

Postby Cloren10 » Thu Aug 26, 2021 4:22 pm

This car never quits fighting me when all I'm trying to do is bring it back to life :frown:

So took the head off, had it surfaced, and when I was scraping the old gasket off of the block, one of the small blue shop towel pieces I had fell into oblivion into a coolant channel in the block, right before the coolant sends out to the heater core. Now I poured water down said hole to try to flush it out but no luck. It was pretty small, figured NBD.

Fast forward, get it all back together and I run it. Now it runs for a good 2 or 3 mins and the car starts smoking pretty damn bad out of the exhaust manifold side/area. I thought it was an exhaust leak (maybe it still is?) But noticed that it gets much worse the longer the engine runs.

Then it started to dawn on me that maybe it's just overheating, despite the temp gauge (which I tested and it worked before I reinstalled the head) keeps showing all the way cold. Popped off the radiator cap, fluid is room temp despite the car running at 1750 rpm for a good 3 to 5 mins total.

Does this sound more like an air in the cooling system issue or did the small piece of shop rag come back to haunt me and block the thermostat opening or the coolant flow?

Thank you ahead of time!

CL


User avatar
VStar650CL
Posts: 2725
Joined: Thu Nov 12, 2020 1:25 pm
Car: 2013 Nissan Altima 2.5 SL
2004 Nissan Altima 2.5 S

Re: Coolant flow obstructed?

Postby VStar650CL » Thu Aug 26, 2021 4:55 pm

Sounds like it's airbound. That's also the probable reason for no temp reading, the sender is usually located in or near the 'stat housing right where the bubble will be.

Cloren10
Posts: 8
Joined: Mon Dec 07, 2020 3:36 pm
Car: 1990 Nissan 240SX

Re: Coolant flow obstructed?

Postby Cloren10 » Mon Sep 06, 2021 10:13 am

That worked! Thank you very much!!

CL

User avatar
VStar650CL
Posts: 2725
Joined: Thu Nov 12, 2020 1:25 pm
Car: 2013 Nissan Altima 2.5 SL
2004 Nissan Altima 2.5 S

Re: Coolant flow obstructed?

Postby VStar650CL » Mon Sep 06, 2021 10:51 am

You're most welcome. Happy motoring!


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