Sourcing Coolant Leaks

[heyitsrama]

So its probably a head gasket, but i just wanted to ask around.

My cars been sitting for a bout a year; ive been getting it back up and running after replacing the heater core....

I noticed yesterday when i was idling the car for about 20-30min there was a good amount of thin white smoke coming out of the exhaust; smelt more of fuel

my initial thought was that there could have been condensation build up from sitting for so long, no biggie lets just warm it up, and drive it. After a certain amount of time it stopped too, which was a good sign.

Today when i was draining the coolant upon removing the rad cap, i stuck my finger in it, and realized there was little to no coolant in the rad; so i removed the plugs and Cylinders 1-3 have carbon on the pistons, 4-6 have clean pistons with fouled plugs; which makes me think coolant in the cylinders....

But why 4-6? its a L26 block with a N42 head. An early e46 manifold with a 4 screw carb;

I changed the oil, there was no water in the oil (ran the car for 3-4 min before changing)

I realize now that i think about it the water gauge never moved, i figured there was a little corrosion on the wire, it might be that, but perhaps the coolant level was too low.....

I supposed a leakdown test will give me more information.

Could this be from a leak in the manifold runner?

[madkaw]

It’s typical for #5 to blow the HG . Go get a coolant pressure checker from a local parts store and do a pressure check

[heyitsrama]

18 hours ago, madkaw said:

It’s typical for #5 to blow the HG . Go get a coolant pressure checker from a local parts store and do a pressure check

It’s been raining all day I did manage to refill the radiator, and watched it burp. I’ll test out the pressure tomorrow.

i would think it would run really rough, but it’s pretty smooth... 

[madkaw]

Coolant pressure test should really pinpoint the issue . Watch your pressure as the engine runs . If it starts to rise , start pulling spark plug wires one at a time until you find the one that stops the pressure from rising . 

[heyitsrama]

7 hours ago, madkaw said:

Coolant pressure test should really pinpoint the issue . Watch your pressure as the engine runs . If it starts to rise , start pulling spark plug wires one at a time until you find the one that stops the pressure from rising . 

I located a leak at the thermostat housing, I think that due to a damaged surface the radiator hose is not able to get a good seal.

 

 

after repairing this I’ll continue with another pressure test.

theres only one local guy on Craigslist with a thermostat outlet.

 

thanks for your input @madkaw appreciate you. ? 

[Patcon]

Yeah...

That's not going to seal!

[madkaw]

You can buy them new pretty cheap 

[heyitsrama]

3 hours ago, madkaw said:

You can buy them new pretty cheap 

I grabbed one local,the guy who sold it to me used to have a 71. Its in pretty good condition! Upper, Lower, with a 190*f nissan thermostat $25

he was telling me about this pinhole that formed in his intake manifold coolant channel that was causing white smoke in the exhaust..... was in a old datsun pickup. shall do the test tomorrow in the morning.

Anyone have opinions of paper gaksets vs RTV//HondaBond?

[madkaw]

Paper gasket or RTV gasket maker. Just clean both surfaces really well

[heyitsrama]

29 minutes ago, madkaw said:

Paper gasket or RTV gasket maker. Just clean both surfaces really well

been working on the car all day, i replaced both the upper and lower thermostat housing, the new lower had to bypass the intake manifold because it was plugged off. plugged off the connector that goes near the fuel filter. Little to no smoke at startup, drove the car around for a couple miles, pulls pretty good, might need a carb tune...

cylinders 4-5-6 were all carboned up, which sounds like there *might* be a leak in the intake.....

Still need to do go to my buddies place and do a leakdown test to make sure.  Cooling system holds 10psi of pressure.