CraigFulton
1/2 ton status
Is there somewhere to look on the heads to ensure they are from a 400?
CK5
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76’ 400ci overheating bad
- Thread starter CraigFulton
- Start date
so thats how you change the oil on those super car's . . .
nice ride and blazer .
nice ride and blazer .
CraigFulton
1/2 ton status
That tear down was the result of changing the oil actually. The small foil from the oil container went into the dry dump oil tank. 10 hour oil change because of that mistake.
Cad
They could also be 350 heads that have been drilled out.
So even the casting number won't tell you for sure.
What is suspicious is that the issue occurred after the rebuild.
If the thermometer confirms an overheat situation, and the thermostat is open, and the heat is not coming from the tranny excessively.. then you would suspect the steam holes.
Casting number under valve cover.
They could also be 350 heads that have been drilled out.
So even the casting number won't tell you for sure.
What is suspicious is that the issue occurred after the rebuild.
If the thermometer confirms an overheat situation, and the thermostat is open, and the heat is not coming from the tranny excessively.. then you would suspect the steam holes.
CraigFulton
1/2 ton status
Thermostat definitely opens up.
I’m guessing removing the heads is an all day job. Pull the carb, distributor, exhaust, and intake. Then the heads come off? I guess I’d need intake, head, and exhaust gaskets?
Headed to harbor freight for infrared thermometer in a few.
I’m guessing removing the heads is an all day job. Pull the carb, distributor, exhaust, and intake. Then the heads come off? I guess I’d need intake, head, and exhaust gaskets?
Headed to harbor freight for infrared thermometer in a few.
CraigFulton
1/2 ton status
Racking my brain on this steam hole thing. Could the heat in that isolated area really have an affect on exhaust heat and vapor lock? It seems from reading up on this that the heat from steam vents is isolated to hot area around the cylinder walls that leads to cracking. Really hoping I get an answer from engine builder tomorrow, but can’t see how someone building engines for 30+ years messes that up.
It probably is not.
But you asked for ideas.
CraigFulton
1/2 ton status
I do appreciate the ideas. I have bad OCD so it tough fighting the urge to rip it apart right now.
You say it is "overheating".
Is that assessment based on the circa 1976 temp gauge?
Has it boiled over?
The next step is find out exactly what temp it is running.
Don't worry about anything else right now.
Is that assessment based on the circa 1976 temp gauge?
Has it boiled over?
The next step is find out exactly what temp it is running.
Don't worry about anything else right now.
CraigFulton
1/2 ton status
It has a brand new temp gauge in the dash from LMC. Ok. Here’s the moment of truth:
Lower radiator hose temp: 144
Upper hose: 154
Thermostat housing: 175 at the base
Exhaust manifold : 530 at the connection to pipe
Intake manifold at choke rod: 235 (took a pic because the paint is discovered here)
Transmission fluid lines at radiator: 135
Transmission line at trans near exhaust: 170-200
Exhaust near trans lines: 503
Mufflers: 270
Transmission pan in center: 135
Transmission pan near exhaust: 360 !!!
Fuel line going into carb: 185 (I think where the fuel line goes behind the alternator it’s blocked from fan and close to engine and getting it hot)
Carb bowl: 120
Fuel pump: 120
Fuel line half way back: 130
Transfer case: 127
Fuel tank: 103
Oil pan: 167
Passenger side radiator: 140
Drivers side radiator: 162
The temp on the he heads is all over depending if I’m near the valve cover or exhaust manifold. From 250-300.
Lay it on me!
Lower radiator hose temp: 144
Upper hose: 154
Thermostat housing: 175 at the base
Exhaust manifold : 530 at the connection to pipe
Intake manifold at choke rod: 235 (took a pic because the paint is discovered here)
Transmission fluid lines at radiator: 135
Transmission line at trans near exhaust: 170-200
Exhaust near trans lines: 503
Mufflers: 270
Transmission pan in center: 135
Transmission pan near exhaust: 360 !!!
Fuel line going into carb: 185 (I think where the fuel line goes behind the alternator it’s blocked from fan and close to engine and getting it hot)
Carb bowl: 120
Fuel pump: 120
Fuel line half way back: 130
Transfer case: 127
Fuel tank: 103
Oil pan: 167
Passenger side radiator: 140
Drivers side radiator: 162
The temp on the he heads is all over depending if I’m near the valve cover or exhaust manifold. From 250-300.
Lay it on me!
CraigFulton
1/2 ton status
This appears to be an area of concern.
CraigFulton
1/2 ton status
Drove the R8 at about 140mph. Came back and drove the K5 for 5 minutes and let it sit idle in the driveway for 10.
CraigFulton
1/2 ton status
It’s very close. About 40 degree cooler on driver side. Around 470.
CraigFulton
1/2 ton status
I’m losing my mind on this truck. You think I’m clear to put heat wrap and the EFI kit on it and go? I want to be able to drive this thing to Northern GA any time with issues. 500 miles on way.
I was wondering about what you drove because of trans temp.
If that is an issue then was 5min enough to tell?
And the exhaust temp on both sides was to see if maybe you have valves adjusted a little tight allowing combustion gasses/flame into the pipes.
Beyond that I guess I'm along for the ride to see what you find lol
If that is an issue then was 5min enough to tell?
And the exhaust temp on both sides was to see if maybe you have valves adjusted a little tight allowing combustion gasses/flame into the pipes.
Beyond that I guess I'm along for the ride to see what you find lol
CraigFulton
1/2 ton status
This is a fun ride to be on! Haha. I will get it really warmed up and get more temp readings. Ordering the exhaust wrap next. I’ll do that and the EFi all at once.
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