- Thread starter
- #21
Sorry, I am a bit confused. What did he do that fixed it? I will try it right now.
...and like that, it's down (1 Viewer)
- Thread starter ANGLICO0861
- Start date
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If your coolant overflow isn’t bubbling and/or you don’t have white exhaust smoke:
Fill via radiator cap... not via coolant overflow. He was on the road. So, in a pinch he refilled a radiator with the engine at operating temperature and had to take steps to prevent hot coolant from spaying him (opened the cap with a towel or rag). With your truck cold, top it off via the radiator cap. Start up the truck and let it get to operating temperature. Stop the engine, allow to cool, add coolant via the radiator cap, repeat until the radiator is filled up to the opening of the cap.
Fill via radiator cap... not via coolant overflow. He was on the road. So, in a pinch he refilled a radiator with the engine at operating temperature and had to take steps to prevent hot coolant from spaying him (opened the cap with a towel or rag). With your truck cold, top it off via the radiator cap. Start up the truck and let it get to operating temperature. Stop the engine, allow to cool, add coolant via the radiator cap, repeat until the radiator is filled up to the opening of the cap.
- Thread starter
- #23
Ok got it. Will give that a try.
- Thread starter
- #24
Adding to the mystery, before the engine warms up, I am starting to get some hesitation and backfiring from the carb. I am starting to wonder if the 2 problems may be related. Once up to temp, it runs great and pulls just fine. I sprayed some started fluid around the carb and intake and didn't notice any change in rpm from the motor, so it doesn't seem to be a vacuum leak in the intake manifold/carb.
I have an 81 emission manual... do you want to borrow it to make sure everything is hooked up correctly? Also, emissions lines may be cracked/dried out.
- Thread starter
- #26
Thank you, but I dont think it would be much help. A previous owner desmogged and put a Weber 38 and headers on it.
- Thread starter
- #27
Tried getting it warm and cooling it down several cycles. Fluid stayed topped off in the radiator through each cycle
I am going to take it for a drive on the parkway and see how it does.
I am going to take it for a drive on the parkway and see how it does.
This would be done with the radiator fill neck facing up hill, per se'. Maybe revving motor at times. With the cap off as long as possible, keep a pan underneath.
(Maybe on car ramps would aid in the burping process)
You are sure the thermostat is operating correctly? I don't recall if they can be installed upside down since its been so long since I replaced one.
The water pump is an un known. Have you taken the rad out to inspect it? I.e. look for crud at the lower end that may indicate potential blockage? When you flushed? Did you do a chemical flush?
The water pump is an un known. Have you taken the rad out to inspect it? I.e. look for crud at the lower end that may indicate potential blockage? When you flushed? Did you do a chemical flush?
- Thread starter
- #30
I
I should say that I know that when the engine comes up to temperature when stationary that the thermostat will open. It might not be opening correctly when the engine is at high sustained rpms though. Next is pulling the radiator out, I really think it is the most likely suspect. If there were a blockage in the block I would expect it to overheat more frequently than just on the highway. I just did an hour at 45-50 mph on the gw parkway and the needle didn't budge. But more than 5-10 minutes above 50 and the temp goes up so fast it is tough to get safely off the highway before it boils over. I figure I will do the radiator, thermostat( while I am at it)and all the hoses first. If that doesn't work a new water pump. If all that doesn't work I am truly at a loss and there is likely a head gasket issue or something more serious.
I am hoping the backfiring and sputtering prior to warm up is just a simple carb set up issue and unrelated to the cooling issue
Compression test should be your next step before pulling parts.
It can tell you if you may have a valve issue like a stuck valve or blown or even an HG issue.
It can tell you if you may have a valve issue like a stuck valve or blown or even an HG issue.
HG's issues are not common on 2fs especially if they aren't run hard.
- Thread starter
- #33
Good call. Yep, will do that tomorrow
I’m thinking about possible reasons and it might worth considering... the fluid coupler and the fan, can you spin the water pump fan and determine if there’s any sort of resistance?
OTRAMM
Supporting Vendor
With backfiring and sputtering, you may be running lean. Running lean means running hot. Also check the timing to make sure you aren't overly advanced. That could make you run hot as well and would be worse moving faster under load.
- Thread starter
- #36
Thank you, I have a Weber so I can adjust that pretty easily. I will check timing and compression this afternoon.
OTRAMM
Supporting Vendor
I'd check very closely for vacuum leaks before messing with carb setting.
iptman
SILVER Star
This is the smoker I bought recently. Worked great to track down a evap leak caused by a mouse.
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This! If you didn't have headers, I was going to suggest a very strange issue that caused my overheating years ago at highway speed. And that was caused by the exhaust gas diverter flap thing becoming unpinned and blocking my exhaust manifold. Also, to answer Stump's question. Yes you can most definitely install the thermostat upside down. The PO of my 55 did just that. It crushes the thermostat slightly, but it will fit upside down.
Yeah that diverter cracked my intake manifold, causing a weird vacuum leak that took a really long time to diagnose.
