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I like the Stant caps with the pressure relief valve. You can test the expansion tank function manually. You can also test for fluid interchange by draining and rinsing the expansion hose, then refilling to the cold line with distilled water (only). That cap looks to have the vacuum valve, but also a bunch of gel/gunk, like someone had used leak stop in the past. I'd get a new cap
That is filled to the tippy top. did some spill when you opened it? Otherwise, it might leak from the expansion hose.
Mine dribbles from the lower rad hose, but only when cold, so check those clamps, too.
I like the Stant caps with the pressure relief valve. You can test the expansion tank function manually. You can also test for fluid interchange by draining and rinsing the expansion hose, then refilling to the cold line with distilled water (only). That cap looks to have the vacuum valve, but also a bunch of gel/gunk, like someone had used leak stop in the past. I'd get a new cap
That is filled to the tippy top. did some spill when you opened it? Otherwise, it might leak from the expansion hose.
Mine dribbles from the lower rad hose, but only when cold, so check those clamps, too.
Yea a good bit spilled out when I removed the cap. I’m gonna test this cap. How do I test the expansion tank?
What I meant is that by filling the expansion tank with distilled water, you will see the color change if the tank is being used. If the water turns green, then returns to the same level, you can be assured that the new cap is working in both directions. You can also find leaks in the tank (and hose) with them off the car.
All of this pressure discussion is good and necessary to get a well-functioning cooling system but isn't fixing the leaking issue.
If the car is operational, buy 3-4 cans of spray degreaser, run it over to a pressure wash car wash and try to clean off the caked grease and oil on the underside of the block and steering linkage. As to not being able to see where the leak is coming from, do you have a cheap bore scope that you can connect to your phone to snake down between components to spot the leak?
Back to the overflow/expansion tank, I'd pull the hose off the radiator that goes to the expansion tank and see if you can blow air through it. Could well be constricted... Seems to me you may be in need of a complete coolant system check and flush but need to find that source of dripping coolant first.
All of this pressure discussion is good and necessary to get a well-functioning cooling system but isn't fixing the leaking issue.
If the car is operational, buy 3-4 cans of spray degreaser, run it over to a pressure wash car wash and try to clean off the caked grease and oil on the underside of the block and steering linkage. As to not being able to see where the leak is coming from, do you have a cheap bore scope that you can connect to your phone to snake down between components to spot the leak?
Back to the overflow/expansion tank, I'd pull the hose off the radiator that goes to the expansion tank and see if you can blow air through it. Could well be constricted... Seems to me you may be in need of a complete coolant system check and flush but need to find that source of dripping coolant first.
I do have a bore scope. Ill clean off this sludge first. Its been bothering me for too long.
I wanna avoid sensors and connectors though. Where is the coolant temp sensor and baro sensor, so I can avoid them?
I wanna avoid sensors and connectors though. Where is the coolant temp sensor and baro sensor?
Having NO sensors on my Corvettes, I'll have to tap out on that. I've power washed modern (computerized) car engines without trouble plus you're focused on cleaning the bottom side that typically has fewer electrical components.
you need a new cap.. as mentioned
- make sure overflow hose open..
- verify radiator openings are fairly open.. maybe a few better shots best you can to see how clogged it is.
still does not add up with all that coolant loss volume why or how level same.. or does not move.. it should show up fairly fast..
thank for pics!
you need a new cap.. as mentioned
- make sure overflow hose open..
- verify radiator openings are fairly open.. maybe a few better shots best you can to see how clogged it is.
still does not add up with all that coolant loss volume why or how level same.. or does not move.. it should show up fairly fast..
thank for pics!
Yea that's a sizable amount of coolant, I should see it missing somewhere. The engine temp has always been less than 200 according to the gauge.
Radiator openings?
Can I keep the cap off and run the engine? would that show anything? Should I see coolant flow into the reservoir?
Also where's the coolant temp sensor?
Also, what do you mean by it should draw coolant back if working?[/QUOTE]
The radiator cap has a vent/vacuum valve in it. What this does is; (Vent function) any air within the radiator will be pushed out the overflow line to the coolant reservoir when the coolant expands due to heating. And (Vacuum function) the radiator cap will allow coolant to enter the radiator when the coolant starts to cool or contract. And the radiator cap will only push coolant to the reservoir when the coolant pressure exceeds the rating (usually 15-18 psi) of the cap. (This is the spring contained within the cap)
Sounds like your vent/ vacuum valve in the cap may be bad. Unfortunately, you can't test this function with a "pressure tester". Get another cap and try it, it's the only way to know.
You could be losing coolant without seeing a drop in the level of the reservoir, but your radiator level will be low. Hence the explanation above. Do not open the cap while hot to check, you will get scalded.
Also, what do you mean by it should draw coolant back if working?
The radiator cap has a vent/vacuum valve in it. What this does is; (Vent function) any air within the radiator will be pushed out the overflow line to the coolant reservoir when the coolant expands due to heating. And (Vacuum function) the radiator cap will allow coolant to enter the radiator when the coolant starts to cool or contract. And the radiator cap will only push coolant to the reservoir when the coolant pressure exceeds the rating (usually 15-18 psi) of the cap. (This is the spring contained within the cap)
Sounds like your vent/ vacuum valve in the cap may be bad. Unfortunately, you can't test this function with a "pressure tester". Get another cap and try it, it's the only way to know.
You could be losing coolant without seeing a drop in the level of the reservoir, but your radiator level will be low. Hence the explanation above. Do not open the cap while hot to check, you will get scalded.[/QUOTE]
but the level in the radiator is good too, according to the level when removing the cap? (see pic).
Should I be able to see coolant flowing back into the reservoir?
radiator openings..the openings of the fins in side the radiator.. some crap ok but do not want too much restriction on an old radiator to keep cool.
you can keep cap off but wont tell you much unless air or other weird things happen..blow through the overflow hose to be sure clear
also i like the pressure tester.. you may rent for free at auto store?
I was thinking of pressure testing too. But that won't be today. Not sure if I can rent one for free. Ill look for the radiator openings. Also, note, cant confirm this for sure, but when I removed the radiator cap, a bit of coolant came out. I put the cap back, checked the reservoir, and the level dropped slightly. Does that mean the overflow hose is good?
I was thinking of pressure testing too. But that won't be today. Not sure if I can rent one for free. Ill look for the radiator openings. Also, note, cant confirm this for sure, but when I removed the radiator cap, a bit of coolant came out. I put the cap back, checked the reservoir, and the level dropped slightly. Does that mean the overflow hose is good?
it will only lower in reservoir when sealed and coolant contracts and draws it in radiator
Ok. News. Replaced with a new 16lbs thermostat (according to auto zone thats my spec?) I did a test run today, in my garage. 2 mins in leak appeared. Same volume as yesterday. I tried to trace the cause, and I think its water pump? Got some pics, and some long vids but I cant upload anything over 20mbs so ill save it unless y'all want em. Pics are below.
Also I know I said I was gonna clean under engine today, but I didn't have enough time, sorry. Ill try to do it tomorrow
The second to the last picture also shows some pink liquid which looks to be coming from the trans cooling lines based on the location. Whatever you do plan on replacing all the hoses, they look old and carry the life blood of your engine. I recently had a small coolant leak, the heater hose coming off the pump had a small hole that dripped down on and in the frame, and came out by the passenger area. Looked just like a heater core issue. After I replaced that, I had a small leak in the front of the engine that looked like the water pump, it was actually the fitting the heater hose goes on the pump. My point is, leaks can be deceiving and with all that gunk on your engine, everything looks wet. Clean it off but I would not use a pressure washer around 40 year old wiring and connectors. Might take a couple of tries but soak it with one of those spray cleaners and hose it off with a strong garden hose. Your pump does look like the issue but I'd want to be sure before tearing into it.
The second to the last picture also shows some pink liquid which looks to be coming from the trans cooling lines based on the location. Whatever you do plan on replacing all the hoses, they look old and carry the life blood of your engine. I recently had a small coolant leak, the heater hose coming off the pump had a small hole that dripped down on and in the frame, and came out by the passenger area. Looked just like a heater core issue. After I replaced that, I had a small leak in the front of the engine that looked like the water pump, it was actually the fitting the heater hose goes on the pump. My point is, leaks can be deceiving and with all that gunk on your engine, everything looks wet. Clean it off but I would not use a pressure washer around 40 year old wiring and connectors. Might take a couple of tries but soak it with one of those spray cleaners and hose it off with a strong garden hose. Your pump does look like the issue but I'd want to be sure before tearing into it.
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thanks. My thought process is if the pump is original, I’m gonna have to replace that anyway (130k miles) but I’m not sure if it’s original or not.
it will only lower in reservoir when sealed and coolant contracts and draws it in radiator
so at this point, I’m at a crossroads. I’m not sure if that pump is original, if it is i wanna replace it. If not I wanna replace the gaskets. Does anyone know how I can tell if it’s original?
My experience is that failed water pumps don't tend to send out a stream of coolant but seep through the weep hole under the nose and/or rattle like the dickens. You should be able to judge the bearing fitness by trying to wobble the belt pulley for movement and listening to the pump at idle using a 2' length of heater hose between your ear and the pump housing. Should be just a whirring sound and no clicking or growling/grinding.
I think you more than likely have a split hose, but could be a cracked water pump housing too. I had a water pump rebuilt (correct casting # and date) and upon installation discovered an invisible crack in the casting that opened when the metal warmed up and began spraying out coolant. It was in the right-hand port about midway between the block mounting flange and the bearing nose, so I'm not sure the rebuild guy could have caused it... to metal recycling it went.
Oops, didn't answer your question about originality.
Odds are that it's a replacement as water pumps didn't generally last 130k miles in the old days. If you get the cast number and date code from it, that will answer your question. The parts counter pump is #6258551 - not sure if that's the same as assembly line pump or a service replacement. Since it sounds like you're concerned about reliability, just replace what's there anyway since they aren't expensive (~$70) and you'll know for sure it is good to go.
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