Well I got my new radiator shipped in today from Rock Auto with new Knock Sensors as well. I went to remove my old knock sensors this evening with a 22mm socket and got the drivers side out fine with a little effort. I am confused though because no coolant came out? Some should have correct? I was expecting it to come gushing out like some have said. Could it be that blocked up that something was clogging the hole? I did not have room for the car in my shop so it was outside and it was getting dark and had limited lighting so I could not tell. The sensor had some fluid on the tip I could see but that is all, just wet. I will get a better view tomorrow.
When I went to remove the passenger side Knock Sensor it is just spinning. I have a good bite on it and the head is just turning within the sensor. I have heard some say they have had issues with this as well. Should I try to get a wire welder in there and tack it back and try to remove it or what is my best option? I thought about trying a chisel to see if I could get some bite on it but I am afraid I will make it worse. Should I just let it go and forget about it? I would like to get it out and do it correctly especially since I have new knock sensors and a new radiator.
Any helpful tips would be greatly appreciated. As usual if there is going to be problems it will be with me. LOL.
Also wanted to ask how I can flush it from the top side? I am sure this is a stupid question but I had the thermostat out should I not be able to run water down the water pump hole and it flush through and out the knock sensor that is out on the drivers side or would the water pump have to be pumping or pulled off the motor for it to flow through?
Any suggestions on what my next options should be? I am truly at a loss and very frustrated.
On th side that you got 1 KS removed, there is most likely a lot of crud blocking the hole. Take a small screwdriver or awl and poke it in the block which should open up and allow coolant to run out.
On the passenger side KS, sounds like the lid of the KS has separated from the body. It does not take much torque on the KS for this to happen. It may be real helpful to take a few extra minutes and remove the starter to gain some valuable working room in this area. Then as you suggested you could try to tack weld the lid back to the body of the KS. If you do this, try to turn the sensor in clockwise, just a little first and then back it out. At the first sign of resistance, move it back in clockwise and then back it out a little further. Your fighting with the junk in the system along with the threads in the block to remove the KS.
If all else fails, then it's time to get creative with a pair of vice grips or similar on the body of the KS. At this point, I would do whatever you can to get the old KS out of there. It is probably no good now that the lid has separated from the body. When reinstalling, there should already be sealer on the threads. DO NOT use Teflon tape or other sealant as this will affect it reading properly. Install torque on these is very low too.....I believe it's only 14' lbs.
To flush the block, yes filling from the WP Tstat housing should work. You just need to block off the heater core ports and rad port to fill the block. I assume these are all disconnected anyway for flushing. I like to block off the KS ports on the block to let the block fill and then remove the KS to allow it to FLuuuuush real good. Do this a few times til the water appears clear. Once done refill with a 50/50 mix of distilled water and coolant. A complete flush will take about 2 gallons of H2o and 2 gallons of coolant.
I had the block drain plug hole do that on my 83 GM V8 driver side .. back then no KS just a pipe plug. when I stuck a screw driver in the hole the block drained and had casting sand in it which caused the blockage.
on my 96 I never had any issues removing the KS but I removed them when the vehicle was 3 yrs old. also I am the only person that's works on it.
over torquing maybe the problem on why it broke. using various tools you should get it out .
I use permatex MACHINE thread sealant on the threads and torque to about 10 ft lbs being careful NOT to shock/drop the sensor OR bang hit it...
this type sealant is basically paint ..will not effect sensor operation in any way and no leaks. using a round pipe brush work the block threads so clean less chance of leak.
on coolant I use 2.5 gallons of antifreeze and 1.5 gallons of distilled water. it may take a extra QT if you blow out the heater core which it what I do every time this is done.
Yep, just did mine. Barely inserting a small screwdriver into the DS had it gushing. The PS side came out easy for me, but there was nearly no water left at that point. A cup maybe. Doubt if even a pint.
If you however want to tackle it, you may want to try a plumbing wrench. Name escapes me at the moment, but it's a spring loaded jaw that's use to get the faucet nuts at the back of a sink. Acts like a pipe wrench, self locking, but the handle is parallel like the socket extension would be. And the end has a T bar.
Interesting! Has anyone tried a Basin Wrench on this before and had it work? Would I be better off trying that first before welding it? Thanks for the info!
Have not as I've been fortunate to get them out with a socket/ratchet. As you probably know laying under the car and looking at the sensor, having a wrench that has a flex head could be very helpful. The angle of the block where the sensor is compared to the angle of the oil pan, does not make it easy to attack the KS housing from the side. A pipe wrench that does not flex could make this difficult from the underside of the car. Maybe the angle is easier from the top but what you have to remove to get at the KS does not make this feasible.
Basin wrenches are fairly inexpensive so it's worth giving it a shot. But if you have access to a welder and the KS is most likely toast anyway, why not just hit it with a Few welds? The easiest way to get these out is to just use the socket on the KS lid. Just try to tighten it in a little first and then try to back it out. Once it breaks free, it should come out pretty easily as they are a NPT thread and have a slight taper to them.
If the KS already has what appears to be sealant or what may look like a thread locker (reddish color), this is all the sealant you need. No need to add more and I've just reinstalled them a few times with the existing sealant and they haven't leaked yet. So I wouldn't consider adding any additional sealant to the threads. All the new KS's I've seen already have something applied to them. Take a close look at your new KS to confirm this.
Thanks 4Door. It is going to have to be a welder indeed. I sit here humbly typing this having failed yet again another night. Tried the Basin Wrench (was not large enough to bite on it), Vice Grips a no go. Welding is definitely the route to go. So did you just tack weld it on the very outer edges like on three sides then?
The good news is I got the starter off but now am wondering if I should replace it since it has not been replaced in the 12 years I have owned the car. If so what is a good brand to go with?
I have a new Hobart wire welder that I have not put to use yet, need to get an argon tank and also had a pacemaker put in and I need to be careful welding. Been using my Lincoln Ranger 8 Stick so I guess this will give me a good reason to purchase a tank and get the MIG set up. Would be much easier and cleaner to hit with the wire welder I am sure than stick right? Or do you think I could hit it okay with the stick? I am just thinking slag wise.
Did you actually use a torque wrench or will I be safe just getting them snug? 14' lbs is not much. I would have to get a torque wrench since I don't currently have one.
I poked a small screw driver in the hole as suggested and it broke through all the gunk and a ton of coolant came out. Will feel great to get it all out and this all put back together. Thanks again for all the help!
. So did you just tack weld it on the very outer edges like on three sides then?
The good news is I got the starter off but now am wondering if I should replace it since it has not been replaced in the 12 years I have owned the car. If so what is a good brand to go with?
Would be much easier and cleaner to hit with the wire welder I am sure than stick right? Or do you think I could hit it okay with the stick? I am just thinking slag wise.
Did you actually use a torque wrench or will I be safe just getting them snug? 14' lbs is not much. I would have to get a torque wrench since I don't currently have one.
I poked a small screw driver in the hole as suggested and it broke through all the gunk and a ton of coolant came out. Will feel great to get it all out and this all put back together. Thanks again for all the help!
Been fortunate that mine have always come out with just using the socket, so never had to weld them before. But seems like to me whatever you can reach up in there with would be your best option. IIRC And you look at your new KS you will see how the top/lid is placed into the KS body, then the edges of the KS body are bent over the lid and believe there are then just 3 or 4 tack welds at the seam. Don't think it really matters how pretty is as long as it holds well enough to wrench it out of there.
I did use a small 1/4" torque wrench that is in inch pounds to get these in. You could probably "ball park" it by hand if you have experience doing this. But really why, when you could pickup a torque wrench fairly cheaply at a place like harbor freight. Sure it may not be as accurate as a snap-on, but they work pretty well and seem ok for the average wrencher.
On the starter....why bother if it's working fine now? Sure it's old, but if it ever does fail replace it then and its (to me) such an easy replace anyway. Not to mention the replacemnt stuff isn't as good sometimes as the original. If you do replace, seriously consider getting the Corvette Starter for the LT1 which is a direct Bolton.
Awesome! Some great tips. Thanks again. I typically always try to be preventative and would have replaced the starter but it seems like you said the replacement stuff is not as good as the original and it will always come back to bite me. Thanks for the help. Getting a bottle for my welder tomorrow after work so hopefully will have it knocked out. I will get me a cheap torque wrench at HF Tools. Thanks once again for all your help. Hopefully I won't have to bother you anymore. Much appreciated!!
don't replace starter if good. just clean it up and tighten the connections on it.
I replaced my starter because it was not cranking when around zero deg F. after 6 months I brought it back it was so loud cranking got louder and louder lifetime warranty new . got all my money back original in it now works good above zero F.
the forums are here to help owners make repairs . also save money and time trying to find out whats going on...
Well got the KS out. It was not fun. LOL.. After welding it I got the wrench on it and the whole head of the KS popped off. Only thing left was the threads in the block sticking out. So took 1/2" extension and welded it up on the stud left in the block and finally got it backed out. Whew! I was sweating it.
Got everything buttoned up. Filled the engine block with 50/50 own mix of antifreeze till it was up to the top of the water pump housing where the thermostat sits. Put new hoses and thermostat in and then filled the overflow tank. Started her up everything seems great.
Only issue now is my low coolant light will not go off? I drove it for about an hour and the temperature is staying right in range. Checked the tank both hot and cold and it is where it should be do you think my sensor is bad? When they go bad will they stay on? I disconnected the battery again thinking maybe it will reset something but it never did. I can unplug the sensor plug and the light will go off. Am I missing something? Maybe pressure built up or something? I even loosened the brass screw on the thermostat housing to see if that would make a difference and just antifreeze starting coming out.
Do you think I am okay and its just the sensor or any other suggestions possibly? Cleaned up the old starter like suggested and it is working fine. Thanks again for all the help and information. Let me know what you think about my low coolant light. Thanks
Most likely the sensor in the reservoir is stuck somehow. Did you not flush and clean the reservoir while the system was drained? The reservoir gets a lot of junk in it and this can cause the sensor to stick and not make contact.
If you're sure the system is bled properly and at the correct level, then there is not much else you can do. You can try to tap on the tank near the sensor location to see if that frees up the sensor. If not, it may later decide to start working after driving it for a bit like mine did recently. If nothing else works then youre only other option is to replace the reservoir since the sensor itself is not replaceable.
Yeah, I flushed and cleaned out the reservoir really well. I wonder if maybe when flushing it something got stuck in there that did not work loose and just happened to catch right on the sensor then? That is crazy, they don't sell just the sensor at all? How sad. Hopefully Rock Auto carries replacement reservoirs then at a decent price. I will give her a tap and see what happens and then drive it some more to see if it works loose and go from there. I guess just unplug it until I get a new one. I hate idiot lights but it is good to have if you need it letting you know of a possible coolant leak. Thanks 4Door, appreciate it as always!
I just checked on RA and they show one for our cars. The plug looks different though. This one looks much larger and the plug looks to be on the side instead of the bottom? So you think this is an error?
Something is not correct with that picture of the sensor in your link. That looks more like a sensor that goes into the radiator side tank. I recently replaced one that looks just like it on my 92 Buick Regal witha 3.8L engine.
On our cars (94-96 L99/LT1) the sensor is molded into the reservoir and is not something that can be replaced. If the sensor dos not free itself up, then your only options are to remove, flush the tank and see what happens. If that does not work, then the only other option is to replace the entire reservoir.
Yeah, I agree. I did not think it looked correct and went home after work last night and verified. That is completely different. Good to know. Thanks again.
FYI - make sure you install the knock sensors to the correct torque. 14 ft. lb's is all they need. Too much and you'll start loading up the PCM with knock.
4DoorSS, I unplugged the sensor on the low coolant and drove it. Two weeks later plugged it back in and its working fine now. Issue now is that even with new radiator and I believe 195 thermostat the car is about at 1/4 temp on the thermostat. I like the car running cooler but the heat will barely get warm enough in 40 weather (not good for the wife). I back flushed everything, heater core etc.
Question is, am I safe in the winter time putting some card board around behind/in front of the radiator etc to help it warm up quicker/better. If so how much and where is the best location to place it... in front or behind, around the edges? Pretty sad to be asking this on a November day with it being 69 degrees outside I know.
Any other recommendations and tips would be truly helpful. Anything else I may be missing? Do I need to replace the heater core again? I put in a new one not too long ago maybe 5 years ago. Thanks, need to keep the wife warm so I can keep my caprice Happy Wife, Happy Life...I guess. LOL
You could do that with the cardboard but don't think that will help your no heat issue. I believe when that is done it's primarily to get the rad up to temp faster by blocking air flow. Ok to do this I guess as long as you don't let the car overheat by blocking too much airflow. But this will not help with getting heat into the car.
I strongly suspect the heater core is blocked again preventing hot coolant from flowing through the entire heater core. If this was flushed before but the rest of the cooling system was not.....then it most likely got blocked again. Maybe the flushing you did before did not get all the junk out of there. I believe heat output could be affected if you don't have hot coolant flowing through the ENTIRE heater core.
Awesome, thanks 4Door. Appreciate the help as always. Going to get to flushing again. Sucks wish I would have just replaced the heater core when I had everything drained to play it safe. I know its a pain but at least I would have had peace of mind especially after all the knock sensor troubles I had. LOL. Reason I didn't was because it seemed to flow really well when I put a hose on it.
So on the seats for Bonny and for Roadmaster just look for 94-96 then and hope I get lucky? Do all the same years fit I am guessing or are there more than just 94-96. Would the Leather Buick Park Avenue Seats fit too if I get desperate. Looking for the Gray Leather. I know the hardest to find but what seats will fit? Is there a list on here that someone has compiled? Thanks so much!
FWIW I have used a 1 gal empty water jug and a funnel placed under the car and did pull "slightly" the lower heater hose from WP and collected the coolant. To the point I didn't spill a drop. If your coolant is still clean and no crap in it you can re-use. I have even used one of those paper paint strainers in the funnel on re-fill to get any small specs from going back in
While you will spill some coolant, if you pull the heater line at firewall just use a bolt or other form of "plug" in the end to keep coolant from coming out of the hose once disconnected. The heater core itself will also leak coolant out once you pull the hose off.
if heater core is flowing easily with flush/back flush that indicates it is clear
While its been several years since I lived in Wisconsin...I did have cardboard in front of my truck radiator for the winter. My Dad did the same thing to his car when I grew up in upstate NY. Just left it on the car for months. Temp gauge never got up above 'normal" and heater worked.
Having to do the opti work on my 96 impala I had to drain the coolant and since it was 3..5 yrs since I did the coolant ... I drained the block/complete coolant system just this past week.
so on the refiling of the coolant even if the block is not fully drained you must use the goose neck T stat bleed screw valve to remove all the air . if any air in system heat will be weak. I fill the system where the T stat sits until full . then fill the plastic pressure tank. then start engine and watch the temp gauge. when it gets to the normal reading then you bleed the system at the T stat goose neck valve. then drive it around and see how hot it gets .. then re- bleed again until solid coolant comes out .. do not open too much and use some material to catch any drippings or you may have to get a new opti ..
yesterday when I put it all back and drove it the heat was hot but not really hot like burning hot as it usually is. sure enough got some air out at the bleeder . then the heater was real hot . this is common even in the GM trucks using the 5.3L engines. in those you run the engine until normal temp with the pressure cap OFF, and rev it several times .
Well I have been driving the car for two weeks now with no leaks at all. Just started to notice some coolant leaking on the drivers side about where the knock sensor is. I jacked it up tonight thinking maybe i did not have it torqued enough. The coolant appears to be coming from up above by the rear of the exhaust manifold drivers side.
I started the car up while jacked up and on the drivers side very front exhaust manifold bolt I can see a little coolant bubbling from around the front exhaust port on the top side. I am guessing it is coolant. After about 5 minutes it stopped.
While under the car when running I can see more coolant starting to form a larger drop back by the rear exhaust manifold bolt drivers side. I am wondering if when the radiator went out and the coolant light came on I drove it about 4 miles to make it home. Do you think I cracked the head or warped it from getting too hot? Would that cause it to start leaking? It definitely is from higher up around the exhaust manifold. I sure hope I didn't crack or warp anything but it is definitely leaking somewhere.
looks like you blew a head gasket hopefully and not other costly damage.
cast iron heads can take the heat , too much heat they can crack ..
aluminum head if it was on your LT1 with what you did driving with the radiator blown would require new heads.
I would try some stop leak first see if it works. use bars stop leak only 1/4 of the product and pre mix before install. remove T stat and install in the water pump t stat hole . see it the coolant pressure holds after a few days .
now you know why you have little heat air in system .
J Cat, when you say pre mix before install should I just use water or antifreeze to mix it? Or I am guessing just the 50/50 mix I have already? Sorry, I guess that may be a stupid question...
Based just on your description, an alternate to blown gasket just might be a grommet letting go on the crossover banjo bolt. I skimmed but did not see anything about terrible overheating jump off the page.
I would not be leaning toward a head gasket/head issue at the moment...pretty uncommon on the LT1 with iron heads. I would however be leaning more to the banjo bolts for the crossover tube or the crossover tube itself. Rust, years, overheating and neglected systems take their toll on these metal tubes and banjo bolts/seals. There is also a coolant line going to and running under the throttle body and down the passenger side of the intake. Not too many places to lose coolant from on these engines. Once a leak starts, the coolant can drip or can move while driving making the leak appear like it's coming from other areas so it NEEDS to be pinpointed.
But the uncertainty of the leak can lead to a lot of speculation in threads like this where it's difficult for us to see what you NEED TO inspect yourself. So take a closer look at the areas that the coolant can pass through. Maybe use some dye in the system to vpbetter determine a leak point. If all else fails or your just not comfortable with finding the cause of the leak yourself, just take the car to a shop or 2 and ask them to evaluate/find the issue for you. Most shops won't charge to do this or may just charge a small fee to do it.
Once the issue is discovered, you can then figure out the best way to get it fixed. You may decide to just let them fix it, or you could reach out to us again with some definitive findings and we could then give you some ideas of how to handle the repair yourself.
Edit - forgot to mention. When doing the throttle body bypass mod, the metal line running on the passenger side of the manifold was rusted pretty bad. The barb on the end of the line where the rubber hose installs was in bad shape. A lot of the metal had rotted in this area and I just cut off about an inch or 2 of it and slid the hose on further with 2 clamps. So it is possible the tube itself is starting to rot.
Too much of a PITA to have to replace the entire metal line going to the back of the heads. If I ever have to replace this line, it will be replaced with AN fittings and hose....a few threads with info on this. One thing for certain, if I ever pull the engine, I WILL replace the stock 20 yo plus line while the motor is out.
Yeah, I was really stupid. Usually always watch my gauges, but by the time the car dinged (idiot lights) I had already went apporximately 4 miles and that was in the Oklahoma heat. So it did not take much for it to ramp up fast and then I had shut her down. I have 270k+ miles on the baby LT1 4.3 original motor and tranny but wanted to try and get 300k and push it just curious to see what I could get out of her. Bought the car with 79k on it and drove it for 12 years. So got my moneys worth.
I was planning on a motor swap once this one went out but wanted to make this last as long as possible. Really want to put an LS1 or 2 in it.
When I had it jacked up last night I could see from underneath the coolant collecting on the drivers side year exhaust manifold bolt and going down onto the oil filter (lowest point) eventually. I bet it is a head gasket. I know it could be coming from elsewhere but I have a feeling that is it under the circumstances. I will check the crossover tube though. Its odd that I drove it for two weeks and no leaks like this. Had some tranny fluid slowly leaking out of the radiator connection and put some blue thread lock on it and it fixed it.
Never replaced a head gasket before. Are they hard or even worth doing at this point? I have the money to get an LS motor for it.
Should I try the barsleak and drive her till she drops? No over heating, no power loss (of course its a 4.3 not a hot rod anyway) LOL.
I really need to focus on the 66 SS convertible restore but have been putting it off for over 16 years now anyway. LOL Would like to keep this one and would be faster to get this one back and running and hot rodded up than the 66. Are the LS swaps hard if you get the motor/tranny and PCM all at once? Is that the best way? Is there any postings or info on an LS Swap on our Forum? I will have to look.
Thanks for the tips again. After all the knock sensor trouble I have this Yeah!
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