Overheating after WP replacement... Place your bets...
10-13-2010, 05:13 PM
#76
Former Sponsor
But greg, the sender isnt much more than a few inches of water away from the heads. sure, it will boil first, but its hard to keep that hot water away from the sensor. it lags, but not that much. without the water pump moving, that temp rises very quickly before overheating, even though, your right, the heads are hotter. want a test. take a cookie pan and fill it with water. put 1/4 of it over the flaming stove. when it starts to boil, the entire pan will be boiling, even if the water is 8" away. convection with water works fast!
10-13-2010, 05:14 PM
#77
Former Sponsor
10-13-2010, 11:29 PM
#78
Burning Brakes
Thread Starter
you guys are smokin crack. you cant even get close to the upper area of the temp gauge with the cap off. why, because you get localized expansion and heating of the water, and the water will rise and boil over LONG before it overheats or gets a meaningful temp value.
But I'll add the following: As car warmed up towards second white line (note that temperature sensor sending temp to dash is working just fine), the reservoir began filling...
While that was happening, there was no heat coming from heater on high.
And again... Fans never came on.
End result - Cut the engine between white and red, and lost a gallon of coolant boiling out of the reservoir.
Enough of that!
Being that my waterpump is an "OBehave"... I'm leaning towards following his advice at this point (loyalty).
Reading through the "voodoo magic" above...
You guys are the best. I really do feel like you all are providing excellent advice... Just have to get my next steps figured.
Anyone want to take a shot at what it means that I didn't get any heat from the heater? I just replaced the heater valve (was getting heat while AC was on before the waterpump replacement)...
I'm thinking it's time to simply move to the jack-stands and confirm whether or not the marks have shifted on the water pump (as Ed described in his earlier post)...
10-13-2010, 11:38 PM
#79
Rennlist Member
I've got a $1 on air bubble...
10-14-2010, 01:42 AM
#80
Burning Brakes
i'm betting the impeller fell off the shaft mine did that after a rebuild i had it tack welded back on with a small dose of tig works awsome now took me a few overheats to figure it out though sounds exactly like your deal good luck
Paul
Paul
10-14-2010, 08:38 AM
#81
Burning Brakes
Thread Starter
Ed and I would both be very disappointed with this being the reason.
10-14-2010, 08:43 AM
#82
Captain Obvious
Super User
Super User
cant wait to hear what the issue is! certainly try and burp the system as I have suggested. Its pretty fool proof. then, as Obehave has suggested, remove the t-stat and see if it works, also , install it wedged open if you really want to diagnose water pump or radiator issues. Its the only way I know to really narrow it down, and its an easy test. if you dont got flow, you got a radiator or pump issue. short circuit the radiator and still dont have flow, its the pump. (or a rag, which is not that uncommon)
10-14-2010, 08:56 AM
#83
Take out your temp II sensor, take a funnel and fill it up, and start the car. if you have fluid coming out fast there while running, you know your pump is working. My bet is on air.
Quick and easy.
Quick and easy.
10-14-2010, 10:58 AM
#84
Rennlist Member
Join Date: Oct 2005
Location: Gatineau, Québec, Canada
Posts: 5,178
Received 1,318 Likes
on
499 Posts
"Anyone want to take a shot at what it means that I didn't get any heat from the heater? I just replaced the heater valve (was getting heat while AC was on before the waterpump replacement)..."
Simple, if there is no circulation of coolant, no warm coolant will bring heat to the heater. No circulation, no heat.
If I were you I would folow Ed's advice and check the paint mark on the pump first.
That way, you will know for sure if the pump is turning or not.
Good luck.
Simple, if there is no circulation of coolant, no warm coolant will bring heat to the heater. No circulation, no heat.
If I were you I would folow Ed's advice and check the paint mark on the pump first.
That way, you will know for sure if the pump is turning or not.
Good luck.
I think a Bookie could make a lot of money here .
10-14-2010, 12:58 PM
#86
Rennlist Member
Thanks! yes, its not like i havent been there before. in fact, that cap cant be off for more than a few mins or you willl get a boil over condition. (or an expansion condition and you saw that)
Now, the issue. because you started to see expansion, but no heat, in the heater core, tells me there is no circulation. I cant do that test, as I dont have a heater core.
. anyway, I like the idea of pulling the temp II sensor, to see if water spouts out, but im not convinced that it is in the right spot, but that could because I dont know if it is in the right spot.
anyway, your pump seems to be bad. Its NOT air in the system, if you bled it like I suggested. (cap off , squeez lines until you fee no air in the system. This works 100% of the time.) the other thing you could do, if there is a chance that a stuck t-stat could is inhibit flow to the heater core, which is certainly not the case. (because in cold weather, the heater works great, and the radiaor is shut off by the tstat ). so, sorry, it looks like the water pump is the problem.
I dont think anyone really respects the force on the shaft of the impeller to hold the impeller in position. If there is any issue with the press fit or a bad weld if that what was done to secure it, it will spin off. Ive seen it several times.
Now, the issue. because you started to see expansion, but no heat, in the heater core, tells me there is no circulation. I cant do that test, as I dont have a heater core.
. anyway, I like the idea of pulling the temp II sensor, to see if water spouts out, but im not convinced that it is in the right spot, but that could because I dont know if it is in the right spot. anyway, your pump seems to be bad. Its NOT air in the system, if you bled it like I suggested. (cap off , squeez lines until you fee no air in the system. This works 100% of the time.) the other thing you could do, if there is a chance that a stuck t-stat could is inhibit flow to the heater core, which is certainly not the case. (because in cold weather, the heater works great, and the radiaor is shut off by the tstat ). so, sorry, it looks like the water pump is the problem.
I dont think anyone really respects the force on the shaft of the impeller to hold the impeller in position. If there is any issue with the press fit or a bad weld if that what was done to secure it, it will spin off. Ive seen it several times.
Mark, I have to agree with you here. I followed instructions on "open system bleed out" and noted exactly what you mentioned.
But I'll add the following: As car warmed up towards second white line (note that temperature sensor sending temp to dash is working just fine), the reservoir began filling...
While that was happening, there was no heat coming from heater on high.
And again... Fans never came on.
End result - Cut the engine between white and red, and lost a gallon of coolant boiling out of the reservoir.
Enough of that!
Being that my waterpump is an "OBehave"... I'm leaning towards following his advice at this point (loyalty).
Reading through the "voodoo magic" above...
You guys are the best. I really do feel like you all are providing excellent advice... Just have to get my next steps figured.
Anyone want to take a shot at what it means that I didn't get any heat from the heater? I just replaced the heater valve (was getting heat while AC was on before the waterpump replacement)...
I'm thinking it's time to simply move to the jack-stands and confirm whether or not the marks have shifted on the water pump (as Ed described in his earlier post)...
But I'll add the following: As car warmed up towards second white line (note that temperature sensor sending temp to dash is working just fine), the reservoir began filling...
While that was happening, there was no heat coming from heater on high.
And again... Fans never came on.
End result - Cut the engine between white and red, and lost a gallon of coolant boiling out of the reservoir.
Enough of that!
Being that my waterpump is an "OBehave"... I'm leaning towards following his advice at this point (loyalty).
Reading through the "voodoo magic" above...
You guys are the best. I really do feel like you all are providing excellent advice... Just have to get my next steps figured.
Anyone want to take a shot at what it means that I didn't get any heat from the heater? I just replaced the heater valve (was getting heat while AC was on before the waterpump replacement)...
I'm thinking it's time to simply move to the jack-stands and confirm whether or not the marks have shifted on the water pump (as Ed described in his earlier post)...
10-14-2010, 01:04 PM
#87
Rennlist Member
It absolutely has to go BACK IN! otherwise you dont get a flow pattern. its opening up a passage and closing off another at the same time.
you wedge it open by putting a circular wedge with a hole in it. (a toy motor brass gear works great). its only 1/4 thick and doesnt matter how large the hole is, as it slips over the t-stat front guide shaft, and then back into its normal position. this forces the t-stat open, and pushes the rear spriing loaded surface to the rear of the t-stat housing to seal it up, like the engine was warm. it is a perminant fix if your t-stat was bad (very rare). But , it will take twice as long to warm the car up under normal conditinos. during race conditions, on the track warm up happens so fast, its not an issue, but personally, I like it to work normally to warm the car up quicker, for less warm up wear and tear.
mk
you wedge it open by putting a circular wedge with a hole in it. (a toy motor brass gear works great). its only 1/4 thick and doesnt matter how large the hole is, as it slips over the t-stat front guide shaft, and then back into its normal position. this forces the t-stat open, and pushes the rear spriing loaded surface to the rear of the t-stat housing to seal it up, like the engine was warm. it is a perminant fix if your t-stat was bad (very rare). But , it will take twice as long to warm the car up under normal conditinos. during race conditions, on the track warm up happens so fast, its not an issue, but personally, I like it to work normally to warm the car up quicker, for less warm up wear and tear.
mk
10-14-2010, 08:08 PM
#88
Burning Brakes
Thread Starter
Can you take a picture of Sensor II and post it? Want to make sure I'm on the right one... I'm all about trying to diagnose the pump from outside...
10-14-2010, 09:55 PM
#89
Captain Obvious
Super User
Super User
It absolutely has to go BACK IN! otherwise you dont get a flow pattern. its opening up a passage and closing off another at the same time.
you wedge it open by putting a circular wedge with a hole in it. (a toy motor brass gear works great). its only 1/4 thick and doesnt matter how large the hole is, as it slips over the t-stat front guide shaft, and then back into its normal position. this forces the t-stat open, and pushes the rear spriing loaded surface to the rear of the t-stat housing to seal it up, like the engine was warm. it is a perminant fix if your t-stat was bad (very rare). But , it will take twice as long to warm the car up under normal conditinos. during race conditions, on the track warm up happens so fast, its not an issue, but personally, I like it to work normally to warm the car up quicker, for less warm up wear and tear.
mk
you wedge it open by putting a circular wedge with a hole in it. (a toy motor brass gear works great). its only 1/4 thick and doesnt matter how large the hole is, as it slips over the t-stat front guide shaft, and then back into its normal position. this forces the t-stat open, and pushes the rear spriing loaded surface to the rear of the t-stat housing to seal it up, like the engine was warm. it is a perminant fix if your t-stat was bad (very rare). But , it will take twice as long to warm the car up under normal conditinos. during race conditions, on the track warm up happens so fast, its not an issue, but personally, I like it to work normally to warm the car up quicker, for less warm up wear and tear.
mk
My borther's S4 started to slowly overheat about a month ago, so I pulled the T stat in a parking lot, just to get him home but that didn't make any difference and it started over heating even faster.....so we got Rod's trailer and pulled it home. I was suspecting the waterpump impeller and was going to leave it as a winter project to work on But if the T-stat has to be in, I'll throw a spare one in and go for a quick spin. Might get lucky and could only be a bad T-stat.
10-15-2010, 03:05 AM
#90
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Ever wonder why Porsche mounted the coolant tank HIGHER than the engine and radiator ???? that way the could run bleed lines from the highest point of the engine and top of the radiator to remove any air bubbles. The 944 was not set up this way and you HAD to bleed out from the thermostat housing. Sorry but air bubbles just do not exist in the 928 cooling system. That is an urban myth.... Now as to why is this car overheating ??? could be the impellor was not pressed on far enough and it is trapped against the block , it happens ! Removing the upper radiator hose and starting it will tell the story albeit somewhat messy