: BARS Head Gasket Fix and Aux Fan control



gdmarques
06-09-08, 10:37 PM
I've seen several posts emphatically stating that no "fix in a bottle" product will repair a leaking head gasket on a N*. I recently used the relatively new BARS product for repairing head gasket leaks in my 1998 Deville with 150000 miles and I can tell you that it worked AMAZINGLY. I had coolant leaking into the leftmost cylinder at the firewall side of the engine, and fouling the plug. Had antifreeze in the oil, rough idle, etc...

I followed the instructions on the bottle with the addition of removing that spark plug and pulling the injector connector so I wouldn't be spraying fuel into the cylinder. Ran the engine for 15 minutes as instructed (fairly loud with the open cylinder and tons of white smoke!) After allowing the engine to cool I reinstalled the plug and connector to the injector and started the car. IT RAN PERFECTLY. I have been running it for about three weeks now through a range of temperatures and fairly hard driving to see if it will fail. No problems so far.

Now for the second part. My AC compressor is shot. Since the sensor switches the car to economy mode it runds warmer than I would prefer, particulalry with the head gasket "repair". I installed an adjustable thermostatic switch this weekend, tapping into the green wire on the #1 relay. This runs BOTH fans, switching on at low speed I beleive at about 185 degrees. The problem is that I immediately get a code 1660 (error in the fan circuit) and a check engine light. Anybody have a suggestion as to how to wire this in such a way as to avoid the error code?

dkozloski
06-09-08, 11:09 PM
please keep us advised on the Bar's Leak. Nobody has been able to make the repair in a bottle deal last more than a little while.

lusterblade
06-10-08, 12:53 AM
I used the Bar's Leak Headgasket repair. I believe it lasted about 2 weeks tops.

tateos
06-10-08, 03:03 PM
I think the reason most everyone says the head gasket leaks cannot be fixed with a bottle is because usually it is exhaust gas that leaks from the combustion chamber into the cooling system, not the other way around. Another reason is that, frequently, the cylinder head bolts have let go from the block and so provide no clamping force; there is nothing that holds the head gasket tightly between the block and the cylinder head.

I have had 2 '97 N*s fail this way, but please correct me if I'm wrong, guys.

Submariner409
06-10-08, 03:22 PM
BINGO !!! :thumbsup:

Even in a cast iron head/block setup, if a head lifts and loses clamping pressure on the gasket, as opposed to the gasket blowing out completely, there's very little you can do to salvage the gasket integrity. One reason for going to the immense clamping pressures allowed by a good head stud installation. I would imagine that the Northstar block, with its open aluminum deck and cast-in liners, would distort like crazy under torque loads from only 10 bolts per side. If there were 5 or 6 bolts per cylinder (quite an engineering job), the head lifting problem wouldn't exist.

Ranger
06-10-08, 09:40 PM
FWIW, My money says the fix is temporary at best. In all honesty, there is only one way to repair a leaking head gasket, and it is not cheap, easy or in a bottle, but please do keep us updated.

gdmarques
06-12-08, 11:04 PM
While I absolutely agree with everything you all have said (and I have replaced my fair share of head gaskets over the years on other cars) all I can say is it appears to be working well so far. If this was my only car and I had to depend on it everyday for transportation I wouldn't depend on this fix, but as an occasional local driver $29 is a heck of alot cheaper than a head gasket. I could dump a bottle in every month for the next 5 years and probably still come out ahead. I've also gotten 150,000 miles out of this thing, so it doesn't really owe me anything.

And when the thing finally lets go it should make for a heck of a show!

Necrosan
06-14-08, 03:19 PM
I ran this stuff through a 2002 Impala, lasted roughly 2 months. The leak wasn't even bad in the Impala. Good luck with it.

Destroyer
06-14-08, 09:53 PM
Problem with this stuff is that everyone with an H/G issue will use this stuff, sell the car like nothing is wrong and then the new owner is SCREWED!. Its already happened many times I'm sure.

chubbyranger
06-15-08, 08:54 AM
Problem with this stuff is that everyone with an H/G issue will use this stuff, sell the car like nothing is wrong and then the new owner is SCREWED!. Its already happened many times I'm sure.

:yeah: http://www.cadillacforums.com/forums/northstar-performance-technical-discussion/142026-need-diagnosis-98-sts-overheating.html

gdmarques
06-17-08, 09:11 PM
Can aybody respond to the SECOND part of my post regarding the cooling fans?

Submariner409
06-17-08, 09:58 PM
Easy: Return the fan(s) to normal PCM/sensor/A/C control. As designed.

gdmarques
06-18-08, 08:36 AM
Now for the second part. My AC compressor is shot. Since the sensor switches the car to economy mode it runds warmer than I would prefer, particulalry with the head gasket "repair". I installed an adjustable thermostatic switch this weekend, tapping into the green wire on the #1 relay. This runs BOTH fans, switching on at low speed I beleive at about 185 degrees. The problem is that I immediately get a code 1660 (error in the fan circuit) and a check engine light. Anybody have a suggestion as to how to wire this in such a way as to avoid the error code?

See the part about my AC compressor. If I don't use the aux fan switch the car pukes its coolant if it idles at a standstill for a few minutes because the car senses low Freon and disables the compressor circuit. I assume the Engine temp sensor is malfunctioning causing the engine cooling fan not to switch on in spite of the AC problem, although the temp readout on the DIC seems to be accurate. Since jumping the green wire is causing both fans to run I think the relays are working just fine. I could spend a few hundred bucks to repair the AC, which eventually I will probably do, but in the meantime I have heard of many people installing these fan switches but seen no mention of the error code.

Ranger
06-18-08, 11:55 AM
If I don't use the aux fan switch the car pukes its coolant if it idles at a standstill for a few minutes
I hate to say this, but I go back to my original statement. I think this proves that the "repair in a bottle" is not working.

chubbyranger
06-19-08, 04:21 AM
If I don't use the aux fan switch the car pukes its coolant if it idles at a standstill for a few minutes because the car senses low Freon and disables the compressor circuit. I assume the Engine temp sensor is malfunctioning causing the engine cooling fan not to switch on in spite of the AC problem, although the temp readout on the DIC seems to be accurate.

The engine temp sensor should be independent of the AC system function - if the car gets too hot it turns the fans on. It should be calibrated such that the fans have sufficient time and capacity to reduce the coolant temp so to not cause coolant loss. So there should be no correlation between the AC not working and the overheating problem. That leads me to one of two conclusions: a) as Ranger said the HG fix in a bottle isn't cutting it and/or b) the temp sensor is not working correctly and causing both the overheating and the code.

gdmarques
07-08-08, 11:21 AM
I beleive the engine temp sensor is either not sending the proper signal to start the fan, or the engine computer is not sending the signal. The relays are fine as the external temp control I installed uses the relays to start both fans at the temp I set.

Regarding the Bars HGR, it is still working fine. I had fouling of the number one plug with coolant as well as oil in the coolant and vice bersa. All three problems are still resolved after about 2 months.

I did not change the engine temp sensor for the simple reason that I couldn't locate it on the car and heard it was a difficult task. Can anyone help me with info on this?

Submariner409
07-08-08, 11:31 AM
The coolant temperature sensor is in the coolant crossover, just to the right of and below the throttlebody. A hex head pipe plug with an electrical connector sticking out the back. www.rockauto.com (http://www.rockauto.com) , $7 - 8 ?