Head Gasket First Aid

[turbocruiser]

Hi all, the subject sorta says it all but basically I was wondering what steps we all say someone should take to minimize the damage due to drastic temp spikes. Since overheating seems so statistically likely with the 80 headgasket, I think it would help to know "basic first aid" and to know what to do if you are sitting at stoplight and the temp gauge starts spiking. This may, or may not, make the difference between a headgasket repair and a head AND headgasket repair. In other words these basic first aid measures may make the difference between a warped or a cracked head, and just a junked up headgasket??? Who knows, anyway, I put together a short list and was hoping others would add or take out various steps and explain why. Who knows, it may make a difference? So in this order do these things if the temp starts spiking: Ohh yea, do them all rapidly!
1. Shut off AC. Even though the switch supposedly stops the AC from engaging when temps are above 220 IIRC?
2. Slide climate control switch to full hot, put fan on full high (make sure setting for defrost is NOT selected as AC may be activated?), turn on rear heater to full high.
3. Pull over and pull off the road and run engine with all heaters on for a few seconds. Do not know how long to try this, maybe thirty seconds, maybe less if the temp keeps spiking, maybe more if it drops? Any thoughts? What's the difference between helpful and harmful "CPR" in this case?
4. Shut engine down.
5. If radiator overflow tank is empty, add water to it right away, while never opening radiator itself.

What NOT to do ( again please add to or take off and explain why ) :
1. Drive across town trying to get to the shop while the temp keeps spiking.
2. Leave AC on. Even though the switch supposedly stops the AC from engaging when temps are above 220 IIRC?
3. Open radiator cap.
4. Squirt things down with cold water?


Okay, so what would you all say? Thanks, you people Rock!

 

[IdahoDoug]

Pull off where it's safe.
Heaters on high, all power drains off except heater fan and 4 way flashers.
Leave engine running at an elevated idle (1200rpm ish) and watch gauge to ensure it's not going to rise.
Open hood and check for coolant in overflow or other signs of distress (belt off, blown hose, etc).
When temp stabilizes, drive slowly to wherever you're going to have it serviced.

The objective here is to prevent a peak temperature spike as that is what will maximize the thermal expansion/contractions/pressure that are hardest on the HG. Shutting it down (unless it appears to be getting hot even at a high idle) will cause localized hot spots and a heat spike as residual heat energy in the block soaks into the no longer circulating coolant.

DougM

 

[turbocruiser]

Okay, great answer, Doug, thanks. It makes sense that if the temp slowly lowers with the heaters running full and with the motor running at high idle ( I assume high idle is to induce more airflow with fan and also to induce more cycles of thermostat?) then this is the "first aid treatment" to use. But, what if the temp hovers around the red temp line, not necessarily hitting it, but hovering around it? I personally would not want to add any more load to the engine by trying to take it to a shop. On the other hand the hotspots would be worrisome but what else would help if the temps wont lower with all the other treatments so to speak? I wonder whether turning the engine off, waiting for a few short minutes, turning it on again, etc would gradually at least minimize the hot spot problem? Or, would it just add to the problem? Another question about adding to or taking away from the problem is this...would it ever, for any reason at all ever, be recommended to remove the radiator cap??? I'm talking about wrapping hand with shirt, springing the cap loose and springing away from the spray at the same time? I'm not talking personal safety here, I'm talking motor protection so if one is willing to take the risk, would removing the radiator cap ever help in any way at all ever? Again, thanks for the answer, that was perfect. I'm not trying to tire this out, I'm just trying to figure it out, so thanks for the help here. For All!

 

[PHAEDRUS]

one quick issue here is to make sure that you have enogh coolant.
before you start on steps 3 and 4 as prescribed you would need to make sure that your coolant level is in line. if not the added loss of coolant can cause the temp gauge to rise even more.
as doug notes flat idle will not help you much try to maintain 1000 to 1400 rpms and make sure the fan viscous coupler is engaging. how you ask? open the hood and it will be apparent.
As far as removing the radiator cap I have a really nice scar on my left hand from doing just that. apparently was a little low on coolant with a bad rad cap and it vapor locked in the rad. I opened it and gave myself some nice third degree burns on my hand.
not fun, also my dog was upset when I used her water dish to dunk my hand in till I could get home.
Dave

 

[turbocruiser]

[quote author=Phaedrus link=board=2;threadid=17673;start=msg171084#msg171084 date=1086675426]
one quick issue here is to make sure that you have enogh coolant. before you start on steps 3 and 4 as prescribed you would need to make sure that your coolant level is in line. if not the added loss of coolant can cause the temp gauge to rise even more. as doug notes flat idle will not help you much try to maintain 1000 to 1400 rpms and make sure the fan viscous coupler is engaging. Dave
[/quote]

Thanks Dave, that makes sense, so prior to step 4 of shutting the engine off, we should insert something like:
4. Make sure coolant level in coolant overflow tank is full.
5. Make sure no belt is popped or loose.
6. Make sure fan and fan clutch are working well.

So if any of the treatments so far work, then, clearly, continue to lower the temp safely with high idle, heaters on high, etc and then drive or tow to the top shop in your area. If however they still do not work, in other words plenty of coolant, good belts, good fan, good fan clutch, what would you want to do? Would the start and stop of the engine every two minutes for about thirty seconds or so help to solve the hotspot problem or at this point is it just a matter of shutting her down and hoping for the best thing being just a HG r&r? Thanks again, this is totally helpful. Cool.

For All!

 

[IdahoDoug]

If the temp is hovering at/near the redline and is not abating then you'll have no choice but to shut it down. In that case, open the hood to allow for maximum radiant heat loss and increased air circulation for a stopped engine.

Under no circumstances should you remove the radiator cap to assist cooling a hot engine. Aside from the physical dangers noted, this is the opposite of what is needed to forward your goal of cooling the block and here's why. The coolant of an engine at operating temp would boil were it not for the system pressure provided by the radiator cap, which through a quirk of physics causes water's boiling point to rise. Remove the pressure, and it instantly can boil. When this happens, a quantity of the coolant turns to vapor and deprives areas of the block from direct contact with the coolant - a condition that normally would draw heat off the block. Localized hotspots, dramatic differences in internal block temperature (and resultant physical stress on the block) and overall low coolant levels result.

The starting and stopping is a difficult question. Starting and stopping a hot engine make for dramatic differences in internal block temperatures as coolant circulation stops and starts. When it stops, heat soak from normally occurring hot spots cause some areas temps to rise, others cool. When it starts, these areas are subject to the coolant flow and temps are evened out again. Whether this cycling would be better for the HG than to allow the engine to reach whatever peak temp the cooling problem would cause in a more uniform manner is difficult to say. My guess would be no. If the temp is rising or not leveling off below the hot zone by high idle then you're in for a tow in my book.

DougM

 

[turbocruiser]

Thanks Doug, that makes perfect sense. I actually remembered some old lessons and learnings from physics about pressure in sealed systems and how increasing pressure raises boiling point so that all made perfect sense, plus it was memory lane for me, so thanks for that too. Let's hope we wont worry with it but if that tricky temp guage starts spiking, its good to know the things to do!!! Thanks again.

 

[semlin]

good advice if it's just an overheat, but if you think it's the HG, I'm not so sure. I would think your first HG symptom may be a missfire instead of a temp spike.

a mechanic told me that if you blow a hg, pull over, stop the car and do not ever try to limp it. The more you run it, the more coolant you potentially let into the block. I respect the fact you may warp the head if you don't let it cool evenly, but they can machine the head. If enough fluid gets into the block you are cooked.

 

[turbocruiser]

[quote author=semlin link=board=2;threadid=17673;start=msg171563#msg171563 date=1086741032]

a mechanic told me that if you blow a hg, pull over, stop the car and do not ever try to limp it. The more you run it, the more coolant you potentially let into the block. I respect the fact you may warp the head if you don't let it cool evenly, but they can machine the head. If enough fluid gets into the block you are cooked.
[/quote]

Well, this is a very valid point, and I'm not trying to argue at all, but unless the HG has an absolutely catastrophic failure and is allowing lots of coolant in the block, I think its worth at least two minutes or so of on-the-side-of-the-road high idling with heaters on and so on. During this time, along with frantically monitoring the temp gauge, looking at things like belts and hoses and fan and fan clutch and radiator and radiator overflow tank and whatever, also look at the tailpipe; if it is spewing out steams of coolant, you know to shut er down and take the chance of warped head. Otherwise, just for arguments sake, (and I'd soooo loooove to hear what an expert like Robbie thinks with this), I think the way the HG frequently fails around that #6 coolant port means that the major worry would want to be the overheating of the head as opposed to the flooding of the block? That plus the fact that the overheating could be the fan or the fan clutch or the belts etc. Again, not arguing at all; I do not actually know the answer to this, I'm just asking. Thanks again, this rocks!!!

 

[RavenTai]

I don't see how running it after an overheat can help even for a soft failure? running cool (relatively) coolant through a overheated head is not exactly even cooling, it is rapid cooling and therefore uneven with the areas closest to the coolant contracting faster than areas further away inducing a lot of stress, it seams to me removing the heat source (turn it off) and letting it air cool over a longer period of time where all parts are a similar temp would induce less stress,

if the overheat was from a hard cooling system failure (loss of coolant, thermostat stuck closed, lost belt etc) and you continue to run the engine at any speed you are looking at extremely high temps that will likely warp and possibly crack the head

I have no formal education in liquid cooled engines there may be more to it than I can see

???

 

[Chris_Geiger]

CRAP!

All this talk about overheating... I think it caused a failure on my truck!

I just sprung a coolent leak right above the starter. Now it's leaking out as I drive. It's so tight in there I can't even see where leak in coming from. Next weekend I am going to pull out the starter to see if I can find the leak.

 

[ppc]

PHH more than likely.

 

[IdahoDoug]

Yeah, I'd go with the PHH or it's way more difficult cousin up at the firewall behind the valve cover. Bummer, but good thing you caught it before waiting for us to decide what the right thing to do when you're stranded is. Heh.

Hey, that's an excellent point Semlin makes on a HG failure. If you're getting coolant into the oil then I've also heard that literally minutes will determine whether you need an entire rebuild, or just head work. Antifreeze is simply murder on bearings and literally eats them if in the engine oil. I'm not clear. So, if it's suspected that the HG has failed suddenly then absolutely no question - shut down and call a tow. A measly tow bill would be less than sales tax on a rebuild.

DougM

 

[robbie]

Alot of good points brought up by many. Sorry to hear about the little heater hose Chris. It will mess thing up in a hurry if not taken care of. That is way I lost my HG many years ago.
Minor spikeing I would pull over turn off the truck and see what is happeing. Am I leaking, do I have enough fluid (the thermostat should be open and the coolant if enough will thermo cycle through the radiator). Look to see if the belts are ok and tight. if all looks OK, I would then turn on the engine and see what is happening with it running, If I have help I would run the engine up over 1krpms and have the person watch the temp guage. see what is up. then check out the fan clutch and look for little bubbles in the overflow tank. Then either make the choice to take it to a shop or fix it. IF slight bubbles I would drive it and make it home. Most 1FZ engine will not dump anifreeze into the engine. Most of the failures I have seen have been coolant being blowen out the radiator due to compression building up in the coolant system.
As for coolant in the oil, I beleive that it takes more than a little coolant in the oil to take out bearing. it take either lots of Coolant and some time period or a enough coolant to turn the oil milky and then running on it for a period of time. It does make a difference what the bearings are made out of. Different types of materials act differently. It always pay if coolant does get into the oil sump to pull the pan and check out the bearings. I see this more of a problem with the 22re with the timing chain digging into the water pump area of the timing cover that creates more problems then the 1FZ. IT may be best if you are not versed in reading the bearing surface to take it to some one that can see if the bearing is screwed up.

 

[krich97]

Turbo, not knowing much specifically about the 1FZ, I can't recommend a course of action if the HG has failed. However, I used to drive a 77 Bronco that did like to overheat occasionally, and I made a few observations. If I turned the engine off and waited 5 or 10 minutes, it was hard to start again and the temperature definitely spiked and would cool some after running at a high idle. When the engine is not turning the coolent is not flowing and the built up heat in the metal parts can only transfer to the coolent through conductive (less efficient) not convective heat transfer and of course radiant heat transfer from the outside of the engine (again without the benefit of fan induced airflow). Water has a high heat capacity and good deal of energy is consumed when water vaporizes, but once it does there is very little heat transfer from the metal to vaporized water (if there are pockets). What I found was that (assuming adequate coolent and fan function, etc) it helped to run at a high idle for a while (5 min) with the heater on of course if the needle is still climbing while doing this a shut down is in order (and probably a tow!) DO NOT REMOVE RADIATOR CAP for several reasons - the best one is that it is dangerous. The coolent in the block will be at or near boiling for some time after the engine is shut down (it will not be circulating though the radiator and cool down) Some cars continue to run their electric fans even when the engine is shut down, but I dont think the water pumps continue to circulate coolent.

 

[krich97]

Oh yeah, my wife was driving the cruiser yesterday after I made the dealer that mixed red and green when I first got it do a flush and replace the coolent at no charge. She picked up the truck so I did not even get a chance to look at it afterwards. I also had just replaced the fan belts. She got stuck in traffic for an hour hardly moving - it never occured to her to look at the temp gage. I am still worried she might have hurt my truck. I felt a lot of anxiety about whether the belts had stretched and loosened or if the dealer somehow messed up the flush or didn't put in enough coolent --- especially after the things posted here about HG failures and cooling system problems - thanks for makin me paranoid !!!!! I will probably have to change some hoses or flush the cooling system again so I can have good cooling system karma again. You are all too smart for your own good. Why can't we just drive around happy and ignorant like most of the folks we bot the cruisers from in the first place!!!!

 

[IdahoDoug]

That happy and ignorant stuff's for regular vehicle owners....

DougM