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Well, here we go again (Blown HG)!!
#1011171
10/18/10 01:39 AM
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Joined: Oct 2007
Posts: 212
OP
Wheeler
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This is the second one I've blown on my '94 22re. I just confirmed it by doing the chemical test (exhaust gas in cooling system).
I did a compression test (cold):
1: 140 2: 140 3: 145 4: 175
I have judiciously set the valves and made sure the head bolts (AARP) are were tight after I replaced the head and gasket 2 years and 20,000 miles ago.
When I start it up the engine runs real rough like it is rich; then after a bit it smooths out and runs normal. I can hear what sounds like a rod knocking when I first start it up and its running rough, but after the engine smooths out the knocking goes away.
The million dollar question is what caused this? The first time that I noticed something was wrong was when I was towing the trailer down the highway. When I came to a red light the temp gauge started going up. That happened a few times, but it seemed to always stay in the normal range when moving at a decent speed.
I also noticed when I got home that first day after it blew, that the coolant was boiling (or at least it sounded/seemed like it). However, the temp gauge showed that it was not too hot. So, I thought that maybe the radiator cap needed replacing. I replaced it, and I haven't heard that boiling sound since even when the temp gauge shows that things are getting hotter than normal.
Also, the engine is losing coolant, but it does not appear to be leaking out or being blown out through the reservoir. The cooling system is definitely being pressurized by exhaust gases, but not as badly as the last time the HG blew (two years ago).
Cooling fan:
Yesterday when I got home the temperature gauge was getting up there again, so as soon as I got home I checked to make sure the cooling fan was working. It wasn't. I suppose it needs some of the liquid stuff in the fan clutch that seems to leak out over time. I am running a 3-core radiator that is still rather new. I also have a dual valve thermostat from the dealer.
So, I'm not sure if the HG blew which put air into the cooling system which overheated the engine OR the engine overheated due to either (or both) a bad radiator cap or a faulty cooling fan clutch.
Bottom line is that I'm at a crossroads whether or not I should slap another HG in it and see if it will go another 20,000 miles, or if I should get a replacement. The bottom end is untouched, but the head is a newer EB head with O/S valves.
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Re: Well, here we go again (Blown HG)!!
[Re: outdoorfan]
#1011172
10/18/10 07:33 AM
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Joined: Nov 1999
Posts: 1,049
Body Damage is Cool
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What did you torque the HG down to? I always go 65-68 ft-lbs. Seems to hold better. What gasket did you use? I presume it was a new head? Did you clean the block deck thoroughly? Some hold longer than others, it seems <img src="/forums/images/graemlins/shiner.gif" alt="" />
Last edited by toyrunner; 10/18/10 07:33 AM.
1985 SR5 4Runner eLocked with Carter Lock 4.7:1 single case Davez Offroad twin stick
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Re: Well, here we go again (Blown HG)!!
[Re: toyrunner]
#1011173
10/18/10 02:00 PM
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Joined: Oct 2007
Posts: 212
OP
Wheeler
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ARP head bolt studs and nuts go to 80 ft/lbs, I think. I used the gasket supplied by EB (Rock, if I remember correctly). New Topline head supplied by EB. I cleaned the block. There was some warpage to the block deck, but it didn't seem to be out of line. What did you torque the HG down to? I always go 65-68 ft-lbs. Seems to hold better. What gasket did you use? I presume it was a new head? Did you clean the block deck thoroughly? Some hold longer than others, it seems <img src="/forums/images/graemlins/shiner.gif" alt="" />
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Re: Well, here we go again (Blown HG)!!
[Re: outdoorfan]
#1011174
10/19/10 04:44 AM
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Joined: Apr 2005
Posts: 525
Rock Warrior
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judging by your compression test results, you'll probably find coolant in your #4 cylinder, obviously. the "boiling" sound you're hearing is most likely gurgle from combustion gases pressurizing your cooling system. be careful running it like this. last time mine went, it was a slow process and in the end, I blew two cooling hoses while I was away from home before I realized what was happening. looking back, I was just in denial, and I hadn't seen or smelled the coolant burn. the first time, I was able to make a repair. the second time, it was the upper main hose, and luckily I was very close to home. ![[Linked Image]](http://i125.photobucket.com/albums/p47/msgvb/car-truck/upper-radiator-hose-blown.jpg) EB's head gaskets are turbo gaskets, if I'm not mistaken. (I also have an EB head) how did you go about cleaning the block? I use green scrubby pads and brake cleaner after scraping off most of what I can. my understanding is that the mating surfaces have to be clean-clean. did you chase out the bolt holes and blow them out? you used the special lube on your ARP head studs? and did you double-nut them down into the block before final torquing? by warped, do you mean the block is warped, or your old head was warped? you do have the two dowel pins installed in the block, correct?
Last edited by yodta; 10/19/10 02:26 PM.
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Re: Well, here we go again (Blown HG)!!
[Re: yodta]
#1011175
10/19/10 04:22 PM
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Joined: Oct 2007
Posts: 212
OP
Wheeler
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judging by your compression test results, you'll probably find coolant in your #4 cylinder, obviously. Yeah, that's probably where it's going. the "boiling" sound you're hearing is most likely gurgle from combustion gases pressurizing your cooling system. Yes, I am getting that too, but that initial "boiling noise" was different. I didn't hear it again after replacing the radiator cap. be careful running it like this. last time mine went, it was a slow process and in the end, I blew two cooling hoses while I was away from home before I realized what was happening. looking back, I was just in denial, and I hadn't seen or smelled the coolant burn. the first time, I was able to make a repair. the second time, it was the upper main hose, and luckily I was very close to home. The first time the HG blew it gradually over time built up more and more pressure in the cooling system until it blew the upper tank of the radiator right off its seem. ![[Linked Image]](http://i125.photobucket.com/albums/p47/msgvb/car-truck/upper-radiator-hose-blown.jpg) EB's head gaskets are turbo gaskets, if I'm not mistaken. (I also have an EB head) how did you go about cleaning the block? I use green scrubby pads and brake cleaner after scraping off most of what I can. my understanding is that the mating surfaces have to be clean-clean. I took my time. It was very clean. did you chase out the bolt holes and blow them out? Yep. you used the special lube on your ARP head studs? Yep. and did you double-nut them down into the block before final torquing? No. I don't remember reading anything about doing that. There are allen heads on the tops of the studs (if I remember correctly), and I don't think they need to be super tight. I checked and retorqued the stud nuts several times just to make sure they stayed snug. by warped, do you mean the block is warped, or your old head was warped? The new head at the time was a brand new Topline from EB. The block was not resurfaced, and it was slightly warped. Not bad, but it wasn't perfect and could very well be the reason why this happened. you do have the two dowel pins installed in the block, correct? I ordered another gasket set from EB, and I think I'm gonna just replace the HG (after getting the head slightly touched up) and hope it makes it through the winter, at which point I might be in a better position in the spring to make a move on something else. Unless, of course, "something else" falls on my doorstep in the meantime. <img src="/forums/images/graemlins/rolleyes.gif" alt="" />
Last edited by outdoorfan; 10/19/10 04:31 PM.
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Re: Well, here we go again (Blown HG)!!
[Re: outdoorfan]
#1011176
10/19/10 07:17 PM
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Joined: Nov 1999
Posts: 1,049
Body Damage is Cool
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Most definitely clean out the head stud/bolt holes and blow out with compressed air. I run a thread chaser through them to final clean. It will make the world of a difference. Good luck.
1985 SR5 4Runner eLocked with Carter Lock 4.7:1 single case Davez Offroad twin stick
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Re: Well, here we go again (Blown HG)!!
[Re: toyrunner]
#1011177
10/19/10 10:00 PM
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Joined: Oct 2007
Posts: 212
OP
Wheeler
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Most definitely clean out the head stud/bolt holes and blow out with compressed air. I run a thread chaser through them to final clean. It will make the world of a difference. Good luck. Yep, I did that. Thanks.
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Re: Well, here we go again (Blown HG)!!
[Re: outdoorfan]
#1011178
10/19/10 10:24 PM
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Joined: Jun 2003
Posts: 3,576
Roll Me Over
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Most definitely clean out the head stud/bolt holes and blow out with compressed air. I run a thread chaser through them to final clean. It will make the world of a difference. Good luck. Yep, I did that. Thanks. >>>*I would be somewhat concerned with the mention of the block being mildly warped? It doesn't take much upset with clamping force variations since these engines are an Aluminum head on a cast iron block, lots of expansion rate difference there....*EB
*Beats the he** outa me!....*LOL**...
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Re: Well, here we go again (Blown HG)!!
[Re: outdoorfan]
#1011179
10/21/10 03:06 AM
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Joined: Apr 2005
Posts: 525
Rock Warrior
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and did you double-nut them down into the block before final torquing? No. I don't remember reading anything about doing that. There are allen heads on the tops of the studs (if I remember correctly), and I don't think they need to be super tight. I checked and retorqued the stud nuts several times just to make sure they stayed snug. okay, that's new since I last had ARP head studs. unless I put every single one in upside down and didn't notice the allen heads. that's a nice idea. the double-nutting technique was just to get them properly driven into the block, but yeah, I don't think they needed to be, maybe are not even supposed to be, very tight. x2 on the block deck. but not like you needed my opinion on that after EB pops his head in to sound off on the matter <img src="/forums/images/graemlins/smile.gif" alt="" />
msg - '87 xtracab
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