Bumping this thread because I just found a hairline crack in almost the same place seeping oil. I only have 2k since hg was replaced and it did not overheat. It's possible it overheated on previous owner though. Any thing new since this thread? I am contemplating a patch because head reallacement just isn't feasible right now. I don't think the crack is critical, just a nuisance since its leaking oil and I just resealed the whole motor.
Hairline Cracks In Cylinder Head -- Advice Please!
- Thread starter brukshut
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Had a tiny crack in almost the same place on mine about 18 months ago - opted for a band-aid approach and cleaned it VERY well and JB weld - no weeping to date. Plan on putting a diesel in in the future so cant justify $$$$ in a head replacement.
http://www.permatex.com/products/In...x_PermaPoxy_5_Minute_Aluminum_Epoxy_Stick.htm
I'm thinking about trying this. I have been thinking about a 4bt swap in the future also, so I don't want to replace the head especially since it was just off.
I'm thinking about trying this. I have been thinking about a 4bt swap in the future also, so I don't want to replace the head especially since it was just off.
With as small a crack as that one, I would simply weld it. However I wouldn't do it in the vehicle, I would only do it in the shop with access to an oven where you can preheat the head. I would also think about clamping the head to a welding table to simulate the stress of being bolted to the head, but in the case of the small cracks along the valve cover rail, its not that big an issue. Weld it up and call it good.
I would be much more concerned if the crack was really deep in the head casting, but it is in the upper valve cover rail so its more than likely from repeated heating and cooling cycles over the length of the head surface. I suspect a new head would do the same thing in 150K miles. Remember we have a really long engine and that surface is subject to a lot of stress when heated and cooled repeatedly.
I would be much more concerned if the crack was really deep in the head casting, but it is in the upper valve cover rail so its more than likely from repeated heating and cooling cycles over the length of the head surface. I suspect a new head would do the same thing in 150K miles. Remember we have a really long engine and that surface is subject to a lot of stress when heated and cooled repeatedly.
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- #49
Folks --
As this was my original posting thought I would provide a quick update. I opted to seal up my cracks with some JB Weld. I am now a bit concerned about the head after reading the posting that quoted the machine shop mechanic at Watkins Glen saying ditch the vehicle ASAP. Guess I gotta bump this up my priority list.
My truck has 80K original miles on it; I'm most likely gonna but a new OEM head as well as a new set of headers and exhaust (pacemaker headers or some Aussie brand). I personally like the inline 6 so I'm gonna try and squeeze as much out of it as I can.
As this was my original posting thought I would provide a quick update. I opted to seal up my cracks with some JB Weld. I am now a bit concerned about the head after reading the posting that quoted the machine shop mechanic at Watkins Glen saying ditch the vehicle ASAP. Guess I gotta bump this up my priority list.
My truck has 80K original miles on it; I'm most likely gonna but a new OEM head as well as a new set of headers and exhaust (pacemaker headers or some Aussie brand). I personally like the inline 6 so I'm gonna try and squeeze as much out of it as I can.
I've now got over 10K miles on it and have ignored it since noticing it. Nothing has changed, engine still runs great, can't detect any oil loss on the dipstick between oil changes ~3K mile intervals, etc. I plan to epoxy it and forget it.
I picked up an LX450 a few months back and it had a burning oil smell. Figured it needed a valve cover gasket so I cleaned everything up to try to pinpoint the leak. Turned out the head was cracked. I took @pinhead's advice and smeared some FIPG on the leak. Been about a month now and no leakage.
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If anyone is looking - Amazon has http://www.amazon.com/Genuine-Toyota-00295-00103-Formed-Place/dp/B000EDDTV0?tag=ihco-20
I always keep a couple of tubes on hand. Just in case.
I always keep a couple of tubes on hand. Just in case.
About a year or so ago I picked up a used head to replace this cracked one. Well, as luck would have it, my head gasket popped so I got the opportunity to pull the cracked head and replace it. I took a few pictures but I'm a poor photographer so they aren't great but what they do show is the crack propagated quite a ways down the head. At every heat cycle this is opening up and probably growing over time. While I suspect this could be welded I'm not sure it is worth the effort. Pictures are of two different cracks.
@Crashdix how's it holding up after all these years? Having a similar issue!!!! Same circumstances...newly rebuilt motor and head. Noticed same hairline crack a few thousand miles later.
When you solve this problem, let me know how you did it I have something, I use a sponge and wedge in there to absorb the oil
I'm curious how many folks have this exact problem and seeing as it's only a somewhat minor leak on a truck that is prone to leak from multiple places just sort of figure it's a slightly bad valve cover gasket and move along
Yeah, I think you wouldn't really notice it unless you have OCD and your engine is all clean. The amount of oil that leaks is minimal. So far most of the people I've seen with these cracks are all in the same general location.
I was fine with using the FIPG, worked for me for almost three years and then the head gasket blew so the head had to come off.
My point was that after removing the head there is no way I would reuse it without getting it repaired, and to me that means welding. Not saying Loctite or JB weld wouldn't work but not a risk I would want to take if I was reworking the head.
My head has two cracks and there may even be more. I don't think repairing it is worth the money.
@TomH curious how you got the FIPG to work. I tried and it seeped past it. I tried to clean it very well. Used brake cleaner even. Let it sit for a day or two. Used compressed air....then applied FIPG. Didn't work. Maybe I just got unlucky. What was your method?
You know, maybe I'm imagining that it worked. Maybe it slowed the leak a little. I suppose what really worked was whenever I started smelling burning oil I would grab a rag and wipe the head down to keep the oil off the exhaust manifold.