Contra472

So did he actually use a machinists straight edge to check for warpage of the head? If so, was it within tolerances? Or did he just eyeball it?

The reason I ask is because I over heated my truck too, and although it didn't blow a head gasket, it did warp the head and caused an external coolant leak.

Seems like it's pretty easy to warp the head if it overheats, which would require shaving to fix it right.

Also, were the head bolt holes cleaned thoroughly with a chase? You mentioned carbon build up on the bolts, so if the bolts and holes weren't thoroughly cleaned, that 59ft/lb really isn't, and may contribute to failure.

Was the deck and head surfaces properly cleaned?

nordicwargod

The machine shop I go to pressure tested a head I had that was defective. The crack/leak was inside and may not have been found with another inspection method.
You have to do some research on the block specs as I can't find them. The head spec for flatness is six thousandths. This may be the spec for the block too, but the two combined has a tolerance too and you have to know that.
After re-reading your last post about replacing the gasket and it immediately leaking I sympathize. It can't be the intake manifold, no oil there. Can't be the timing cover because it can't get into the cylinder that way. It has to be the head gasket, head, or possibly the block which is kind of a reach as these blocks are tough. Much tougher than the head.
If a problem is found price things out. Don't mill the head first! If there is a problem with the head you should know that you can get a NEW fully assembled head with new valves, seals, and guides delivered to your door for $350. We are lucky that heads for these are inexpensive..

wwjr

I honestlycan't say for sure about anything regarding the head or block. I was a bit shell shocked when he called and said what had happened. I wish I could go to the vidiotape, but there isn't one


Seriously though, the old gasket looked shot but I just assumed that anyone doing this would make sure everything was done right so as not to have to redo it, you know? I am speaking of checking the head and the block for flatness. These guys restore old sports cars, and I know they must know that those things need to be done.


Not sure about cleaning the bolt holes on the head but I will pass that on.

wwjr

"The machine shop I go to pressure tested a head I had that was defective. The crack/leak was inside and may not have been found with another inspection method."


good info.

wwjr

Nordic...


How can the block be tested to make sure it is not cracked?

AKHeathen

you magnaflux it. this is usually done before you bore and rebuild it. if it's in the vehicle and an asembled engine, you pressureize the coolant and look for leaks while it's cold, while it is warmmed up some, and whaile it is hot. this may call for a scope to see via the spark plug holes..........speaking as a master mechanic with over 15 years professional experience, it is likely the head is heat warped. #1 problem is that the head bolts were worth mentioning..... if they were reuseable, they would be perfect, and unmentionable. replace them, no question. second: when a head gasket (or even exhaust gasket) leaks, the gas leaked is very hot, and creates a hot channel that can warp the surrounding metal. sometimes, it is perfectly fine, and unwarped, but sometimes, you get more leaks. if you have the cash, just mill the head like .020"-. o45". don't worry that much about cr with a stock motor, it was meant to run on under 80 octane, so detonation is not an issue. have the block checked with a strait edge. you don't want to find warpage on that cylinder that leaks. your mechanic should have known to do this already. head gaskets aren't all that cheap, especially if you run mlm, or copper.. bottom line, the head comes of, the block checked for square, and new bolts minimum. i don't give the customer the option to run questionable bolts, either they are good or that are not.

nordicwargod

I ran into this a couple months ago. I have a engine that froze, its the one I had the head pressure tested and there were cracks inside that I simply tossed.
I asked the shop how to test the block and they replied that they can magnaflux it for external cracks but inside there was no way unless the block was x-ray'd which is thousands of dollars. Boeing x-ray's lots of their high stressed aircraft parts so you know that the equipment is very expensive.
I still had the block decked, bought a new head and installed it with a new/cheap gasket, installed the intake and timing cover and all the attached pluming. Caped off everything after filling it with water except for one hose and pressure tested it with a natural gas pipe tester at 25lbs with some compressed air. It held up to17lbs and then it started leaking out of the waterpump gasket which let me know that my timing cover needed some attention on the gasket surface. If any water would have dripped out internally I would have know I had a leak. Kept it pressurized for twenty minutes and came to the conclusion it was not cracked. Put in new bearings, piston rings after checking/measuring the bore and crank, and assembled the rest of the engine. Right now I'm double checking the cam timing because once you shave a bit off either the head or block or both combined you change the cam to crank timing. I'm doing this on my time off and double checking everything and writing everything down and comparing to the specs in the service manual.
Back to deck and head flatness: A very experienced friend that builds race engines told me that in his opinion if the head or block are off more than three thousandths each that he would have them resurfaced. Use a precise straight edge and feeler gauge, this was a little difficult for me as my set of feeler gauges only went down to four thousandths but my gaps were over 7 thousandths on the block and it took the shop several passes and they removed 12 thousandths to get all the low spots, pitting out.
I keep going back to your head gasket that failed the first time. Ask your mechanic if he checked it out for failure, it would tell you almost for sure if it was the gasket or if you possibly have a cracked head just by where it failed to let coolant into the cylinder. It could really send you in the right direction and you may not be guessing right now. Every amateur I know would know to do this, it would be one of the first things a pro would do. Good luck

wwjr

Wow! Thank you both very much!!!

AKHeathen

a good straitedge should be in every real mechanics tool box and rarely used.... but putting a head on, i always use. even a 24" edge on a clean block you should be able to at least use a flash light and feel. i can say, i've seen some freaky warped stuff hold, and some minor stuff fail. i say the mechanic really missed something here.

wwjr

I certainly wish the block and head had been checked better not only for level, but for cracks before putting it, and the new gasket, on. Pressure checking sounds like it would've been a smart option.


I hope the worse case scenario is a cracked head. A much better scenario would be solving the leak with just new bolts and having the head milled properly.

wwjr

final question...(I hope). Does one also magniflux the timing chain cover to test for leaks? My timing chain was replaced in April because the driver's side guide broke. I don't want to get the head gasket issue resolved and still have radiator fluid leaking into my oil.

nordicwargod

Well, I do know that there is a dye-spray out there that will expose cracks in aluminum, perhaps someone else can expand on this as I have never used it. Not sure aluminum can be magnafluxed either?
I know timing covers are cheap, you can get a good new one for $50 bucks delivered so there's always that. If you block has ever been decked though it won't fit. Have your guy check yours out, usually you can see if it has worn through. If you find out that you need to deck your block you should buy a new one anyway and it gets fitted perfect when the block is decked.

wwjr

thanks, nordic...good info.


I appreciate everyone's advice very much and will let you know how things turn out!

wwjr

Well, I FINALLY got my truck back today. It cost me $1,000. If the "mechanic" had checked the head properly before installing the new head gasket, this could've been avoided. He ended up charging me for twice the labor, oil, radiator fluid, and 2 oil filters and head gaskets!


The head milling charge was $160. for milling and replacing seals.


Lesson learned. Find a good mechanic even if you are dealing with an emergency situation. This is my only vehicle. All I can hope is that this resolves the problem!!


ps-the timing chain cover was checked and ok, and new bolts were used, but only after I asked for both.

nordicwargod

Did he check the block deck for flatness?

wwjr

To be honest, I've no idea. The past few days have been stressful as hell and I copied/pasted advice from this forum regarding that and sent it to him in an e-mail. I just took it for a drive and it runs good, but I will keep a watch on the radiator fluid and oil, and may even take it to someone else to have it pressure checked.

nordicwargod

If you drive it around at operating temperature that won't be necessary. Just check you oil and coolant. I hope this works out for you. First time I put one of these together it leaked. Didn't give the rtv time to set up and water leaked out into and out of intake. Learned the hard way that all surfaces have to be checked for flatness. More important than type of gasket, type of bolts, new bolts, old bolts. Surface preparation is the key when aluminum is attached to steel.

mwisham

More than likely, the head warped from the heat when it ran hot. The head is aluminum and will warp faster than the iron block would. You probably could get by with planing the head and putting a new head gasket on. You do not need to buy new head bolts. Just clean them up real well, chase the bolt holes in the block with a thread chaser, not a tap and put it back together. Your mechanic should have had the head checked before putting it back on. I would not think of putting a head back on without having a competent machine shop checking it out first.
The coolant will not damage your rod or main bearings unless it is allowed to stay in the oil for a long time. The coolant will leach the lead out of the bearings if allowed to contact them over a long period of time. Do as someone else suggested and change the oil after the first 500 miles of use after replacing the head gasket and that should get all remnants of the coolant out.
I use Seafoam in my 1980 20R at every fll up and I think it helps to keep the fuel system clean and also helps stabilize the gosh awful 10% ethanol they pass off as gasoline where I live. Put it in and never look back. Good luck.

AKHeathen

head bolts were replaced because the mechanic himself said they were "iffy" they aren't required to be replaced, but i've seen them bad as well. they are either good or they are not. you can end up with different clamping pressure, stretching or breakage.

wwjr

since the engine leaked after having the gasket replaced the first time, I didn't want to risk the bolts being a problem at all. as has been said, they were brought up as an issue, so why risk them being a problem the second go round. they aren't that expensive. had they been unmentionable, I would've never known.


what upset me was that something was obviously overlooked. the head should've been checked and, if necessary, milled before installing the first time. and, because it was not, whether bolts were a factor or not, I got stuck having to pay a hell of a lot more to get a job that should've been done right the first time.


the mechanic was even trying to talk me into replacing the engine and never once said, "I should've had the head checked and milled before I put it back on". that is what angers me. he never took any responsibility for his mistakes. a good mechanic would've said, "we have to have your head checked before we put it on, because it could be warped or cracked".


I won't rest easy until I've run this thing a while and taken it for a long drive at higher speeds to make sure there are no new leaks. I appreciate all the responses I've received and will post back in a couple days to update. hopefully all is well and I will have a good, dependable truck!