Loose Head Bolts

[SteveK]

I've been loosing a little water and last week I saw some bubbles in the oil when I pulled the dipstick so I thought that I had blown the head gasket.   I went through and read all of the threads and decided to start by taking Joe's reccommendation to try tightening the bolts before you embark on a head gasket replacement project.  I did it this afternoon and was shocked at how loose my head bolts were.  I suspect it took less than 30 or 40 pounds to break each of them loose.  I followed the procedure and re-torqued them one by one.  At 80 ft-lbs, all of them twisted in at least one full turn further than they were before I started.  It's an easy 1 hour project which could save some real hassle.  (time will tell if I was too late in my case! )

[ja17]

Hello Steve,

Hopefully this will work.  As long as the leak has not eroded away the head gasket or aluminum head, you stand a good chance.

[waqas]

It's my understanding that even a slightly eroded gasket can lead to accelerated damage of the head itself. (rounding the sharp edges near a gasket leak).

In other words, even if the leak seems to be cured, wouldn't it be a good idea to just go ahead and replace the gasket before more damage can occur to the head itself? (assuming it's not damaged already)

[lurtch]

Hello Steve,      I had a problem with loose head bolts also. In my case the severely advanced corrosion in the water passages allowed coolant to enter and  fill up the clearance surrounding around the head bolt. There was also corrosion down into the threads in the block, but I have so far been able to milk another 5K miles out of this situation - -  but the end is near. Needless to say, this head became scrap metal. Good Luck with yours.

Larry in CA

[ja17]

Hello,

This type of corrosion can also be caused infrequent anti-freeze changes.  It becomes acidic eventually and eats away at aluminum!

[Benz Dr.]

I can't even begin to describe just how difficult it is to remove a cylinder head when the head bolts get siezed. I was able to save the engine but it added a lot of effort to the job.

Usually removal of engine parts goes OK with only small screws being any real problem and lots of heat will take care of those problems. But stuck head bolts can be VERY difficult to remove. If you're lucky, you can heat the block right where the bolt is stuck until it starts to smoke and hope that the screw will turn out. In my case I went right though the opened side cover and applied heat around the casting where the bolt was still stuck.

[SteveK]

lurtch, that head looks pretty scary.   I had a 280c for about 15 years.  At around 175,000 miles I pulled the head for a valve job and found similar corrosion (not quite as bad as yours however).   I brought it to a shop in Houston where they ground it out, welded it up, machined it and did the valve job.   I drove the car for 50,000 more miles  before I donated the car away!

After re-touquing my head on Saturday, yesterday I changed the oil (which didn't look bad) and then drove the car for a few hours.   So far, no loss of water.  I also changed the expansion tank cap so that may also have helped.

[graphic66]

Looks like  electrolysis. Bad grounds and stray electric can cause this. Good idea to check for this before it happens. Pretty simple check and possibly a simple cure.