%$#&*^!!!! What tools to rebuild head?

[Tangent]

Well I just finished swapping a used head onto my car after it broke it's timing belt at a disgustingly low mileage. The compression test results weren't pretty: (off the top of my head) 125 125 100 80 120 60

I'm guessing that the head either had a few bent valves or I just plain screwed something up. I followed the Bentley manual to the letter, but this was the first time I'd done head work so who knows where I might have done something wrong. After getting a quote of $700 for labor alone to rebuild a head it looks like the only way a head is getting rebuilt for this car is if I do it myself. (if the problem is even in the head...) Anybody have any tips on what else might be the problem or if it sounds like the head is dorked what tools will I need to rebuild it myself?

[AndrewBird]

Really all you can do is dissassemble and reassemble the head. You will have to take it to the machine shop to have it decked if needed, valve grind, etc.. The rest is pretty simple with really the only special tool needed is a valve spring compression tool. You will need to buy new valves to replace any bent ones, plus all the seals/guides etc.. that will be needed too.

Here is the tool:

http://www.sears.com/sr/javasr/product.do?cat=Mechanics+Tools&pid=00947627000&vertical=TOOL&subcat=Automotive+Specialty+Tools&BV_UseBVCookie=Yes

Are you sure there was no piston damage when you broke the timing belt? If the pistons were damaged in anyway, there could be compression leak down around the rings.

Did you torque the head down correctly? Could be leaking at the head gasket somewhere.

Was it the same head as before? If so, it most likely a bent valve. Breaking a timing belt does horrors on the valves.

If you do end up rebuilding the head, make sure you have it pressure tested before any other machine work is done just to be safe. It might end up being cheaper finding someone who is selling a good used head for cheap. Then all you have to do is swap it out.

[Sean]

Is it a 325is or...?

I have a head here from a SuperEta, good condition from what I believe, I casting. All it needs is dual valve springs and I cam to work with I.

I'm selling it for like $230 shipped I think?

If you wanted, you could take both your old and head and mine toa shop, tell them to swap the parts I mentioned and do valve seals at the same time.

I dunno - probably just as expensive as buying new valves, lol

But throwing it out there.

[Tangent]

The head was off the 325i I'm parting out which I was told ran fine before the owner curbed it and broke the oil pan and steering rack. The pistons appeared to be fine, all the visible marking on them was carbon was knocked off the valve reliefs on a couple of them. I was very careful about torqueing the head exactly per the Bentley maual's specs. I used new head bolts and torqued them in the recommended order to the torque spec, then in order to another 90* twice. There's no way to tell with a compression test if it's the valves or the piston rings is there?

The head that was originally on there definitely has bent valves. I figure if I can rule out a dorked block/pistons, I'll rebuild that head with all new valves, springs, etc... I'll definitely have it tested befoer I buy anything.

[Sean]

The head was off the 325i I'm parting out which I was told ran fine before the owner curbed it and broke the oil pan and steering rack. The pistons appeared to be fine, all the visible marking on them was carbon was knocked off the valve reliefs on a couple of them. I was very careful about torqueing the head exactly per the Bentley maual's specs. I used new head bolts and torqued them in the recommended order to the torque spec, then in order to another 90* twice. There's no way to tell with a compression test if it's the valves or the piston rings is there?

The head that was originally on there definitely has bent valves. I figure if I can rule out a dorked block/pistons, I'll rebuild that head with all new valves, springs, etc... I'll definitely have it tested befoer I buy anything.

Sounds like that's the way to go for sure!

[nando]

other than a valve spring compressor (~$20 at sears) I didn't need anything special to do mine. all the machine work was already done, but you can't do that with hand tools at home anyway.