Calcium deposits on cams?

[Npdavies.]

Hey everybody, I've lurked here for quite some time and have never really contributed.

However, I need your help!

 

Yesterday we picked up a 1974 260z and started working on it.

One of the first things we did was try to turn the crankshaft to see if the engine was seized or not. After lots of elbow grease and torque we got it to move, and made it go a full rotation (mind you there is no battery in the car atm.)

The car has been sitting for 7-14 years and we figured typical things needed to be replaced (filters, fuel lines, etc.) so we got to work.

First thing was checking the brake and clutch master cylinders since those were what the seller said needed to be replaced. The brake master cylinder was full of black oily goo, so that was strike one.

Strike two was taking off the valve cover and low and behold found:

Which was certainly disheartening.

So our conclusion was that the head gasket was/is leaking water/coolant up into the camshafts and rusted and gross.

Any contribution would be greatly appreciated, thanks. :)

[datzenmike]

Na, just years of sitting in the damp. The 260 had some very poor carbs and maybe this is why it is sitting neglected. What are the plans? Body looks ok from here but if the motor is like that what are the rust prone areas like?

[Npdavies.]

We don't live in a typically humid climate, so I don't think atmospheric dampness would do much damage.

 

This is my first car so I'm planning on a rolling restoration. The body is in great shape aside from a little surface rust behind the hood and over the drivers side rear fender.

But the engine starting and not blowing up on me is my main concern at the moment. :P

[hogboy52]

Was the PCV valve disconnected? The crankcase vent plugged? That can cause a water/acid/oil mayonnaise to form atop the engine.

[datzenmike]

Did you drain the oil? What did it look like?

 

If you are going to rebuild, pull it now and disassemble it. Might as well know the bad news right away.

 

If you are thinking of getting it running to assess it. I would and leave the oil plug out. Wipe as much of that crud off as you can. Wire brush the rest and rinse with a good solvent. It will drain into and out of the pan with all the 'stuff.' Change the oil filter and half fill with new oil. Remove the oil pump and rinse out, refil level with fresh oil and install. Fill the motor with 40w diesel oil by poring over the cam and valve train and down the timing chain in front. It's very high in detergent and ZDDP anti scuff additives. Inspect the old plugs and replace them. Crank the motor over for 30 seconds and see if the oil light is out. If so we have at least 8 PSI and can assume the pump is drawing it up from the pan. Connect the coil wire and start it if it will. Short of rebuilding it, this will go a long way to getting good fresh oil to the crank bearings ASAP.

 

 

I seriously doubt it will with carbs sitting for this long. They (the infamous Z car flattops) must be in worse shape than the engine.

[ggzilla]

That's not calcium, is is aluminum corrosion. Like rust would be on iron.

[610racecar]

Did you drain the oil? What did it look like?

 

If you are going to rebuild, pull it now and disassemble it. Might as well know the bad news right away.

 

If you are thinking of getting it running to assess it. I would and leave the oil plug out. Wipe as much of that crud off as you can. Wire brush the rest and rinse with a good solvent. It will drain into and out of the pan with all the 'stuff.' Change the oil filter and half fill with new oil. Remove the oil pump and rinse out, refil level with fresh oil and install. Fill the motor with 40w diesel oil by poring over the cam and valve train and down the timing chain in front. It's very high in detergent and ZDDP anti scuff additives. Inspect the old plugs and replace them. Crank the motor over for 30 seconds and see if the oil light is out. If so we have at least 8 PSI and can assume the pump is drawing it up from the pan. Connect the coil wire and start it if it will. Short of rebuilding it, this will go a long way to getting good fresh oil to the crank bearings ASAP.

 

 

I seriously doubt it will with carbs sitting for this long. They (the infamous Z car flattops) must be in worse shape than the engine.

 

 

Excellent advice! I have started a number of vehicles which have sat decades using the above technique, most recently a 1970 Mercedes 6.3 that sat 20 years:

 

http://www.youtube.com/watch?v=BPxxETGumt8

 

Some additional points:

 

1. Pour a 50/50 mix of Seafoam and Marvel Mystery Oil into each cylinder and let sit at least overnight to help dissolve what is in the cylinders.

 

2. Crank the engine with the plugs out when you try to get the oil pressure up. This way there is no load on the bearings while the oil pressure is not there, and the crank speed will be faster.

 

3. Check a compession test if you get it running to look for a leaky head gasket. If it won't start, check a compression test anyway- I had a Fiat that sat for 25 years that had great spark and gas, but only 25 psi per cylinder.

 

Good luck and keep us posted-maybe a Youtube video of your first attempt to start it?

 

Marc in Indy

[Npdavies.]

And surprisingly enough, the carbs aren't the Hitachi flat tops, but rather something that looks like it's off an MG (which is the other car we have sitting in the garage)

But we haven't drained the oil yet, that'll be today.

We'll try out what you suggested Mike, thanks a lot. :)

[Npdavies.]

So we started to remove all 12 rocker arms today, cleaned them up and stuff.

Also cleaned all the 'mayonnaise' off the bearing casing on the camshaft and contemplated for a bit about taking out the camshaft entirely to get all the rust and whatnot off the lobes.

But that's a task for tomorrow. We're trying to keep as much of that out of the valves/head just to prevent any further problems.

Took off some smog stuff trying to get to the air rod but ended up messing with the throttle so some of that is going back on tomorrow.

Also removed the thermostat housing (Since it was so sealed we had to literally take it from the head) and found a pile of greenish-blue goop (which we decided was very coolant-looking) and a nice corroded spot:

(Sorry for the crappy pictures, ran out there to take them with a flashlight and my phone)

We're planning on fixing the broken spot with J-B Weld and getting a new thermostat housing.

 

Also took off my rear bumper last night and found a nice rust hole in the making, nothing out of control which is good. I think it looks pretty mean without all that rubber. ;)

 

Probably more things to be torn off tomorrow, I'll keep you updated.

[Npdavies.]

Got the car to start...

It was the timing.

And we figured that out after rebuilding the carbs... :P

[datzenmike]

What came first the chicken or the egg? You probably wouldn't have found the timing problem without rebuilding the carbs to get it running. Carbs that old are about 8 problems rolled into one. Rebuilding them was wise.

[Npdavies.]

What came first the chicken or the egg? You probably wouldn't have found the timing problem without rebuilding the carbs to get it running. Carbs that old are about 8 problems rolled into one. Rebuilding them was wise.

 

Yeah I figured that.

But it was still a little frustrating realizing that the firing order was all wrong. :P

But with the carbs, they were in fantastic shape. We took 'em apart, cleaned every nook and cranny, polished them and bolted them back on all puurrtyy.

The needle was sitting low so that had to be correct, aside from that everything was in tip-top shape (aside from gaskets obviously.) :P