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superpowerdave
03-14-2007, 06:09 PM
Okay, after numerous issues with the cooling system on my 1973 Series III petrol, I noticed something new and exciting this afternoon ... the coolant was frothy!

I've flushed the system ten times over, replaced the thermostat, removed the thermostat, refilled, flushed again, replaced hoses ... not sure what's next? There isn't any oil in the water which I would have expected had I blown a gasket, just a frothy, chocolate looking mess when I pop the radiator cap when she's warm.

Suggestions? Thanks in advance fellas.

jason
03-14-2007, 08:03 PM
Sounds like either rust or Guinness.

oscar
03-14-2007, 08:58 PM
You SURE it's not oil? Frothy browish mess sounds like mayonaise (ie coolant with oil as emulsifier)...:confused:

59rover
03-18-2007, 07:14 AM
It certainly sounds like a head gasket. When you pull the spark plugs, what color are they? When the truck is running and warming up,( not hot) remove the rad cap slowy, can you see the coolant being pushed out does the level rise and fall? jim

superpowerdave
03-18-2007, 11:34 AM
Jim-

Yes, as a matter of fact, when I pulled the rad cap off while she was running it was like the coolant mess was being pushed up and out through the cap. I'm a little confused as to why I don't 'see' any oil in there.

As far as the head gasket goes, if that's what it is I'm relieved ... I'm just hoping it's not a cracked block or anything too major. How tough is the gasket change? Not major surgery or anything is it?

Thanks for the input guys, appreciate it.

Rob P
03-18-2007, 11:45 AM
Head gasket replacement is major surgery. It isn't for the weak of heart. You'd have to pull off the intake and exaust manifold and the head of the engine and scrape off the old gasket then clean everything up as best as you can. Sometimes even taking the head out to a machine shop to have it "shaved" to make sure it is flat. Then reassemble it all. Straight 4's, 6's and 8's are easier than V-motors but the process is about the same. Generalizing like I am at least. I've done a successful teardown and replacement of head gaskets on a 3.0L Chrysler minivan engine, you know, the one that smokes like mad. Had the valve guides replaced and the heads redone and the smoke went away. 6 months later something in the bottom of the engine let go. Oh well.

superpowerdave
03-18-2007, 12:31 PM
Jim-

Okay, took shots of the spark plug. Pulled the #1 plug, had some grease/oil residue on the threads. Does this look indicative of a head gasket blow-out?

http://bp2.blogger.com/_zwoZ1l4Kchs/Rf1oSFfDxrI/AAAAAAAAAMk/ikfpCUAXtF8/s1600-h/IMG_5191.JPG

59rover
03-18-2007, 05:52 PM
The photo of the plug is hard to tell, does it have a white residue on it? Can you see in the cylinders? If the coolant rises and falls, consistently pushing out air, and you say you have already changed the coolant,then the head gasket is leaking compression into the coolant system.If you pull the head, it is prefered to check for cracks and straightness. However, if the gasket is obviously blown or lifted at one area,many people use a good steel straight edge, visually check for cracks and back together.Having said that, the safe route is always the best.

oscar
03-18-2007, 06:39 PM
Level changes, bubbles is compression leaking into thr coolant. Mayonayse in the cranccase/valve cover is coolant leaking into the oil...brownish foamy greasy crap in the coolant is oil leaking into the coolant. It all depends on which ports have blown the headgasket between them....

replacing a headgasket is not excruciating if you have basic wrenching skills. The hardest part is getting the manifolds off without snapping or stripping anything. Start soaking twice daily with PB-Blaster or similar a week ahead of time....

Get a Haynes manual, generic as well as the Rover one and read up. It is important to gently loosen the head bolts in the order prescribed, and when reassembling fastening in the proper order. Make sure all the bolts can go in smooth and easy without the head, you don't want to be torqueing againts crud buildup.

As far as taking the head to a shop, I always do, to have it checked. Don't shave as a matter of routine, you can only take off so much. While you have it out check the valves, seats and guides. Are you setup for unleaded? Might want to take care of that while you're at it.