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Discussion Starter · #1 ·
how do you know if you should replace a headgasket on a motor. how do you know if the motor is in good enough condition to be worth it. run compression test I really dont know. plus I am not doing it myself so I would either buy A rebuilt head and put it on so the cost might not be worth it
 

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Question 1.
- Compression Test
- Oil and Coolant Mixing (Check Dipstick, or Drain Oil if necessary)
- Sweet Smell From Exhaust (some have told me sweat, some have told me rotten eggs, I believe it's sweet).
- Loss of Power

Your title says bad head gasket as if you know it's bad. If it's bad you should replace. If you don't know for sure if you have a BHG, why do you think you do?

Question 2
- Inspection of head and block while head is off.

Compression tests tells you likelihood of BHG, not if the motor is worth fixing the BHG haha. If you have a BHG, slapping a new head on will not solve, so either way head gasket must be in tip top shape.
 

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Discussion Starter · #3 ·
I have not worked on the car in in over two years. I forgot what conclusion of why I know the head gasket is bad. I am just starting to work on it again. No oil water mix on the dipstick supprisingly. runs like the cat is clogged in the cat I think oil started to leak out of one of the spark plugs but until I get more into it I cant remember. For not running for two years it reved pretty good yesterday but I know there is A mojor problem with the motor and I found it years ago to be the headgasket
 

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do you mean that oil is actually on the spark plugs, or that there is oil in the valley, between the 2 camshaft housings?
The camshaft housings have a bad tendancy to leak oil on top of the engine,
and it has nowhere to go.
It is not common to have oil feed from the spark plugs holes.
 

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You might try putting in new plugs, run it a while, then, inspect said plugs. One or two coated in oil means worn rings perhaps.
 

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Bad Idea

If you ever plan on actually working on the car in the future this stuff probably isn't a good idea, unless of course you don't mind having the head welded to the block. These products are great for a fix on a car that's on its last leg and you are just trying to make it a few hundred more miles before it goes to that great salvage yard in the sky. But if you plan on ever rebuilding the engine, chances are after this you wont be able to.

A great example is we used it to fix a front end loader in the winter when it was needed and planned on fixing it right in the spring.. well come spring and we couldn't even get the head off with another loader.
 

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Never "Half ass" a job this important. You would be a lot better off to just stick a new one on it, and be done. Me and Johnb7 had mine replaced in a day.
 

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You would have oil mixing in you coolant. Because when you blow a head gasket you have oil and coolant passage that are leaking between each other so to speak (hard to explain). Also, those passages are leaking into your combustion chambers.

So you have coolant burning in you exhaust.

Best ways to tell if it's a blown head gasket is to check your oil for water. Change your oil, and inspect the oil for water. It should look black. If it looks like a milkshake you have blown head gasket. If you DO have milkshake oil, you need to cut open you oil filter and check for metal shavings.

When you have water in your oil, it eats away at your rod and main bearings over time if you don't fix it. That metal that is being eat at won't pass through your oil filter. So cut it open and look for any shiny metal. This means possible rod or main bearing damage.

Which isn't good. When you remove the head off the engine to replace the head gasket, go ahead and drop the oil pan and check the rod and main bearing clearances. If they are out of spec you need to have new bearing and possibly machining.

TO figure out if you need your crankshaft machined, remove your rods, and take your fingernail across the journals of the crankshaft. If you can feel a dip, grove, or it's not smooth, you need to remove the crank, and take it to a machine shop to have it balanced and polished.

Hope this helps. Also when you replace the head gasket it's always best just to buy a headgasket set with these old cars, replace the timing belt, check valve clearances, and replace the rear main seal.

Matt
 

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Fastspool's comments seem a little unclear to me, so I'll say it the way it works for me and hope we're saying the same thing. :)

If the BHG is between a coolant passage and an oil passage, then you can have oil in the coolant or coolant in the oil.

I have personally had (on 5M and 7M-GTE) a BHG from coolant passage to cylinder. (the sweet smell) Usually #6

It's conceivable to have a BHG from oil passage to cylinder. (burning LOTS of oil).

I'd check compression first, even just for giggles, that'll tell you if a cylinder is compromised (which from your description (no coolant in oil) I would assume) and honestly, that's the best possible outcome of a HG going bad.

Unless you have oil all over the underside of you hood and a *very* loose sparkplug I'd say RedP85 is right on about where the oil is coming from in the valley between the towers. Otherwise, your engine would have hydrolocked and you'de most likely be looking for a whole new engine.

If you need it, I can dig through my tools and send up the compression tester. Gimme a call or PM.
 
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