Replacing just the head gasket. What else I need?

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velozi

Replacing just the head gasket. What else I need?

Post by velozi »

Had a valve job done 5000 miles ago but I now get a random sputtering while idle that can not fixed with the carb. Might be a small amount of moisture entering piston 3.

My question is what ther gaskets I can change at the same time I replace the gasket? Not planning on messing with the valves or anything else since all is working fine. Also, what is the process?

-Take out both manifolds or just exhaust one?
-Take out hoses and wires
-Remove bolts
-Make sure head is flat before installing gasket

Plan on replacing manifold gasket and replacing water hoses/thermostat. What else do I need?
So Cal Mark

Re: Replacing just the head gasket. What else I need?

Post by So Cal Mark »

you don't need to remove either manifold to pull the head, just disconnect the pipe at the flange. It's easiest to have a helper to lift the assy off; one on each side of the car
majicwrench

Re: Replacing just the head gasket. What else I need?

Post by majicwrench »

I would make darn sure you really need to replace the head gasket. Head gskt has nothing to do with sputtering. Might be moisture in #3?? Make sure.
And, if indeed head gskt problem, why did it fail in 5k?? Take your time, make sure of your diagnosis.
Keith
baltobernie
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Re: Replacing just the head gasket. What else I need?

Post by baltobernie »

velozi wrote:Had a valve job done 5000 miles ago but I now get a random sputtering while idle that can not fixed with the carb. Might be a small amount of moisture entering piston 3.
Are you seeing coolant residue on #3 spark plug? How about a photo of all 4 plugs identified?
velozi

Re: Replacing just the head gasket. What else I need?

Post by velozi »

Now that you say moisture in #3, that is what I was told it was. So moisture is not related to a small failure of the head gasket?
The head gasket has never been replaced, just the valve cover gasket as part of a full valve job.

If it is moisture in a cylinder, what to do before assuming a head gasket?
joelbert2k

Re: Replacing just the head gasket. What else I need?

Post by joelbert2k »

I must have missed something here. But, how do you do a valve job without removing the head :?:
Did you maybe do something else and thought it was called a valve job?

Joel
velozi

Re: Replacing just the head gasket. What else I need?

Post by velozi »

I have a receipt from PO that states a full valve job. A while back I asked about the head gasket and he told me that it was the original. So not a 100% sure of what was done.

The problme is sputtering at low RPMs in a random manner. Fiat mechanic in GA stated that it sounds like a small water moisture crack in the head gasket. No loss of power or gunk in oil or coolant.

Changed plugs, distributor cap, wires, points, rotor and coil but still same thing. Also carb adjusted in a lot of ways but still same thing.
narfire
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Your car is a: 1980 124 spider
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Re: Replacing just the head gasket. What else I need?

Post by narfire »

When the valves were done the head would have come off the car and when the head was put back on, a new head gasket we all hope, was used. After the initial torque of the head bolts,it was suggested to me drive the car for a few hundred kilometers and then re-torque to the spec'd ft-pds. Was this done? do you know/remember.
I'd like to think the person doing the valves would have checked the head for a flat surface,regardless, the few bucks to shave 5 thou or whatever is needed(to a point) to get a known flat surface I think is a good idea.
Do you know what kind of moisture was in the cylinder? oil (rings perhaps)(valve seals? if they were not replaced) anti freeze/coolant? All the heater hoses tight and intact,no leaks dripping into the plug recesses-plugs tight?
Majicwrenches idea of trying to find out what is the cause before pulling the head is a good one. Perhaps try a compression test.
Removing the head is not a big deal,you will need/should replace the head gasket though. A new timing belt should be used as well when putting it all back together. (I try to remember to have the engine at TDC before pulling the head, easy to set the cams & line up when putting back on)
Let us know if you do a compression test and what you find.
Good luck,after sorting this,you'll love the car just that much more :mrgreen:
80 FI spider
72 work in progress
2017 Golf R ( APR Stg. 1)
2018 F350 crew long box
So Cal Mark

Re: Replacing just the head gasket. What else I need?

Post by So Cal Mark »

I'm betting a valve ADJUSTMENT was done, but the whole thing sounds suspect including the diagnosis of a leaking head gasket
narfire
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Re: Replacing just the head gasket. What else I need?

Post by narfire »

Mark.. good point, if the valves were "done" (adjusted) the head would never have come off..
I just finished "adjusting" the exhaust side this afternoon on my car. (alot quieter now)
80 FI spider
72 work in progress
2017 Golf R ( APR Stg. 1)
2018 F350 crew long box
velozi

Re: Replacing just the head gasket. What else I need?

Post by velozi »

Went back to the records and found a 'complete engine rebuild', 'machine shop valves' and 'clean cylinder heads' listed.

This means the head was out and it should have a new gasket. This was 10k miles ago in 2001.

Sound in low rpms is like a small air escape noise at random but constant form.

The logic behind the diagnostic was a small amout of moisture getting into a cylinder that kills the spark for one cycle on the piston. I will take out all plugs and see how they look, then look for signs of moisture in the ignition parts.
So Cal Mark

Re: Replacing just the head gasket. What else I need?

Post by So Cal Mark »

sounds more like a vacuum leak. If you were getting that amount of coolant into a cylinder you would have steam out the exhaust pipe and water in the oil
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Re: Replacing just the head gasket. What else I need?

Post by baltobernie »

velozi wrote:The logic behind the diagnostic was a small amount of moisture getting into a cylinder that kills the spark for one cycle on the piston.
Not possible; small amounts of ingested coolant will perform the same as "water injection", as used on military piston airplane engines, etc. Actually makes more power, not less.

You're on the right track. Examine all four plugs; see how they compare to each other:
http://www.ehow.com/video_2326961_crack ... plugs.html

The second part of this video shows how to pressure-test the cooling system.

If you can hear air sounds with the engine running, it is, as Mark suggests, likely a vacuum leak.
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