Head Gasket Replacement

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Otto Skorzeny
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Re: Head Gasket Replacement

Postby Otto Skorzeny » Wed Jul 21, 2021 6:13 pm

That's a good deal.

I also got another suggestion for blocking the heat riser from a mechanic I trust.

Pack the passages with stainless steel wool and seal the ends with refractory cement. The refractory cement step can be skipped if you want.

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roland
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Re: Head Gasket Replacement

Postby roland » Wed Jul 21, 2021 10:36 pm

...Separate gaskets with the passage blocked off are available but I think the valley pan is useful in keeping crud off the bottom of the intake...


You can use those gaskets without any problem.
The reason to use the full valley pan gaskets is to keep away engine oil from the overheated chamber at the bottom of carburetor. This crossover passage can be nearly as hot as the exhaust manifolds if the exhaust valve don´t work properly and spitted oil or oil dust burned up to coal/carbon/crud there. It is as the carbon build up on pistons with broken oil rings. The engine from Nicolas shows that clearly. His valley pan gasket was not really oil tight.
Is the passage blocked properly, the intake don´t heat up as before and no carbon will be there. Also without the full valley pan gasket.

If the passage is blocked with a good aftermarket intake manifold gasket or DIY plates the intake needs no addition work. I would not use the metal from an old valley pan. It is to thin to resist the heat for long time, I assume. I use 0,8mm stainless steel sheet metal to make my plates.
Roland TOA#860

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Otto Skorzeny
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Re: Head Gasket Replacement

Postby Otto Skorzeny » Thu Jul 22, 2021 8:35 am

Roland, how did you avoid a fitment problem with the block off plates?

If the gasket lays over them, it will be higher in the center than on the edges.

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roland
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1970 Ford LTD Country Squire 429
Location: bavaria / germany

Re: Head Gasket Replacement

Postby roland » Thu Jul 22, 2021 11:40 am

You have to cut or grind the new gasket at the places for the plates. The new gaskets are est. 0,8 to 1mm thick. The plates fit into the gasket with high temp silicone then. Don´t overlay them. I have no picture of that modification, sorry.
Roland TOA#860

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Otto Skorzeny
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Re: Head Gasket Replacement

Postby Otto Skorzeny » Thu Jul 22, 2021 12:28 pm

OK, that's what I was thinking. The plate should fit exactly in the hole of the gasket.

NicolasB
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Re: Head Gasket Replacement

Postby NicolasB » Fri Jul 23, 2021 8:50 am

I was thinking, can’t I also block off the crossover by welding it shut?

It's tough to properly weld cast iron. I'm going the 3000 degree refractory cement route.

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Re: Head Gasket Replacement

Postby NicolasB » Fri Jul 23, 2021 10:15 am

Nick, please post your question again. I accidentally deleted it.



Unless you are drag racing or auto crossing your car spending money on hardened valve seats is not necessary.

The minute amount of additional wear on the exhaust valves will never be noticeable - at least not in the normal lifespan of that engine.

I've been driving my '56 Cadillac as a daily driver on unleaded fuel for 20 years with no ill effects. By the way, unleaded fuel was introduced by AMOCO (their super unleaded product) in 1923 so this notion that cars never had to burn itr until 1974 is a myth.

Your car has been running on unleaded fuel for all but 4 years of its entire life. What do the exhaust valves look like? Probably like a normal engine with no unusual wear.

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Re: Head Gasket Replacement

Postby NicolasB » Fri Jul 23, 2021 2:14 pm

Shoot, sorry I honestly forgot what I asked earlier, but the machine shop did call me an hour ago and informed me that after inspecting the heads, the valve seats are still in good shape, but all the valves (intake and exhaust) need to be replaced (too worn). So that’s an extra $160 to the $220 to do a valve job on the heads and wash the intake manifold.

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Otto Skorzeny
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Re: Head Gasket Replacement

Postby Otto Skorzeny » Fri Jul 23, 2021 3:30 pm

Yes, you asked if you should spend money on hardened valve seats.

I personally think that would be a waste of money. As you've seen, your engine has normal wear and has been running on unleaded fuel for the last 47 years.

Your car has about 200,000 miles on it , right?

NicolasB
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Re: Head Gasket Replacement

Postby NicolasB » Fri Jul 23, 2021 4:21 pm

Okay cool, so I don’t have to worry about that anytime soon. I’m not sure how many miles my Toro has, since we don’t have any records of it from the previous owners, as well as the odometer not functioning.


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