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Discussion Starter #1
After a year of trouble free driving my 1986 Spider is demanding attention. I have taken care fo the easy items already, new brakes and a new exhaust system (wow, the new exhaust made a big difference).

Now the hard task is replacing the head gasket, which is leaking oil all over the place and the radiator fluid is starting to show the oil. I have decided to do the job myself. I have the shop manual and Pat Braden's Owners Bible, but sure would apprciate any advice.

Is there a particular head gasket that is recommended or O rings?
How do I get the engine to top-dead center, should I role the car in 2nd gear?
Should I order a new valve gasket at the same time?
Should I (do I have to) do anything with the valves while I have the head off?

I appreciate any tips.
 

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Is there a particular head gasket that is recommended or O rings?
Dunno about the gasket proper, but the 'square cut' viton o-rings are supposed to be the shizznit. (pins might not hurt to have either)

How do I get the engine to top-dead center, should I roll the car in 2nd gear?
Actually, with all the plugs out and trans in neutral, you can turn the engine by pulling the fan. (unless it's really old and brittle, in which case it'll just break)

Should I order a new valve gasket at the same time?
Yes, but check to see if mabe it's part of the top end gasket kit first so you don't end up with two.

Should I (do I have to) do anything with the valves while I have the head off?
It never hurts, but it depends on how far you want to go.

Certainly a good inspection with mabe a re-lap of the seats, or you could go all the way up through a total rebuild.

Depends on how carried away you want to get or if there's time constraints involved.
 

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There are lots of good threads about replacing the head gaskets here. There will be many opinions about head gaskets & O-rings. Weigh your options and make your choice.

Reinz is the head gasket I used - so far so good (~ 1 1/2 years/25K miles).

You can easily turn the engine with the spark plugs out and the gearbox in 4th speed. TDC with #1 on its compression stroke is a good place to position the crankshaft. Remove the cam cover. When the #1 cam lobes are facing away from each other (intake pointing right and exhaust pointing left) and the #1 piston as high as it will go (peek in the spark plug hole &/or use a drinking straw to note its position) the #1 is at TDC on compression. There should be a pointer at the bottom of the water pump aimed at a 'P' mark on the crank pulley. But since that pointer is adjustable it can also be mis-adjusted. So double check.

Note, when the head is removed DO NOT rotate the crankshaft without some sort of cylinder hold-down in place. It is possible that moving the pistons (i.e. turning the crankshaft) will cause an un-clamped liner to move thus possibly ruining its seal to the block at the bottom of the cylinder. If that happens, you will get coolant in the oil!
 

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send the head to a machine shop to be resurfaced and balanced. about 180$ but since headgasket tends to go due to an overheating incident, they can warp.

dont buy the crap about no gasket-sealant. its a misinterpretation (or likely translation) of a bulletin that says not to use 'Silicon-based' sealants. it suggests Hylomar or Permatex NON-HARDENING sealant that can be removed without scraping.


i highly recommend the new blue over-lipped valve eyelet inserts that IAP sells. they completely remedy the leakage in the back of the valve cover.
 

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.....on the 'o; rings i have had great luck with small block) chevy) valve guide seals..they are not like our valve guide seals. the g.m. version are 'o' rings.. a machine sjop gave me 20-30 of them when i asked for 6 of them..they have lots of them in machine shops:):) ")
 

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Discussion Starter #7
Thanks for the advice. I plan on ordering the parts soon and hope to start the project in the next few weeks. Hopefully it goes smooth. If it does I will give a glowing summary of what a good mechanic I am, if not I will scramble to the computer in a panic and ask for help.
 

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Get the following:

Reinz HG
ultra grey permatex
viton o rings
reuseable valve cover gasket
8 exhaust manifold nuts and lock washers
4 exhaust manifold gaskets
1 intake gasket
seems like you'll need 8 intake valve guides if you want to put stem seals on the exhaust side as well as the intake

then either....

teflon valve stem seals from centerline.

or

viton valve stem seals from IAP.

GET THE GUIDES FROM THE SAME SUPPLIER AS YOU GET THE STEM SEALS! TELL THEM WHAT YOU ARE GOING TO DO IF YOU ARE STEM SEALING ALL 8 VALVES.

You might wait to order this and see if you need valves. Stems or the poppet may be damaged. If you do one, do them all.

Have the machine shop do a 3 or 4 angle cut on the seats and lap in.
Pressure test and surface the head.
Cut the stems as necessary so that you can get to the available shim range if you are replacing the valves.

Best Regards,
John M
 

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Discussion Starter #10
Is re-lapping the seats of the valves or redoing the valve stem seals that is something I should try to do myself, or something to have a shop do?
 

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Shop. Special tool needed to insert valve guide without damaging it. Have them check the guides too for match with the valve stem. Last ones we got we had to do some additional honing. I should add that in regards to the stem length...shortening the stem will be directly related to the condition of the seats. They may not need cut at all.

Best Regards,
John M
 

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How many miles do you have on the motor? Exhaust guides wear a lot quicker than intake guides. You may not need to replace the intake valves & guides.

I installed my first head gasket completely dry and had no problems but I realized that I may have been lucky. The last two have been Reinz with Permatex Ultra grey.

The only time that I had a problem was when I did not clean the threads on the cylinder head studs and nuts. I got false torque readings and the head gasket failed within 20 miles.

Ed Prytherch
79 Spider
2 x 88 Verde's
 

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Discussion Starter #13
I am moving slowly on the project, but everything came apart well. I ended up having the head essentially rebuilt. I need to reinsert the chain tensioner into the head. Any tips? I plan using a small amount of vasaline to keep the flat moving piece in place until I can get the bolt in place. Any thoughts?
 

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i had trouble with that one..put the head on then found out the tens. was not in..rats....i tryed that heave grease triick. no luk.. so i tok the tens. back out cleand it really good. got some 2 part epoxy and glued the wedge in.. put the tens. back in.. pushed it back and fished around with a short lenth of clothshanger..found out where the wedge hole was..insert the bolt..tapped the tens. a wee bit to break the bond of the epoxy.. worked:):)..oh yes i epoxyed the wedge in about half way on the tens.
 

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I used a blob of grease to hold the wedge in position and then used a quick clamp to push the assembly into place. Peek inside the clamp bolt's hole for the wedge to get into position. Note the clamp bolt is supposed to have a small nipple on the end to mate with a hole in the center of the wedge.

Once the bolt engages the wedge, do not loosen that bolt more than 1/2-1 turn when adjusting the tensioner.
 

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I replaced the exhaust cam last month and loosened the tensioner bolt too much while the chain master link was out. It was a real pain.

What I did was wrapped some electrical tape around the plate/wedge and pushed it into the hole, held the tensioner in place with a crowbar, made sure the hole lined up to the plate/wedge with a mirror and flashlight and tightened it up. It only took about 2 hours, lots of cussing and throwing things around. Final step was to cut the tape with an Xacto knife and remove the electrical tape. After doing this, I told an experienced Alfa mechanic how I did it. His reply was that it was hard to do with the head off the car. I will never loosen the tensioner when the chain master link is off...
 

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Discussion Starter #17
I used a bit of superglue on the plate/wedge and was able to get the tensioner into the block. I cannot imagine trying to do that with the head on the engine.

I got the head on last weekend, it was a bit stuck at first after a tap with a rubber mallat it dropped right down. I used viton rings and permanext ultra-gray. I don't think the pins moved (and obstructed the oil wells) when the head came down, but I guess I will find out when I try to start the engine.
 

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Discussion Starter #18
I put the permanext ultra-gray next to the o-rings. Can I leave it or do I need to pull the head back off and start over?
 

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DO NOT put Permanext Ultra Gray right next to the O-rings. Rather than read the posts that Gary Williams directed me regarding where to put the Ultra Gray, I decided to run a small bead all around the head. Than as set forth in the post above I started to have second thoughts about whether the silicon clogged the oil passages.

I am happy that I pulled the head off the car before putting everything back together. The pictures the oil passages were blocked. Cleaned it all up, and reinstalled with a Hylamar sealant. Took me awhile to get around to it and I had to pay for a second head gasket, but I would have done some serious damage.

It is running great now. Thanks for all of the replies to my questions, and all of the other links available.
 
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